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The production of edible mushrooms presents a serious problem for the environment, since about 5 kg of waste are produced for each kilogram of mushroom. These waste waters have nitrogenous matter. Thus, the aim was to investigate the effect of foliar applications of waste water from the mushroom production process on must amino acid composition during two seasons compared to other nitrogen sources. The treatments were applied to the vineyard at veraison and one week later at a total dose of 0.9 kg N/ha. Amino acids were analysed by HPLC. Results showed that treated mushroom water (Tmw) and mushroom water (Mw) improved the amino acid concentration in both seasons differentially. Tmw applied to the grapevines increased total amino acids concentration from 1479.58 to 1735.90 mg/L compared to untreated grapevines over the second study season. The effectiveness of the applications depends on grapevines nitrogen needs. Under moderate nitrogen conditions, Tmw and Mw applications seem to be more effective than urea and phenylalanine treatments. These results are important in relation to the sustainable management of the agri-food sector., Funding: INIA (project RTA2013-00053-C03-01); CONICYT (BCH/Doctorado – 72170532 to GGG).

11 Pags.- 5 Tabls.- 2 Figs. © 2017 INIA. This is an open access article distributed under the terms of the Creative Commons Attribution (CC-by) Spain 3.0 License., The agronomic performance and leaf mineral nutrition of the non-melting clingstone peach cv. ‘Catherina’ was evaluated on seven hexaploid plum rootstocks, as well as one Prunus persica seedling. They were assessed over a period of 15 years in a field trial at the Experimental Station of Aula Dei-CSIC (Zaragoza, Spain), located in the Ebro Valley (NE Spain). Growing conditions generated varying levels of tree mortality, the highest with Constantí 1, Monpol and Montizo, whereas all Adesoto, GF 655/2 and PM 105 AD trees survived well. GF 655/2 and P. Soto 67 AD proved to be the most dwarfing rootstocks, while Constantí 1 and Monpol were the most invigorating and generated greater cumulative yields. However, the highest yield efficiency was recorded on GF 655/2 and Montizo, although they did not differ significantly from Adesoto and P. Soto 67 AD. The highest average values for fruit weight were observed on PM 105 AD and the lowest on GF 655/2, but they did not differ significantly from the rest of the rootstocks. The highest average values for the soluble solids content were observed on the Pollizo rootstocks Adesoto and PM 105 AD, followed by P. Soto 67 AD. All rootstocks induced nitrogen deficiency, with the exception of Constantí 1, GF 655/2 and Montizo, and iron deficiency, except PM 105 AD. The invigorating rootstock Constantí 1 seemed to induce higher SPAD values. According to the ΣDOP index, Montizo presented the most suitable balanced nutritional index, but it did not differ significantly from the rest of the rootstocks except GF 655/2 and P. Soto 67 AD., Spanish Ministry of Science and Innovation (AGL2005-05533, AGL2008-00283 and AGL2011-24576); co-funding FEDER/Regional Government of Aragón-A44 (RFP 2012-00020).

Training systems are key to manage the tree canopy to take advantage of the tree productivity potential. Assessment of yearly cropping, labor requirements, fruit quality, and orchard profitability were studied. The experiment was organized in a randomized complete block design with three replications. Five different training systems on Quince EMC rootstock and ‘Conference’ as the scion cultivar were compared. The results of this study show that the use of preformed highly feathered trees is an improvement for both, early cropping and profitability. Planting cost, trellis, and labor requirements had a large impact on the economic viability of each system. Tatura produced high yields, but the strong initial investment that needs to be done at planting makes this system a risky investment. Axis 2 seems to be the most suitable system for early cropping while maintaining intermediate plantation costs and an appropriate level of production efficiency. info:eu-repo/semantics/publishedVersion

Aim of study: To evaluate the use of compost and natural rocks as partial replacement of mineral fertilizers in ‘Flame’ seedless grape vineyards.Area of study: The present work was conducted during three successive seasons (2016, 2017 and 2018), being the first season a preliminary trial on 4-yr old grapes cultivated in two different soil types (sandy and clay) at two different locations, Egypt (Abo Galeb, Giza governorate; EL-Mahala, Gharbia governorate).Material and methods: Treatments were applied as natural raw materials at 20, 40, 60, 80 and 100% out of recommended mineral NPK rate. The mineral fertilizers used were ammonium sulfate (21.6% N), calcium super phosphate (15.5% P2O5) and potassium sulfate (48% K2O). The natural rocks used were phosphate rock (22.0% P2O5) and Feldspar (10.12% K2O). Yield and fruit characteristics and leaf mineral content were determined.Main results: Using compost in combination with natural rocks enriched with NPK mobilization bacteria and mineral NPK enhanced leaf nutrients content and gave the highest yield and cluster weight. This mix also improved berries physical and chemical characteristics. There was an increase in soluble solids content (SSC), SSC/acid ratio, and anthocyanin content, associated with a reduction in nitrate content of the berry juice. The most pronounced effect was related to using 60% mineral fertilization + 40% organic and natural rocks in both vineyard locations.Research highlights: We can reduce the recommended doses of mineral NPK by about 40%, reducing then the soil pollution.

Growth control in pear orchards is essential, not just to reduce competition between vegetative and reproductive sinks, but also to improve return bloom, yield and fruit quality. The goal to optimize growth control, return bloom and yield must be pursued with the integration or combination of several strategies. Aim of this study was to assess the use of root pruning, paclobutrazol, and prohexadione-Ca (ProCa) either alone or in combination, to control growth and improve productivity on pear trees. The experiment was conducted during three years in a 10 year-old pear orchard with ‘Blanquilla’ as the scion cultivar. All of the different strategies that were assessed improved growth control in pear trees, with different grade depending on the strategy. Control trees had about 50% of the shoots shorter than 60 cm, root pruning 63%, ProCa 70%, paclobutrazol and root pruning plus ProCa 83%, and root pruning plus paclobutrazol 86%. In addition, yield, fruit weight and return bloom were more affected by applications of ProCa than paclobutrazol. Use of paclobutrazol either alone or in combination with root pruning seems to be most suitable for situations of high-vigor cultivars. The fact that use of paclobutrazol may be challenged again in the future, leave combinations of root pruning plus ProCa as the best shot for vigorous cultivars. In other situations of medium-low vigor, ProCa alone would be the best strategy. info:eu-repo/semantics/publishedVersion

This study aimed to develop a remote sensing-based method for forecasting rice yield by considering vegetation greenness conditions during initial and peak greenness stages of the crop; and implemented for “boro” rice in Bangladeshi context. In this research, we used Moderate Resolution Imaging Spectroradiometer (MODIS)-derived two 16-day composite of normalized difference vegetation index (NDVI) images at 250 m spatial resolution acquired during the initial (January 1 to January 16) and peak greenness (March 23/24 to April 6/7 depending on leap year) stages in conjunction with secondary datasets (i.e., boro suitability map, and ground-based information) during 2007-2012 period. The method consisted of two components: (i) developing a model for delineating area under rice cultivation before harvesting; and (ii) forecasting rice yield as a function of NDVI. Our results demonstrated strong agreements between the model (i.e., MODIS-based) and ground-based area estimates during 2010-2012 period, i.e., coefficient of determination (R2); root mean square error (RMSE); and relative error (RE) in between 0.93 to 0.95; 30,519 to 37,451 ha; and ±10% respectively at the 23 district-levels. We also found good agreements between forecasted (i.e., MODIS-based) and ground-based yields during 2010-2012 period (R2 between 0.76 and 0.86; RMSE between 0.21 and 0.29 Mton/ha, and RE between -5.45% and 6.65%) at the 23 district-levels. We believe that our developments of forecasting the boro rice yield would be useful for the decision makers in addressing food security in Bangladesh.

Nanofertilizers have become a pioneer approach in agriculture research nowadays. In this paper we investigate the delivery of chitosan nanoparticles loaded with nitrogen, phosphorus and potassium (NPK) for wheat plants by foliar uptake. Chiotsan-NPK nanoparticles were easily applied to leaf surfaces and entered the stomata via gas uptake, avoiding direct interaction with soil systems. The uptake and translocation of nanoparticles inside wheat plants was investigated by transmission electron microscopy. The results revealed that nano particles were taken up and transported through phloem tissues. Treatment of wheat plants grown on sandy soil with nano chitosan-NPK fertilizer induced significant increases in harvest index, crop index and mobilization index of the determined wheat yield variables, as compared with control yield variables of wheat plants treated with normal non-fertilized and normal fertilized NPK. The life cycle of the nano-fertilized wheat plants was shorter than normal-fertilized wheat plants with the ratio of 23.5% (130 days compared with 170 days for yield production from date of sowing). Thus, accelerating plant growth and productivity by application of nanofertilizers can open new perspectives in agricultural practice. However, the response of plants to nanofertilizers varies with the type of plant species, their growth stages and nature of nanomaterials.

Certain characteristics of some vegetable crops allow multiple harvests during the production cycle; however, to our knowledge, no study has described the behavior of fruit production with progression of the production cycle in vegetable crops with multiple harvests that present data overdispersion. We aimed to characterize the data overdispersion of zero-inflated variables and identify the behavior of these variables during the production cycle of several vegetable crops with multiple harvests. Data from 11 uniformity trials were used without applying treatments; these comprise the database from the Experimental Plants Group at the Federal University of Santa Maria, Brazil. The trials were conducted using four horticultural species grown during different cultivation seasons, cultivation environments, and experimental structures. Although at each harvest, a larger number of basic units with harvest fruit was observed than units without harvest fruit, the basic unit percentage without fruit was high, generating an overdispersion within each individual harvest. The variability within each harvest was high and increased with the evolution of the production cycle of Capsicum annuum, Solanum lycopersicum var. cerasiforme, Phaseolus vulgaris, and Cucurbita pepo species. However, the correlation coefficient between the mean weight and number of harvest fruits tended to remain constant during the crop production cycle. These behaviors show that harvest management should be done individually, at each harvest, such that data overdispersion is reduced.

Vineyards are usually managed by tilling the inter-rows to avoid competition from other plants for soil water and nutrients. However, in humid and sub-humid climates, such as that of NW Spain, cover crops may be an advantage for controlling vine vegetative growth and improving berry composition, while reducing management costs. The current study was conducted over three consecutive growing seasons (2012-2014) to assess the effects of establishing three permanent cover crop treatments on water relations, vine physiology, yield and berry composition of a vineyard of the red cultivar ‘Mencía’ (Vitis vinifera L.) located in Leiro, Ourense. Treatments consisted of four different soil management systems: ST, soil tillage; NV, native vegetation; ER, English ryegrass (Lolium perenne L.); and SC, subterranean clover (Trifolium subterraneum L.). Midday stem water potential was more negative in the native vegetation treatment, causing significant reductions in leaf stomatal conductance on certain dates. Total vine leaf area and pruning weight was reduced in the cover crop treatments in the last year of the experiment. Yield was unaffected by the presence of a cover crop. No significant differences among treatments were observed for berry composition; however, wines were positively affected by the SC treatment (higher tannin content and colour intensity and lower malic acid concentration when compared with ST). Wines from the cover crop treatments were preferred by taste panelists. These results indicate that in humid climates cover crop treatments can be useful for reducing vine vegetative growth without compromising yield and berry quality.

