RESUMO Objetivou-se avaliar o efeito de doses de um biofertilizante de materiais vegetais (BMV) sobre o crescimento, produção e nutrientes no coentro ′Verdãoʼ. O BMV foi preparado com partes trituradas das espécies Flemingia macrophylla, Musa sp. e Azolla sp. O ensaio foi conduzido em cultivo protegido, em Argissolo Amarelo textura média (V%= 36,4). O delineamento experimental foi de blocos ao acaso com seis repetições. Além das doses do BMV (0, 5, 10, 15 e 30% em água), foi adicionado um tratamento com biofertilizante de esterco bovino (10% em água). Os biofertilizantes receberam ingredientes inorgânicos e foi incorporado esterco de galinha ao solo. As características avaliadas responderam às doses do BMV linearmente. Houve decréscimo da massa verde (GM) de plantas, de 1,43 a 0,88 kg/m2, que é o produto comercial, e da altura de planta em 31,33 a 24,02 cm, atribuídos à adstringência conferida pela Musa sp. ao biofertilizante, junto com escassez de N. A massa seca da parte aérea (DM) incrementou de 11,29 a 13,75 g/100 g devido às hastes mais fibrosas sob carência de N. Os teores dos nutrientes aumentaram (B e Zn), não variaram (N, S e Cu) ou decresceram (P, K, Ca, Mg, Fe e Mn) e os acúmulos incrementaram (N, S, K, B, Zn e Cu), decresceram (Fe) ou não se alteraram (P, Ca, Mg e Mn). A análise de componentes principais evidenciou a DM e os acúmulos de P, K, Ca, Mg e S com o mesmo sentido, além de antagonismo do N com o Ca e o Mg, atribuído à perda de N em pH alcalino, pelo fosfato natural no BMV. A DM e os acúmulos de B, Cu e Zn aumentaram concomitante ao passo que os acúmulos de Fe e de Mn não competiram. O biofertilizante de esterco superou o BMV em GM (1,38 e 1,21 kg/m2, respectivamente), assim como, nos acúmulos de N e K.

ABSTRACT The aim of this study was to evaluate the effect of doses of a biofertilizer, formulated with a mix of plants (BMV), on the growth, production and nutrients in coriander cultivar Verdão. The BMV was prepared with crushed parts of the species Flemingia macrophylla, Musa sp. and Azolla sp. The trial was carried out in a greenhouse, in Yellow Argissol, with medium texture (V= 36.4%). The experimental design was of randomized blocks with six replicates. Besides BMV doses (0, 5, 10, 15 and 30%, in water), an additional treatment with bovine manure biofertilizer was added (10% in water). Inorganic ingredients blended into biofertilizers as chicken manure were incorporated in soil of growing-beds. The evaluated traits responded to BMV doses linearly. A decrease in green mass (GM) of plants, from 1.43 to 0.88 kg/m2, which is the commercial product, and plant height, from 31.33 to 24.02 cm, was attributed to the astringency of Musa sp. in the biofertilizer, together with N shortage. The plant aerial part dry mass (DM) increased from 11.29 to 13.75 g/100 g due to fibrous stems under nitrogen deficiency. Nutrient contents increased (B and Zn), did not range (N, S, and Cu) or decreased (P, K, Ca, Mg, Fe and Mn) and accumulation increased (N, S, K, B, Zn and Cu), decreased (Fe) or did not change (P, Ca, Mg and Mn). The analysis of the principal components showed DM and accumulations of P, K, Ca, Mg and S in the same direction and antagonism of N with Ca and Mg, attributed to loss of N at alkaline pH, by natural phosphate (FN) in BMV. And also, DM, B, Cu and Zn accumulations increased concomitantly while accumulations of Fe and Mn did not compete. The manure biofertilizer surpassed the BMV in GM (1.38 and 1.21 kg/m2, respectively), as well as accumulations of N and K.

This study aimed to investigate the effect of silicon (Si) on the reduction of brown spot severity (BSS), caused by Bipolaris oryzae, and grain discoloration in several rice genotypes. An experiment was conducted in a greenhouse where eight genotypes were evaluated for their response to Si rates and decrease on BSS. The relationship between Si rates and BSS was linear negative. Additionally, a field experiment was conducted including forty-eight genotypes which were grown in upland conditions and evaluated for their response to Si rates and reduction on grain discoloration. The relationship between Si rates and grain discoloration was quadratic negative. Weight of filled grains per panicle increased as the Si rates in the soil increased. Genotypic differences for Si concentration in husk were evident for both non-amended and Si-amended plots. While the Si concentration in husk increased to all genotypes, there was no relationship between grain discoloration and Si concentration in husk for plants from non-amended and Si-amended plots. The genotype CAN-7024 with the highest resistance to leaf brown spot also showed the lowest grain discoloration in comparison to the genotypes Casado and Caqui.

