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Gray mold caused by Botrytis cinerea is an important disease in strawberries. This fungus causes significant economic losses since it attacks plants and fruits. In this context, this work aimed to evaluate the effectiveness of Acibenzolar-S-methyl (ASM) and Harpin protein in pre- and post-harvest as inducers of resistance in strawberries to B. cinerea. Strawberry plants (Fragaria x ananassa) from ‘Aromas’ and ‘Camarosa’ cultivars were grown in greenhouse and evaluated in laboratory. Doses of Harpin and ASM in pre- and post-harvest applications were assessed. Yield parameters of strawberry, B. cinerea incidence and injured area in fruit, fruit firmness, CO2 assimilation rate, and phenylalanine ammonia-lyase (PAL) activity were analyzed. Elicitors application in pre- and post-harvest conditions promoted a decrease of B. cinerea incidence and injured area in strawberry fruits. The results suggest that Harpin and ASM treatment show a significant impact on strawberry fruit disease. The control may be associated with the PAL induction, responsible for inducing defense responses. Harpin and ASM represent a promising alternative to synthetic fungicides for B. cinerea control during post-harvest storage.

Yerba mate (Ilex paraguariensis) has both economic and cultural importance in South America. However, due to a lack of quality control during processing, adulteration can occur. The aim of the study was to measure adulteration of yerba mate brands marketed in southern Brazil with sucrose, through isotopic characterization. Fifteen brands from local grocery stores were analyzed using eight samples of yerba mate derived from plants of different environments. Five samples of other species of Ilex genus and Ligustrum japonicum, which commonly contaminate yerba mate, were also tested. The isotopic composition of C (δ13C) and % N pointed out that some brands may have been adulterated with sucrose and a combination of % N and δ15N may be sufficient to identify contamination by leaves from other species. This study shows that isotopic characterization can potentially identify yerba mate that is adulterated with sucrose, and this method can also be used for quality control in food industry and to warrant further investigation.

Toward improving reforestation of Brazilian pine (Araucaria angustifolia), two contrasting sapling sizes in either full sun or in the shade of a mixed plantation and the effect of opening the canopy were evaluated for survival, growth, gas exchange, photosynthetic pigments, and leaf anatomy 18 months after being planted. At 23 months after planting, a partial opening was made in the canopy in the mixed plantation, then the saplings were evaluated again after 2 months for the same morphophysiological traits. After 18 months, saplings planted in the full sun had higher survival, growth, pigments, and photosynthesis compared to the shaded saplings. Large saplings had higher survival and growth compared to the small ones. Shaded leaves were thinner and little differentiation of palisade parenchyma and hypodermis. After opening of the canopy, photosynthetically active radiation was 10 times higher, and the saplings quickly grew in height due to increased photosynthesis. Thus, although the species can tolerate shade, growth in the shade is limited. We recommend that for reforestation purposes of Brazilian pine, large saplings should be selected and planted in the open for better development.

Artemisia annua L. is the main artemisinin source, a sesquiterpene lactone used in the treatment against cancer and malaria, whose demand is high and the costs involving its production must be feasible. The main objective of the present work was to define a industrially and economically viable technology to obtain artemisinin. The experimental conditions of temperature, pressure and co-solvent use for obtaining extracts enriched in artemisinin by supercritical fluid extraction (SFE) were investigated, and an economic evaluation of the SFE was performed in comparison with the conventional extraction using ethanol. The techno-economic analysis showed that among the conditions evaluated in the present study, SFE at 60 °C and 250 bar, without co-solvent, was the most promising production condition. Nevertheless, for the commercial viability of the arteminisin extraction using SFE it is indicated to use A. annua rigorously selected, and to reduce costs of raw material.

Galling insects gain food and shelter by inducing specialized anatomical structures in their plant hosts. Such galls often accumulate plant defensive metabolites protecting the inhabiting insects from predation. We previously found that, despite a marked natural chemopolymorphism in natural populations of Pistacia palaestina, the monoterpene content in Baizongia pistaciae-induced galls is substantially higher than in leaves of their hosts. Here we show a general up-regulation of key structural genes in both the plastidial and cytosolic terpene biosynthetic pathways in galls as compared with non-colonized leaves. Novel prenyltransferases and terpene synthases were functionally expressed in Escherichia coli to reveal their biochemical function. Individual Pistacia trees exhibiting chemopolymorphism in terpene compositions displayed differential up-regulation of selected terpene synthase genes, and the metabolites generated by their gene products in vitro corresponded to the monoterpenes accumulated by each tree. Our results delineate molecular mechanisms responsible for the formation of enhanced monoterpene in galls and the observed intraspecific monoterpene chemodiversity displayed in P. palaestina. We demonstrate that gall-inhabiting aphids transcriptionally reprogram their host terpene pathways by up-regulating tree-specific genes, boosting the accumulation of plant defensive compounds for the protection of colonizing insects.

The aim of this study was to compare two methods of estimating leaf area (leaf area meter LI-COR 3100 and ImageJ software) in oats. Renascem black oats and UTF Iguaçu white oats cultivars were evaluated. All the leaves of one plant per plot, with six repetitions, were evaluated every seven days to obtain five assessments for each cultivar. The leaves were identified and fixed on a white A4 sheet of paper with an indication of a known area (45 cm²), photographed and evaluated using a leaf area meter (LI-3100 - LI-COR). Leaf area was then estimated using ImageJ software. Estimates were obtained for standard deviation and coefficient of variation, and a simple linear regression equation was estimated based on the two estimation methods. Mean variances were tested using the ‘F’-test and the means compared by the ‘t’-test. There was no difference between the leaf areas found by both methods. In addition, they were highly correlated, and variances were homogeneous. We concluded that ImageJ software can be used instead of the leaf area meter on the two oat cultivars evaluated.

Yield increase in soybean [Glycine max (L.) Merr.] has occurred due to plant breeding, as well as the improvement in management practices. Genetic gain for important traits in soybean due to plant breeding in South Brazil has not been evaluated. The objective of this study was to measure the genetic progress of several soybean agronomic, phenological and physiological traits, in a historical set of cultivars released for cultivation in South Brazil from 1965 to 2011. Twenty-nine cultivars were evaluated in a three replicate randomized complete block design at two locations in the 2016/17 crop season. Mean genetic gain for yield was 40.06 kg ha−1 year−1 averaged across locations. The modern cultivars had higher biological yield (BY), harvest index (HI), number of pods per plant (NPP), and lower number of branches per plant, plant height, and lodging score compared to older releases. There was a reduction in the vegetative period, and increase in ratio between reproductive and vegetative periods (R/V). Photosynthetic rate (PN) and transpiration rate (Tr) also increased with year of release. The traits BY, NPP, HI, R/V, number of seeds per pod, PN, Tr, and chlorophyll content (Chl a and b) was highly associated with seed yield. Breeding strategies that maximize the R/V ratio, and prioritize indirect selection through HI, BY, NPP, PN, Tr, and Chl a and b, will likely contribute to improving soybean yield in the future.

The objective of this study was to evaluate the effect of acibenzolar-S-methyl (ASM) and harpin protein, applied pre-harvest, in the induction of resistance in strawberry to pathogens and mites. The experiment was conducted in a greenhouse, in a randomized block design with three replications. Treatments with harpin protein and ASM were established through biweekly applications of these elicitors in plants of strawberry, from 60 to 120 days after transplanting of seedlings. The application of ASM and harpin protein induced resistance in the strawberry plants, resulting in an increase in phenylalanine ammonia-lyase activity and total phenol production, while reducing leaf blight and grey mould. The application of harpin protein also caused a reduction in mite damage, while increasing photosynthetic rate and the production of marketable fruits. The elicitors ASM and harpin, applied pre-harvest, can be used as part of the integrated pest management of diseases and pests of strawberry.