Phenological studies are important for understanding the influence of climate dynamics on vegetative growth, flowering and fruiting on plants and can be used in many scientific subjects, such as Agronomy, Botany and Plant Biology, but also Climatology as a result of the current global interest in climate change monitoring. The purpose of the detailed specific culture descriptions of the principal growth stages in plants is to provide an instrument for standardization of data recording. To date, there was no coding method to describe developmental stages on saffron plant (Crocus sativus L.). Because of the increasing world-wide interest on this crop, a novel growth development code based on the BBCH extended scale is proposed in this paper. Six principal growth stages were set up, starting from sprouting, cataphylls and flowers appearance, plant appearance and development, replacement corms development, plant senescence and corm dormancy. Each principal growth stage is subdivided into secondary growth stages. Descriptive keys with illustrations are included to make effective use of the system.

© 2015 INIA. The prediction of grape composition is becoming more important due to the need of reducing the current levels of alcohol and pH of the wines, a problem that is exacerbated by climate change. This work presents a 3-year study of the spatial variability of grape composition in a rainfed Tempranillo vineyard located in Rioja (Spain). It is based on the acquisition of multispectral imagery at véraison (start of the ripening process); and zoning based on NDVI, to assess its performance for zonal management. The results reveal a high spatial variability within the plot, with a stable pattern over the years, even with very different climate conditions. NDVI was a good predictor of vegetative growth variables. However, the prediction of grape composition was more complex. Unexpectedly, anthocyanins were found to be higher in the highest vigor zone, which is probably related to the effects of climate change. This unexpected relationship is particularly discussed in the article., This work was financed by a CDTI (Spanish Centre for Industrial Technological Development) program IDI 20110576 in Bodegas Eguren Ugarte (Laguardia, Álava, Spain).

Tobacco is an important cash crop in the world. However, the genetic basis is comparatively narrow among the modern Nicotiana tabacum cultivars, limiting its potential for quality improvement. To introduce genes conferring desirable chemical constituents from medicinal plants, a distant hybridization test was conducted between N. tabacum and Ocimum basilicum L. Seedlings of wild type Nicotiana sylvestris and N. tabacum cultivar 78-04 respectively acted as rootstock and scion. During the flowering season, hand pollination between 78-04 as pistillate parent and O. basilicum as pollen parent was carried out under 22-25°C temperature and 70-80% of relative humidity in the greenhouse. Seed sets of 55% were obtained in 78-04, and about 400 seeds per capsule were produced. But both non-grafted and self-grafted 78-04 plants rarely resulted in fruits by hand pollination and those obtained were without seed. Similar results were obtained in different material combination. The interfamilial F1 hybrids acquired showed distinct variation with various morphological characteristics, and their hybrid nature was confirmed by isozyme and random amplified polymorphic DNA (RAPD) analyses. This result indicated that pollination following grafting can facilitate gene exchange and recombination at the interfamilial level and efficiently overcome barriers of sexual incompatibility between N. tabacum and O. basilicum. Our research not only extends the genetic basis of tobacco but also will provide valuable germplasm for improvement of varieties.

Forage ensilability mainly depends on dry matter (DM), water soluble carbohydrates (WSC) and buffer capacity (BC) values at harvest time. According to these parameters, and based on a collection of 208 forages of known ensilability characteristics including short and long term meadows for grazing, italian ryegrass, maize, triticale, soybean, faba bean crops, and samples coming from cereal-legume associations, the objective of this study has been to define a quantitative ensilability index (EI) based on a relationship between DM, WSC and BC contents at harvest date, adapted to the characteristics of fodder from wet temperate areas. For this purpose, a discriminant procedure was used to define this EI based on a linear combination of DM, WSC and BC of forages at harvest time. The quantitative calculated indexes distinguish five successive ranges of ensilability: high ensilability (EI>+28), medium high ensilability (+9

The growth, phenology and fruit yield of 14 Japanese plum cultivars (Prunus salicina Lindl) were studied in two newly established experimental orchards under organic and conventional management. The experiment was conducted during 2005-2011 in the province of Seville (SW Spain), an important region of Japanese plum culture. Trunk cross-section areas (TCSA), flowering, yield and tree defoliation before winter dormancy were analysed over several years. After one year, TCSA were larger in the organically managed orchard (OMO) for most of the cultivars, in the next two years they were equal, and from the fourth year, several cultivars showed significantly larger TCSA in the conventionally managed orchard (CMO). Flowering in the conventional orchard started from 2 to 6 days before and lasted for 3 to 5 days more than in the OMO. Several cultivars produced significantly more fruit in the CMO, being the average fruit yield in the organic orchard about 72% of the conventionally managed orchard. Autumn defoliation was significantly advanced in the organic orchard, especially in cultivars highly susceptible to rust (Tranzschelia pruni spinosae), a disease not adequately controlled in the organic orchard., Se ha realizado un estudio comparado del crecimiento, la fenología y la producción de 14 cultivares de ciruelo japonés, cultivados desde su plantación en agricultura convencional o ecológica. El estudio se ha realizado durante el periodo 2005-2011 en la provincia de Sevilla, en el suroeste de España, región con una superficie importante de este frutal. Tras un primer año de crecimiento se observó que el área de la sección transversal de tronco (TCSA) fue mayor para la mayoría de los cultivares en la parcela ecológica. Tras el segundo y tercer año de crecimiento los valores de TCSA fueron similares con ambos tipos de manejo agronómico y partir del cuarto año varios cultivares tuvieron siempre valores de TCSA significativamente mayores en la parcela convencional. Varios cultivares han tenido una producción de fruta significativamente superior en la parcela convencional, suponiendo el rendimiento promedio de la parcela ecológica aproximadamente un 72% de la producción convencional. Se ha evaluado varios años la floración y la defoliación previa a la parada invernal. En general se ha observado que los árboles de la parcela convencional han manifestado una floración adelantada de 4 a 6 días con respecto a la parcela ecológica. La duración de la floración en la parcela convencional ha durado de 3 a 5 días más. Se ha observado una defoliación otoñal prematura en la parcela ecológica, más acusada en los cultivares susceptibles a la roya (Tranzschelia pruni spinosae), enfermedad que no se controla bien en manejo ecológico.

The use of almond by products as substrate in greenhouses for growing vegetables has a great economic interest. The objective of this work was to assess the use of two almond by-products (almond shell-AS and almond hull-AH), which had been previously conditioned without composting, as substrates for pepper (cv. Caprino F1) production and to study their effects on the yield, fruit size, and fruit mineral content. Physical, physico-chemical, and chemical characteristics of the almond by-products were determined both initially and during the pepper growing season. Initially, all values of the parameters studied ― except sulfur and iron ― differed significantly between the two substrates. During cultivation, the 18 substrate parameters and variables tested - except bulk density - exhibited significant variations with time for AS; the same occurred for AH, exceptions being pH, total nitrogen Nt, N-NH4, bulk density, and manganese. The changes in both substrates for the K, N, and S concentrations were significant. The nutrient levels in AH were higher than for AS. The almond shell and almond hull substrates produced slight decreases in total fruit yield with respect to the control (0.79 and 3.22 for AS and AH, respectively), with a lesser decrease for AS, due to reductions in the number of fruits per plant rather than to reductions in individual fruit weight. The plants grown on the AS and AH substrates showed a decrease in total fruit yield, due to reductions in the number of fruits per plant rather than reductions in individual fruit weight., El objetivo del trabajo es evaluar el efecto de dos subproductos de la almendra (cáscara/endocarpio – AS y corteza/mesocarpio – AH) acondicionados para ser utilizados como substratos para la producción de pimiento dulce en invernadero y estudiar los parámetros de calidad y la composición mineral de los frutos. Los substratos utilizados fueron caracterizados, de la totalidad de parámetros estudiados inicialmente se encontraron diferencias significativas entre ambos subproductos, excepto para azufre y hierro. Durante el desarrollo del cultivo, los 18 parámetros estudiados de ambos substratos mostraron para AS ser significativos con la evolución excepto para la densidad aparente e igual ocurrió para AH con excepción del pH, Nt, N-NH4, la densidad aparente y el Mg. Las variaciones en las concentraciones de K, N y S fueron significativas para ambos substratos. Los niveles de nutrientes en el substrato AH fueron superiores a los de AS. Ambos substratos ensayados dieron lugar una ligera disminución de la producción total de pimiento respecto al control, menor para la cáscara (AS), debido a la reducción del número de frutos por planta respecto a la reducción de peso de los frutos individuales, resultando el substrato AS equivalente al control.

The present study was conducted to determine the mitigating influence of greenhouse CO2 enrichment on the negative effects of salinity in Mediterranean conditions. Hybrid Raf (cv. Delizia) tomato plants were exposed to two salinity levels of the nutrient solution (5 and 7 dS/m) obtained by adding NaCl, and two CO2 concentrations (350 and 800 μmol/mol) in which CO2 enrichment was applied during the daytime according to a strategy linked to ventilation. Increasing water salinity negatively affected the leaf area index (LAI), the specific leaf area (SLA), the water use efficiency (WUE), the radiation use efficiency (RUE) and dry weight (DW) accumulation resulting in lower marketable yield. The high salinity treatment (7 dS/m) increased fruit firmness (N), total soluble solids content (SSC) and titratable acidity (TA), whereas pH was reduced in the three ripening stages: mature green/breaker (G), turning (T), and pink/light red (P). Also, the increase in electrical conductivity of the nutrient solution led to a general change in intensity of the sensory characteristics of tomato fruits. On the other hand, CO2 enrichment did not affect LAI although SLA was reduced. RUE and DW accumulation were increased resulting in higher marketable yield, through positive effects on fruit number and their average weight. WUE was enhanced by CO2 supply mainly through increased growth and yield. Physical-chemical quality parameters such as fruit firmness, TA and pH were not affected by CO2 enrichment whereas SSC was enhanced. Greenhouse CO2 enrichment did mitigate the negative effect of saline conditions on productivity without compromising organoleptic and sensory fruit quality.

