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Understanding the wavelength dependence of plant responses is essential for optimizing production and quality of indoor plant cultivation. UVA is the main component of solar UV radiation, but its role on plant growth is poorly understood. Here, two experiments were conducted to examine whether UVA supplementation is beneficial for indoor plant cultivation. Lettuce (Lactuca sativa L. cv. "Klee") was grown under mixed blue, red, and far-red light with photon flux density of 237 μmol m−2 s−1 in the growth room; photoperiod was 16 h. In the first experiment, three UVA intensities with peak wavelengths at 365 nm were used: 10 (UVA-10), 20 (UVA-20), and 30 (UVA-30) μmol m−2 s−1, respectively. In the second experiment, 10 μmol m−2 s−1 UVA radiation were given for 5 (UVA-5d), 10 (UVA-10d), and 15 (UVA-15d) days before harvest on day 15, respectively. Compared with control (no UVA), shoot dry weight was increased by 27%, 29%, and 15% in the UVA-10, UVA-20, and UVA-30 treatments, respectively, which correlated with 31% (UVA-10), 32% (UVA-20), and 14% (UVA-30) larger leaf area. Shoot dry weight under the treatments of UVA-5d, UVA-10d, and UVA-15d was increased by 18%, 32%, and 30%, respectively, and leaf area was increased by 15%–26%. For both experiments, UVA radiation substantially enhanced secondary metabolites accumulation, e.g. anthocyanin and ascorbic acid contents were increased by 17%–49% and 47%–80%, respectively. Moreover, plants grown under the UVA-30 treatment were stressed, as indicated by lipid peroxidation and lower maximum quantum efficiency of photosystem II photochemistry (Fv/Fm). We conclude that UVA supplementation not only stimulates biomass production in controlled environments, but also enhances secondary metabolite accumulation. [ABSTRACT FROM AUTHOR]

Biofortification of soybean grains with lithium (Li) is a strategy to improve a food with high social acceptance, in order to promote health benefits. The aim of this work was to evaluate the development of plants and the production of biofortified soybeans with two Li sources. The experiment was conducted in a completely randomized design with five replicates. Ten treatments were obtained in a 2x5 factorial scheme, comprising two sources of Li (LiOH - Li hydroxide and Li2SO4 - Li sulfate) and five doses (0, 30, 60, 90 and 120 mg kg−1) in stages V4 and R1. The supply of Li promoted significant effects (p ≤ 0.05) on the morphology, yield components and nutritional status of soybean plants. The highest grain yield was obtained with the use of Li2SO4 at the estimated dose of 45.7 mg kg−1. The plants accumulated Li between 8.00 and 11.20 mg kg −1, respectively, with the use of Li2SO4 and LiOH. In the grains, the highest concentrations of Li were obtained with the application of 120 mg kg−1. Li2SO4 and LiOH are good sources for biofortification of soybean grains. [ABSTRACT FROM AUTHOR]

Analysing growth and nutrient accumulation is generally employed for guiding the fertilisation practices in the seedling-production chain. In the production of peach rootstock, such evaluations can provide information to aid can to aid in discrimination available genotypes, especially regarding the efficient use and conversion of fertiliser into dry matter, which can reduce the time required to obtain plants suitable for grafting. The aim of this study, was to investigate the differences in growth and nutrient accumulation in three peach-rootstock cultivars. A completely randomised experimental design was used, in a 3 x 4 factorial scheme, including three peach rootstocks ('Flordaguard', 'Capdeboscq' and 'Okinawa Roxo') and four periods of growth evaluation (20, 40, 60 and 80 days after transplanting - DAT), giving a total of 12 treatments, with four replications, one for each plant. The Flordaguard and Capdeboscq cultivars showed greater height and stem diameter as well as a greater accumulation of total dry matter at 80 DAT, and both followed the distribution: leaves (67%) > roots (33%), while total dry-matter production in 'Okinawa Roxo' was less, following the order: leaves (71%) > roots (29%). The rootstock under evaluation showed variations in growth, confirmed by the physiological indices, except for the leaf area and specific leaf area. In general, macronutrient accumulation in the shoots and roots of the cultivars during each growth period was different, suggesting intrinsic differences in each of the genetic materials regarding nutrient demand for maintaining the metabolic processes which are vital to plant growth. [ABSTRACT FROM AUTHOR]