Varronia curassavica Jacq. is a native medicinal plant from Brazil, its anti-inflammatory, analgesic and healing properties are mainly due to the presence of α-humulene and β-cariophyllene on the essential oil extracted from the leaves. The study aimed to evaluate parameters related to the production, harvest and extraction and their effects on the quality/quantity of the V. curassavica essential oil under field conditions. For the drying experiment it was used natural drying in greenhouse and an artificial one with forced ventilation using the temperature of 40 °C until constant weight with six replications per treatment. For the harvest daytime experiment, five harvest different times were evaluated (6 a.m., 9 a.m., 12 p.m., 3 p.m., 6 p.m.) with five replications per treatment. In both experiments it was used the completely randomized design. The effect of two natural elicitors on the sesquiterpene content of V. curassavica was also evaluated, where field grown plants received the application of acibenzolar-S-methyl (500 mg/L), 1,6 β- d -glucan obtained from Lasiodiplodia theobromae (50 mg/L) and distilled water as a control, where gas exchange rate, terpene enzymes such as phenylalanine ammonia-lyase, superoxide dismutase, guaiacol peroxidase and catalase activity and essential oil content in leaves were measured. The exhaustion time for the extraction of the V. curassavica essential oil by hydrodistillation was determined for whole and ground leaves. To evaluate and compare the extraction techniques performance, it was used a conventional and a green technology, it was evaluated the essential oil yield and α-humulene content in the volatile oil. Finally, a study of economic viability of the implantation of an agroindustry to obtain V. curassavica essential oil was performed using Expanded Multi-index Methodology (EMIM). The essential oil yielding was determined through hydrodistillation, using a Clevenger device, and the essential oil quality was measure by Gas Chromatography. There was not statistical difference between the drying methods tested regarding the essential oil production but the highest values of α-humulene and β-caryophyllene were obtained when artificial drying at 40 °C was adopted. It is possible to indicate a harvesting daytime around 11–12 a.m., resulting not only in higher yield of essential oil but also a higher content of the desired anti-inflammatory compounds. The acibenzolar-S-methyl reduced significantly the net carbon assimilation rate and the intercellular CO2 concentration, while1,6 β- d -glucan reduced significantly only the intercellular CO2 concentration. The essential oil analysis reveals that elicitation was not efficient to increase the yield of V. curassavica essential oil or to change relative rate among the oil chemical constituents, especially α-humulene and β-caryophyllene. The determined exhaustion time was 1.5 h for both treatments, and the conventional extraction technology (steam distillation) is the best option for extraction of the essential oil. At last, according to the economic study, it is recommended the implementation of the investment project.

Commercial Artemisia annua crops are the sole source of artemisinin (ART) worldwide. Data on seasonal accumulation and peak of sesquiterpenes, especially ART in commercial A. annua, is lacking while current breeding programs focus only on ART and plant biomass, but ignores dihydroartemisinic acid (DHAA) and artemisinic acid (AA). Despite past breeding successes, plants richer in ART are needed to decrease prices of artemisinin-combination therapy (ACT). Our results show that sesquiterpene concentrations vary greatly along the growing season and that sesquiterpene profiles differ widely among chemotypes. Field studies with elite Brazilian, Chinese, and Swiss germplasms established that ART peaked in vegetative plants from late August to early September, suggesting that ART is related to the photoperiod, not flowering. DHAA peaks with ART in Chinese and Swiss plants, but decreases, as ART increases, in Brazilian plants, while AA remained stable through the season in these genotypes. Chinese plants peaked at 0.9% ART, 1.6% DHAA; Brazilian plants at 0.9% ART, with less than 0.4% DHAA; Swiss plants at 0.8% ART and 1% DHAA. At single-date harvests, seeded Swiss plants produced 0.55-1.2% ART, with plants being higher in DHAA than ART; Brazilian plants produced 0.33-1.5% ART, with most having higher ART than DHAA. Elite germplasms produced from 0.02-0.43% AA, except Sandeman-UK (0.4-1.1% AA). Our data suggest that different chemotypes, high in ART and DHAA, have complementary pathways, while competing with AA. Crossing plants high in ART and DHAA may generate hybrids with higher ART than currently available in commercial germplasms. Selecting for high ART and DHAA (and low AA) can be a valuable approach for future selection and breeding to produce plants more efficient in transforming DHAA into ART in planta and during post-harvest. This novel approach could change the breeding focus of A. annua and other pharmaceutical species that produce more than one desired metabolite in the same pathway. Obtaining natural variants with high ART content will empower countries and farmers who select, improve, and cultivate A. annua as a commercial pharmaceutical crop. This selection approach could enable ART to be produced locally where it is most needed to fight malaria and other parasitic neglected diseases.

Understanding the processes responsible for genetic progress in grain yield and relating them to the growth and developmental phases of the wheat plant are essential for improving yield potential. This study aimed to evaluate the duration of developmental phases and eco-physiological traits associated to grain yield in Brazilian wheat cultivars released in different decades. Wheat cultivars released from 1940 to 2009 were evaluated during 2010 and 2011 in Pato Branco, Parana, Brazil. The length of the following periods was compared: sowing-emergence (SW-EM), emergence-double ridge (EM-DR), double ridge-terminal spikelet (DR-TS), terminal spikelet-anthesis (TS-ANT), anthesis-physiological maturity (ANT-PM), sowing-anthesis (SW-ANT) and sowing-physiological maturity (SW-PM). Yield components were also measured. Breeding has reduced the days until anthesis by 14.2%, while it has extended the grain-filling period by 7.6%, compared to the first cultivars released in the country, thereby contributing to a significant increase in 1000-grain weight (12.4 and 9.0% in 2010 and 2011, respectively). The TS-ANT phase was the only phase prior to anthesis exhibiting an extension from old to modern cultivars; this phase increased 1.56 °Cd syear−1. Spike fertility index (SFI) showed increases of 37.8 and 23.8% in 2010 and 2011, respectively. Shortening of the time to flowering, shifting of critical phases of wheat development to better environmental conditions (i.e., TS-ANT phase), and selection for shorter cultivars have been directly responsible for the increase in spike dry weight at anthesis (SDWa) and SFI [i.e., grain number (GN)].

Drought stress on reproductive stages constitute a major problem for common bean (Phaseolus vulgaris L.) production because it affects flowering and pod-filling processes which are highly drought-sensitive. In this study, we used a greenhouse experiment to evaluate the response to drought stress in ten highly cultivated Brazilian genotypes in response to moderate intermittent drought during flowering and pod-filling periods (R7 and R8 stages). Morphological, biochemical, physiological and agronomic traits were used to identify tolerant cultivars and elucidate their strategies to cope this stress. The drought intensity index for the experiment reached 0.63. The cultivar IAC Imperador can be defined as a tolerant cultivar, presenting the lowest grain yield reduction (43%) and a reduced drought susceptibility index (0.65). This cultivar elevated their level of proline in roots under stress, which allowed the osmotic adjustment and the maintenance of an intermediate stomata closure during the day, which maintained the intrinsic WUE stable in NS and DS conditions. In addition, this cultivar was able to mobilize the assimilated carbon for the production of pods and grains, evidenced by the high harvest index and the high grain filling index. In this way, IAC Imperador can be used as a check in breeding programs to identify and select lineages with drought tolerance in common bean.

