ASSOCIATION OF PESTICIDES WITH SOYBEAN LEAF MICRONUTRIENTS CONTENTS AND SEEDS YIELD AND PHYSIOLOGIC QUALITY ASSOCIAÇÃO DE AGROTÓXICOS AOS TEORES FOLIARES DE MICRONUTRIENTES E À PRODUTIVIDADE E QUALIDADE FISIOLÓGICA DE SEMENTES DE SOJA

Abstract

<p style="margin-bottom: 0cm; font-style: normal; font-weight: normal; line-height: 120%; text-decoration: none;" lang="pt-BR"><span style="color: #000000;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;">Glyphosate effects on leaf micronutrients contents of transgenic soybean have been widely reported, however, little is known about these effects associated with other pesticides. The objective of this study was to evaluate the physiologic quality and yield of soybean seeds, as well as leaf micronutrients contents, according to weed control methods. Ten RBD treatments were arranged in a split-plot scheme with four replications. The application or non-application of endosulphan + tebuconazole was evaluated in the plots, while the weeds control methods were assessed in the subplots (weeded control; non-weeded control; single application of glyphosate (1,080 g ha^-1) and fomesafen + fluazifop-?-butil (180 + 225 g ha^-1), both at 15 DAE; and sequential application of glyphosate (1,080 g ha^-1) at 15, 30, and 45 DAE). After harvesting, the soybean seeds were sampled, in order to evaluate their germination, vigor, and yield. Copper and manganese contents were only influenced by the sequential application of glyphosate, associated with endosulphan + tebuconazole. The cold test germination was reduced in seeds of plants treated with fomesafen + fluazifop-p-butil associated with endosulphan + tebuconazole. Among the treatments without endosulphan + tebuconazole, the sequential application of glyphosate promoted the highest 100-seeds weight, as well as, when associated with endosulphan + tebuconazole, reduced the leaf concentrations of Cu and Mn, however, it improved seeds germination and showed no effects on seeds vigor, when compared with the weeded soybean.</span></span></span></p><p style="margin-bottom: 0cm; font-style: normal; font-weight: normal; line-height: 120%; text-decoration: none;" lang="pt-BR"><span style="color: #000000;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">Efeitos do glyphosate nos teores foliares de micro-nutrientes de soja transgênica têm sido amplamente relatados, porém, pouco se sabe sobre seus efeitos associados a outros agrotóxicos. Objetivou-se, neste trabalho, avaliar a produção e a qualidade fisiológica de sementes de soja, bem como os teores de micronutrientes nas folhas, em função de métodos de controle de plantas daninhas. Foram avaliados dez tratamentos DBC, em esquema de parcelas subdivididas, com quatro repetições. Nas parcelas, avaliou-se o efeito da aplicação ou não de endossulfan + tebuconazole e, nas subparcelas, o efeito dos métodos de controle de plantas daninhas (testemunha não capinada; testemunha capinada; aplicação única de glyphosate (1.080 g ha</span></span></span></span></span></span><span style="color: #000000;"><span style="text-decoration: none;">^{<span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">-1</span></span></span></span>}</span></span><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">) e fomesafen + fluazifop-?-butil (180 + 225 g ha</span></span></span></span></span></span><span style="color: #000000;"><span style="text-decoration: none;">^{<span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">-1</span></span></span></span>}</span></span><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">), ambas aos 15 DAE; e aplicação sequencial de glyphosate (1.080 g ha</span></span></span></span></span></span><span style="color: #000000;"><span style="text-decoration: none;">^{<span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">-1</span></span></span></span>}</span></span><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">), aos 15, 30 e 45 DAE). Após a colheita da soja, as sementes foram amostradas, para avaliar a sua germinação, vigor e produtividade. Os teores de manganês foram influenciados pela aplicação sequencial de glyphosate, associada ao endossulfan + tebuconazole. A germinação do teste de frio foi reduzida em sementes de plantas tratadas com fomesafen + fluazifop-p-butil, em associação com endossulfan + tebuconazole. Dentre os tratamentos sem endossulfan + tebuconazole, a aplicação sequencial de glyphosate promoveu a maior massa de cem sementes, bem como, associada à mistura endossulfan + tebuconazole, diminuiu os teores foliares de Cu e Mn, porém, melhorou a germinação e não influenciou no vigor das sementes, em relação à soja capinada.</span></span></span></span></span></span></span></span></span></p>

Keywords

• Glycine Max L.
• germinação
• herbicida.