Search

Phytate or phytic acid (PA), is a phosphorus (P) containing compound generated by the stepwise phosphorylation of myo-inositol. It forms complexes with some nutrient cations, such as Ca, Fe and Zn, compromising their absorption and thus acting as an anti-nutrient in the digestive tract of humans and monogastric animals. Conversely, PAs are an important form of P storage in seeds, making up to 90% of total seed P. Phytates also play a role in germination and are related to the synthesis of abscisic acid and gibberellins, the hormones involved in seed germination. Decreasing PA content in plants is desirable for human dietary. Therefore, low phytic acid (lpa) mutants might present some negative pleiotropic effects, which could impair germination and seed viability. In the present study, we review current knowledge of the genes encoding enzymes that function in different stages of PA synthesis, from the first phosphorylation of myo-inositol to PA transport into seed reserve tissues, and the application of this knowledge to reduce PA concentrations in edible crops to enhance human diet. Finally, phylogenetic data for PA concentrations in different plant families and distributed across several countries under different environmental conditions are compiled. The results of the present study help explain the importance of PA accumulation in different plant families and the distribution of PA accumulation in different foods.

Desde o início da pandemia de Covid-19 no Brasil foi observado que os profissionais de saúde que atuam na linha de frente em unidades de saúde em todo o país tiveram impactos significativos em sua saúde e rotina (LOTTA; et al. 2021). Adicionado a esse cenário, a identidade desses profissionais é vista popularmente de maneira estigmatizada (GOFFMAN, 1963) por estarem cotidianamente lidando de perto com pacientes contaminados com o coronavírus (Sars-CoV-2). Com base nisso, buscamos analisar nessa pesquisa os impactos que tem intensificado cada vez mais a vida e rotina desses profissionais durante a pandemia, tais como ansiedade, depressão e estresse (CAMPOS; et al. 2021). Nesse cenário de vulnerabilidade, a contaminação e a morte, respectivamente, têm se tornado cada vez mais comuns em suas rotinas; ao passo que se vêem, quase sempre, sem alternativas para subverterem a situação.

BACKGROUND Selenium (Se) is a nutrient for animals and humans, and is considered beneficial to higher plants. Selenium concentrations are low in most soils, which can result in a lack of Se in plants, and consequently in human diets. Phytic acid (PA) is the main storage form of phosphorus in seeds, and it is able to form insoluble complexes with essential minerals in the monogastric gut. This study aimed to establish optimal levels of Se application to cowpea, with the aim of increasing Se concentrations. The efficiency of agronomic biofortification was evaluated by the application of seven levels of Se (0, 2.5, 5, 10, 20, 40, and 60 g ha-1 ) from two sources (selenate and selenite) to the soil under field conditions in 2016 and 2017. RESULTS Application of Se as selenate led to greater plant Se concentrations than application as selenite in both leaves and grains. Assuming human cowpea consumption of 54.2 g day-1 , Se application of 20 g ha-1 in 2016 or 10 g ha-1 in 2017 as selenate would have provided a suitable daily intake of Se (between 20 and 55 μg day-1 ) for humans. Phytic acid showed no direct response to Se application. CONCLUSION Selenate provides greater phytoavailability than selenite. The application of 10 g Se ha-1 of selenate to cowpea plants could provide sufficient seed Se to increase daily human intake by 13-14 μg d-1 . © 2019 Society of Chemical Industry.