O objetivo deste trabalho foi avaliar o efeito de doses do regulador de crescimento trinexapac-ethyl e níveis de adubação nitrogenada sobre o desempenho agronômico e rendimento de grãos de três cultivares de trigo. O delineamento experimental foi de blocos ao acaso, em esquema fatorial, com três repetições, sendo: duas doses de adubação nitrogenada (60 e 120 kg ha-1), três cultivares de trigo (BRS 208, BRS 220 e BRS Guamirim), quatro doses de trinexapac-ethyl (0, 70, 140 e 210 g i.a. ha-1) e duas safras agrícolas (2008 e 2009). Na microrregião de Pato Branco, a dose de 60 kg ha-1 é suficiente para maximizar o potencial de rendimento de grãos dos cultivares avaliados. Independentemente da estatura dos cultivares, o regulador de crescimento não apresentou efeito positivo sobre o rendimento de grãos, com efeito negativo na presença de menor disponibilidade hídrica. The objective of this work was to evaluate the effect of trinexapac-ethyl and nitrogen doses on the agronomic performance and grain yield of three wheat cultivars. The experiment was arranged in a randomized block design in a factorial scheme, with three replications. The treatments were two nitrogen fertilization doses (60 and 20 kg ha-1), three wheat cultivars (BRS 208, BRS 220, and BRS Guamirim), four trinexapac-ethyl doses (0, 70, 140, and 210 g a.i. ha-1) and two harvest years (2008 and 2009). In the Pato Branco microregion, the nitrogen rate of 60 kg ha-1 was sufficient to maximize the yield potential of the evaluated cultivars. Regardless of the height of the cultivar plants, trinexapac-ethyl showed no positive effect on grain yield, with negative effect under water-deficit stress.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:26:15Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:36:29Z : No. of bitstreams: 1 2-s2.0-84860715853.pdf: 104673 bytes, checksum: 83517ecf4d3b7957622030cbda8fa85e (MD5) Made available in DSpace on 2014-05-27T11:26:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-01 The metabolic effects caused by hydric deficiency (HD) on Eucalyptus grandis clones were assessed by an experiment where plants were cultivated in four blocks. The first was the control block, normally irrigated, whereas the other three blocks were submitted to cycles of hydric deficiency. Analysis of photosynthetic efficiency, enzymatic activity of antioxidant response system, level of pigments and L-proline concentration were performed to evaluate the HD effects. Results showed that HD altered some parameters related to photosynthetic activity, pigments accumulation, proline and enzymatic activity. Clone 433 of E. grandis presented higher response ability to HD. Department of Chemistry and Biochemistry Institute of Biosciences São Paulo State University (Unesp), 18618-000, Botucatu, São Paulo Laboratory of Plant Physiology and Biochemistry Department of Agronomy Federal Technological University of Paraná (UTFPR), 85503-390, Pato Branco, Paraná Departamento de Riego Centro de Edafología y Biología Aplicada del Segura (CSIC), P.O. Box 164, E-30100 Murcia Department of Chemistry and Biochemistry Institute of Biosciences São Paulo State University (Unesp), 18618-000, Botucatu, São Paulo

O trabalho teve por objetivo avaliar o efeito alelopático de extratos aquosos de cinco cultivares de aveia branca (Avena sativa L.) e quatro de aveia preta (Avena strigosa Schreb), nas concentrações de 0, 25%, 50% e 100%, sobre a germinação e o desenvolvimento das plântulas de azevém (Lolium multiflorum Lam.) e amendoim-bravo (Euphorbia heterophylla L.). O delineamento utilizado foi o inteiramente casualizado distribuído em um trifatorial (genótipos de aveia x plantas infestantes x concentrações do extrato). Utilizaram-se placas de Petri contendo 25 sementes de plantas infestantes que foram umedecidas com extrato da parte aérea dos genótipos de aveia. As variáveis observadas foram: percentual de germinação, comprimento de radícula e de hipocótilo, avaliados aos 14 dias após a instalação do experimento. Os extratos aquosos das cultivares de aveia branca e preta inibiram o potencial alelopático sobre a germinação e o desenvolvimento das plantas daninhas testadas, e os genótipos de aveia branca 'IPR 126', 'UTF Iguaçu' e 'Fundacep FAPA 43' e de aveia preta 'UPFA 21 Moreninha' e 'UTG 9715' foram mais efetivos na inibição da germinação e no desenvolvimento do azevém e amendoim-bravo.The objective of this study was to evaluate the allelopathic effect of aqueous extracts from five common oat (Avena sativa L.) and four black oat (Avena strigosa Schreb) cultivars, at concentrations of 0, 25, 50, and 100%, on the germination and development of ryegrass (Lolium multiflorum Lam.) and wild poinsettia (Euphorbia heterophylla L.) plantlets. A completely randomized design was adopted, distributed as a triple factorial arrangement (oat genotypes × weeds × concentrations). The experiment consisted of Petri dishes containing 25 weed seeds moistened with extract from the above-ground part of the oat genotypes. The following variables were observed: germination percentage, radicle length, and hypocotyl length, evaluated at 14 days after the experiment was installed. The aqueous extracts from common oat and black oat cultivars showed allelopathic potential on the germination and development of the weeds tested. Common oat genotypes 'IPR 126', 'UTF Iguaçu', and 'Fundacep FAPA 43', and black oat genotypes 'UPFA 21 Moreninha' and 'UTG 9715' were the most effective to inhibit ryegrass and wild poinsettia germination and development.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:51Z No. of bitstreams: 1 S0001-37652009000400008.pdf: 1488595 bytes, checksum: 66dbd30172ab185c5dda78aeb700cc1e (MD5) Made available in DSpace on 2013-08-22T18:49:51Z (GMT). No. of bitstreams: 1 S0001-37652009000400008.pdf: 1488595 bytes, checksum: 66dbd30172ab185c5dda78aeb700cc1e (MD5) Previous issue date: 2009-12-01 Made available in DSpace on 2013-09-30T19:40:16Z (GMT). No. of bitstreams: 2 S0001-37652009000400008.pdf: 1488595 bytes, checksum: 66dbd30172ab185c5dda78aeb700cc1e (MD5) S0001-37652009000400008.pdf.txt: 27663 bytes, checksum: 7fe48c39500f41255e070b3f187e808e (MD5) Previous issue date: 2009-12-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:10:41Z No. of bitstreams: 2 S0001-37652009000400008.pdf: 1488595 bytes, checksum: 66dbd30172ab185c5dda78aeb700cc1e (MD5) S0001-37652009000400008.pdf.txt: 27663 bytes, checksum: 7fe48c39500f41255e070b3f187e808e (MD5) Made available in DSpace on 2014-05-20T15:10:41Z (GMT). No. of bitstreams: 2 S0001-37652009000400008.pdf: 1488595 bytes, checksum: 66dbd30172ab185c5dda78aeb700cc1e (MD5) S0001-37652009000400008.pdf.txt: 27663 bytes, checksum: 7fe48c39500f41255e070b3f187e808e (MD5) Previous issue date: 2009-12-01 O objetivo deste trabalho foi resgatar e documentar o conhecimento popular referente às plantas medicinais utilizadas na comunidade rural do Passo da Ilha, em Pato Branco-PR (26° 11' S, 52°36' W e 760 m de altitude). Optou-se por utilizar o modelo de entrevista estruturada com 16 informantes, os quais possuíam o conhecimento sobre o uso das plantas medicinais em suas famílias. O período da realização das entrevistas foi de outubro a dezembro de 2000. As plantas foram coletadas no campo, identificadas e vouchers foram depositados no Herbário Irina Delanova de Gemtchjnicov (BOTU) da Universidade Estadual Paulista, em Botucatu-SP. Foram identificadas 47 famílias botânicas e 114 espécies de plantas medicinais. Estas plantas foram indicadas para mais de 30 usos medicinais diferentes. A comunidade é composta na maioria por descendentes de europeus, justificando a presença de muitas plantas exóticas. O domínio do uso das plantas é feminino, porém o conhecimento é menor nas gerações mais novas, denotando um processo de erosão cultural. The scope of this work was to rescue and document the traditional knowledge regarding the medicinal plants used by Passo da Ilha rural community, in Pato Branco, Paraná State, Southern Brazil (26° 11' S, 52°36' W and 760 m high). Structured interviews were made in field research with 16 informants who had the traditional knowledge about medicinal plants. The research was carried out from October to December 2000. The plants were collected in the field, identified and their vouchers were housed at the Herbarium Irina Delanova de Gemtchjnicov (BOTU) of São Paulo State University, in Botucatu. A total of 47 botanical families and 114 species of medicinal plants were identified. These plants ere suitable for ore than 30 different edicinal uses. The residents are mainly of European descent, which justify the presence of many exotic plants. The knowledge on how to use medicinal plants properly is held mainly by the females, and decreases in the newer generations, denoting cultural erosion in progress. Universidade Tecnológica Federal do Paraná Universidade Estadual Paulista Faculdade de Ciências Agrárias Secretaria de Educação Universidade Estadual Paulista Faculdade de Ciências Agrárias