Copyright of Annals of the Polish Association of Agricultural & Agribusiness Economists is the property of Polish Association of Agricultural & Agribusiness Economists and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study is based on establishing soil acidity and fertility of Vertisols after the mineral fertilisers had continuously been applied from 1984 to 2016. The two phosphorus (35 and 70 kg P ha-1), the invariable nitrogen (120 kg N ha-1) and potassium (66.4 kg K ha-1) doses were used in Kragujevac location (central Serbia) for over 33 study years. The impact of fertilisation with mineral fertilisers on soil acidity, organic carbon content, the total N, P and K as well as on P, K forms balance and on some microelements (Fe, Mn, Cu and Zn) availability was studied at soil depths of 0-20 and 20-40 cm. After 33 years, the highest changes were noticed in the surface layer (0-20 cm), with an increase in the acidity level and a decrease in organic carbon content and in the total N. Simultaneously, a higher P and K content and a higher Fe and Mn mobility were established in the same soil layer whereas mineral fertilisers had no significant effect on the changes in chemical properties at 20-40 cm deep soils. [ABSTRACT FROM AUTHOR]

The exchangeable sodium (Na+) in salt affected soils is a major constraint in potassium (K+) availability to plants that disturb ion transport and inhibit plant growth, adversely. Salt tolerant plant growth promoting rhizobacteria (PGPR) may regulate the Na+/K+ efflux and increase K+ uptake by the plant from the soil. Therefore, a pot study was performed to examine the effect of salt tolerant PGPR Bacillus sp. alone and in consortium, on antioxidant enzyme activity, ion uptake and potato (Solanum tuberosum L.) tuber yield in normal and salt affected soils. We observed that Bacillus sp. (strains SR-2-1 and SR-2-1/1) solubilized insoluble phosphorous and produced indole-3-acetic acid while only SR-2-1/1 produced ACC deaminase in culture medium supplemented with various concentrations of NaCl (0–6%). In the pot experiment, the consortium treatment of strains was found to increase relative leaf water contents whereas decreased the electrolyte leakage and antioxidant enzyme activity both in normal and salt affected soils. Similarly, consortium treatment decreased Na+ whereas increased K+, Ca+2, K+/Na+ and Ca+2/Na+ in plant dry matter in both soils. It has been investigated that inoculation of PGPR significantly (p < 0.05) increased plant biomass, number of tubers per plant and tuber weight as compared to un-inoculated plants in both soils. In addition, PGPR inoculation enhanced auxin production in root exudates of young potato plants and bacterial population dynamics in both soils. Na+ ion regulation (R 2 = 0.95) and tuber weight (R 2 = 0.90) in salt affected soil were significantly correlated with auxin production in the rhizosphere. Results of this study conferred that consortium of Bacillus strains (SR-2-1, SR-2-1/1) enhanced auxin production in the rhizosphere of potato plants and that ultimately regulated antioxidant enzyme production and uptake of Na+, K+ and Ca+2 in potato plants resulted into a higher tuber yield in both normal and salt affected soils. • Consortium of Bacillus strains may regulate Na+/K+ efflux and antioxidant activities of potato in salt stress. • Bacillus strains were positive for P-solubilization, IAA and ACC deaminase under NaCl stress. • Consortium inoculation to potato increases RWC while decreases antioxidant enzyme activity and MDA contents. • Consortium inoculation increases auxin production in the rhizopshere which regulate the Na+/K+ uptake and improves tuber yield. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate manganese (Mn) sources and levels effects in irrigated rice production in central Brasil (tropical lowlands of Tocantins state). The experiment was conducted in a 5x5 + 1 factorial scheme, five Mn sources and five levels (0.5; 1.0; 1.5; 2.0; and 2.5 kg ha−1), applied in induction of tillering of rice plants, plus a control without treatment, and Mn content in leaves (mg kg−1), number of panicles per area (m2), hundred grains weight (g), intact grains (%), and grain yield (kg ha−1) were analyzed. Treatments with Mn-carbonate source got the best results and this source at the level of 1.5 kg ha−1 provided the highest yield: 7,375 kg ha−1. Higher values were obtained with the application of 1.0 to 1.5 kg ha−1 of Mn, except for the intact grains where the best means were obtained at 2.5 kg ha−1. [ABSTRACT FROM AUTHOR]

The article presents the spatial differentiation of particulates emission resulting from agricultural production in Poland. Some indicators of emission have been verified and adjusted to the Polish conditions. The paper estimates PM2.5 (particulate matter, aerodynamic diameter less than 2.5 µm) and PM10 (particulate matter, aerodynamic diameter less than 10 µm) emission resulting from agricultural production and agricultural soil. The findings of the research conducted by the Institute of Ecology of Industrial Areas in Katowice in cooperation with the Institute for Chemical Processing of Coal in Zabrze were the main source of those alterations. Data concerning particular sources of emission also come from the information provided by the Central Statistical Office in Warsaw, the Bank of Local Data 2017. The estimation of PM2.5 and PM10 emission was conducted based on the structure of sources of emission resulting from agriculture contained in "EMEP/EEA Emission Inventory Guidebook" in accordance with the Tier 2 method. [ABSTRACT FROM AUTHOR]