The objective of the present study was to investigate the limitations of irrigation with saline reclaimed wastewater (RW) for producing potted weeping fig (Ficus benjamina L.). Furthermore, two different levels of leaching were studied to ascertain whether either reduces the negative effects of RW. Three irrigation treatments were applied: a) well water (control), b) RW (5 dS m-1) with a constant leaching fraction of 23% (RWL), and c) RW (5 dS m-1) with a constant leaching fraction of 15% and 50% flushing every nine irrigation events (RWF). After five months of exposure to the RW, plant size, leaf area, specific leaf area, plant DW, stem diameter and shoot/root ratio were reduced, but both compactness and the appearance of the plants remained high. RWF reduced leaf area, plant dry weight, stem diameter, leaf lightness, leaf chroma and leaf SPAD compared with the RWL. Water consumption per pot was higher in control (50.58 L), followed by RWL (24.29 L) and RWF (19.6 L). Photosynthesis and stomatal conductance were 50% lower in RWL plants than in the control, while the RWF plants had the lowest rates. RWF caused damages in the photochemical apparatus. This study confirms that: a) weeping fig is a good candidate for being grown with saline RW without compromising its aesthetic value; b) RW may be regarded as a good alternative to the retardants used in this plant; and c) the recommended irrigation would be RWL., El objetivo del estudio fue investigar las limitaciones del riego con agua residual regenerada salina (RW) en la producción de Ficus benjamina L. en maceta. Se valoró también la efectividad de dos de niveles drenaje para reducir los efectos negativos del RW. Los tratamientos fueron: a) agua no salina (control), b) RW con 5 dS m-1 y un 23% de drenaje (RWL), y c) RW con 5 dS m-1 y un 15% de drenaje, más un 50% de lavado cada 9 riegos (RWF). Después de 5 meses bajo RW el tamaño de la planta, área foliar, área foliar específica, peso seco de la planta, diámetro del tallo y el ratio parte aérea/raíz fueron reducidos, mientras que la compacidad y el aspecto ornamental estuvieron dentro de los patrones comerciales adecuados. RWF produjo una disminución del área foliar, peso seco de la planta, diámetro del tallo, luminosidad y saturación del color de la hoja, y de la clorofila foliar (SPAD) en comparación con RWL. El consumo de agua fue mayor en el control (50,58 L), seguido de RWL (24,29 L) y RWF (19,6 L). La fotosíntesis y la conductancia estomática fueron un 50% menor en las plantas bajo RWL respecto al control, mientras que las plantas bajo RWF presentaron los registros más bajos. RWF produjo daños en el aparato fotoquímico. Este estudio indica que: a) F. benjamina puede ser cultivado con RW sin comprometer su valor estético, b) el riego con RW resultó una buena alternativa al uso de retardadores químicos, y c) el riego recomendado es RWL.

In the Mediterranean region, some wild edible species such as Asparagus acutifolius L. are still harvested and even marketed. Considering the great interest of this species, including its recreational, commercial and agronomic uses, we aimed to study its natural supply and its current scale of harvesting. Nearly 50 plants were monitored in two sites of Central Spain. An experimental harvest of 100% of spears was conducted during spring 2008-2009 to estimate spear production per plant and per hectare. Plants were also monitored but not harvested in 2010-2011 at Site 1 to document real gathering practices and its influence on yield. Spear production ranged from 5.0 to 12.8 g per plant and from 4.0 to 8.9 kg ha-1, reaching the top-ranked values in May (30-60% of total yield). Between-site variations on yield were mainly related to spear number rather than to spear weight, whereas weather conditions influenced annual yields. The percentage of plants harvested by local foragers varied from 26 to 47%. A slight but not significant trend for collecting the largest spears was recorded. According to spear number in harvested (1.8-2.5 spears) and non-harvested plants (1.3-1.5 spears), gathering seemed to promote the growth of new spears, although further research is needed to assess its influence in the long term. Results suggest that foraging is a time-consuming practice, thus social and cultural factors may explain its high appreciation in present times., En la región mediterránea, especies como el espárrago triguero (Asparagus acutifolius L.) siguen siendo recolectadas y a veces incluso vendidas en mercados locales. Dado el interés de esta especie, tanto recreativo como agronómico o comercial, en este trabajo se estima su producción natural y su presión recolectora en la actualidad. Para ello se realizó el seguimiento de casi 50 esparragueras silvestres en dos localidades del centro de España. En la primavera de 2008 y 2009 se recolectaron el 100% de los espárragos para estimar el número y peso de espárragos por planta y por hectárea. La presión recolectora se ha estudiado durante los años 2010-2011 en las mismas plantas de una de las dos poblaciones. La producción estimada fue de 5,0-12,8 g por planta y 4,0-8,9 kg ha-1, alcanzando los valores más altos en mayo (30-60% del rendimiento total). Entre localidades aparecieron mayores diferencias en el número de espárragos que en el peso de los mismos. Las condiciones meteorológicas influyeron en los rendimientos anuales. Se observó que el 26-47% de las esparragueras fueron cosechadas por recolectores locales. Se detectó una ligera pero no significativa tendencia a recolectar los espárragos de mayor tamaño. Basándonos en el número de espárragos de las plantas recolectadas (1,8-2,5 espárragos) y no recolectadas (1,3-1,5 espárragos), parece que la recolección promueve el crecimiento de nuevos espárragos, aunque se precisa corroborarlo con una investigación a más largo plazo. Los resultados sugieren que la recolección de espárragos es una práctica que consume mucho tiempo, por lo que seguramente existen otros factores sociales y culturales que explican el aprecio que se les tiene en la actualidad.

The hedgerow orchard type is being increasingly used with the olive although not much information is still available about its suitability to this species. The objective of this study was to assess the influence of planting density (312, 416, 625 and 1,250 trees ha-1) on vigour and productive characteristics of ‘Arbequina’ olive trees planted in 2003. Significant linear regressions have been observed between planting density and tree width, trunk cross section area and canopy volume. Increasing planting density showed positive linear correlation (R2=0.63) with canopy volume per hectare. There was a negative correlation between planting density and production per tree in the five first crops, but it was positive with production per hectare both in olive and olive oil production with coefficients of determination ranging from 0.16 to 0.43 and from 0.28 to 0.46, respectively. A significant linear regression (R2= 0.31 and 0.48) was found between planting density and fruit size on two of the studied cropping years. Our results have not allowed establishing any relationship between planting density and fruit oil content. Finally, the studied densities did not affect the oil fatty acid composition. The production increase observed at the highest tried density is linked to the increase in canopy volume per hectare, but these results should be checked at later stages of tree development, as this study covers only until the fifth harvested crop., El cultivo en seto está siendo cada vez más usado en olivo aunque todavía no hay demasiada información acerca de su idoneidad para esta especie. El objetivo de este estudio fue evaluar el efecto de la densidad de plantación (312, 416, 625 y 1.250 árboles ha-1) sobre las características de vigor y productivas de árboles de ‘Arbequina’ plantados en 2003. Se han observado regresiones significativas entre la densidad de plantación y la anchura del árbol, el área de su sección de tronco y su volumen de copa. La densidad de plantación ha mostrado una relación lineal positiva (R2= 0,63) con el volumen de copa por hectárea. Hubo una correlación negativa entre la densidad de plantación y la producción por árbol de los cinco primeros años, pero fue positiva con la producción por hectárea, tanto de aceituna como de aceite, con coeficientes de determinación que variaron entre 0,16 y 0,43 y entre 0,28 y 0,46, respectivamente. Se encontró una regresión significativa (R2= 0,31 y 0,48) entre la densidad de plantación y el tamaño de los frutos en dos de las cosechas estudiadas. Nuestros resultados no han permitido establecer ninguna relación entre la densidad de plantación y el contenido en aceite del fruto. Finalmente, las densidades de plantación empleadas no afectaron a la composición acídica del aceite. El aumento de producción observado a las mayores densidades de plantación está asociado al incremento de volumen de copa por hectárea, pero estos resultados deben ser confirmados con árboles de mayor desarrollo, puesto que este estudio solo llega hasta la quinta cosecha recolectada.

The need to reduce nitrogen (N) fertilizer pollution strengthens the importance of improving the utilization efficiency of applied N to crops. This requires knowledge of crop N uptake characteristics and how fertilization management affects it. A three-year field experiment was conducted from May to September in central Spain to investigate the influence of different N rates, which ranged from 11 to 393 kg ha-1, applied through drip irrigation, on the dynamics of N uptake, nitrogen use efficiency (NUE), fruit yield and quality of a ‘Piel de sapo’ melon crop (Cucumis melo L. cv. Sancho). Both N concentration and N content increased in different plant parts with the N rate. Leaves had the highest N concentration, which declined by 40-50% from 34-41 days after transplanting (DAT), while the highest N uptake rate was observed from 30-35 to 70-80 DAT, coinciding with fruit development. In each year, NUE declined with increasing N rate. With N fertilizer applications close to the optimum N rate of 90-100 kg ha-1, the fruits removed approximately 60 kg N ha-1, and the amount of N in the crop residue was about 80 kg N ha-1; this serves to replenish the organic nutrient pool in the soil and may be used by subsequent crops following mineralization., La necesidad de reducir la contaminación procedente de la aplicación de fertilizantes nitrogenados refuerza la importancia de mejorar la eficiencia de utilización del nitrógeno aplicado a los cultivos. Durante tres años se realizaron ensayos de campo al aire libre en los meses de mayo a septiembre en la zona centro de España para investigar la influencia de distintas dosis de N, en la dinámica de absorción de N, eficiencia del uso del N (NUE), producción y calidad de un cultivo de melón (Cucumis melo L. cv. Sancho) ‘Piel de sapo’. Las dosis de N variaron desde 11 a 393 kg ha-1 y se aplicaron a través del riego por goteo. Tanto la concentración como el contenido de N aumentaron en las distintas partes de la planta a medida que la dosis de N aumentó. La hoja fue el órgano con la mayor concentración de N, decreciendo un 40-50% a partir de los 34-41 días después del transplante (DAT). La tasa de absorción de N más alta se observó desde los 30-35 hasta los 70-80 DAT, coincidiendo con el desarrollo del fruto. En cada año, el NUE descendió con el incremento de la dosis de N. Con aplicaciones de N cercanas a la dosis óptima de 90-100 kg ha-1, los frutos extrajeron aproximadamente 60 kg N ha-1, y la cantidad de N en el residuo del cultivo estuvo alrededor de 80 kg N ha-1. Este residuo sirve para rellenar la reserva de nutrientes orgánicos del suelo y puede ser usado por los cultivos posteriores después de su mineralización.