O objetivo do presente trabalho foi caracterizar o efeito alelopático do extrato aquoso de folhas de A. annua sobre a germinação de sementes e o desenvolvimento de plântulas de alface (Lactuca sativa L.) e leiteiro (Euphorbia heterophylla L.). O extrato aquoso bruto foi preparado a partir de 250 g folhas frescas extraídas em 1 L de água destilada. Este primeiro extrato foi filtrado e centrifugado, sendo utilizado o sobrenadante. Foram utilizadas as seguintes concentrações de 100% (extrato filtrado e centrifugado); 75%, 50% e 25% (diluições do extrato 100%); e 0% (água destilada). As sementes das espécies testadas foram distribuídas em placas de petri e acondicionadas em câmara de germinação. Foram analisadas as variáveis: germinabilidade (G), velocidade média de germinação (V), tempo médio de germinação (t), comprimento da radícula (CR) e massa seca das plântulas. A elevação da concentração do extrato aquoso de A. annua provocou redução na germinabilidade de alface e, a partir da concentração de 50%, a germinação foi completamente inibida. Para o leiteiro, a germinação foi totalmente inibida a partir da concentração de 75%. Observou-se também redução significativa na velocidade média de germinação de alface com a elevação da concentração do extrato, efeito que não foi observado para o leiteiro. O comprimento radicular do leiteiro foi significativamente reduzido nas concentrações de 25 e 50%, e totalmente inibido em 75 e 100%. Para alface, a concentração de 25% reduziu significativamente o comprimento radicular, e as concentrações de 50, 75 e 100% inibiram completamente a formação de raízes, mostrando ser esta espécie mais sensível que o leiteiro. Extratos aquosos de A. annua apresentaram ação alelopática inibitória sobre a germinação de sementes e o desenvolvimento de plântulas de alface e leiteiro. The aim of this work was to study the allelopathic effect of leaf aqueous extract of A. annua on seed germination and seedling development in lettuce (Lactuca sativa L.) and wild poinsettia (Euphorbia heterophylla L.). Crude aqueous extract was prepared from 250 g fresh leaves extracted in 1 L distilled water. This first extract was filtered and centrifuged and the supernatant was used. The following concentrations were employed of 100% (filtered and centrifuged extract), 75%, 50%, 25% (dilutions of the 100% extract) and 0% (distilled water). Seeds of the tested species were distributed in Petri dishes and placed into germination chambers. The analyzed variables were: germinability (G), germination mean velocity (V), germination mean time (t), radicle length (RL) and seedling dry matter. The increase in the concentration of A. annua aqueous extract reduced lettuce germinability and, from 50% concentration, germination was completely inhibited. For wild poinsettia, germination was completely inhibited from 75% concentration. There was a significant reduction in lettuce germination mean velocity with increasing extract concentrations, which was not observed for wild poinsettia. Radicle length in wild poinsettia significantly reduced at the concentrations 25 and 50% and was totally inhibited at 75 and 100%. As regards lettuce, 25% concentration significantly reduced radicle length, and the concentrations 50, 75 and 100% completely inhibited root formation, indicating this species is more sensitive than wild poinsettia. A. annua aqueous extracts presented inhibitory allelopathic action on seed germination and seedling development in lettuce and wild poinsettia.

O uso das técnicas de fertirrigação em ambiente protegido vem aumentando no Brasil devido à praticidade de condução e redução dos custos de produção. Apesar dessas vantagens, salienta-se que esta prática também pode trazer riscos, principalmente pelo acúmulo de sais na superfície do solo e na região periférica do bulbo radicular. Em caso de salinização do solo pelo manejo incorreto do sistema podem ocorrer alterações na disponibilidade de nutrientes, com conseqüências fisiológicas no desenvolvimento das plantas. Neste trabalho, utilizou-se o pimentão (Capsicum annuum L.) como planta-modelo para estudos da interferência da salinidade na nutrição das plantas, pela alteração da condutividade elétrica (CE) na solução do solo. Os resultados revelaram indícios de antagonismo entre nutrientes, notadamente entre as formas catiônicas em razão do aumento da concentração de KCl nos tratamentos com alta CE. A suplementação do solo com adubo orgânico não atenuou os efeitos do aumento da concentração salina e os valores extremos de CE interferiram drasticamente na produção.The use of fertigation techniques in greenhouse is increasing in Brazil due to the facilities and reduction of the costs of production. In spite of these advantages, it is pointed out that this practice can also bring risks, mainly for the accumulation of salts in the surface of the soil and in the peripheric root site of the bulb. In case of soil salinization due to incorrect handling of the system, it can happen alterations in the disponibility of nutrients, with physiological consequences to the development of the plants. In this research, the bell pepper (Capsicum annuum L.) was used as model for studies of the interference of the salinity in plant nutrition and yield. The obtained results revealed some antagonism among nutrients, especially among the cationic forms due to the increase of the KCl concentration in the treatments with high EC. The supplying of the soil with organic matter did not attenuate the effects of the increase of the saline concentration and the extreme values of EC interfered drastically in the production.

The use of different genetic dissimilarity indicators can help in both the selection of crop improvement strategies and as artificial crosses. The objectives of this work were to estimate the genetic dissimilarity among seven oat genotypes (Avena sativa L.) through molecular (dg) and morphological (dm) markers. Data were obtained from two experiments carried out in Capão do Leão County, RS, Brazil, in 2000. The estimated correlation coefficient (r = 0.33) indicated a low association between dg and dm estimates. The genotypes with similar pedigrees (UPF 16 and UPF 17), with a bootstrapping value of 82.7%, performed the most consistent group (dg) and clustered more closely in both techniques (dg and dm). However, genotypes with similar pedigree clustered in distant groups. Both dissimilarity estimates need to be used in order to obtain a more reliable choice of dissimilar parents, with higher probability of developing promising base populations.O uso de diferentes medidas de dissimilaridade genética auxilia na definição de estratégias de melhoramento e no direcionamento de cruzamentos artificiais. O objetivo deste trabalho foi estimar a dissimilaridade genética entre sete genótipos de aveia branca (Avena sativa L.) através de marcadores moleculares AFLP (dg) e caracteres agronômicos (dm). Os resultados foram constatados em dois experimentos desenvolvidos no município de Capão do Leão (RS), Brasil, em 2000. O coeficiente de correlação encontrado (r=0.33) indicou baixa correspondência entre as estimativas de dg e dm. Os genótipos com a mesma genealogia (UPF 16 e UPF 17), com valor de bootstraping de 82,7%, formaram o grupo mais consistente (dg) e o agrupamento mais similar em ambas as técnicas (dg e dm); entretanto, agruparam-se genótipos de genealogia similar em diferentes grupos. Ambas as estimativas de dissimilaridade, quando utilizadas conjuntamente, proporcionam maior suporte para a escolha de genitores dissimilares, com grande probabilidade de desenvolvimento de populações-base promissoras.

The use of different genetic dissimilarity indicators can help in both the selection of crop improvement strategies and as artificial crosses. The objectives of this work were to estimate the genetic dissimilarity among seven oat genotypes (Avena sativa L.) through molecular (dg) and morphological (dm) markers. Data were obtained from two experiments carried out in Capão do Leão County, RS, Brazil, in 2000. The estimated correlation coefficient (r = 0.33) indicated a low association between dg and dm estimates. The genotypes with similar pedigrees (UPF 16 and UPF 17), with a bootstrapping value of 82.7%, performed the most consistent group (dg) and clustered more closely in both techniques (dg and dm). However, genotypes with similar pedigree clustered in distant groups. Both dissimilarity estimates need to be used in order to obtain a more reliable choice of dissimilar parents, with higher probability of developing promising base populations. O uso de diferentes medidas de dissimilaridade genética auxilia na definição de estratégias de melhoramento e no direcionamento de cruzamentos artificiais. O objetivo deste trabalho foi estimar a dissimilaridade genética entre sete genótipos de aveia branca (Avena sativa L.) através de marcadores moleculares AFLP (dg) e caracteres agronômicos (dm). Os resultados foram constatados em dois experimentos desenvolvidos no município de Capão do Leão (RS), Brasil, em 2000. O coeficiente de correlação encontrado (r=0.33) indicou baixa correspondência entre as estimativas de dg e dm. Os genótipos com a mesma genealogia (UPF 16 e UPF 17), com valor de bootstraping de 82,7%, formaram o grupo mais consistente (dg) e o agrupamento mais similar em ambas as técnicas (dg e dm); entretanto, agruparam-se genótipos de genealogia similar em diferentes grupos. Ambas as estimativas de dissimilaridade, quando utilizadas conjuntamente, proporcionam maior suporte para a escolha de genitores dissimilares, com grande probabilidade de desenvolvimento de populações-base promissoras.

