Espectros de raios-x em MEV indicam associação entre Al e Si em plantas acumuladoras de Al do Cerrado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fenologia remota: uso de imagens digitais no acompanhamento fenológico de plantas em uma área de cerrado sensu stricto, no município de Itirapina, São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Nutrição mineral e escleromorfismo foliar de grupos funcionais e comunidades vegetais savânicas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Composições e métodos para direcionar a expressão de genes usando o promotor do gene da família das isoflavonas de plantas de café

A presente invenção compreende a descrição de uma nova sequência regulatória provida para direcionar a expressão de uma sequência de nucleotideo, tal como genes estruturais, em folhas de plantas, incluindo monocotiledóneas e dicotiledóneas. Mais especificamente a invenção refere-se a sequências regulatórias de polinucleotídeos isoladas de plantas de café que são capazes de inicial- e acionar a transcrição de polinucleotídeos, e ao uso destas sequências regulatórias no direcionamento de transcrição de polinucleotídeos endógenos e/ou heterólogos para tecidos foliares e produção de polipeptídeos.

Reação de híbridos de milho à mancha-de-macrospora

Macrospora leaf spot, caused by the fungus Stenocarpella macrospora, has shown to be frequent and important among corn fields in Brazil. Genetic resistance is one of the main strategies to control corn leaf diseases. In Brazil, there is scarce information on the resistance of hybrids to Stenocarpella macrospora. The aim of this study was to evaluate the reaction of 25 corn hybrids to macrospora leaf spot. The experiment was conducted in 2011, in a greenhouse under controlled temperature and relative humidity conditions. Experimental design was completely randomized, with five replicates, each experimental unit consisting of a pot with five plants. Inoculation was done in the V2 growth stage (two fully expanded leaves), and the whorl of each plant received 2.0 mL suspension of 1.8 x 10(4) conidia mL-1 pathogen. The four used fungal isolates were obtained from infected crop residues at the municipalities Lages and Quilombo, Santa Catarina State, and Campinas do Sul and Vacaria, Rio Grande do Sul State. Disease severity was assessed at 21 days after inoculation in the V4 stage (four fully expanded leaves). No tested hybrid was totally resistant to the fungus S. macrospora. There was a significant difference in the disease severity between hybrids and fungal isolates. Hybrids inoculated with Quilombo isolate showed four reaction groups, while the isolates Vacaria, Lages and Campinas do Sul showed two groups. Some hybrids had varied behaviors against the isolates, suggesting different aggressiveness levels. There were hybrids that showed similar reaction to the isolates, suggesting greater stability for macrospora leaf spot.

Coberturas vegetais e doses de nitrogênio em trigo sob sistema plantio direto

The application of conservation practices in production systems is essential to the sustainability of the agricultural production capacity. The use of different cover crops can reduce the need of topdressing nitrogen fertilizers in wheat crops. This study aimed at evaluating the influence of cover crops residues (millet, sunn hemp, pigeon pea, millet + sunn hemp, millet + pigeon pea and fallow ground), grown previously to the summer crop (rice), and topdressing nitrogen doses (0 kg ha-1, 25 kg ha-1, 50 kg ha-1, 75 kg ha-1, 100 kg ha-1 and 125 kg ha-1), in the development and yield of wheat under no-tillage system. The experiment was carried out in Selvíria, Mato Grosso do Sul State, Brazil, in a Red Oxisol, in 2009/2010 and 2010/2011. The experimental design was randomized blocks, in a 6x6 factorial scheme. The cover crops developed during August/October (2009/2010) and September/November (2010/2011), previously to the summer crop, with the chemical desiccation performed respectively at 73 and 55 days after sowing. The wheat (winter) was sown in May, in both periods, and harvested at 113 (2009/2010) and 106 (2010/2011) days after emergence. The cover crops residues of pigeon pea, sunn hemp and millet + sunn hemp, preceding wheat, provided higher wheat yields, relatively to the fallow ground. The wheat yield showed a quadratic response to the increase in the nitrogen availability, reaching higher yields with the nitrogen doses estimated in 113 kg ha-1 (2010) and 98 kg ha-1 (2011).

Physiological indexese macro- and micronutrients in plant tissue and essential oil of Mentha piperita L. grown in nutrient solution with variation in N, P, K and Mg levels

Mentha piperita L. is an aromatic and medicinal species of the family Lamiaceae, known as mint or peppermint, and its leaves and branches produce essential oil rich in menthol. This study aimed to evaluate physiological indexes, macro- and micronutrients inthe shootsand essential oil of Mentha piperita L. grown in nutrient solution number 2 of Hoagland and Arnon (1950) with different N, P, K and Mg levels. Shoot length, dry mass of the different organs, total dry mass, leaf area, essential oil yield and composition, and macronutrient (N, P, K, Mg, Ca, S) and micronutrient (Mn, Cu, Fe, Zn) contents in the shoot were evaluated. Plants treated with 65%N/50%P/25%K/100%Mg had a tendency towards longer shoot, greaterroot and leaf blade dry masses, higher essential oil yield, higher menthol levels and lower menthone levels. The results showed that Mentha can be grown in nutrient solution by reducing 65% N, 50% P, 25% K and 100% Mg. This solution had better development compared to the other tested treatments. Therefore,we recommendMentha piperita L. to be grown with such nutrient levels.