Made available in DSpace on 2019-10-06T17:14:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 This study aimed to assess the physiological and biochemical responses of cotton plants to manganese (Mn2+) nutrition. Four cotton genotypes (G1–TMG 47; G2–FM 975 WS; G3–TMG 11 WS and G4–IMA 8405 GLT) were grown in nutrient solution under two Mn2+ concentrations (2 and 200 µmol L−1) for 10 days. No visible symptoms of Mn2+ toxicity were observed in the genotypes tested. All genotypes showed a marked increase in leaf chlorophylls, pheophytins, carotenoids, sucrose and total sugars concentration in response to high Mn2+ in a nutrient solution. However, the net photosynthetic rate, stomatal conductance, internal carbon dioxide concentration and transpiration decreased in genotypes G1 and G2 growing under 200 µmol L−1. Antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) activities increased in genotypes G1, G3 and G4. Cotton genotypes showed an increased leaf antioxidant and sugar metabolism as a possible strategy to mitigate oxidative stress. The decrease in the net photosynthetic rate and stomatal conductance; the increased antioxidant enzymes activities (SOD, APX and GR); and the increase in leaf sucrose and total sugar concentration were the main physiological and biochemical responses in cotton plants to Mn2+ stress. Department of Crop Science and Social Economy São Paulo State University (UNESP) Department of Biosystems Engineering São Paulo State University (UNESP) Department of Crop Science and Social Economy São Paulo State University (UNESP) Department of Biosystems Engineering São Paulo State University (UNESP)

The use of growth regulators as a technique that can reduce plant height and thus strengthen stalks, which may be an option to eliminate or reduce plant lodging, thereby avoiding crop loss. However, there is a lack of information on the subject. The purpose of this study was to evaluate the effect of the dose (0; 37.5; 75.0; 112.5 e 150.0 g ha-1 active ingredient) and the application times of trinexapac-ethyl (sixth, seventh and eighth leaves), in a randomized complete block, in a 5x3 factorial scheme, with four replicates. The field experiment was performed during the 2016/17 crop season, in the experimental farm located in Selvíria, Mato Grosso do Sul State, Brazil, at Universidade Estadual Paulista- UNESP, Ilha Solteira, São Paulo State, Brazil - Campus. It is not recommended to apply the trinexapac-ethyl at eighth leaf, especially in the doses of 75.0; 112.5 and 150.0 g ha-1, since they generated the lowest values for yield parameters, thus reducing productivity, and providing greater number of unfilled grains. Taking into account the reduction in plant height, the minimization of lodging and grain yield, trinexapac-ethyl should be applied to the seventh leaf of the BRS Esmeralda rice at the dose of 75 g ha-1.

Made available in DSpace on 2021-06-25T10:25:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Dietary zinc (Zn) deficiency is widespread globally, and is particularly prevalent in low- and middle-income countries (LMICs). Cowpea (Vigna unguiculata (L.) Walp) is consumed widely in LMICs due to its high protein content, and has potential for use in agronomic biofortification strategies using Zn. This study aimed to evaluate the effect of Zn biofortification on grain nutritional quality of 29 cowpea genotypes. Zn application did not increase cowpea yield. In 11 genotypes sucrose concentration, in 12 genotypes total sugar concentration, and in 27 genotypes storage protein concentration increased in response to Zn supply. Fifteen genotypes had lower concentrations of amino acids under Zn application, which are likely to have been converted into storage proteins, mostly comprised of albumin. Phytic acid (PA) concentration and PA/Zn molar ratio were decreased under Zn application. Six genotypes increased shoot ureides concentration in response to Zn fertilization, indicating potential improvements to biological nitrogen fixation. This study provides valuable information on the potential for Zn application to increase cowpea grain nutritional quality by increasing Zn and soluble storage protein and decreasing PA concentration. These results might be useful for future breeding programs aiming to increase cowpea grain Zn concentrations through biofortification. São Paulo State University (UNESP) São Paulo State University (UNESP), Rua Domingos da Costa Lopes 780, Jd. Itaipu Embrapa Meio-Norte School of Biosciences University of Nottingham, Sutton Bonington The James Hutton Institute, Invergowrie National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University São Paulo State University (UNESP) São Paulo State University (UNESP), Rua Domingos da Costa Lopes 780, Jd. Itaipu FAPESP: 18/18936-6 CNPq: 309380/2017-0