The use of high nitrogen doses, associated with the application of growth reducers, can be an alternative to wheat plants express high productive potential without the occurrence of lodging. For this reason, the aim of this study was to evaluate the effect of trinexapac-ethyl growth reducer associated with high and split nitrogen fertilization on yield and its components in wheat cultivar BRS 220. The experimental design was randomized blocks with two treatment and four replications, compose with the application of 110 kg N ha-1 with or without 0,4 g L-1 of trinexapac-ethyl. It was evaluated yield and its components, stem diameter, length of internode, plant height and stem length and the averages were submitted to Student t-test using Systat 13®. The application of the growth retardant contributed to a significant increase in yield and stem diameter of the plants, besides the reduction of height and length of stem and internode, when compared to the treatment without product application.

Federal University for Technology of Parana Laboratory of Biochemistry and Plant Physiology, Pato Branco 85503-390

Isotope screening is a simple test for determining the photosynthetic pathway used by plants. The scope of this work was to classify the photosynthetic type of some herbs and medicinal plants through studies of the carbon isotope composition (δ13C). Also, we propose the use of carbon isotope composition as a tool to control the quality of herbs and medicinal plants. For studies of δ13C, δ13C‰ = [R (sample)/R (standard) − 1] × 10−3, dry leaves powdered in cryogenic mill were analyzed in a mass spectrometer coupled with an elemental analyzer for determining the ratio R = 13CO2/12CO2. In investigation of δ13C of 55 species, 23 botanical families, and 44 species possessed a C3 photosynthetic type. Six species found among the botanical families Euphorbiaceae and Poaceae were C4 plants, and 5 species found among the botanical families Agavaceae, Euphorbiaceae, and Liliaceae possessed CAM-type photosynthesis. Carbon isotope composition of plants can be used as quality control of herbs and medicinal plants, allowing the identification of frauds or contaminations. Also, the information about the photosynthetic type found for these plants can help in introducing and cultivating exotic and wild herbs and medicinal plants.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:15Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:39:53Z : No. of bitstreams: 1 2-s2.0-18444399306.pdf: 117433 bytes, checksum: 65b6e2183e9543e563858c0210a43cf5 (MD5) Made available in DSpace on 2014-05-27T11:21:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-01-01 Leaves of Artemisia annua L. are a plentiful source of artemisinin, a drug with proven effectiveness against malaria. The aim of this study was to classify the photosynthetic mechanism of A. annua through studies of the carbon isotope composition (δ 13C) and the leaf anatomy. A. annua presented a δ 13C value of - 31.76 ± 0.07, which characterizes the plants as a typical species of the C3 photosynthethic mechanism, considering that the average δ 13C values for C3 and C4 species are -28 and -14, respectively. The leaf anatomy studies were consistent with the δ 13C results, where, in spite of the existence of parenchymatic cells forming a sheath surrounding the vascular tissue, the cells do not contain chloroplasts or starch. This characteristic is clearly different from that of the Kranz anatomy found in C4 species. Laboratory of Biochemistry and Plant Physiology Agronomy College CEFET-PR, Pato Branco 85503-390 Institute of Biosciences São Paulo State University, Botucatu 18618-000 Agronomic Sciences College São Paulo State University, Botucatu 18603-970 Plant Biology Department Viçosa Federal University, Viçosa 36570-000 Institute of Biosciences São Paulo State University, Botucatu 18618-000 Agronomic Sciences College São Paulo State University, Botucatu 18603-970

Diagnosticou-se o perfil dos consumidores de supermercados em Pato Branco (PR), com relação às suas preferências pelas plantas medicinais e condimentares, como subsídio à produção por pequenos produtores rurais. Os consumidores preferem produtos orgânicos, observam a aparência e o preço do produto, e vão ao mercado uma vez por semana, preferencialmente aos sábados. As dez plantas medicinais preferidas, em ordem decrescente, são camomila, anis, boldo, carqueja, guaco, malva, poejo, espinheira-santa, menta e sálvia. As dez plantas condimentares preferidas, em ordem decrescente, são cebola, cravo, canela, orégano, alho, nóz-moscada, pimentão, cebolinha, endro e salsinha.The profile of supermarket users in Pato Branco city, Paraná State, Brazil, was obtained, related to their preference for medicinal and spice plants, as a subsidy to production by small farmers. The consumers prefer organic products observing the appearance and price of the product, and they go once a week to the market, preferably on Saturdays. The ten favorite medicinal plants are Chamomilla recutita, Pimpinella anisum, Vernonia condensata, Baccharis sp., Mikania sp., Malva sp., Cunilla sp., Maytenus sp., Mentha sp. and Salvia officinalis. The ten favorite spices are: Allium cepa, Eugenia caryophyllata, Cinnamomum zeylanicum, Origanum vulgaris, Allium sativum, Myristicia fragans, Capsicum annuum, Allium schoenoprasum, Anethum graveolens and Petroselinum crispum.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:55:07Z No. of bitstreams: 1 S0102-05362004000200034.pdf: 375974 bytes, checksum: 022a39b88e88f3b4107360119c106462 (MD5) Made available in DSpace on 2013-08-22T18:55:07Z (GMT). No. of bitstreams: 1 S0102-05362004000200034.pdf: 375974 bytes, checksum: 022a39b88e88f3b4107360119c106462 (MD5) Previous issue date: 2004-06-01 Made available in DSpace on 2013-09-30T19:47:38Z (GMT). No. of bitstreams: 2 S0102-05362004000200034.pdf: 375974 bytes, checksum: 022a39b88e88f3b4107360119c106462 (MD5) S0102-05362004000200034.pdf.txt: 16576 bytes, checksum: cf796672703e45da5caacd43e1e20eb2 (MD5) Previous issue date: 2004-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:19:36Z No. of bitstreams: 2 S0102-05362004000200034.pdf: 375974 bytes, checksum: 022a39b88e88f3b4107360119c106462 (MD5) S0102-05362004000200034.pdf.txt: 16576 bytes, checksum: cf796672703e45da5caacd43e1e20eb2 (MD5) Made available in DSpace on 2014-05-20T13:19:36Z (GMT). No. of bitstreams: 2 S0102-05362004000200034.pdf: 375974 bytes, checksum: 022a39b88e88f3b4107360119c106462 (MD5) S0102-05362004000200034.pdf.txt: 16576 bytes, checksum: cf796672703e45da5caacd43e1e20eb2 (MD5) Previous issue date: 2004-06-01 Diagnosticou-se o perfil dos consumidores de supermercados em Pato Branco (PR), com relação às suas preferências pelas plantas medicinais e condimentares, como subsídio à produção por pequenos produtores rurais. Os consumidores preferem produtos orgânicos, observam a aparência e o preço do produto, e vão ao mercado uma vez por semana, preferencialmente aos sábados. As dez plantas medicinais preferidas, em ordem decrescente, são camomila, anis, boldo, carqueja, guaco, malva, poejo, espinheira-santa, menta e sálvia. As dez plantas condimentares preferidas, em ordem decrescente, são cebola, cravo, canela, orégano, alho, nóz-moscada, pimentão, cebolinha, endro e salsinha. The profile of supermarket users in Pato Branco city, Paraná State, Brazil, was obtained, related to their preference for medicinal and spice plants, as a subsidy to production by small farmers. The consumers prefer organic products observing the appearance and price of the product, and they go once a week to the market, preferably on Saturdays. The ten favorite medicinal plants are Chamomilla recutita, Pimpinella anisum, Vernonia condensata, Baccharis sp., Mikania sp., Malva sp., Cunilla sp., Maytenus sp., Mentha sp. and Salvia officinalis. The ten favorite spices are: Allium cepa, Eugenia caryophyllata, Cinnamomum zeylanicum, Origanum vulgaris, Allium sativum, Myristicia fragans, Capsicum annuum, Allium schoenoprasum, Anethum graveolens and Petroselinum crispum. Centro Federal de Educação Tecnológica Laboratório de Bioquímica e Fisiologia Vegetal Universidade Estadual Paulista Departamento de Química e Bioquímica Universidade Estadual Paulista Departamento de Produção Vegetal Universidade Estadual Paulista Departamento de Química e Bioquímica Universidade Estadual Paulista Departamento de Produção Vegetal