To study the process of composting of grape marc and test the resulting compost as a substrate for the cultivation of ornamental plants, six composting processes, with mixtures of dealcoholised grapevine marc and grape stalk (DM+GS) in a 1:1 ratio (v:v), were carried out in Seville (Spain) between 2000 and 2006. The duration of the composting ranged between 20 and 24 weeks in the Spring-Summer season. Weekly, temperature, pH, EC, N-NO3- and N-NH4+, were measured. The maximum temperatures reached values of 65-73°C at a depth between 40 and 80 cm. The compost had a slightly alkaline pH, slightly salinity, high organic matter and total nitrogen contents. The final compost chemical composition in total elements showed values in the same range as those corresponding to plant material, except for Fe. The distribution in the size of the particles gives way to a total porous space that is close to the one considered as optimal in a substrate for soilless cropping. Pore size distribution showed a prevalence of big pores that produces unbalance in the water-air ratios, resulting in a material with a good aeration but with low water retention. The composts were tested as substrates for four ornamental species: geranium, petunia, carnation and gerbera. The results suggest that compost has no limiting characteristics for its use as a medium for the cultivation of ornamental plants in container, and can replace conventional substrates, such as peat and coconut fibre., Para estudiar el proceso de compostaje de orujos de uva y probar el compost resultante como sustrato para el cultivo de plantas ornamentales, se llevaron a cabo, en Sevilla (España) entre 2000 y 2006, seis procesos de compostaje, con mezclas de orujos de vid desalcoholizados y tallos de vid o raspón (DM + GS) en una proporción 1:1 (v:v). La duración del compostaje osciló entre 20 y 24 semanas en el período de primavera-verano. Se midieron semanalmente temperatura, pH, CE, N-NO3- y N-NH4+. Se alcanzaron temperaturas máximas de 65 a 73°C a 40-80 cm de profundidad. El compost resultante tenía pH ligeramente alcalino, moderada salinidad, altos contenidos en materia orgánica y nitrógeno total. Los análisis químicos del compost mostraron niveles de elementos totales en igual rango que los correspondientes a material vegetal, excepto Fe. La distribución del tamaño de partículas del material origina un espacio poroso total cercano al considerado óptimo en los sustratos para cultivo sin suelo. La distribución del tamaño de poros mostró una prevalencia de poros grandes, circunstancia que produce un desequilibrio en las relaciones aire-agua, dando como resultado un material con buena aireación, pero con baja retención de agua. Los composts se probaron como sustratos para cuatro especies ornamentales: geranio, petunia, clavel y gerbera. Los resultados no sugieren ninguna característica limitante para el uso del compost como medio para el cultivo de plantas ornamentales en contenedor, y puede sustituir a los sustratos convencionales como la turba y la fibra de coco.

The use of grafted plants in vegetable crop production is now being expanded greatly. However, few data are available on the nutritional composition of grafted vegetables with emphasis on antioxidant properties. Therefore, the major objective of this study was to evaluate antioxidant components of tomatoes influenced by grafting technique. The tomato plants were grown in a greenhouse located at Kriz˘evci, Croatia. The cultivars ‘Efialto’, ‘Heman’, and ‘Maxifort’ were used as rootstocks, while ‘Tamaris’ was used as scion. Grafting resulted in increase of number of marketable fruits per plant by 30%. Content of total vitamin C and total phenolics significantly decreased after grafting. The concentration of total extractable phenolics in tomatoes ranged from 287.1 to 977.4 mg gallic acid equivalents (GAE) kg–1 fresh weight, whereas lycopene content ranged from 11.44 to 60.99 mg kg–1 fresh weight. Antioxidant activities determined by 1,1-diphenyl-2 picrylhydrazyl (DPPH) method of grafts were significantly different compared to their respective rootstocks. The overall results showed that tomato grafting on suitable rootstocks has positive effects on the cultivation performance, but decreases nutritional quality of tomatoes., En la producción de cultivos hortícolas se está expandiendo actualmente de forma considerable el uso de plantas injertadas. Sin embargo, hay pocos datos disponibles sobre la composición nutricional de las hortícolas injertadas, especialmente sobre sus propiedades antioxidantes. El principal objetivo de este estudio fue evaluar los componentes antioxidantes de tomates influenciados por la técnica de injerto. Se cultivaron plantas de tomate en un invernadero de Kriz˘evcii, Croacia. Se utilizaron como portainjertos los cultivares ‘Efialto’, ‘Heman’, y ‘Maxifort’, mientras que ‘Tamaris’ fue utilizado como injerto. El resultado del injerto fue un aumento del 30% en el número de frutos comerciales por planta, mientras que el contenido de vitamina C y de fenoles totales disminuyó significativamente. La concentración del total de fenoles extraíbles en los tomates varió entre 287,1 y 977,4 mg de equivalentes de ácido gálico (GAE) por kilo sobre la base de peso fresco, mientras que el contenido de licopeno varió desde 11,44 hasta 60,99 mg kg–1 de peso fresco. Las actividades antioxidantes determinadas por el método DPPH (2,2-difenil-1-picrilhidrazilo) de los injertos fueron significativamente diferentes respecto de sus respectivos patrones. Los resultados globales muestran que el injerto de tomate sobre patrones adecuados tiene efectos positivos sobre el rendimiento de cultivo, pero la calidad nutricional de los frutos disminuye.

In a previous study, the crop simulator CropSyst was evaluated against crop data collected on rice varieties grown in Northern Italy. The need of model re-parameterization became apparent after investigating new field data, as inconsistencies in the simulation of leaf area index emerged for Indica-type varieties. Key parameters (specific leaf area, stem-leaf partition, extinction coefficient, light-to-biomass conversion efficiency) derived from field measurements (respectively, 27 square m/kg, 3.6 square m/kg, 0.53, 3.2 g/MJ) considerably differed from those previously obtained via calibration (39 square m/kg, 1.5 square m/kg, 0.50, 3.0 g/MJ). Such new parameters are informative for suitable modelling of rice systems. The agreement between simulated and observed above ground biomasses was similar with both parameter sets: average general standard deviation = 25% (previous) and 26% (new); average modelling efficiency = 0.90 (previous) and 0.87 (new). Such comparisons demonstrate as the accumulation of aerial biomass in crop models can be depicted in different ways and reasonable estimations can be achieved by different pathways (not all acceptable). A check on parameters like the one performed here (field measurements versus calibrated parameters) is worth to give protection against spurious conclusions while indicating whether the parameterization is conceptually consistent and related to reality., En un estudio anterior se evaluó el modelo de cultivos CropSyst para simular la biomasa aérea de variedades de arroz cultivadas en Italia del norte. En ese estudio, la bondad de la parametrización presentó simulaciones no confiables para estimar el índice de área foliar con variedades de tipo Indica. Se ha conseguido una nueva parametrización por determinación en campo de parámetros claves del modelo: área foliar específica (SLA=27 m cuadrados/kg), coeficiente de partición tallo/hoja (SLP=3,6 m cuadrados/kg), coeficiente de extinción de la radiación solar (k=0,53) y eficiencia de conversión de la radiación solar en biomasa aérea (LtBC=3,2 g/MJ). Las mediciones efectuadas señalan diferencias con los valores determinados previamente: SLA=39 m cuadrados/kg, SLP=1,5 m cuadrados/kg, k=0,50, LtBC=3,0 g/MJ. La comparación de los resultados experimentales con las simulaciones de biomasa aérea muestra que las diferencias en los resultados provocados por las dos series de parámetros son mínimas: desviación estándar media general igual a 25% (parámetros originales) y 26% (nuevos parámetros); eficiencia media de modelado igual a 0,90 (parámetros originales) y 0,87 (nuevos parámetros). Se comprueba que la acumulación de biomasa puede ser modelada para varias combinaciones de valores alternativos de parámetros que, incluso si permiten conseguir resultados parecidos, no todos corresponden a la realidad biofísica simulada. Se debe realizar un control sobre los parámetros claves de un modelo, similar a lo que ha sido hecho en este estudio, para prevenir conclusiones espurias e incorrectas y para verificar si la parametrización se fundamenta con la realidad del sistema modelado.

The business dynamics of the agricultural sector generally call for a system of calculation and cost management that goes beyond output assessment and profit determination, and coordinates a tool that supports the decision-making process, thus facilitating the evaluation of different cultivation techniques, varieties and so on. Accordingly, this paper proposes using a cost model based on activities for calculating and managing production costs in multiproduct firms in the agricultural sector, using ornamental plant cultivation as a case in point. This particular case may be considered extremely difficult in terms of crop variety and likely destinations for the products (commercialization, self-supply, etc.). Consequently, the proposed model is transparent, flexible, simple to apply and understand, and easily adaptable to the peculiarities of firms in the agricultural sector in general., Las empresas del sector agrícola requieren un sistema de cálculo y gestión de costes que proporcione información más allá de la simple valoración del producto y de la determinación del resultado, sino que se demanda una herramienta conjunta que ayude en la toma de decisiones y facilite la evaluación de la utilización de diferentes técnicas de cultivos o diferentes variedades. Así, este trabajo propone usar un modelo de coste basado en las actividades para calcular y gestionar los costes de producción de las empresas agrícolas multiproductoras, empleando como caso de estudio el cultivo de plantas ornamentales, por considerarlo de mayor complejidad en términos de productos gestionados y destino de los mismos. El modelo propuesto es transparente, flexible, sencillo de aplicar y entender, y fácilmente adaptable a las características propias de otras empresas del sector agrícola en general.

The agronomic performance of different proportions of mixtures of coconut fibre (CF) pith and spent mushroom substrate (SMS) was studied for their use as casing material in mushroom cultivation. After chemical and biological characterisation of the casing substrates qualitative and quantitative production parameters were evaluated in a cycle of Agaricus production. An increase in the proportion of SMS reduced the number of carpophores and overall yield; while the first flush was delayed, mushroom size tended to increase and the mushrooms had a higher dry matter content and a better texture, although their colour was worse. Combinations of CF pith and SMS of 4:1 and 3:2 (v/v) gave biological efficiencies of 92.9 and 82.6 kg/100 kg compost, respectively. These values compare well with that obtained from the commercial casings used as a control. The high electrical conductivity of the mixture containing the highest proportion of SMS would limit its use. However, the results indicate the viability of reusing SMS as an ingredient of casing material for mushroom cultivation. This alternative could be considered to partially replace the organic substrates normally used for mushroom cultivation, with the double advantage of decreasing cost and reducing the environmental impact of waste disposal., Se describe en el presente trabajo el estudio del comportamiento agronómico proporcionado en cultivo de champiñón por sustratos de cobertura basados en mezclas de fibra de coco (CF) y compost agotado (SMS) en diferentes proporciones. Para ello, tras la caracterización física, química y biológica de los sustratos de cobertura, se evaluaron los parámetros de producción cualitativos y cuantitativos en un ciclo de cultivo de Agaricus bisporus. Se observó que al aumentar la proporción de SMS en las mezclas disminuyó el número de carpóforos cosechados y el rendimiento total, a la vez que se vio retrasada la cosecha de la primera florada, aunque tiende a aumentar el tamaño de los champiñones cosechados, que presentan mayor contenido en materia seca, mejor textura y peor coloración. Combinaciones de CF y SMS 4:1 y 3:2 (v/v) proporcionaron, respectivamente, eficiencias biológicas de 92,9 y 82,6 kg/100 kg compost, comparables a las proporcionadas por las coberturas empleadas como testigo. Aunque la elevada conductividad eléctrica de las mezclas con alta proporción de SMS suponen una limitación a su empleo, los resultados obtenidos muestran la viabilidad de la reintroducción del SMS de champiñón en nuevos ciclos de cultivo empleándolo como ingrediente de mezclas de cobertura. Esta aplicación constituye una alternativa a considerar en la producción comercial para reemplazar parcialmente a los sustratos orgánicos empleados habitualmente para este fin, con la doble ventaja de disminuir los costes de elaboración y el impacto ambiental.