Coastal wetlands are projected to experience increases in anthropogenic and climatic disturbances, which may alter plant-sediment feedbacks critical for maintaining marsh resilience to sea level. To study the effects of disturbance on ecogeomorphic processes, we examined aboveground plant responses and sediment accretion in three locations relative to the shoreline (low, mid, and high) within a tidal marsh at Grand Bay National Estuarine Research Reserve, Mississippi, USA. This study site was affected by two hurricanes in the fall of 2008, and subsequently burned as part of a controlled experiment in January 2009, permitting examination of the effects of two disturbance types on aboveground plant responses and vertical accretion. Fire and hurricanes affected these response variables differently, with effects dependent on location within the marsh. Fire significantly reduced standing aboveground biomass, and subsequent recovery of vegetation relative to pre-burn levels was faster in low marsh plots nearest to the shore than in high marsh plots closest to the marsh-pine ecotone. Hurricanes introduced sediment to the marsh platform, resulting in greater accretion in low marsh plots that had more standing biomass and higher stem densities than high marsh plots. Collectively, these results demonstrate that disturbances can heterogeneously affect surface soil-building processes in marshes through effects on sediment and organic matter accumulation, which may have important consequences for surface elevation maintenance in coastal marshes. [ABSTRACT FROM AUTHOR]

Highlights • We identify 7 the most important indicators among 19 variables used. • The energy value of produced biomass was greater than the inputs energy value. • The dependence from non renewable input of Polish farms is bigger than in Italy. Abstract This article concerns the issue of sustainable agriculture, especially in the context of applying the sustainable agricultural indicators. The research was carried out in the period 2002–2004. The aims of this study were the following: a. analysis of farms in northern Poland in the context of sustainable development in the transformation period before accession to the E.U.; b. development of an indicator method for farm evaluation; c. selection of the indicators that most clearly distinguish differences between farms. The farms' assessments were performed by a modification of the Agricultural Performance Indicators' methodology (APIs modified) supported by energy analysis. The indicators were calculated by analysing the following features: Primary Production, Yield Plant Production, Yield Plant Sold, Animal Production, External Renewable Inputs, and Internal Renewable Inputs. The results showed that for the surveyed farms the highest values of renewable inputs from outside the farm used in the production process occurred in mixed farms of up to 40 ha, followed by animal and ecological farms. For all farms the average energy value of produced biomass was only slightly greater than the energy value of the inputs. The indicators of dependence on non-renewable resources clearly showed a higher value compared to Italian farms. The group of ecological farms obtained the highest autonomy indicator value (53%). The indicator of overall sustainability showed that the contribution of agriculturally-generated external input was at levels ranging from 14% to 66% of total input. The features and indicators that most significantly differentiated the study group of farms were Yield Plant Sold, Indicator of Primary Production to the Internal Input, Indicator of Sales to the Input from Non-Renewable Sources of Energy, Indicator of Sales to the Overall External Input, Indicator of Primary Production to the Overall Energy Input, Indicator of Primary Production to the External Non-Renewable Input, and Yield Plant for Fodder. [ABSTRACT FROM AUTHOR]

Fertilization is a common management measure for the restoration of degraded grasslands. In order to investigate whether fertilization can improve the severely degraded alpine meadows, we conducted a fertilization experiment on the Tibetan Plateau that began in 2008. The treatments were nitrogen (N) addition alone (50 kg N ha−1 year−1 , LN; 100 kg N ha−1 year−1 , HN) or combined with phosphorus (P) fertilizer [(50 kg N + 50 kg P) ha−1 year−1 , LN+P; (100 kg N + 50 kg P) ha−1 year−1 , HN + P] in a severely degraded alpine meadow. Eleven consecutive years of N and P fertilization did not significantly change plant species richness, while fertilization reduced the plant species diversity index, with the most significant reduction in HN and HN + P treatments. LN + P and HN + P treatments greatly increased community coverage and aboveground biomass, while N addition alone, especially the HN treatment, significantly reduced community coverage and aboveground biomass. Fertilization had no effect on edible pastures, while N and P fertilization significantly increased the biomass of forbs. The proportion of forbs to total aboveground biomass was more than 90%, and fertilization had no effect on this proportion. This shows that forbs still have an absolute advantage in the community. In addition, HN, LN + P, and HN + P treatments significantly reduced ecosystem stability. Community aboveground biomass was greatly enhanced in the N and P fertilization treatments, and this was beneficial for the ecosystem quality and soil hydrological functioning. However, fertilization treatments did not improve the community structure with either N addition alone or combined with P fertilizer, which was of little significance in providing forages for the sustainable development of livestock husbandry. To improve the structure of severely degraded alpine grasslands, it is necessary to combine other measures such as cutting the roots of forbs, fencing, or reseeding. [ABSTRACT FROM AUTHOR]