Made available in DSpace on 2021-06-25T10:11:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) A better understanding of nitrogen (N) behavior and agronomic practices is needed to improve biological nitrogen fixation (BNF) and N use efficiency under field conditions. This study aims on investigating the potential for the use of biological agents that can fix atmospheric N and are related to multiple mechanisms benefits to improve cowpea (Vigna unguiculata (L.) Walp.) development and productivity, leading to a positive residual effect on wheat (Triticum aestivum L.) development. The study was set up under a no-till system in a Rhodic Haplustox, in a randomized complete block design, with four replicates. Treatments were tested in a full factorial design and included: i) three types of inoculation (without inoculation – control; Bradyrhizobium sp. inoculation (strains SEMIA 6462 and SEMIA 6463) – the conventional inoculation of cowpea; and Bradyrhizobium sp. combined with A. brasilense (strains Ab-V5 and Ab-V6) – the co-inoculation); and ii) five N rates (0 to 160 kg N ha−1) applied as urea-15N isotope. The residual effects of inoculations and N application rates applied during the cowpea growing season were evaluated on wheat (successor crop). Co-inoculation was found to increase cowpea grain yield by 40.5% and 14.1% compared to the control and Bradyrhizobium sp. inoculation when N was omitted and up to 37.6% and 50.8% when N was applied. Co-inoculation increased N use efficiency, N recovery and N accumulation on cowpea, leading to improved crop growth. The co-inoculation also provided a positive residual effect on wheat resulting in increased plant N accumulation, crop development, and greater wheat grain yield compared to the control (increase of 7.8%) and Bradyrhizobium sp. inoculated plants (increase of 5.8%). Co-inoculation was found to increase N use efficiency on cowpea by 216.5% and 35.5% and on wheat by 159.3% and 29.5% compared to control and Bradyrhizobium sp. inoculation, respectively. The fertilizer N recovery was, on average, 22.2% by cowpea, while fertilizer N recovery by wheat was

Made available in DSpace on 2021-06-25T10:10:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Low concentrations of selenium (Se) are beneficial for plant growth. Foliar Se application at high concentrations is toxic to plants due to the formation of reactive oxygen species (ROS). This study characterized Se toxicity symptoms using X-ray fluorescence (XRF) technique in response to foliar Se application in cowpea plants. Five Se concentrations (0, 10, 25, 50, 100 e 150 g ha−1) were sprayed on leaves as sodium selenate. The visual symptoms of Se toxicity in cowpea leaves were separated into two stages: I) necrotic points with an irregular distribution and internerval chlorosis at the leaf limb border (50–100 g ha−1); II) total chlorosis with the formation of dark brown necrotic lesions (150 g ha−1). Foliar Se application at 50 g ha−1 increased photosynthetic pigments and yield. Ultrastructural analyses showed that Se foliar application above 50 g ha−1 disarranged the upper epidermis of cowpea leaves. Furthermore, Se application above 100 g ha−1 significantly increased the hydrogen peroxide concentration and lipid peroxidation inducing necrotic leaf lesions. Mapping of the elements in leaves using the XRF revealed high Se intensity, specifically in leaf necrotic lesions accompanied by calcium (Ca) as a possible attenuating mechanism of plant stress. The distribution of Se intensities in the seeds was homogeneous, without specific accumulation sites. Phosphorus (P) and sulfur (S) were found primarily located in the embryonic region. Understanding the factors involved in Se accumulation and its interaction with Ca support new preventive measurement technologies to prevent Se toxicity in plants. São Paulo State University (UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, Postal Code 14884-900 University of São Paulo (USP), Av. Centenário, 303, São Dimas São Paulo State University (UNESP), Rua Domingos da Costa Lopes 780 São Paulo State University (UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, Postal Code 14884-900 São Paulo State University (UNESP), Rua Domingos da Costa Lopes 780