This paper reports the effects of different nitrogen (N) fertilizer levels on the growth of maize (Zea mays L.) under field conditions. The N supply was found to influence the growth of the plants, especially the roots. A high N supply significantly inhibited root elongation, and was associated with reduced root dry weight compared to controls and to plants grown with smaller supplies of N. However, no differences were seen in lateral primary root density under the different N supply conditions, nor did plant N concentration increase with high N supply. In conclusion, a high N supply not only wastes resources and pollutes the environment, it may also inhibit root growth., Se llevaron a cabo experimentos de campo para estudiar el efecto de los niveles de fertilizante de nitrógeno (N) sobre el crecimiento de maíz (Zea mays L.). Los resultados demostraron que el suministro de nitrógeno puede influir en el crecimiento de las plantas, especialmente en las raíces. En condiciones de campo, un elevado suministro de N inhibió significativamente la elongación de las raíces. El peso seco de las raíces que crecieron bajo un elevado suministro de N disminuyó comparado con controles o con plantas que crecieron con niveles inferiores de N. Sin embargo, la densidad de las raíces laterales primarias se mantuvo constante cuando las plantas crecieron con diversos niveles de N, y la concentración interna de N de las plantas no aumentó con un elevado suministro de N en el suelo. Un aporte elevado de N no solo desperdicia recursos y contamina el medio ambiente, sino que también puede impedir el crecimiento de las raíces.

This paper combines policy analysis matrix and data envelopment analysis techniques to model the analysis of profitability from farming. Policy analysis matrices are computed for a sample of rice growers located in the wetland of the Albufera (Eastern Spain) under observed conventional and profit-efficient farming conditions. While conventional analysis points to a lack of profitability, farmers are shown to make positive profits at private and social prices when data reflecting efficiency adjustments are used in the analysis. The main conclusion is that the usefulness of the policy analysis matrix might be substantially enhanced by simulating profitability after efficiency-improving managerial decisions have been adopted., Este trabajo combina la matriz de análisis de políticas y las técnicas de análisis envolvente de datos para modelizar el análisis de la rentabilidad de la agricultura. Se calculan matrices de análisis de políticas para una muestra de cultivadores de arroz ubicados en el marjal de la Albufera (Este de España) con datos observados y datos eficientes resultantes de un proceso de maximización de beneficios. Mientras el análisis convencional apunta a una falta de rentabilidad, cuando se introducen en el análisis datos que reflejan un comportamiento eficiente los agricultores obtienen beneficios, tanto a precios privados como sociales. La principal conclusión es que la utilidad de la matriz de análisis de políticas puede reforzarse sustancialmente simulando la rentabilidad que se obtendría después de la adopción de decisiones de gestión orientadas a mejorar la eficiencia.

Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria that, as their name suggests, promote plant growth. However, they can also be of help in the biological control of plant diseases. This study reports the effects of two different commercially available strains of Bacillus amyloliquefaciens (FZB24 and FZB42) on tomato production in open and closed systems in the presence of different amounts of nutrients. Three factors were tested: (1) the type of nutrition system (open or closed), (2) the concentration of the nutrient solution (full or half strength), and (3) the PGPR applied (either B. amyloliquefaciens FZB24 or B. amyloliquefaciens FZB42, or a no-PGPR control). Perlite was used as the growth medium. Variables related to water use efficiency, yield and fruit quality were assessed. The use of half strength nutrient solution was sufficient for full growth in the open system in both spring and autumn seasons. However, the same strength nutrient solution was associated with reduced yields in the closed system during the autumn season. The application of either strain of B. amyloliquefaciens increased the yield of the tomato plants by 8-9% in the open system in the spring, whereas they had an adverse effect on yield in the closed system under half strength nutrient solution conditions during the autumn., Las rhizobacterias promotoras del crecimiento de las plantas (PGPR) son bacterias que viven libres y, como su nombre indica, promueven el crecimiento de las plantas. Sin embargo, también pueden ser de ayuda en el control biológico de las enfermedades de las plantas. En este estudio se investigaron los efectos de dos cepas comerciales de Bacillus amyloliquefaciens (FZB24 y FZB42) sobre la producción de tomate en sistemas abiertos y cerrados, en presencia de diferentes cantidades de nutrientes. Los tratamientos fueron: (1) tipo de sistema de nutrición (abierto o cerrado), (2) concentración de nutrientes (solución nutritiva completa o incompleta), (3) la PGPR aplicada (B. amyloliquefaciens FZB24, B. amyloliquefaciens FZB42, o un control sin PGPR). Se utilizó perlita como medio de crecimiento. Se evaluaron las variables relacionadas con la eficiencia del uso del agua, producción de tomate y calidad del fruto. La solución de nutrientes menos concentrada fue suficiente para un pleno crecimiento en el sistema abierto en ambas estaciones (primavera y otoño). Sin embargo, la misma solución de nutrientes disminuyó en otoño la producción en el sistema cerrado. La aplicación de ambas cepas de B. amyloliquefaciens aumentó la producción de las plantas de tomate un 8-9% en el sistema abierto en primavera, mientras que tuvo un efecto adverso sobre la producción en otoño en el sistema cerrado con la solución menos concentrada.

A field experiment was carried out in 2004 and 2005 to identify the diversity of sunflower (Helianthus annuus L.) pollinators and their influence on seed yield in Makueni district, a semi-arid area in Eastern Kenya. Insect flower visitors were recorded, pollen counted from their body and pollination efficiency index for each visitor determined. Seed yield from plots where insect visitors had access to and where they were denied access was compared. The proportional difference of yield from this pollination scenario was used to estimate monetary net-gain by farmers that could be attributed to insect pollination. In total, individuals belonging to 14 insect species were observed visiting sunflower floral heads. These included six Lepidopteran species, five Hymenopteran species, two Dipteran species, and one Coleopteran species. Apis mellifera L. was the most frequent visitor and had the highest pollination efficiency index. Plots where insect visitors had access produced on average 53% more seed yield compared with plots where insect visitors were excluded. This translates to a net monetary benefit of 51% of the total annual market value of sunflower, accruing to farmers in Makueni district in 2005 due to insect pollination., Se condujo un experimento de campo entre 2004 y 2005 para determinar la diversidad de polinizadores de girasol (Helianthus annuus L.) y su influencia en el rendimiento de semillas en el distrito Makueni, una región semi-árida del Este de Kenia. Se identificaron los insectos vectores de polinización y se contó el polen adherido a sus cuerpos, a fin de determinar el índice de eficiencia de polinización de cada especie. Se comparó el rendimiento de semillas entre las parcelas visitadas y no visitadas por los vectores de polinización. Se estimó la ganancia monetaria neta de los campesinos atribuida a la polinización por insectos. En total, se observaron 14 especies de insectos visitando girasoles, que incluyeron 6 especies de Lepidópteros, 5 de Himenópteros, 2 de Dípteros y un Coleóptero. Apis mellifera L. fue la especie visitante más frecuente y obtuvo el mayor índice de eficiencia de polinización. Las parcelas a las que los insectos tuvieron acceso produjeron como promedio un 53% más semillas que las parcelas de las que los insectos fueron excluidos. Esto implica un beneficio monetario neto del 51% del valor total del mercado anual de girasol, debido a polinización por insectos, para los campesinos del distrito Makueni en 2005.

The use of rootstocks is widespread in modern viticulture; non-grafted Vitis vinifera vines are now grown in only a handful of places with very specific conditions. Since the need to graft vine-scions onto American rootstocks, a lot of work has been performed in which different aspects of the relationship between the vine and the rootstock have been studied. Despite this there are still many open questions, which remained unanswered. The present paper reports a study performed on five "Albariño" clones (MBG-1, MBG-2, MBG-7, MBG-9 and MBG-10), in which the influence of rootstock type (110- R and SO4) on a number of agronomic variables was examined. The results show that these rootstocks have no influence on many of the variables which were studied (phenology, cluster size and weight, fertility, yield, and berry size and weight), although they do influence variables such as the probable alcohol content, the quantity of free-run juice, must total acidity and weight of pruned wood. Therefore it is possible to conclude, that rootstocks influence agronomic parameters., En la viticultura actual está generalizado el uso del portainjerto, y únicamente se cultiva Vitis vinifera sin injertar en zonas muy puntuales del mundo, con unas condiciones muy particulares. Desde que se planteó la necesidad de injertar las viníferas sobre patrones americanos, numerosos trabajos han estudiado diferentes aspectos de la relación vinífera-portainjerto, a pesar de lo cual todavía quedan muchas cuestiones por clarificar. Se estudiaron cinco clones de "Albariño" (MBG-1, MBG-2, MBG-7, MBG-9, MBG-10), en los que se analizaron la influencia de dos tipos de portainjertos (110-R y SO4) en diferentes parámetros agronómicos. Los datos obtenidos han permitido comprobar que el portainjerto no influyó en muchos de los parámetros objeto de estudio (estados fenológicos, peso y tamaño de racimo, fertilidad, rendimiento expresado en kg de uva por cepa, peso y tamaño de baya), pero sí en otros (grado alcohólico probable, rendimiento en mosto yema, acidez total, y peso de madera de poda). Se puede concluir por lo tanto, que el portainjerto influye en los parámetros agronómicos.