In order to decrease the concentration of toxic metals in contaminated lands, phytoextraction can be suitable considering the use of plant species with high potential for biomass production, such as biomass sorghum (Sorghum bicolor L.). We assessed a biomass sorghum (BRS716) potential as a copper phytoextractor as well as the physiological stability under this stressful condition. A completely randomized experimental design was used for a greenhouse experiment in which sorghum plants were submitted to a range of Cu2+ concentrations: 2.3, 10.9, 19.6, 30.5, 37.6 and 55.6 mg dm−3. The plant growth was not affected by increasing Cu2+ concentrations, suggesting that this species is tolerant to copper. There was a decrease in photosynthetic rate according to the increase in Cu2+ concentration, but not at a level that could disturb plant metabolism and eventual death. The values obtained for transfer index ranged from 0.62 to 0.11 which evidenced the restriction of Cu2+ transport to the aerial parts. The more Cu2+ available in soil, the smaller the amount of Cu2+ transported to aerial parts of sorghum. So, our results show that biomass sorghum has potential to be used for Cu2+ phytoextraction in concentration of up to 20 mg dm−3. Also, in heavily Cu2+ polluted sites, it can be used to produce biomass for bioenergy purpose, promoting a low rate of Cu2+ extraction. [ABSTRACT FROM AUTHOR]

Copyright of Ecological Engineering / Inżynieria Ekologiczna is the property of Polish Society of Ecological Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Burning and mowing are two of the most common grassland disturbances across millions of hectares worldwide, but uncertainty remains about when and why these disturbances increase plant production. One of the main hypotheses for increased plant production is that disturbances increase soil temperature in the early growing season and thereby increase plant growth. I tested this hypothesis using a multi-decade study of the frequency (annual or quadrennial) and season (spring, summer, or autumn) of reconstructed tallgrass prairie burning and mowing. To determine plant production, I measured above-ground biomass during three periods of the 2015 growing season: (1) prior to mid-May; (2) mid-May to early July; and (3) early July to the end of the growing season in late September. I also measured soil temperatures from May 2014 to January 2016. This unique dataset allows a detailed picture of when burning and mowing are increasing plant production and whether these increases are likely caused by soil temperatures. I found that, compared to other treatments, autumn burning and mowing similarly increased plant production from the beginning of the growing season to mid-May (autumn disturbances increased production from 37 to 77 g/m2) and, compared to other treatments, both autumn and spring burning and mowing similarly increased plant production from mid-May to early July (autumn and spring disturbances increased production from 363 to 439 g/m2). Mowing had little effect on soil temperature but burning increased average daily maximum soil temperature at 2.5 cm depth by 6.4°C in the month after burning. Overall, these results suggest that burning did not increase early growing season plant production due to increased soil temperature, given that mowing similarly affected plant production but did not similarly affect soil temperature. I explore alternate explanations for changes in plant production, including increased light and nutrient availability, and decreased detritus. [ABSTRACT FROM AUTHOR]

Grazing and clipping defoliation are the most important human disturbances in natural grasslands. Compensatory growth is a common response to clipping defoliation, which is of great significance for forage production and livestock husbandry development. However, how clipping intensity affects plant compensatory growth and how nitrogen (N) addition regulates this response in alpine ecosystems are still unclear. A manipulative experiment including two clipping intensities (light and heavy) crossed with N addition was conducted in an alpine meadow ecosystem to examine the effects of how N addition regulated plant compensatory growth induced by clipping defoliation. Selective clipping was used to simulate animal feeding, that is, only grasses and sedges were clipped. Under the N addition treatment, the relative growth rate of grasses and total biomass after clipping were significantly higher than those under the no N addition treatment. The total community biomass showed over‐compensatory growth in light clipping under N addition treatment, while it showed equal‐compensatory growth under the other treatments. The over‐compensatory growth in light clipping under the N addition treatments mainly resulted from the stimulated growth of grasses. Regression analysis showed that the relative growth rate and biomass of grasses were positively correlated with soil inorganic N content, but increasing N availability was not conducive to the growth of sedges and other forbs. Divergent responses of different plant functional groups to clipping and N addition would lead to changes in community structure and functioning. Both community biomass and compensatory growth tended to increase first and then reach a stable state with the increase in soil N availability. Our results show that although light clipping could largely stimulate forage production under N addition, excessive clipping cannot lead to a continuous increase in compensatory growth of plant biomass, even under N addition conditions, in this semiarid alpine meadow ecosystem. [ABSTRACT FROM AUTHOR]