Made available in DSpace on 2020-12-12T02:09:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-15 University of Nottingham Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Selenium (Se) is a beneficial element to higher plants. Application of Se at low concentrations enhances the antioxidant metabolism reducing the reactive oxygen species (ROS) generated by plant membrane cells. This study aimed to evaluate how the application of Se in the forms sodium selenate and sodium selenite regulates ROS scavenging in field-grown cowpea plants. Seven Se application rates (0; 2.5; 5; 10; 20; 40 and 60 g ha−1) of each of the two Se forms were applied to plants via the soil. Photosynthetic pigments concentration, gas exchange parameters, lipid peroxidation by malondialdehyde (MDA) concentration, hydrogen peroxide concentration, activity of catalase (CAT, EC:1.11.1.6), glutathione reductase (GR, EC:1.6.4.2), ascorbate peroxidase (APX, EC:1.11.1.11) and Se concentration in leaves and grains were evaluated. In general, Se application led to a decrease in chlorophyll a concentration whilst leading to an increase in chlorophyll b, indicating conservation of total chlorophyll concentration. Application of 2.5 g ha−1 of Se as selenate provided a notable increase in total chlorophyll and total carotenoids compared to the other application rates. Selenate and selenite application decreased lipid peroxidation. However, each Se source acted in a different pathway to combat ROS. While selenate showed more potential to increase activity of APX and GR, selenite showed a higher potential to increase CAT activity. The negative correlation between CAT and GR is indicative that both pathways might be activated under distinct circumstances. The more prominent activity of CAT under high rates of selenite resulted in a negative correlation of this enzyme with chlorophyll a and carotenoids. Both selenate and selenite application increased sucrose and total sugars concentration in leaves of cowpea plants. Overall, these results indicate that application of Se in cowpea under field conditions stimulates distinct pathways to scavenge ROS. This could prove beneficial to mitigate oxidative stress during plant development. Departamento de Biologia Aplicada à Agropecuária Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), 14884-900 Terra Santa Agro S/A Departamento de Planejamento Agrícola, Avenida Miguel Sutil, 8800, 6° Andar, 78043-375 School of Biosciences The University of Nottingham, Leicestershire Faculdade de Ciências e Engenharia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Domingos da Costa Lopes 780, 17602-496 Departamento de Biologia Aplicada à Agropecuária Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), 14884-900 Faculdade de Ciências e Engenharia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Domingos da Costa Lopes 780, 17602-496 FAPESP: 18/18936–6 CNPq: 309380/2017–0

Made available in DSpace on 2020-12-12T02:02:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) This research was developed to investigate whether inoculation with Azospirillum brasilense in combination with silicon (Si) can enhance N use efficiency (NUE) in wheat and to evaluate and correlate nutritional and productive components and wheat grain yield. The study was carried out on a Rhodic Hapludox under a no-till system with a completely randomized block design with four replications in a 2 × 2 × 5 factorial scheme: two liming sources (with Ca and Mg silicate as the Si source and limestone); two inoculations (control - without inoculation and seed inoculation with A. brasilense) and five side-dress N rates (0, 50, 100, 150 and 200 kg ha−1). The results of this study showed positive improvements in wheat growth production parameters, NUE and grain yield as a function of inoculation associated with N rates. Inoculation can complement and optimize N fertilization, even with high N application rates. The potential benefits of Si use were less evident; however, the use of Si can favour N absorption, even when associated with A. brasilense. Therefore, studies conducted under tropical conditions with Ca and Mg silicate are necessary to better understand the role of Si applied alone or in combination with growth-promoting bacteria such as A. brasilense. São Paulo State University (UNESP) College of Engineering of Ilha Solteira Department of Plant Health Rural Engineering and Soils, P.O. BOX 15385-000, Av. Brasil Sul, 830 - Centro São Paulo State University (UNESP) College of Engineering of Ilha Solteira Department of Plant Health Rural Engineering and Soils, P.O. BOX 15385-000, Av. Brasil Sul, 830 - Centro CNPq: CNPq 305.299/2014-0 CNPq: CNPq 312359/2017-9