Biological aspects of Aphis gossypii Glöver, 1877 (Hemiptera: Aphididae) on colored lint cotton cultivars

This paper outlines the results of a study into the biological aspects of Aphis gossypii Glöver on colored cotton cultivars through the construction of life tables. In addition, we evaluate the influence of density of gossypol glands and trichomes of leaves on the biology of the aphid. Tests were conducted in a climate chamber at 25 ± 2°C, with relative humidity (RH) at 70 ± 10%, and a photophase of 12 hours, using the cultivars BRS Rubi, BRS Safira, and BRS Verde. Newly hatched nymphs were individually isolated in petri dishes containing leaf discs of cotton cultivars on a layer of water-agar (1%) of approximately 5 mm thick. An evaluation of the trichomes and gossypol gland densities of the cotton leaf plants was performed under a stereomicroscope, delimited to an area of 1 cm², and a count and identification of those on the surface was made. The feed substrates that were evaluated influenced the nymphal stage of A. gossypii. BRS Verde provided the shortest duration and BRS Safira was the longest during this phase. The cultivar BRS Verde, with the lowest density of trichomes, provided a large number of nymphs and led to a higher net reproductive rate (R0). Given these results, conclusions can be drawn that the colored cotton cultivars influence the duration of nymphal and adult stages of A. gossypii. The cultivar with a high density of trichomes on leaves (BRS Safira) adversely affects the fertility parameters of A. gossypii.

Estimativa da área foliar de Euphorbia heterophylla

Leaf area estimate may contribute to understand the relationships of interference among weeds and crops. The objective of this research was to obtain a mathematical equation to estimate the leaf area of Euphorbia heterophylla based on linear measures of the leaf blade. Correlation studies were carried out using the real leaf area and leaf length (C) and the maximum leaf width (L) of 200 leaf blades which were collected from several agroecosystems at Universidade Estadual Paulista in Jaboticabal, SP, Brazil. The evaluated statistic models were: linear Y = a + bx; simple linear Y = bx; geometric Y = ax b; and exponential Y = ab x. All of the evaluated models can be used for E. heterophylla leaf area estimation. The simple linear regression model is suggested using C*L and taking the linear coefficient equal to zero. Thus, an estimate of the leaf area of E. heterophylla can be obtained using the equation Af' = 0.6816*(C*L).

Modelagem geoestatística das incertezas da distribuição espacial do fósforo disponível no solo, em área de cana-de-açúcar

Phosphorus is one of the limiting nutrients for sugarcane development in Brazilian soils. The spatial variability of this nutrient is great, defined by the properties that control its adsorption and desorption reactions. Spatial estimates to characterize this variability are based on geostatistical interpolation. However, inherent uncertainties in the procedure of these estimates are related to the variability structure of the property under study and the sample configuration of the area. Thus, the assessment of the uncertainty of estimates associated with the spatial distribution of available P (Plabile) is decisive to optimize the use of phosphate fertilizers. The purpose of this study was to evaluate the performance of sequential Gaussian simulation (sGs) and ordinary kriging (OK) in the modeling of uncertainty in available P estimates. A sampling grid with 626 points was established in a 200-ha experimental sugarcane field in Tabapuã, São Paulo State. The sGs algorithm generated 200 realizations. The sGs realizations reproduced the statistics and the distribution of the sample data. The G statistic (0.81) indicated good agreement between the values of simulated and observed fractions. The sGs realizations preserved the spatial variability of Plabile without the smoothing effect of the OK map. The accuracy in the reproduction of the variogram of the sample data obtained by the sGs realizations was on average 240 times higher than that obtained by OK. The uncertainty map, obtained by OK, showed less variation in the study area than that obtained by sGs. Thus, the evaluation of uncertainties by sGs was more informative and can be used to define and delimit specific management areas more precisely.

Adubação fosfatada no crescimento inicial e na nutrição de mudas de pinhão-manso

Physic nut (Jatropha curcas L.) is a perennial oilseed species that has aroused economic interest for biodiesel production. Among other factors, it is essential to determine the nutritional demands of this species to facilitate raising it as a crop. This study aimed to evaluate the early growth and mineral nutrition of physic nut, as well as soil fertility, as affected by phosphorus fertilization. The study was carried out in a plastic greenhouse in a completely randomized block experimental design with four replicates. The plants were grown in plastic pots filled with 50 dm³ of Latossolo Vermelho (Rhodic Hapludox). Application rates of 0, 50, 100, 150 and 200 mg dm-3 of P were tested, plus a control. Evaluations of plant height and root collar diameter were performed monthly. The experiment was ended 150 days after transplant of the seedlings, at which time leaf area, dry weight, leaf contents and total accumulation of macro- (N, P, K, Ca, Mg and S) and micronutrients (B, Cu, Fe, Mn and Zn) were performed, and soil chemical properties were analyzed. We concluded that absence of P fertilization alone is as limiting to early growth of physic nut as simultaneous absence of soil amendment and fertilization. The rate of 57 mg dm-3 of P may be recommended for initial growth of physic nut. The total accumulation of nutrients in physic nut seedlings exhibited the following order: K>N>Mg>Ca>P>S>Fe>Mn>B>Zn>Cu. Phosphorus fertilization resulted in increased soil cation exchange capacity (CEC).

Fontes e doses de nitrogênio na cultura da Brachiaria brizantha cv. xaraés sob condições edafoclimáticas de cerrado

Pós-graduação em Agronomia - FEIS

Consórcio entre milho e leguminosas, produção de palha e manejo do nitrogênio no feijão “de inverno” em região com verão chuvoso e inverno seco

Pós-graduação em Agronomia - FEIS

Níquel em solo e plantas de milho cultivadas em área tratada com lodo de esgoto durante 15 anos consecutivos

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Nutrição potássica em soqueira de cana-de-açúcar colhida sem queima

Pós-graduação em Agronomia (Ciência do Solo) - FCAV