Thermal shock and pre-sprouting increase the initial development of potato (Solanum tuberosum L.) plants, allowing for earlier harvests. Growing early potatoes without pre-sprouting is not economically viable under Nordic climatic conditions. The aim of this research was to determine how seed tuber pre-planting treatments (untreated, thermal shock and pre-sprouting) influence time to emergence, mean tuber weight, the number of tubers per plant, and yield (including yield dynamics). The main findings of this work were that thermal shock shortened the time to emergence by 2-5 days, while pre-sprouting shortened it by 7-12 days. In addition, thermal shock significantly increased the number of tubers produced, although their mean weight was lower than that of the tubers produced by the pre-sprouted plants. The presprouted tubers provided a very early harvest of large tubers; the harvest time for the thermal shock-treated tubers was a little later. The untreated seed tubers were the last to produce harvestable plants., El choque térmico y la pre-brotación temprana incrementa el desarrollo inicial de plantas de patata (Solanum tuberosum L.), lo que permite una recolección más temprana. El cultivo de patatas tempranas sin pre-brotación no es económicamente viable en las condiciones climáticas de los países nórdicos. El objetivo de este estudio fue determinar qué tratamiento de presiembra de tubérculos para semilla (sin tratar, choque térmico y pre-brotación) influyen en el tiempo de emergencia, el peso medio del tubérculo, el número de tubérculos por planta, y el rendimiento, incluyendo la dinámica del mismo. Se encontró que el choque térmico de los tubérculos acortó el tiempo de emergencia en 2-5 días y la pre-brotación entre 7-12 días. Además, el choque térmico incrementó el número de tubérculos, aunque su peso fue menor que los tubérculos producidos mediante pre-brotación. Un rendimiento muy temprano es posible con tamaño grande de tubérculo aplicando pre-brotación, siendo el periodo de recolección de tubérculos tratados con choque térmico algo posterior. Los tubérculos sin tratar fueron los que mostraron una menor producción.

Jerusalem artichoke is commonly grown for its edible tubers, livestock feed and as an ornamental. The possibility of growing Jerusalem artichoke for energetic purposes has aroused scientific interest in this species. Despite several studies that have already been done in the last few decades, many aspects of the cropping practice are still relatively unknown. During the growing seasons of 2004-2006 field trials were carried out in NE Portugal. In the experimental period different cropping conditions were imposed, regarding planting density, N fertilization and propagation method. The crop was irrigated in 2004 and 2005 and grown in rain-fed conditions in 2006. The planting densities were 7 plants/square m in 2004, 2, 3 and 4 plants/square m in 2005 and 2 and 4 plants/square m in 2006. Botanical-seed was used in 2005 and seedtubers in all the three years. In 2005, 0 and 100 kg N/ha was combined in a factorial design with the planting densities. The maximum tuber dry matter yield was 18.4 Mg/ha (65.6 Mg/ha, fresh weight basis) and it was recorded in 2005 in the plots where 100 kg N/ha, 2 plants/square m and seed-tubers were combined. The best planting density was 2 plants/square m in irrigated (2005) and rain-fed (2006) conditions. Nitrogen significantly increased tuber yield in 2005 only when seed-tubers were used. Averaged across N fertilization rates and planting densities mean tuber dry matter yields were 12.8 and 6.9 Mg/ha for seed-tuber and botanical-seed, respectively. Leaf mineral composition was little affected by cropping practices. The "Bragança" clone showed high tuber yield potential, although the mean weight of the individual tubers was low which could make mechanization of the harvest difficult. The poor results achieved with botanicalseed argue against its use as an alternative to the seed-tubers., La pataca se cultiva por sus tubérculos comestibles, también se utiliza como forraje y como planta ornamental. La perspectiva de que se pueda cultivar con fines energéticos ha incrementado el interés por esta especie. En los años 2004-2006 se han efectuado experimentos de campo en el NE Portugal, mediante ensayos de diferentes condiciones de cultivo, en cuanto a densidad de plantación, fertilización nitrogenada y métodos de propagación. La plantación se regó en 2004 y en 2005 y se cultivó en secano en 2006. Las densidades de plantación fueron de 7 plantas/m cuadrado en 2004, 2, 3 y 4 plantas/m cuadrado en 2005 y 2 y 4 plantas/m cuadrado en 2006. Se utilizaron propágulos vegetativos en los tres años de ensayo y semilla botánica en 2005. Respecto al N se utilizaron dos tratamientos (0 y 100 kg N/ha) combinados de forma factorial con las densidades de plantación. La máxima producción de materia seca en tubérculos fue de 18,4 Mg/ha (65,6 Mg/ha, en peso fresco) y se obtuvo en las parcelas en las que se combinaron 100 kg N/ha, 2 plantas/m cuadrado y propágulos vegetativos. La mejor densidad de plantación fue de 2 plantas/m cuadrado, tanto en regadío como en secano. La aplicación de nitrógeno aumentó significativamente la producción, pero sólo cuando se utilizaron propágulos vegetativos. Con propágulos vegetativos y semilla botánica se obtuvieron producciones medias de materia seca de 12,8 y 6,9 Mg/ha, respectivamente. La composición mineral de las hojas se vio poco afectada por la técnica de cultivo. El clon "Bragança" ha mostrado elevado potencial de producción, aunque el peso medio de los tubérculos individuales haya sido bajo, lo que puede dificultar la mecanización de la cosecha. Los bajos resultados obtenidos a partir de semilla botánica disuaden su uso en alternativa a los propágulos vegetativos.

Rice tillering is a crucial stage for yield formation. Deep understanding of the relationship between tillering dynamics and yield formation in a particular agrosystem is crucial to boost rice productivity. Research on rice tillering is mainly focused on tropical agrosystems whereas less is done in the Mediterranean, with direct water-seeding and Japonica cultivars. This study aims at characterizing tillering dynamics and identifying the main explanatory tillering traits of yield in a Mediterranean rice agrosystem, Ebro Delta (Northern Spain). A temperate Japonica cultivar grown in Spain, Gleva, was utilized. Plants and tillers were tagged to assess emergence and fertility ratios and grain yield; while changes in tillering number over time, yield and yield components for unit area were measured. Plant and tillering dynamics in the Ebro Delta rice fields can be accurately predicted through equations herein provided, which are based either on thermal time or leaf development. Plants grown under regional standard agricultural practices produced up to eight primary tillers of which two or three become productive. Maximum tiller number was the main explanatory variable of yield while high-yielding tillers within a plant are located on nodes with the highest emergence ratios and, after the main stem, they are the major contributors to yield. The decisive role of tiller development on yield along with the predictability of tiller dynamics raises options to optimize grain yield through tillering modulation. In this sense, results from this study suggests the promotion of early tillering followed by inhibition of late tillering as a strategy of tillering regulation.

The possibilities for increasing the productivity and control of the pea weevil (Bruchus pisorum L.) in field pea (Pisum sativum L.) organic cultivation by the use of following bioproducts NeemAzal T/S and Pyrethrum FS-EC (insecticides), applied individually and in combination with Polyversum (growth regulator and fungicide) and Biofa (foliar fertilizer), as well as to evaluate the stability of the used mixtures were studied. Synthetic products Nurelle D and Flordimex 420 (alone and in combination) were used as a standard. The products were applied once (at budding stage) or twice (at budding and flowering stages). The results showed that forage pea productivity was influenced positively by the application of all organic products. The plants treated with the organic combinations formed an average yield of 3190.2 kg/ha, which was only 4.7% lower than that for the synthetic combination of Flordimex+Nurelle D. The highest yield was produced under application of two mixtures: Biofa+Pyrethrum and Polyversum+Pyrethrum at budding and flowering stages (22.0 and 21.8% above untreated control, respectively). These combinations were also distinguished for their most pronounced protective effect against the attack of the pea weevil and decrease in its numbers of 37.0 and 38.5%, respectively. Pyrethrum was distinguished for a lower degree of damaged seeds and a toxic effect against the pea weevil in comparison with NeemAzal. Technologically the most valuable variant, which united high stability, productivity and protection against pea weevil, was the combination of Biofa+Pyrethrum applied twice. Further investigations are indispensible to expand the range of products (bioinsectides, biofertilizers and growth regulators), which provides good insect control and high productivity in pea organic farming conditions.

12 Pags.- 5 Tabls.- 5 Figs., Calibration of decision tools to improve N fertilizer management is critical to increase its adoption by maize (Zea mays L.) growers. The objective of this study was to establish nitrate and total nitrogen concentrations in the basal maize stalks (BMS) at harvest to separate maize fields among three N availability categories (N-deficient, N-optimum, and N-excess) under Mediterranean irrigated semiarid conditions. We analysed data from 26 irrigated maize trials conducted between 2001 and 2012. Trials included treatments receiving different N fertilizer rates and sources (mineral and organic), irrigation systems (flood, sprinkler) and soil types. The critical nitrate concentration in BMS to identify N-deficient plots (CNCL) is affected by the irrigation system. The CNCL was lower under sprinkler irrigation (708 mg NO3 –– N/kg) than under flood irrigation (2205 mg NO3 –– N/kg), and the later presented a higher degree of uncertainty compared to sprinkler irrigated systems. The results showed the difficulty to identify the N-deficient plots with the BMS test and the higher sensibility of nitrate-N than total-N concentration in BMS to separate N-deficient from N-optimal plots. Under sprinkler irrigation, nitrate in BMS>1500 mg NO3 ––N/kg had a 85% probability of having received an excess of N. Considering economic net returns to N fertilization, the range of nitrate concentration in BMS that maximized profit under sprinkler-irrigated conditions was established between 1100 and 1700 mg NO3 ––N/kg. Results suggest that BMS test can be useful in detecting plots with an excess of N but considering irrigation efficiency is crucial for stablishing successful CNC thresholds.

An experiment was conducted to determine the effects of source of protein (soybean vs sunflower meal) and enzyme supplementation (no enzyme vs protease addition vs protease + xylanase addition) on digestion and growth traits of rabbits. Treatments were arranged factorially in six isonutritive diets. Two hundred and forty rabbits weaned at 25 or 35 days were used to measure dry matter and crude protein apparent ileal digestibility of diets at 35 or 45 days of age, respectively. Another one hundred and eighty animals weaned at 35 days were fed ad libitum in individual cages during four weeks to determine fattening performance. Source of protein did not affect digestion efficiency or feed conversion rate in the whole fattening period, but animals fed soybean meal-based diets showed higher feed intake, grew faster and had higher mortality than those fed sunflower meal-based diets. Addition of enzymes increased ileal apparent digestibility, especially in youngest animals when supplements contained xylanase besides protease activity. Enzyme supplementation did not affect any of the growth traits studied, but decreased fattening mortality in sunflower meal-based diets., Se realizó un experimento para determinar los efectos de la fuente de proteína (harina de soja vs harina de girasol) y de la suplementación enzimática (no suplementación vs adición de proteasas vs adición de proteasas + xilanasas) sobre parámetros digestivos y de crecimiento en conejos en cebo. Los tratamientos se estructuraron factorialmente en seis piensos isonutritivos. Se usaron doscientos cuarenta conejos destetados a los 25 ó 35 días de edad para medir la digestibilidad ileal aparente de la materia seca y de la proteína bruta de los piensos a los 35 ó 45 días de edad, respectivamente. Un grupo adicional de 180 animales destetados a los 35 días de edad fue alimentado ad libitum en jaulas individuales durante 4 semanas para determinar rendimientos productivos en el periodo de cebo. La fuente de proteína no afectó a la eficacia digestiva o a la conversión del alimento en el conjunto del periodo de cebo, pero los animales alimentados con piensos basados en soja crecieron más rápido y presentaron una mayor mortalidad que los que recibían dietas basadas en harina de girasol. La adición de enzimas incrementó la digestibilidad ileal aparente, cuando los suplementos contenían actividad xilanásica además de proteásica, especialmente en los animales más jóvenes. La suplementación con enzimas no afectó a ninguno de los parámetros de crecimiento estudiados, pero redujo la mortalidad en cebo en piensos basados en harina de girasol.