In many circles, brown coal continues to be viewed as a cheap source of energy, resulting in numerous investments in new opencast brown coal mines. Such a perception of brown coal energy is only possible if the external costs associated with mining and burning coal are not considered. In past studies, external cost analysis has focused on the external costs of coal burning and associated emissions. This paper focuses on the extraction phase and assesses the external costs to agriculture associated with the resulting depression cone. This paper discusses the difficulties researchers face in estimating agricultural losses resulting from the development of a depression cone due to opencast mineral extraction. In the case of brown coal, the impacts are of a geological, natural-climatic, agricultural-productive, temporal, and spatial nature and result from a multiplicity of interacting factors. Then, a methodology for counting external costs in crop production was proposed. The next section estimates the external costs of crop production arising from the operation of opencast mines in the Konin-Turek brown coal field, which is located in central Poland. The analyses conducted showed a large decrease in grain and potato yields and no effect of the depression cone on sugar beet levels. Including the estimated external costs in the cost of producing electricity from mined brown coal would significantly worsen the profitability of that production.

In this paper is shown a description of the application based on the latest web technologies for optimal greenhouse production system selection. Web application is based on pre-formed expert model implemented in the web application with parameters stored in a database for easy maintenance. Using latest web technologies is achieved massive scale and availability of such expert knowledge to anyone with the Internet access and with standard web browser. The application in a very intuitive way to an agricultural producer, based on his initial idea and implemented expert model, guides throughout the process of selecting the optimal greenhouse production system and system parameters.

Introduction. Residues of previous crops provide a valuable amount of organic matter that can be used either to restore soil fertility or for external use. A better understanding of the impact of crop residue management on the soil-water-plant system is needed in order to manage agricultural land sustainably. This review focuses on soil physical aspects related to crop residue management, and specifically on the link between soil structure and hydraulic properties and its impact on crop production. Literature. Conservation practices, including crop residue retention and non-conventional tillage, can enhance soil health by improving aggregate stability. In this case, water infiltration is facilitated, resulting in an increase in plant water availability. Conservation practices, however, do not systematically lead to higher water availability for the plant. The influence of crop residue management on crop production is still unclear; in some cases, crop production is enhanced by residue retention, but in others crop residues can reduce crop yield. Conclusions. In this review we discuss the diverse and contrasting effects of crop residue management on soil physical properties and crop production under a temperate climate. The review highlights the importance of environmental factors such as soil type and local climatic conditions, highlighting the need to perform field studies on crop residue management and relate them to specific pedo-climatic contexts.

Indoor vertical farming offers great opportunities regarding a sustainable and consistent production of high-quality herbs and raw materials all year round for the perfume, chemical, or food industry. Cultivation takes place in an enclosed structure, operating predominantly independent from external conditions in multi-layer systems equipped with artificial lighting, enabling extremely high resource use efficiencies with a simultaneous increase in yield. On the other hand, field production in terms of plant quality and harvesting times is highly influenced by environmental conditions, making it difficult to maintain homogenous raw material qualities throughout the year. To show how different light qualities affect the overall efficiency and quality of Origanum majorana grown in an indoor farm, the resource consumption, yield, and cultivation time as well as the essential oil quantity was analyzed, and the efficiencies in terms of energy and land use efficiency calculated. The experimental setup clearly demonstrated that the yield regarding fresh as well as dry matter and oil content was comparable to one square meter of open field production. Based on this, the multi-layer system and the noticeable lowered growth period result in a significantly higher area efficiency compared to the open field, leading to a potential increase of annual yields of dried leave weight and oil contents by up to 21 times. It was also shown that a white spectrum (W) showed similar influence on plant growth and yield as a spectrum consisting of blue and red (B/R). Nevertheless, the LED treatment W did show higher light use efficiencies as well as a better working conditions inside the cultivation chamber. By an integration of indoor vertical farming into existing industrial processes, new and innovative opportunities for a flexible and low-risk supply chain seem feasible and according to German food industry meet the interests of existing stakeholders.