Objetivou-se avaliar, no período chuvoso amazônico, o efeito do nitrogênio aplicado ao quiabeiro sob cultivo não-adensado e adubação residual. O ensaio foi conduzido na Embrapa Amazônia Ocidental, em Iranduba-AM, entre outubro/2010 e fevereiro//2011, em Argissolo Amarelo distrófico, textura média, utilizando-se covas com níveis residuais de fertilidade. O delineamento experimental foi em blocos casualizados com quatro repetições (duas linhas com quatro plantas, espaçadas de 1,5x1,0 m) e quatro tratamentos principais (ureia, em cobertura: 0,0; 20,0; 40,0 e 60 g planta-1 correspondendo a 0,0; 60,0; 120,0 e 180,0 kg ha-1 de N, respectivamente, em duas parcelas), com a cv Dardo. Além de dois tratamentos adicionais, representados pelo esterco de galinha (1,0 L por cova, com a cv Dardo) e pela cv Santa Cruz-47 (com 40 g planta-1 de ureia). As covas receberam micronutrientes e irrigação por gotejamento. As características avaliadas mostraram incrementos quadráticos com as doses de ureia. Os maiores valores da altura de planta (39,7 cm), do diâmetro de copa (86,2 cm), do número de frutos (36 unidades planta-1), da massa média de fruto (17,3 g), do número de colheitas no ciclo produtivo (26,4 unidades ciclo-1) e da produtividade (4051 kg ha-1) ocorreram com (g planta-1 de ureia): 48,3; 43,5; 38,5 g; 49,7; 32,7; e 40,5, respectivamente. As características originais concorreram com razoável equilíbrio para o desempenho geral da planta (CP1), evidenciando-se, secundariamente, antagonismo entre colheitas por ciclo e frutos por planta contra a massa média de fruto e o diâmetro de copa (CP2). O esterco de galinha proporcionou desempenho idêntico ao da ureia e sobressaiu ao tratamento sem ureia, para todas as características. A cv Santa Cruz-47 superou a cv Dardo somente para o diâmetro de copa e número de colheitas. A dose de máxima eficiência econômica foi 40,2 g de ureia planta-1 (120,6 kg ha-1 de N), com renda líquida por hectare de 2,09 toneladas de quiabo.

The aim of this study was to evaluate, in the Amazonian rainy season, the effect of nitrogen applied in okra under non-tightness grown and residual fertilization. The trial was carried out in the Embrapa Amazonia Ocidental, in Iranduba, Amazonas state, Brazil, between October/2010 and February/2011, in dystrophic Yellow Argisoil, medium texture, using pits with residual fertility. The experimental design was of randomized blocks with four repetitions (two lines with four plants, spacing of 1.5x1.0 m) and four main treatments (urea: 0.0; 20.0; 40.0 and 60.0 g plant-1 corresponding to 0.0; 60.0; 120.0 and 180.0 kg ha-1 of N, respectively, in two portions) using cv Dardo. Besides two additional treatments: chicken manure (1.0 L pit-1, with the cv Dardo) and cv Santa Cruz-47 (with urea rate of 40.0 g plant-1). Micronutrients in pits and dripping system irrigation were applied. All the studied traits had significant quadratic response with the increase of the urea rates. The highest estimated value for the plant height (39.7 cm), canopy diameter (86.2 cm), fruit number (36.0 un plant-1), fruit average mass (17.3 g), harvest number within production cycle (26.4 un cycle-1) and of the yield (4051 kg ha-1) were observed with (g plant-1 of urea): 48.3; 43.5; 38.5; 49.7; 32.7; and 40.5, respectively. Those original traits contributed reasonably poised for plant overall performance (PC1), but subordinate there was antagonism between harvest number and fruit number versus fruit average mass and canopy diameter (PC2). The chicken manure showed positive response compared to the control treatment, but didn't differ from urea rates for all these characteristics. When compared to cv Dardo, the cv Santa Cruz-47 only presented higher values to canopy diameter and number of harvests. The economical efficiency maximum dose was 40.2 g plant-1 of urea (120.6 kg ha-1 of N), with net income per hectare equal to 2.09 tons of okra fruits.