Sprays containing soluble Ca, polypeptidic N and Ti ascorbate in several combinations were applied to cv. Crimson table grape vines (Vitis vinifera L.). Foliar spraying resulted in the accumulation of N, P, K, Ca, Mg, Fe, Zn, Cu and Ti in the leaves, but not of Na, Cl or Mn. In the berries, Ca, Fe, Zn and Cu concentrations increased in the skin and flesh. These berries were also larger than controls, firmer, had a deeper external red colour, and their weight loss during postharvest storage was reduced. The increase in the Ca and micronutrient content of the fruit is explained as a consequence of the beneficial effect of Ti on absorption, translocation and assimilation processes. In turn, improved Ca assimilation by the fruit was responsible for the beneficial effects seen on firmness and storage life., Plantas de uva de mesa de la variedad Crimson (Vitis vinifera L.) se rociaron durante el ciclo de cultivo con disoluciones que contenían Ca soluble, N polipeptídico y ascorbato de Ti, en todas las combinaciones posibles. Las aplicaciones foliares indujeron un aumento de la concentración foliar de todos los elementos, salvo para Cl, Na y Mn. Sin embargo, la composición mineral de la piel y pulpa de los granos de uva sólo se vio afectada en lo que respecta a Ca, Fe, Zn y Cu, que aumentaron significativamente sus niveles. Asimismo, aumentó el tamaño del grano, su consistencia y color rojo, al tiempo que disminuyó la pérdida de peso durante el almacenamiento. La inducción de la concentración de Ca y de los tres oligoelementos en los tejidos del grano de uva se explica por el conocido efecto inductor de los bioactivadores, en especial del Ti, sobre los procesos de absorción, transporte y asimilación en el fruto. A su vez, el aumento de la cantidad de Ca metabolizado en piel y pulpa es responsable de los beneficios obtenidos en consistencia y vida útil del fruto.

Rosemary plants were analysed using HPLC and eight different compounds (vanillic acid, caffeic acid, rosmarinic acid, naringin, hispidulin, cirsimaritin, carnosol and carnosic acid) were identified and quantified. The analysis of the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity revealed that rosmarinic and carnosic acids were the best rosemary scavengers with IC sun(50) values of 27 and 32 micro M, respectively. Environmental influences on rosmarinic and carnosic acids content in rosemary plants were studied over a period of one year under southern UK conditions. Carnosic acid reached the maximum concentrations in December, decreasing by 50% during the summer months, while rosmarinic acid showed a constant concentration during the year. The significance of these results has been discussed later in this paper., Se analizaron plantas de romero usando HPLC, hallando ocho compuestos diferentes los cuales fueron identificados y cuantificados. El análisis de la capacidad antioxidante, analizada usando el radical DPPH, reveló que los ácidos rosmarínico y carnósico presentaron una alta capacidad antirradicalaria con valores de IC sub(50) de 27 y 32 micro M respectivamente. La influencia de las condiciones ambientales del sur de Inglaterra en el contenido de los ácidos rosmarínico y carnósico en plantas de romero fue estudiada durante un periodo de un año. Los resultados mostraron que el ácido carnósico alcanzó concentraciones máximas durante el mes de diciembre, disminuyendo su concentración en un 50% durante los meses de verano. El ácido rosmarínico mostró, sin embargo, una concentración casi constante durante todo el año. La importancia de estos resultados ha sido argumentada a lo largo de este artículo.

The effects of pre-sowing magnetic treatments on the growth and yield of tomatoes (cv. Vyta), cultivated late in the season, were studied under field conditions. Tomato seeds were exposed either to a 120 mT dynamic magnetic field (induced by an experimental electromagnet) for 10 min or to a 80 mT field for 5 min. Non-treated seeds were used as controls. Plants were grown in experimental plots (20.2 square m) and cultivated according to standard agriculture practices. At physiological maturity, the plants were harvested from each plot and the number of fruits, mean fruit weight, fruit yield per plant and fruit yield per area determined. In the nursery stage, the treatments led to a significant increase in root length, fresh and dry root weight, stem length, fresh and dry stem weight, leaf area and foliole dry weight. During the vegetative stage, the leaf, stem and root relative growth rates of plants derived from magnetically-treated seeds were greater than those shown by control plants. In the generative stage, the relative growth rate of the fruits belonging to the "magnetically treated plants" was greater than that of control plant fruits. At the fruit maturity stage, the magnetically treated seeds produced plants with significantly more fruits (17.9-21.3%), with a significantly greater mean fruit weight (22.3-25.5%), and with a greater fruit yield per plant (47.3-51.7%) and per area (48.6-50.8%) than did the control plants. Pre-sowing magnetic treatments would appear to enhance the growth and yield of tomatoes cultivated late in the season., Se estudiaron los efectos de tratamientos magnéticos presiembra sobre el crecimiento y rendimiento del tomate (cv Vyta), cultivado en período tardío en condiciones de campo. Las semillas de tomate se expusieron a campos magnéticos de 120 mT durante 10 min y 80 mT durante 5 min en un electroimán experimental, utilizando simultáneamente semillas sin tratamiento como control. Las plantas se sembraron en parcelas experimentales (20,2 m cuadrados) y se cultivaron de acuerdo con las prácticas agrícolas normales. En la madurez fisiológica, se determinó el número de frutos por planta, la masa promedio de los frutos y el rendimiento por planta y área. En la etapa de semillero, los tratamientos indujeron un incremento significativo de la longitud, masa fresca y seca de la raíz, longitud; masa fresca y seca del tallo; área foliar y masa seca foliar por foliolo. Durante la etapa vegetativa, las tasas relativas de crecimiento de las hojas, tallos y raíces fueron significativamente superiores en los tratamientos magnéticos que en el control, mientras que en la etapa generativa, solamente resultaron significativas las tasas de crecimiento relativo de los frutos. En la etapa de madurez de los frutos, los resultados revelaron que ambos tratamientos magnéticos incrementaron significativamente el número de frutos por planta (17,9-21,3%), masa promedio de los frutos (22,3-25,5%), rendimiento por planta (47,3-51,7%) y rendimiento por área (48,6-50,8%) comparados con el control. Nuestros datos indican que los tratamientos magnéticos mejoraron el crecimiento y rendimiento del tomate cultivado en período tardío.

The aim of this work was to determine whether the local agroecological conditions of the northeast of the Province of Buenos Aires (33 deg 41 min S, 59 deg 41 min W) permit the organic production of leek (cv. Monstruoso de Carentan) seeds. In the 2000/01, 2001/02 and 2002/03 growth seasons, percentage flowering and seed yield (g m-2) and quality were recorded, the latter by determining the thousand grain weight and germination capacity. In the 2001/02 and 2002/3 seasons, the phenological stages of the crop were also determined, as well as the number of hours of cold temperatures experienced and the number of degree days. Significant differences between years were found in the number of days from 50% fruit setting to harvest, probably because three harvests were collected during the first season whereas only one was collected during the second and third. A total of 1,116 and 1,019 hours of cold temperatures and 925 and 1,127 degree days were recorded for 2001/2 and 2002/3 respectively. There were no significant differences between years for yield, percentage flowering or thousand seed weight (average values 78.53 gm-2, 93.36% and 3.55 g respectively). Differences in germination capacity were recorded, but Argentine legislative requirements were always surpassed. Seed yield and quality were comparable to figures cited in the literature. In conclusion, the agroecological conditions of the northeast of the Province of Buenos Aires allow the normal, organic cultivation of this leek cultivar for seed., El objetivo de este estudio fue determinar si las condiciones agroecológicas locales (33 grados 41 minutos L.S.; 59 grados 41 minutos L.O.) permiten satisfacer los requerimientos fisiológicos de la producción de semillas de puerro, cultivado según las normas de la agricultura orgánica. Durante las campañas 2000/01, 2001/02 y 2002/03 se determinaron los porcentajes de floración; los rendimientos de semillas en gm-2 y la calidad, a través del peso de mil semillas y la germinación. En las campañas 2001/02 y 2002/03 se determinaron las etapas fenológicas, las horas de frío y los días grado. No se registraron diferencias estadísticas significativas (alfa = 0,05) entre años en la mayoría de las etapas fenológicas evaluadas. Existieron diferencias entre el 50% de cuaje y la cosecha, probablemente porque durante el primer año se realizaron tres cosechas, mientras que durante el segundo año se efectuó una sola. Se registraron 1.016 y 1.019 horas de frío y 925 y 1.127 días grado, durante las campañas 2001/02 y 2002/03, respectivamente. Los rendimientos (78,53 g m-2), porcentajes de floración (93,36%) y peso de semillas (3,55 g), no arrojaron diferencias estadísticas en tres años de medición. El poder germinativo tuvo diferencias entre años, aunque siempre superando los requerimientos de la legislación argentina. El rendimiento y la calidad de la semilla obtenidos son comparables a los citados en la bibliografía disponible. Las condiciones agroecológicas del noreste de Buenos Aires permiten el desarrollo normal del cultivo de puerro (cv. Monstruoso de Carentan) para la producción de semillas, cultivado según las normas de la agricultura orgánica.