Arbuscular mycorrhizal (AM) fungi have become an attractive target as biostimulants in agriculture due to their known contributions to plant nutrient uptake and abiotic stress tolerance. However, inoculation with AM fungi can result in depressed, unchanged, or stimulated plant growth, which limits security of application in crop production systems. Crop production comprises high diversity and variability in atmospheric conditions, substrates, plant species, and more. In this review, we emphasize that we need integrative approaches for studying mycorrhizal symbioses in order to increase the predictability of growth outcomes and security of implementation of AM fungi into crop production. We briefly review known mechanisms of AM on nutrient uptake and drought tolerance of plants, on soil structure and soil hydraulic properties. We carve out that an important factor for both nutrient availability and drought tolerance is yet not well understood; the AM effects on soil hydraulic properties. We gave special emphasis to circular references between atmospheric conditions, soil hydraulic properties and plant nutrient and water uptake. We stress that interdisciplinary approaches are needed that account for a variability of atmospheric conditions and, how this would match to mycorrhizal functions and demands in a way that increased plant nutrient and water uptake can be effectively used for physiological processes and ultimately growth. Only with integrated analyses under a wide range of growing conditions, we will be able to make profound decisions whether or not to use AM in particular crop production systems or can adjust culture conditions in ways that AM plants thrive.

This review paper describes a novel approach to plant cultivation under soil-less culture. At present, global climate change is expected to raise the risk of frequent drought. Agriculture is in a phase of major change around the world and dealing with serious problems. In future, it would be difficult task to provide a fresh and clean food supply for the fast-growing population using traditional agriculture. Under such circumstances, the soil-less cultivation is the alternative technology to adapt effectively. The soil-less system associated with the Hydroponic and Aeroponics system. In the aeroponics system, plant roots are hanging in the artificially provided plastic holder and foam material replacement of the soil under controlled conditions. The roots are allowed to dangle freely and openly in the air. However, the nutrient rich-water deliver with atomization nozzles. The nozzles create a fine spray mist of different droplet size at intermittently or continuously. This review concludes that aeroponics system is considered the best plant growing method for food security and sustainable development. The system has shown some promising returns in various countries and recommended as the most efficient, useful, significant, economical and convenient plant growing system then soil and other soil-less methods. [ABSTRACT FROM AUTHOR]

The productivity of upland rice increases with the number of plants per unit area to the point where intraspecific competition for nutrients, water, light and other factors of production limits the productive process. The objective of this work was to evaluate the effect of spacing on the production of highland rice irrigated in the brazilian savannas. The experiment was conducted from May to October of the year 2015 in Goianésia - GO, in the experimental area of the Evangelical Faculty of Goianésia. The BRS Primavera variety was tested in four spacings (20, 30, 40 and 50 cm) between rows and density of 100 seeds per meter and used as sprinkler irrigation. The experimental design was in randomized blocks, with four treatments with three replicates. The results showed that the spacing of 30 cm between rows provided higher productivity in the BRS Primavera variety. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi have become an attractive target as biostimulants in agriculture due to their known contributions to plant nutrient uptake and abiotic stress tolerance. However, inoculation with AM fungi can result in depressed, unchanged, or stimulated plant growth, which limits security of application in crop production systems. Crop production comprises high diversity and variability in atmospheric conditions, substrates, plant species, and more. In this review, we emphasize that we need integrative approaches for studying mycorrhizal symbioses in order to increase the predictability of growth outcomes and security of implementation of AM fungi into crop production. We briefly review known mechanisms of AM on nutrient uptake and drought tolerance of plants, on soil structure and soil hydraulic properties. We carve out that an important factor for both nutrient availability and drought tolerance is yet not well understood; the AM effects on soil hydraulic properties. We gave special emphasis to circular references between atmospheric conditions, soil hydraulic properties and plant nutrient and water uptake. We stress that interdisciplinary approaches are needed that account for a variability of atmospheric conditions and, how this would match to mycorrhizal functions and demands in a way that increased plant nutrient and water uptake can be effectively used for physiological processes and ultimately growth. Only with integrated analyses under a wide range of growing conditions, we will be able to make profound decisions whether or not to use AM in particular crop production systems or can adjust culture conditions in ways that AM plants thrive. [ABSTRACT FROM AUTHOR]