Made available in DSpace on 2020-12-12T01:10:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Selenium (Se) is an essential element for human and animal, although considered beneficial to higher plants. Selenium application at high concentration to plants can cause toxicity decreasing the physiological quality of seeds. This study aimed to characterize the Se toxicity on upland rice yield, seed physiology and the localization of Se in seeds using X-ray fluorescence microanalysis (μ-XRF). In the flowering stage, foliar application of Se (0, 250, 500, 1000, 1500, 2000 g ha−1) as sodium selenate was performed. A decrease in rice yield and an increase in seed Se concentrations were observed from 250 g Se ha−1. The storage proteins in the seeds showed different responses with Se application (decrease in albumin, increase in prolamin and glutelin). There was a reduction in the concentrations of total sugars and sucrose with the application of 250 and 500 g Se ha−1. The highest intensities Kα counts of Se were detected mainly in the endosperm and aleurone/pericarp. μ-XRF revealed the spatial distribution of sulfur, calcium, and potassium in the seed embryos. The seed germination decreased, and the electrical conductivity increased in response to high Se application rates showing clearly an abrupt decrease of physiological quality of rice seeds. This study provides information for a better understanding of the effects of Se toxicity on rice, revealing that in addition to the negative effects on yield, there are changes in the physiological and biochemical quality of seeds. São Paulo State University (UNESP), Rua Domingos da Costa Lopes 780, Postal Code 17602-496 São Paulo State University (UNESP), Postal Code 15.385-000 Federal University of Mato Grosso do Sul (UFMS), Rodovia MS-306 - Zona Rural, Postal Code 79560-000 Federal Institute of Southeast Minas Gerais Rua Monsenhor José Augusto, n. 204 - Bairro São José University of São Paulo - USP, Av. Centenário, 303, São Dimas, Postal Code 13400-970 São Paulo State University (UNESP), Rua Domingos da Costa Lopes 780, Postal Code 17602-496 São Paulo State University (UNESP), Postal Code 15.385-000 FAPESP: 15/05942-0 FAPESP: 15/19121-8 FAPESP: 16/19937-0 CNPq: 309380/2017-0

The objective of the present study was to evaluate agronomic biofortification with nitrogen (N) and selenium (Se) with the aim of increasing the daily Se intake by the population and the nutritional quality of the grain. A randomized block experimental design with a 5 × 2 factorial scheme was used; the factors were the five levels of N (0, 20, 40, 80, and 120 kg ha−1), applied as topdressing fertilization, and the two levels of Se (0 and 25 g ha−1). The reserve protein fractions in the seeds, glutelin, and globulin increased significantly when Se application was combined with N fertilization. Grain Se content varied from 0.03 to 0.35 mg kg−1, which was within the food safety limit of 0.3 mg kg−1 established by the Codex Alimentarius. The estimated daily Se intake originating from Se-biofortified rice varied between 2.05 and 24.7 μg per day, representing an increase from 3.72% to 44.9% of the daily Se requirement. Because the recommended Se daily intake for adults is 55 μg per day, the present study presents relevant information about agronomic biofortification to increase Se concentrations in edible plant parts, with possible benefits to human health.

Made available in DSpace on 2020-12-12T01:13:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-30 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) BACKGROUND: Selenium (Se) is an essential element for humans and animals. Rice is one of the most commonly consumed cereals in the world, so the agronomic biofortification of cereals with Se may be a good strategy to increase the levels of daily intake of Se by the population. This study evaluated the agronomic biofortification of rice genotypes with Se and its effects on grain nutritional quality. Five rates of Se (0, 10, 25, 50, and 100 g ha−1) were applied as selenate via the soil to three rice genotypes under field conditions. RESULTS: Selenium concentrations in the leaves and polished grains increased linearly in response to Se application rates. A highly significant correlation was observed between the Se rates and the Se concentration in the leaves and grains, indicating high translocation of Se. The application of Se also increased the concentration of albumin, globulin, prolamin, and glutelin in polished grains. CONCLUSION: Biofortifying rice genotypes using 25 g Se ha−1 could increase the average daily Se intake from 4.64 to 66 μg day−1. Considering that the recommended daily intake of Se by adults is 55 μg day−1, this agronomic strategy could contribute to alleviating widespread Se malnutrition. © 2019 Society of Chemical Industry. São Paulo State University (UNESP) University of São Paulo (USP) School of Biosciences University of Nottingham The James Hutton Institute São Paulo State University (UNESP) FAPESP: 15/11690-3 CNPq: 309380/2017-0