The aim of this work was to determine the effect of storage time and boiling on the colour of sweet potato (cvs. Morada INTA and Regal) root tubers. Increasing storage time more strongly reduced the skin chroma (C*) of raw Morada INTA tubers than that of raw Regal root tubers. The skin hue angle (H) of raw Morada INTA tubers increased linearly with storage time; at the end of the experiment values were almost twice those at baseline. The results of this study suggest that the perception of skin-H is influenced by C*. In both cultivars, storage time more strongly affected the colour variables of the boiled than the raw flesh. Boiling led to a reduction in flesh luminosity (L*) and an increase in flesh-H. The interaction between cultivar and storage time appears to regulate the C* and H values of orange-flesh cultivars., Los objetivos de este trabajo fueron determinar el efecto de la duración del almacenamiento y el estado de cocción (cruda o hervida) sobre el color de las raíces tuberosas de dos cultivares de batata (Morada INTA y Regal). El tiempo de almacenamiento tuvo un mayor efecto sobre el color de la piel de Morada INTA que sobre Regal. Independientemente del cultivar, el efecto del almacenamiento fue reducir la saturación (C*) del color de la piel. El ángulo de color (H) o tono aumentó linealmente con la duración del almacenamiento sólo para Morada INTA, siendo casi el doble al término del experimento que al comienzo. Los resultados de este estudio sugieren que la percepción del tono (H) de la piel está afectada por la intensidad del color (C*). La mayoría de los efectos de los tratamientos sobre el color de la pulpa fueron detectados en raíces hervidas. El hervido causa una disminución en la luminosidad (L*) y un incremento en H, independientemente del cultivar. La interacción entre el cultivar y la duración del almacenamiento regula los valores de C* y H de la pulpa en los cultivares de color anaranjado.

Determining the optimal sowing date is important when evaluating the production potential of any new crop. Field trials were performed with Amaranthus cruentus L., A. hypochondriacus L. and A. mantegazzianus Pass. from 1999 to 2002 in the semi-arid Argentine Pampa in order to establish the best sowing dates for grain production. Crops were sown at 15 day intervals during November, December and January. The following variables were then measured: plant height, days to anthesis, production of biomass, grain production, harvest index, final number of plants and plant losses. Rainfall strongly influenced these variables, depending on sowing date. In all years, A. mantegazzianus produced the lowest grain yields. The latest sowing date is not recommended since the light and temperature conditions during the final part of the phenological cycle have a negative effect on grain yield. The best results were obtained when sowing was performed from the second half of November through to the end of December., La fecha óptima de siembra es un dato esencial cuando se trata de evaluar el potencial de producción de un nuevo cultivo. A fin de establecer el rango óptimo de siembra para la producción de grano en la zona semiárida pampeana de Argentina, se realizaron entre los años 1999 y 2002 ensayos de campo con Amaranthus cruentus L., A. hypochondriacus L. y A. mantegazzianus Pass., probando fechas de siembra cada 15 días aproximadamente durante los meses de noviembre, diciembre y enero. Se midieron las siguientes variables: altura de planta, días a la antésis, producción de biomasa, producción de grano, índice de cosecha, población final de plantas y porcentaje de plantas perdidas. Las precipitaciones en cada año tuvieron incidencia para las variables analizadas, según la fecha de siembra. A. mantegazzianus tuvo menor rendimiento de grano que las otras dos especies en todos los años. La última fecha de siembra no resultó conveniente por la incidencia de las condiciones de luz y temperatura sobre el final del ciclo fenológico de las plantas, originando mermas en el rendimiento. Es por tanto recomendable sembrar entre la segunda quincena de noviembre y finales del mes de diciembre.

The vegetative growth and productivity of four prickly pear varieties grown under two planting systems (single cladode and double cladode) was evaluated over a period of five years (1995-1999) in the San Juan province of Argentina. The three Argentine varieties examined (possibly ecotypes of the variety known locally as "yellow prickly pear without spines") came from the Santiago del Estero, Córdoba and San Juan provinces. The fourth variety used was "Gialla" from Italy. The double cladode plants reached a greater photosynthetic area and total cladode number than the single cladode plants. The double cladode system produced earlier fruits and the highest yields from the second year onwards. "Gialla" gave the highest fruit yields, and showed the greatest vegetative growth. No differences were observed between the Argentine varieties in terms of yield and plant growth. Planting double cladodes significantly improved fruit production and vegetative growth in the Gialla variety. Most of the fruit produced (80%) by the national varieties fell into the medium (96-140 g) and large (> 140 g) categories, while "Gialla" produced mostly medium and small sized fruits (< 96 g)., El crecimiento vegetativo y la productividad de cuatro variedades de tuna y dos sistemas de implantación, cladodio doble y cladodio simple, fueron evaluados durante cinco años (1995-1999) en la provincia de San Juan (Argentina). La procedencia de tres de las variedades (posibles ecotipos dentro de la variedad conocida localmente como "tuna amarilla sin espinas"), fueron las provincias de Santiago del Estero, Córdoba y San Juan. La restante variedad fue "Gialla", procedente de Italia. Las plantas formadas a partir del sistema cladodio doble presentaron mayor superficie fotosintética y número total de cladodios. Este sistema de implantación ocasionó una entrada anticipada en la etapa productiva y mayores rendimientos a partir del segundo año. "Gialla" superó a las restantes variedades en crecimiento vegetativo y producción. Las variedades nacionales no se diferenciaron en su comportamiento productivo y vegetativo. El efecto del sistema cladodio doble sobre la producción y el crecimiento vegetativo fue significativamente superior en la variedad italiana. La mayor parte de la producción (> 80%) se concentró en las categorías mediana (96 a 140 g) y grande (> 140 g) en las variedades nacionales, y en las categorías mediana y chica (< 96 g) en "Gialla".

This study compares the vegetative growth and productive parameters of non-irrigated Monastrell vines with those under two moderate irrigation treatments. Plant water status and gas exchange parameters were used to evaluate the effect of moderate irrigation on the physiological status of the plants. The predawn and midday leaf water potentials were significantly lower in non irrigated vines, reaching values that indicated severe water stress. Stomatic conductance decreased as the season progressed, especially in non-irrigated vines. This stomata closure resulted in lower net photosynthesis, which affected vegetative growth and productivity. Non-irrigated vines developed a very small canopy and pruning weight together with a very low production compared with irrigated vines. The results demonstrate that the improvement in the physiological status of plants, with moderate irrigation leads to higher yield together with an equilibrium in the vegetative/reproductive growth., Este estudio compara el crecimiento vegetativo y los parámetros productivos de vides Monastrell en secano y otras con dos tratamiento de riego. Para evaluar el efecto del riego en la planta, se midieron los potenciales hídricos al alba y al mediodía y los parámetros de intercambio gaseoso. Los potenciales hídricos fueron significativamente menores en plantas en secano, alcanzando valores que indican un fuerte estrés hídrico. La conductancia estomática decreció al avanzar la estación, especialmente en viñas en secano. El cierre estomático se tradujo en una fotosíntesis neta menor, lo que afectó al desarrollo vegetativo y al rendimiento. Las viñas en secano desarrollaron una masa foliar muy pequeña y un peso de poda muy bajo. Los resultados demuestran que la mejora del estado hídrico de las plantas condujo a producciones mayores y a un correcto balance entre el desarrollo vegetativo y productivo.

In this work, various casing materials (composted pine bark, coconut fibre pith and wood fibre) have been evaluated as alternative to peat (sphagnum blonde peat and black peat) for the cultivation of mushroom. For this, both quantitative (number of mushrooms, yield, unit weight, biological efficiency and earliness) and qualitative (diameter of the sporophore, colour, dry matter, texture, proteins, soluble solids, ash and pH) production parameters were evaluated. The results obtained for the number of mushrooms, unit weight, total production, biological efficiency, diameter of the sporophore, colour, dry matter, protein, soluble solid and ash content, and pH, differed among the three mushroom strains considered. The greatest proportion of harvested mushrooms were of medium size for all strains and casing layers considered. No significant differences were observed in colour and texture among the casing types., En este trabajo se evaluaron diferentes materiales de cobertura (corteza de pino compostada, fibra de coco y fibra de madera) como alternativa a las turbas (turba rubia y turba negra) en el cultivo del champiñón, en cuanto a parámetros de producción cuantitativos (número de champiñones, rendimiento, peso unitario, eficiencia biológica y precocidad) y cualitativos (diámetro del carpóforo, color, materia seca, textura, proteínas, sólidos solubles, cenizas y pH). Los resultados obtenidos en cuanto al número de champiñones, peso unitario, producción total, eficiencia biológica, diámetro del carpóforo, color (L*, DeltaE*), contenidos en materia seca, proteínas, sólidos solubles y cenizas, y pH, han sido dispares en función del experimento (semilla) considerado. En cuanto a la categoría comercial del champiñón cultivado, la mayor proporción correspondió al champiñón mediano, en todos los experimentos y para todas las capas de cobertura consideradas. En cuanto a la precocidad, color (b*) y textura, no se observaron diferencias significativas entre tipos de cobertura en ninguno de los experimentos realizados.

Maize (Zea mays L.) grain endosperm is triploid (3n), of which 2n come from the male (transferred by pollen) and only 1n from the female plant, thus a major impact of the male form can be expected on grain quality parameters. A good example of this relationship is the phenomenon of xenia. The aim of this study was to determine the effect of pollen on grain quality. The field experiment was conducted in 2011; seeds were harvested from eight cultivars: Bosman, Blask, Tur, Kozak, Bielik, Smok, SMH 220 and Kresowiak, derived from free pollination and controlled self-pollination of maize. Analyses of nutrient contents and starch content in the grain were conducted in the laboratory. In addition, 1000 grain weight and the hectoliter weight of all grain samples were recorded. The results confirmed differences in grain quality of maize hybrids obtained by self-pollination and by open pollination. Grain of maize plants obtained by open-pollination was characterised by higher contents of N-free extract and starch, and lower protein content. Undertaking further studies on this subject may indicate specific recommendations for agricultural practice, such as mixtures of hybrids with good combining abilities, which will contribute to improved grain quality without additional costs.

The business dynamics of the agricultural sector generally call for a system of calculation and cost management that goes beyond output assessment and profit determination, and coordinates a tool that supports the decision-making process, thus facilitating the evaluation of different cultivation techniques, varieties and so on. Accordingly, this paper proposes using a cost model based on activities for calculating and managing production costs in multiproduct firms in the agricultural sector, using ornamental plant cultivation as a case in point. This particular case may be considered extremely difficult in terms of crop variety and likely destinations for the products (commercialization, self-supply, etc.). Consequently, the proposed model is transparent, flexible, simple to apply and understand, and easily adaptable to the peculiarities of firms in the agricultural sector in general. Las empresas del sector agrícola requieren un sistema de cálculo y gestión de costes que proporcione información más allá de la simple valoración del producto y de la determinación del resultado, sino que se demanda una herramienta conjunta que ayude en la toma de decisiones y facilite la evaluación de la utilización de diferentes técnicas de cultivos o diferentes variedades. Así, este trabajo propone usar un modelo de coste basado en las actividades para calcular y gestionar los costes de producción de las empresas agrícolas multiproductoras, empleando como caso de estudio el cultivo de plantas ornamentales, por considerarlo de mayor complejidad en términos de productos gestionados y destino de los mismos. El modelo propuesto es transparente, flexible, sencillo de aplicar y entender, y fácilmente adaptable a las características propias de otras empresas del sector agrícola en general.