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water is known as a critical and rare source that humans and ecological systems depend on. With growing population and developing technologies in many countries, availability to this critical source has been decreased. This research was conducted in a split plot experiment in a randomized complete block design with 3 replications in Iran (the north of Iran, Astaneh-ye-Ashrafiyeh). The main treatments were irrigation with 40, 60, 80 and 100% water requirement using water balance and direct method and the second treatments were 0 and 30, 60 and 90 kg N ha-1, and two bean cultivars were tested (local Dehsari and Cowpea). Seed yield in 2016 and 2017, in the case of irrigation with100% water requirement and 60 kg N ha-1 was higher in common bean cultivar than in Cowpea and yields were 3486 and 3646 kg ha-1, respectively. The highest water use productivity in seed yield in 2016 and 2017 was in common bean cultivar, and in the case of irrigation with 100% water requirement and 60 kg N ha-1 fertilizer added, levels were 0.70 and 0.69 kg m-3, respectively. [ABSTRACT FROM AUTHOR]

Greenhouse production of poinsettia calls for strict control of morphological parameters, which may be achieved through the use of chemical growth retardants. Use of such chemicals is becoming restricted thus alternative methods for growth control are needed. Here the effects of UV radiation were tested on Euphorbia pulcherrima (Willd ex. Klotzch) in controlled environment under moderate (60%) and high (90%) relative air humidity (RH), to determine the potential to control plant morphology. Vegetative plants (‘Christmas Feelings’) received UV during the dark period, while two generative cultivars, one strong growing phenotype ‘Infinity Red’ (‘IR’) and one more compact phenotype ‘Bravo Bright Red’ (‘BBR’), received UV at the end of the light period (EOD). The morphology of vegetative plants was mainly affected by RH rather than UV radiation. Generative plants were also strongly affected by RH, though both cultivars showed reduced plant diameter, shoot biomass, leaf area, and bract area when exposed to UV, as well as increased leaf chlorophyll content, though responses to UV were stronger in moderate RH compared to high RH. Transpiration of leaves and bracts was mainly affected by RH not UV, and photosynthesis and production time were not affected by either RH or UV. We conclude that UV radiation is a potential tool to grow more compact plants, though its effects are partially determined by the aerial environment. [ABSTRACT FROM AUTHOR]

Copyright of Annals of the Polish Association of Agricultural & Agribusiness Economists / Roczniki Naukowe Stowarzyszenia Ekonomistow Rolnictwa & Agrobiznesu is the property of Polish Association of Agricultural & Agribusiness Economists and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lignocellulosic biomass derived from energy crops, a renewable energy source, must be boosted in order to mitigate climate change effects. For this reason, vegetative growth and biomass production of Eucalyptus x urograndis , under a Mediterranean climate, was studied for three years. At the second and the third planting years, 12 treatments were applied combining four irrigation levels during the dry season (0, 325, 646 and 1298 mm of water per year, plus 418 mm of average rainfall) and three fertilisation amounts (0, 150 and 300 kg ha −1 of N per year with a nutrient balance of 16-8-12 [2 MgO, 12 SO 3 , 2.6 CaO]). A seasonal growth monitoring of height and diameter was carried out along with dry biomass production and assessment of soil properties before and after of the trial was carried out. Irrigation and fertilisation significantly increased aboveground biomass production, averaging 20.6–55.4 t ha −1 per year; the combined treatments 0 mm−0 kg ha −1 of N and 1298 mm–300 kg ha −1 of N were the least and the most productive, respectively. The data constitute a useful resource for the adjustment of the optimal irrigation (≥1500 mm per year of rainfall plus irrigation) and fertilisation doses (≥150 kg ha −1 of N) applied to plantations, as well as the management of crops to design a sustainable productive system that allows the preservation or improvement of soils. The energy and physical-mechanical biomass properties together with the derived pellets were of high quality, and they show promise for industrial boiler use. [ABSTRACT FROM AUTHOR]

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Following the obligatory implementation of integrated pest management in the European Union (EU), the plant protection means suitable for application in organic agriculture attracted the attention of quite a wide group of potential users. In spite of the common rules of organic production, as well as the uniform principles of placing plant protection products on the market, the availability of products that can be legally used in organic crop protection differs significantly among the Member States. There is a uniform list of 10 basic substances that can be used in the protection of organic crops throughout the entire EU. Twelve Member States have official registers of plant protection products for use in organic agriculture, and the total number of qualified products per country varies from11 in Lithuania to 576 in Italy. Some products that improve plant vigour or resistance andmay be of use in protection of organic crops are placed on the market as biostimulants. They fall under the law that governs fertilisers and the systems of their registration vary widely among the Member States. In addition, there exist a number of products that have been legally introduced onto the markets of some Member States without registration as a consequence of a loophole in the law. The use of unregistered products in organic agriculture raises some doubts, but currently it seems that there is no legal basis on which to explicitly prohibit the practice. [ABSTRACT FROM AUTHOR]