Made available in DSpace on 2016-04-01T18:45:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2014. Added 1 bitstream(s) on 2016-04-01T18:50:57Z : No. of bitstreams: 1 ISSN0718-3429-2014-32-01-09-16.pdf: 184429 bytes, checksum: 7d6aa5711ebedeb75a576aec66f312b6 (MD5) La producción en invernadero asociada al manejo de fertirriego se ha establecido en Brasil como una alternativa económica para varias especies hortícolas. Este estudio tuvo como objetivo evaluar posibles impactos en el metabolismo en plantas de pimiento (Capsicum annuum L.; cv Elisa). En respuesta al aumento de la concentración mineral del suelo debido al fertirriego durante los ensayos, fueron alteradas las concentraciones de nutrientes para inducir altos valores de conductividad eléctrica (CE) en la solución del suelo. Valores de CE observados comúnmente en sistemas de fertirriego convencionales fueron tomados como tratamiento control. Se estudió también la posibilidad de la reducción del impacto del estrés mineral mediante la aplicación de materia orgánica en el sustrato del cultivo. Parámetros del sistema de respuesta antioxidativo, como la actividad de las enzimas superóxido dismutasa (SOD), catalasa además de prolina fueron evaluadas para medir el alcance de los efectos del estrés salino y sus efectos metabólicos. El aumento de la CE en la solución del suelo indujo fuertemente la concentración de prolina y la actividad de la enzima SOD. Se observó que el estrés salino causó inhibición de la actividad de las catalasas. En función de los resultados obtenidos, se concluye que el monitoreo de la CE de la solución del suelo es un factor indispensable para tener éxito en las prácticas de la fertirrigación y que el estudio de la actividad enzimática del sistema de respuesta antioxidativo y contenido de prolina pueden asumir un papel importante como indicadores de los niveles de estrés en plantas de pimiento (Capsicum annuum L.; cv Elisa). The greenhouse production associated with the fertigation management, have established in Brazil as economical alternative for several horticultural species. With this strategy this study had as aim to evaluate possible impacts in the metabolism of plants of bell pepper (Capsicum annuum L.; cv Elisa) in response to the increase of mineral concentration in the soil. During the experiments, the some nutrient concentrations were altered, to obtain high values of electric conductivity (EC) in the soil solution. The EC values commonly observed in the traditional fertigation system were adopted, as control. It was also verified the possibility of reduction of the mineral stress impact by the application of organic matter in the soil. Parameters of the antioxidative response system, as the superoxide dismutase (SOD) and catalase enzyme activities besides the proline content were evaluated to measure the extension of the saline stress and their effects on the plants. The increase of EC of the soil induced to the increase of the proline concentration and the SOD activity. Unexpectedly, it was verified that the saline stress inhibited the activity of the enzyme catalase. It was also concluded that the monitoring of EC of the soil is an indispensable tool to reach success in the fertigation system and that the study of the activity of the enzymes of the antioxidative response system, and the proline contents can be assumed as indicators in of the levels of stress in bell pepper plants (Capsicum annuum L.; cv Elisa). Universidade Tecnológica Federal do Paraná, Laboratório de Bioquímica e Fertilidade do Solo, Faculdade de Agronomia Centro de Investigación en Química Aplicada, Departamiento de Agroplasticultura, Universidade Estadual Paulista, Departamento de Engenharia Rural, Faculdade de Ciências Agronômicas de Botucatu Universidade Estadual Paulista, Departamento de Química e Bioquímica, Instituto de Biociências de Botucatu

The effect of different doses of nitrogen (N) on gas exchange, relative chlorophyll (Chl) amount, and the content of N in the aerial biomass of lisianthus was evaluated. The treatments consisted of six different concentrations of N (50, 100, 150, 200, 250, and 300 g m−3 noted as N50, N100, N150, N200, N250, and N300, respectively), applied through the fertirrigation technique. N250 and N300 induced increase in the contents of foliar Chl and N in the aerial biomass, that in turn contributed to an increase of photosynthetic activity in lisianthus.

espanolEl potasio asi como el nitrogeno constituyen los elementos necesarios para el crecimiento, desarrollo y produccion del cultivo del algodon. Ademas, estos elementos estan directamente relacionados con la formacion de las fibras y cuando se proporcionan en forma adecuada, garantizan la calidad de las mismas. Con el objetivo de evaluar la influencia del potasio sobre parametros biometricos, produccion y calidad de la fibra del algodon, fueron cultivadas en invernadero plantas del cultivar Delpa opal, con fertilizacion potasica alterada, simulando deficiencia (subdosis) y dos niveles de sobredosis. Durante las diferentes fases fenolo- gicas del cultivo fueron analizadas variables biometricas incluyendo la produccion de fibras y sus parametros cualitativos. Los tratamientos de subdosis de potasio y las sobredosis aplicadas alteraron todos los parametros evaluados, demostrando la importancia de la fertilizacion potasica sobre los mismos. EnglishPotassium, like nitrogen, it constitutes an essential element for growth, development and production of cotton crops. Moreover, these elements are directly related to fiber formation and when provided in suitable doses, influences its quality. The aim of the experiments was to evaluate the influence of potassium on biometric parameters, yield and quality of cotton fibers. For this purpose, plants of the cultivar Delta opal were grown in a greenhouse with altered potassium fertilization, simulating K deficiency and two overdoses. During the different phenological stages, biometric variables were analyzed including the production of fibers and their qualitative parameters. The sub-dose and the overdoses treatments of K, changed all the evaluated parameters, demonstrating the importance of potassium fertilizer on them.

O objetivo deste trabalho foi avaliar o efeito dos eliciadores acibenzolar‑S‑metílico (ASM) e proteína harpina, aplicados em pós‑colheita, na indução de resistência sistêmica à podridão‑amarga em maçãs. Realizaram-se ferimentos mecânicos em maçãs 'Royal Gala' seguidos da aplicação dos eliciadores. Doze horas depois, procedeu-se à inoculação do fungo Colletotrichum gloeosporioides. Após 72 horas, realizaram-se as avaliações quanto à área lesionada e ao número de esporos, bem como a coleta de tecido dos frutos para quantificação de proteínas, açúcares totais e redutores, fenóis totais, e para determinação da atividade das enzimas fenilalanina amônia‑liase, superóxido dismutase, catalase, peroxidase e ascorbato peroxidase. A harpina e, em menor grau, o ASM proporcionaram aumento da atividade da enzima peroxidase e a consequente redução da área lesionada e da esporulação de C. gloeosporioides nas maçãs. Esses eliciadores podem ser utilizados como ferramenta de controle no manejo integrado da podridão‑amarga, em pós‑colheita de maçãs 'Royal Gala'.

O objetivo do estudo foi avaliar por meio da análise de crescimento, as variações nas características fisiológicas do feijoeiro comum, cultivar IPR Tiziu, submetidos a diferentes densidades de semeadura, buscando identificar a melhor disposição espacial das plantas. O delineamento experimental foi de blocos ao acaso com quatro repetições, os tratamentos consistiram de cinco densidades de semeadura (DS): 8, 10, 12, 14 e 18 plantas m-1, respectivamente, 20, 25, 30, 35, 40 pl m-2. Para avaliação, semanalmente coletaram-se 12 plantas de cada parcela. Os resultados evidenciaram aumento do índice de área foliar (IAF) e da matéria seca total (MST) até 57 dias após a emergência (DAE), enquanto a taxa de crescimento da cultura (TCC), taxa de crescimento relativo (TCR), taxa assimilatória líquida (TAL) e razão de área foliar (RAF) apresentaram redução durante o ciclo da cultura. A DS de 30 pl m-2 foi a mais eficiente no aproveitamento dos recursos do ambiente quanto à conversão de energia luminosa e CO2 em MST, já que apresentou os maiores valores de MST, TCC e TAL. Entretanto, os tratamentos não diferiram significativamente entre si para os componentes do rendimento e rendimento de grãos. A maior DS promoveu menor TAL, TCC, RAF devido ao aumento do IAF, o que provocou auto-sombreamento na cultura, diminuindo a eficiência fotossintética do feijoeiro.