Evaluating seed quality with precision and accuracy is one of the priorities for obtaining high quality material. This study aimed to evaluate whether the variations in the performance of the accelerated aging test, in terms of exposure time and temperature, in the traditional form or in saline solution, would result in an efficient combination to evaluate the physiological quality of thyme seeds (Thymus vulgaris L.). The seeds were submitted to the tests of total germination, germination speed index, first germination count, seedlings emergence, seedling length, seedling dry mass, cold test, electrical conductivity, variations in the conduction of the accelerated aging test and the water content of the seeds was performed after each accelerated aging period. The treatments were the combination of temperatures (36, 38, 40 and 42 ºC), exposure time (24, 36, 48 and 72 hours) and two procedures (traditional and saline), with four replications for each batch. Traditional accelerated aging test at 42 ºC and 24 hours of exposure time, and saline solution accelerated aging test at 38 ºC and 24 hours of exposure time showed sensibility to evaluate physiological potential for thyme seed. For both saline solution and traditional accelerated aging test, the exposition time of 24 hours was efficient to evaluate physiological potential of thyme seeds.

A adubação tem proporcionado grandes avanços na produtividade e qualidade de pastagens, e entre os nutrientes, o nitrogênio (N) merece destaque por sua grande extração e aumento da produtividade das pastagens, porém, após sua aplicação ao solo, sofre influência do meio e pode ser perdido, quando mal manejado. Para minimizar tal problema, uma alternativa promissora é o uso de fertilizantes de eficiência aumentada, buscando-se reduzir tais perdas e proporcionar aumento de produtividade. Dessa forma, avaliou-se o efeito de fontes e doses de N na implantação de Urochloa brizantha cv. Xaraés (capim-xaraés) na produtividade e nos valores bromatológicos, em cultivo em condições do Cerrado. O experimento foi conduzido em área experimental no município de Rio Verde - GO, distribuídos em blocos ao acaso com quatro repetições, em esquema fatorial de 3x4. O primeiro fator foram três fontes de N (ureia convencional, ureia de eficiência aumentada e nitrato de amônio); o segundo fator foram quatro doses de N (0, 20, 40 e 80 kg N ha-1 corte-1). O uso da ureia convencional fez-se como a melhor alternativa para a cultura do capim-xaraés (P ≥ 0,05). A dose de nitrogênio recomendada é de 80 kg ha-1 por corte (P < 0,05), em vista do aumento da produtividade de massa seca, e à melhoria da qualidade bromatológica do capim-xaraés.

Entre os fatores agrícolas, a adubação tem proporcionado grandes avanços na produtividade e qualidade de pastagens, sendo que o nitrogênio (N) merece destaque por sua grande extração e aumento da produtividade de gramíneas, entretanto, sofre influência do meio e pode ser perdido se mal manejado. Para minimizar tal problema, uma alternativa apontada como promissora é o uso de fertilizantes de eficiência aumentada. Dessa forma, objetivou-se com o trabalho avaliar o efeito de fontes e doses de N na implantação do Urochloa brizantha cv. Xaraés (capim-xaraés), em cultivo nas condições do Cerrado. O experimento foi conduzido em área experimental no município de Rio Verde – GO, Brasil, com delineamento em blocos ao acaso com quatro repetições, em esquema fatorial de 3x4. Sendo três fontes de N (ureia convencional, ureia de eficiência aumentada e nitrato de amônio); e quatro doses de N (0, 20, 40 e 80 kg N ha-1 corte-1). O uso da ureia convencional fez-se como a melhor alternativa para a cultura do capim-xaraés, a ureia revestida não foi considerada de maior eficiência. A dose de nitrogênio recomendada é de 80 kg ha-1 por corte, em vista da melhoria nutricional da matéria seca da parte aérea.