In many water-scarce countries, waste water is used for irrigation which poses a health risk to farmers and consumers. At the same time, it delivers nutrients to the farming systems. In this study, we tested the hypotheses that biochar can be used as a filter medium for waste water treatment to reduce pathogen loads. At the same time, the biochar is becoming enriched with nutrients and therefore can act as a fertilizer for soil amendment. We used biochar as a filter medium for the filtration of raw waste water and compared the agronomic effects of this “filterchar” (FC) and the untreated biochar (BC) in a greenhouse pot trial on spring wheat biomass production on an acidic sandy soil from Niger. The biochar filter showed the same removal of pathogens as a common sand filter (1.4 log units on average). We did not observe a nutrient accumulation in FC compared to untreated BC. Instead, P, Mg and K were reduced during filtration while N content remained unchanged. Nevertheless, higher biomass ( Triticum L. Spp.) production in BC (+72%) and FC (+37%) treatments (20 t ha −1 ), compared with the unamended control, were found. There were no significant differences in aboveground biomass production between BC and FC. Soil available P content was increased by BC (+106%) and FC (+52%) application. Besides, mineral nitrogen content was reduced in BC treated soil and to a lesser extent when FC was used. This may be explained by reduced sorption affinity for mineral nitrogen compounds on FC surfaces. Although the nutrients provided by FC decreased, due to leaching in the filter, it still yielded higher biomass than the unamended control. [ABSTRACT FROM AUTHOR]

Agriculture is the closest branch to natural ecosystems by the type of substance-energy relations. That is why the search for forms of its management (specialization) which would correspond to natural opportunities of a certain territory is the main task. Its solution will promote balanced environmental use in the agricultural sphere. Cherkasy Oblast belongs to the region in which a considerable part of agricultural production of Ukraine is produced. Therefore, an important problem is the definition of areas in which the impact of agriculture is an environmental hazard. Our research is aimed at it. The harmful effect on the soil of certain combinations of branches within each farm was determined. Based on information on the cultivation of crops by enterprises of Cherkasy Oblast, a method was developed for assessing the degree of environmental impact of both individual crops and their combinations. Zoning of territories by specialization (agricultural areas) and environmental impact is carried out. Application of this methodology has made it possible to establish that the current state of agricultural land use in the region does not meet requirements of rational nature management. Excessive load on soils in the process of agriculture led to the intensification of erosion processes which was facilitated by the unjustified increase in cultivated crops, in soil-exhausting sunflower and rape. For many decades, the extensive use of lands (especially arable lands) was not offset by equivalent measures for the reproduction of soil fertility and its rational use. According to the results, ways of reducing the harmful environmental impact of agricultural enterprises of Cherkasy Oblast are proposed. [ABSTRACT FROM AUTHOR]

Decades of grazing studies have identified a number of key plant and soil processes affected by large herbivores and how those grazer effects vary among different grassland types. However, there remains little mechanistic understanding about how the effects of grazers on plants and soils may be biogeochemically linked in regulating grassland processes., Here we measured monthly plant and soil variables, including soil moisture, soil nitrogen (N) availability, plant biomass, shoot N concentration and plant production, in grazed and ungrazed (fenced) grasslands during the 2012-2014 growing seasons. Measurements were used to assess direct and indirect biogeochemical pathways by which grazers influenced net above-ground plant production ( NAP) in dry and mesic grasslands in Yellowstone National Park ( YNP)., Herbivores only had direct effects on plant variables at the dry grassland compared to direct and indirect effects on both plant and soil variables at the mesic grassland. By enhancing leaf N content at both grasslands, grazers shifted the resource controlling NAP from N in ungrazed grassland to moisture, and potentially phosphorus and/or other soil nutrients, in grazed grassland., Synthesis. These results indicate the mechanistic linkage between top-down (herbivore) and bottom-up (soil resource) control of grassland production. Changing the resources that limit net above-ground plant production ( NAP) likely has a profound impact on how grazed vs. ungrazed Yellowstone National Park ( YNP) grasslands respond to environmental (e.g., climate, atmospheric N deposition) variability. Because grazing enhances leaf N among many types of grasslands, increasing the sensitivity of plant production to the availability of moisture and nutrients other than N may be a general response of grasslands to grazing. [ABSTRACT FROM AUTHOR]