O trabalho teve por objetivo avaliar o efeito alelopático de extratos aquosos de cinco cultivares de aveia branca (Avena sativa L.) e quatro de aveia preta (Avena strigosa Schreb), nas concentrações de 0, 25%, 50% e 100%, sobre a germinação e o desenvolvimento das plântulas de azevém (Lolium multiflorum Lam.) e amendoim-bravo (Euphorbia heterophylla L.). O delineamento utilizado foi o inteiramente casualizado distribuído em um trifatorial (genótipos de aveia x plantas infestantes x concentrações do extrato). Utilizaram-se placas de Petri contendo 25 sementes de plantas infestantes que foram umedecidas com extrato da parte aérea dos genótipos de aveia. As variáveis observadas foram: percentual de germinação, comprimento de radícula e de hipocótilo, avaliados aos 14 dias após a instalação do experimento. Os extratos aquosos das cultivares de aveia branca e preta inibiram o potencial alelopático sobre a germinação e o desenvolvimento das plantas daninhas testadas, e os genótipos de aveia branca 'IPR 126', 'UTF Iguaçu' e 'Fundacep FAPA 43' e de aveia preta 'UPFA 21 Moreninha' e 'UTG 9715' foram mais efetivos na inibição da germinação e no desenvolvimento do azevém e amendoim-bravo. The objective of this study was to evaluate the allelopathic effect of aqueous extracts from five common oat (Avena sativa L.) and four black oat (Avena strigosa Schreb) cultivars, at concentrations of 0, 25, 50, and 100%, on the germination and development of ryegrass (Lolium multiflorum Lam.) and wild poinsettia (Euphorbia heterophylla L.) plantlets. A completely randomized design was adopted, distributed as a triple factorial arrangement (oat genotypes × weeds × concentrations). The experiment consisted of Petri dishes containing 25 weed seeds moistened with extract from the above-ground part of the oat genotypes. The following variables were observed: germination percentage, radicle length, and hypocotyl length, evaluated at 14 days after the experiment was installed. The aqueous extracts from common oat and black oat cultivars showed allelopathic potential on the germination and development of the weeds tested. Common oat genotypes 'IPR 126', 'UTF Iguaçu', and 'Fundacep FAPA 43', and black oat genotypes 'UPFA 21 Moreninha' and 'UTG 9715' were the most effective to inhibit ryegrass and wild poinsettia germination and development.

Despite the importance of Artemisia annua L. as the only source of the anti-parasitic drug artemisinin, little is known on the effects of biotic and abiotic stress on artemisinin accumulation. Water deficit is the most limiting factor on plant growth, however it can trigger secondary metabolite accumulation, depending on the plant growth stage and intensity. A. annua cultivated in growth chambers was submitted to five water deficit treatments (watered, 14, 38, 62 e 86 hours without irrigation). Water deficits of 38 and 62 hours (Yw = -1.39 and -2.51 MPa, respectively) increased leaf artemisinin content, but only 38 hours led to a significant increase in both leaf and plant artemisinin (29%), with no detriment to plant biomass production. The other treatments had no effect on, or decreased artemisinin accumulation. A. annua plants tolerated well water deficit treatments, including the most severe water deficit applied (Yw -3.97 MPa or 86 hs without irrigation) and recovered their turgor pressure after rehydration. These results suggest that moderate water deficit prior to harvesting the crop may not only reduce time and costs in drying the crop, but can also induce artemisinin accumulation, both of which increase crop profit margins. Results also suggest that artemisinin could be part of A. annua chemical system of defense against water deficit. A despeito da importância da Artemisia annua L. como a única fonte da droga anti-parasitária artemisinina, muito pouco é sabido sobre o papel dessa molécula em plantas sob estresses biótico e abiótico. A deficiência hídrica é o principal fator limitante no crescimento vegetal, mas pode induzir a acumulação de metabólitos secundários, dependendo da intensidade e fase de desenvolvimento da planta. Plantas de A. annua cultivadas em câmaras de crescimento foram submetidas a cinco tratamentos (plantas irrigadas e com 14, 38, 62 e 86 horas sem irrigação). Deficiências hídricas de 38 e 62 horas (Yw = -1.39 e -2.51 MPa, respectivamente) aumentaram o conteúdo foliar de artemisinina, mas somente a deficiência hídrica de 38 horas induziu um aumento significativo da molécula em folhas (29%) e planta inteira, sem afetar o acúmulo de biomassa. Os outros tratamentos não afetaram significativamente o conteúdo de artemisinina. As plantas de A. annua apresentaram uma boa tolerância a deficiência hídrica, incluindo o tratamento mais severo (Yw -3.97 MPa ou 86 h sem irrigação) e recuperaram a pressão de turgor após a reidratação. Estes resultados sugerem que uma deficiência hídrica moderada imediatamente antes da colheita de A. annua pode não somente reduzir o tempo e os custos de secagem da cultura, mas também induzir ao acúmulo de artemisinina, condições que, conjuntamente, são benéficas para o cultivo commercial da espécie. Finalmente, estes resultados sugerem que a artemisinina pode ser parte do sistema químico de defesa da A. annua contra a deficiência hídrica.

O trabalho teve por objetivo caracterizar o efeito alelopático do extrato aquoso de acículas de Pinus taeda na germinação e no desenvolvimento inicial de plântulas de aveia preta comum (Avena strigosa). O experimento foi conduzido no Laboratório de Bioquímica e Fisiologia Vegetal da Universidade Tecnológica Federal do Paraná (UTFPR), Campus de Pato Branco, utilizando o delineamento inteiramente casualizado, com tratamento fatorial (bifatorial com parcela subdividida no tempo), com três repetições, sob condições de temperatura, umidade e luminosidade controladas. Os tratamentos foram compostos por cinco concentrações (0, 25, 50, 75 e 100%) de extrato bruto de acículas de pínus em estágio vegetativo (acícula verde), moderadamente decomposto (acícula seca) e em decomposição avançada (acícula decomposta). As avaliações foram realizadas a cada 24 horas. Foram avaliados os parâmetros porcentagem de germinação, velocidade média de germinação e comprimento de radículas e epicótilos das plântulas de Avena strigosa. O estágio de acícula verde afetou significativamente as variáveis avaliadas e esse problema aumentou com a concentração do extrato. The purpose of this study was to verify the allelopathic effect of aqueous extract from the Pinus taeda needles on the germination and development of black oat (Avena strigosa) seedlings. The work was carried out at the Plant Physiology and Biochemistry Laboratory at the Federal Technological University of Paraná (UTFPR), Campus Pato Branco, using a completely randomized design with factorial distribution in three replicates, under temperature, humidity and light controlled conditions. The extract from the pine needles was composed of five percentages (0, 25, 50, 75 and 100%) from the crude extract (EB) dilution, composed of distilled water + pine needles in vegetative stage (green needles), moderately decomposed (dry needles) and in advanced decomposition (decomposed needles). The germination percentage, average speed of germination, the length of the primary roots and the length from the seedlings roots of Avena strigosa were evaluated. The stage of green needles affected the variables studied and showed linearly effect with the increasing concentration of the crude extract.