Made available in DSpace on 2018-12-11T17:18:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-06-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Selenium (Se) is considered a beneficial element for plants; however, in high concentrations, it causes negative effects on plant physiology and development. This study reports the first physiological, nutritional, and ultrastructural description of Se toxicity in cowpea growing under field conditions. Selenium was supplied as a foliar application of sodium selenite at varying concentrations (0, 50, 100, 200, 400, 800, 1200, and 1600 g ha−1). An increased yield was observed with the application of 50 g ha−1 Se. Application of concentrations higher than 50 g ha−1 caused leaf toxicity. Increased lipid peroxidation and hydrogen peroxide concentration and reduced total sugars, sucrose, and carotenoid concentration were observed at highest doses tested (1200 and 1600 g ha−1). Applications of more than 50 g ha−1 Se reduced the phloem diameter, caused chlorosis of the leaf blade with a coalescence of lesions, and caused pink salt deposits to appear. Lesions were observed mainly near the trichomes on the adaxial surface of the leaf blade. An analysis of the element distribution with microprobe X-ray fluorescence spectrometry (μ-XRF) revealed accumulation of Se, calcium (Ca), potassium (K), copper (Cu), and manganese (Mn) near the primary vein and in the necrotic brown areas of the leaf lesions. In contrast, Na was homogeneously distributed in the leaf tissue. São Paulo State University – UNESP, Ilha Solteira, Postal Code 15.385-000 São Paulo State University – UNESP, Tupã Postal Code 17602-496, SP University of São Paulo – USP, Postal Code 13416-000, SP The James Hutton Institute, Invergowrie School of Biosciences The University of Nottingham, Sutton Bonington São Paulo State University – UNESP, Ilha Solteira, Postal Code 15.385-000 São Paulo State University – UNESP, Tupã Postal Code 17602-496, SP FAPESP: 2015/19121-8 FAPESP: 2016/19773-8

Eucalyptus cultivation has expanded considerably in Brazil, especially in regions where soils have low fertility, as in the Brazilian Cerrado (Brazilian Savannah). In order to achieve high yield, it is necessary to know the appropriate time and place to perform the soil management, and to assist in this decision-making process, mathematical and computational models has been used and are a promising alternative. The objective of this study was to model the influence of plant and soil physical-chemical attributes on Eucalyptus camaldulensis cultivation in an Oxisol (Latossolo Vermelho distrófico), with clayey texture with the purpose of demonstrating specific management areas closely associated with eucalyptus development. An experimental grid of approximately 2 hectares (ha) containing 40 sampling points were installed and later soil and plant attributes were collected for the determination of physical and chemical attributes in the 0-0.20 m and 0.20-0.40 m layers in Selvíria, MS, Brazil. The results were analyzed using classical and geostatistical statistics. The spatial dependence varied according to the physical attribute evaluated and the depth of sampling. In addition to the vertical variability, there was also horizontal variability between depths, since for the same attribute the range was different between the sampled layers.

Boron is one of the most limiting micronutrients in grains production system in Brazil. In this way, the objective was to evaluate the effect of forms of application and doses of boron in irrigated wheat grain yield evaluating the economic terms in Cerrado region. The experiment was conducted in no-tillage system in an Oxisol with clay texture in Selvíria, MS, Brazil. The experimental design was a randomized block design with four replicates, arranged in a 4 × 3 factorial scheme: four doses of boron (0, 1, 2 and 4 kg ha-1) with boric acid source (B = 17%); and three apllication forms: a) in desiccation of the predecessor straw, together with herbicide; b) at the time of sowing, in soil along with the formulated fertilization seeding and c) via leaf tissue with the application of post emergent herbicide. The application of 2 kg ha-1 provides greater grain yields, but the highest economic return was obtained at the dose of 1 kg ha-1, with application in soil, ensuring profitability from production of irrigated wheat in the Cerrado.