Na agricultura atual, o método mais utilizado para o controle de plantas daninhas é o químico, em razão da facilidade de uso, elevada eficiência e baixa necessidade de mão de obra. No entanto, a utilização inadequada desses produtos provoca problemas ao ambiente e à saúde humana. Cresce, portanto, a busca por métodos alternativos de controle de plantas daninhas, menos demandadores de energia e menos tóxicos e agressivos ao ambiente. Este trabalho objetivou avaliar o efeito alelopático da cultura do girassol (Helianthus annuus) sobre diferentes espécies de plantas daninhas e cultivadas, em dois experimentos realizados em delineamento experimental completamente casualizado, utilizando o método da semeadura em substituição. O primeiro experimento foi realizado com quatro repetições, em esquema bifatorial. O primeiro fator foi constituído por seis espécies indicadoras: picão-preto (Bidens pilosa), corda-de-viola (Ipomoea grandifolia), caruru (Amaranthus hybridus), alface (Lactuca sativa, cultivar Aurélia), tomate (Lycopersicon esculentum, cultivar Santa Cruz), trigo (Triticum aestivum, cultivar BRS 208); e o segundo, pela presença ou não de plântulas de girassol. O segundo experimento foi composto por 24 tratamentos, representados por 23 genótipos de girassol e por uma testemunha sem girassol, utilizando-se quatro repetições. A espécie indicadora foi apenas o picão-preto. Em ambos os experimentos, no final do período de sete dias de convívio, foram avaliados o número de sementes germinadas e o comprimento radicular e da parte aérea das espécies indicadoras. Não foram observadas diferenças entre as porcentagens de germinação de quaisquer das espécies indicadoras avaliadas, em função da presença ou não das plântulas de girassol. A presença de plântulas de girassol estimulou o crescimento radicular das plântulas de tomate e trigo e inibiu o crescimento da parte aérea de picão-preto, trigo e corda-de-viola. Houve grande variabilidade de potencial alelopático entre genótipos de girassol sobre a germinação e o crescimento radicular e da parte aérea de Bidens pilosa. Os resultados demonstram que a técnica da semeadura em substituição é adequada para detectar efeitos estimulativos ou inibitórios de girassol sobre espécies indicadoras e para discriminar genótipos de girassol quanto à habilidade em inibir ou estimular plântulas de Bidens pilosa. In modern agriculture, the chemical method is the most used for weed control because it is highly efficient, easy to apply, and demands limited labor. However, the inadequate use of chemical products can lead to environmental and human health problems. Thus, there is a growing need to search for alternative weed control methods using substances which are less energy-demanding, less toxic and less aggressive to the environment. This work aimed to evaluate the allelopathic potential of sunflower (Helianthus annuus) culture on different weed and cultivated species, in two experiments conducted in a completely randomized design, using the relay seeding technique. The first experiment was carried out with four repetitions, in a bi-factorial scheme. The first factor was constituted by six indicative target species: beggarticks (Bidens spp.), common morninglory (Ipomoea grandifolia), pigweed (Amaranthus hybridus), lettuce (Lactuca sativa, cv. Aurélia), tomato (Solanum lycopersicum, cv. Santa Cruz), and wheat (Triticum aestivum, cv. BRS 208).The second factor was constituted by the presence or absence of sunflower seedlings. The relay seeding technique was applied. The second experiment was composed by 24 treatments including 23 sunflower genotypes and a control without sunflower, with four repetitions. The indicative species was only the beggarticks. In both experiments, at the end of seven coexistence days, number of germinated seeds, and root and aerial part length of the target species were evaluated. No difference was observed among the germination percentages of the indicative species evaluated in the presence or absence of the sunflower plants. The presence of the sunflower plants stimulated tomato and wheat root growth and inhibited the growth of the beggartick, wheat and common morninglory aerial parts. There was great variability of the potential allelopathic effect of the sunflower genotypes on germination and root and aerial part length of Bidens pilosa. The results show that the relay seeding technique is adapted to discriminate stimulating and inhibiting effects of sunflower among indicative species and to discriminate sunflower genotypes in their ability to inhibit or stimulate Bidens pilosa plants.

We evaluated the growth and development of the medicinal species Pothomorphe umbellata (L.) Miq. under different shade levels (full sun and 30, 50, and 70 % shade, marked as I100, I70, I50, and I30, respectively) and their effects on gas exchange and activities of antioxidant enzymes. Photosynthetically active radiation varied from 1 254 µmol m−2 s−1 at I100 to 285 µmol m−2 s−1 at I30. Stomatal conductance, net photosynthetic rate, and relative chlorophyll (Chl) content were maximal in I70 plants. Plants grown under I100 produced leaves with lower Chl content and signs of chlorosis and necrosis. These symptoms indicated Chl degradation induced by the generation of reactive oxygen species. Stress related antioxidant enzyme activities (Mn-SOD, Fe-SOD, and Cu/Zn-SOD) were highest in I100 plants, whereas catalase activity was the lowest. Hence P. umbellata is a shade species (sciophyte), a feature that should be considered in reforestation programs or in field plantings for production of medicinal constituents.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:51:58Z No. of bitstreams: 1 S0006-87052008000400010.pdf: 553849 bytes, checksum: 74e1d729a4bc16acb779b998a09ebfdf (MD5) Made available in DSpace on 2013-08-22T18:51:58Z (GMT). No. of bitstreams: 1 S0006-87052008000400010.pdf: 553849 bytes, checksum: 74e1d729a4bc16acb779b998a09ebfdf (MD5) Previous issue date: 2008-12-01 Made available in DSpace on 2013-09-30T17:48:59Z (GMT). No. of bitstreams: 2 S0006-87052008000400010.pdf: 553849 bytes, checksum: 74e1d729a4bc16acb779b998a09ebfdf (MD5) S0006-87052008000400010.pdf.txt: 25811 bytes, checksum: 58ff371f9fa6c011855f95b31fbb6516 (MD5) Previous issue date: 2008-12-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:21:50Z No. of bitstreams: 2 S0006-87052008000400010.pdf: 553849 bytes, checksum: 74e1d729a4bc16acb779b998a09ebfdf (MD5) S0006-87052008000400010.pdf.txt: 25811 bytes, checksum: 58ff371f9fa6c011855f95b31fbb6516 (MD5) Made available in DSpace on 2014-05-20T13:21:50Z (GMT). No. of bitstreams: 2 S0006-87052008000400010.pdf: 553849 bytes, checksum: 74e1d729a4bc16acb779b998a09ebfdf (MD5) S0006-87052008000400010.pdf.txt: 25811 bytes, checksum: 58ff371f9fa6c011855f95b31fbb6516 (MD5) Previous issue date: 2008-12-01 O uso das técnicas de fertirrigação em ambiente protegido vem aumentando no Brasil devido à praticidade de condução e redução dos custos de produção. Apesar dessas vantagens, salienta-se que esta prática também pode trazer riscos, principalmente pelo acúmulo de sais na superfície do solo e na região periférica do bulbo radicular. em caso de salinização do solo pelo manejo incorreto do sistema podem ocorrer alterações na disponibilidade de nutrientes, com conseqüências fisiológicas no desenvolvimento das plantas. Neste trabalho, utilizou-se o pimentão (Capsicum annuum L.) como planta-modelo para estudos da interferência da salinidade na nutrição das plantas, pela alteração da condutividade elétrica (CE) na solução do solo. Os resultados revelaram indícios de antagonismo entre nutrientes, notadamente entre as formas catiônicas em razão do aumento da concentração de KCl nos tratamentos com alta CE. A suplementação do solo com adubo orgânico não atenuou os efeitos do aumento da concentração salina e os valores extremos de CE interferiram drasticamente na produção. The use of fertigation techniques in greenhouse is increasing in Brazil due to the facilities and reduction of the costs of production. In spite of these advantages, it is pointed out that this practice can also bring risks, mainly for the accumulation of salts in the surface of the soil and in the peripheric root site of the bulb. In case of soil salinization due to incorrect handling of the system, it can happen alterations in the disponibility of nutrients, with physiological consequences to the development of the plants. In this research, the bell pepper (Capsicum annuum L.) was used as model for studies of the interference of the salinity in plant nutrition and yield. The obtained results revealed some antagonism among nutrients, especially among the cationic forms due to the increase of the KCl concentration in the treatments with high EC. The supplying of the soil with organic matter did not attenuate the effects of the increase of the saline concentration and the extreme values of EC interfered drastically in the production. UNESP FCA IB UNESP FCA Departamento de Recursos Naturais Universidade Tecnológica Federal do Paraná UNESP FCA IB UNESP FCA Departamento de Recursos Naturais