Azospirillum brasilense plays an important role in biological nitrogen fixation (BNF) in grasses. However, further studies are needed to define how much mineral N can be applied while simultaneously maintaining BNF contribution and maximizing crop yield and to determine the impact of these practices on soil fertility. Thus, we aimed to investigate the effect of inoculation with A. brasilense, in conjunction with varying N doses and sources in a Cerrado soil, on soil chemical attributes after two years of irrigated wheat production. The experiment was initiated in Selvíria - MS under no-tillage production in an Oxisol in 2014 and 2015. The experimental design was a randomized block design with four replications, and treatments were arranged in a 2 x 5 x 2 factorial arrangement as follows: two N sources (urea and Super N - urea with inhibitor of the enzyme urease NBPT (N - (n-butyl thiophosphoric triamide))), five N rates (0, 50, 100, 150 and 200 kg ha-1), and with or without seed inoculation with A. brasilense. The increase in N rates did not influence the chemical soil attributes. Super N acidified the soil more compared to urea. A. brasilense inoculation reduced the effect of soil acidification in intensive irrigated wheat cultivation; however, the base extraction was higher, resulting in a lower soil CEC after cultivation with inoculation. Therefore, the cultivation of wheat inoculated with A. brasilense was not harmful to soil fertility because it did not reduce the base saturation and organic matter content (P, K, Ca, Mg, and S).

The pastures of western Sao Paulo are grown on low fertility soils, therefore, forage has low nutritional value resulting low dry matter yield (DMY).Thus, phosphorus fertilization and analysis of its residual are important for livestock, as it interferes the development speed of forage grasses, allowing better use of area and helping to pasture maintenance, in addition maintaining DMY at adequate levels. This study aimed at evaluating the effect of sources and rates of phosphorus applied in Marandu palisadegrass (Urochloa brizantha cv. Marandu) maintenance to reduce its seasonality, in order to achieve higher yield of these plants. A randomized block de­sign used with 16 treatments and four replications in a 4 x 4 factorial, consisted of four sources of P (Phosphate from Araxa, Reactive phosphate from Arad, Simple superphosphate and thermophosphate) at rates (0, 100, 200 and 300 kg ha -1 of P 2 O 5 ). A total of ten cuts were performed. DMY was quantified and contents of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) were determined and P concentrations of Marandu palisadegrass shoot. The residual of sources and P rates did not influence DMY, CP, NDF and ADF contents and P concentrations of plant tissue, indicating that for maintaining Marandu palisadegrass P levels in soil were sufficient and this forage is not demanding regarding this nutrient.

Dietary zinc (Zn) deficiency is widespread globally, and is particularly prevalent in low- and middle-income countries (LMICs). Cowpea (Vigna unguiculata (L.) Walp) is consumed widely in LMICs due to its high protein content, and has potential for use in agronomic biofortification strategies using Zn. This study aimed to evaluate the effect of Zn biofortification on grain nutritional quality of 29 cowpea genotypes. Zn application did not increase cowpea yield. In 11 genotypes sucrose concentration, in 12 genotypes total sugar concentration, and in 27 genotypes storage protein concentration increased in response to Zn supply. Fifteen genotypes had lower concentrations of amino acids under Zn application, which are likely to have been converted into storage proteins, mostly comprised of albumin. Phytic acid (PA) concentration and PA/Zn molar ratio were decreased under Zn application. Six genotypes increased shoot ureides concentration in response to Zn fertilization, indicating potential improvements to biological nitrogen fixation. This study provides valuable information on the potential for Zn application to increase cowpea grain nutritional quality by increasing Zn and soluble storage protein and decreasing PA concentration. These results might be useful for future breeding programs aiming to increase cowpea grain Zn concentrations through biofortification. Made available in DSpace on 2021-05-18T14:27:23Z (GMT). No. of bitstreams: 1 Agronomic1-s2.0-S0981942821000875-main.pdf: 8793653 bytes, checksum: 80493066af6e43a23e3a891bb7f58d2d (MD5) Previous issue date: 2021

Backgorund: Cowpea is a crop widely used in developing countries due its rusticity. Besides its rich genotypic variability, most breeding programs do not explore its potential to improve elements uptake. Selenium (Se) is a scarce element in most soils, resulting in its deficiency being common in human diets. This study aimed to evaluate the interaction between biofortification with Se and genotypic variation in cowpea, on the concentrations of Se in roots, leaves + stem and grains. Made available in DSpace on 2021-05-19T14:25:54Z (GMT). No. of bitstreams: 1 Silva-et-al-2021.pdf: 3044737 bytes, checksum: 29458aeffe6c5df46b75531a42a63207 (MD5) Previous issue date: 2021