Milho voluntário EnlistTM: controle químico e qualidade fisiológica de sementes de soja e trigo

Abstract

EnlistTM technology in soybean and corn crops will be an important tool for weed management. However, soy and wheat crops grown in succession to corn are prone to the presence of volunteer EnlistTM maize plants, resulting from grains lost during harvesting, limiting control options and leading to losses in yield. The objective of the present work was to evaluate the chemical control of Enlist TM F2 volunteer maize with post emergent herbicides in EnlistTM soybean and wheat at different stages of development; and to evaluate the physiological quality of the seeds produced by the crop after exposure to the herbicides and the presence of volunteer maize plants. The experiments were conducted to field and greenhouse, to evaluate the efficiency of control and phytotoxicity to the crops, in a randomized complete block design, with four replications. The herbicides tested were: clethodim, haloxyfop-p-methyl, pinoxaden, imazethapyr and methyl chloransulam for soybean cultivation, and the herbicides pyroxsulam, clodinafoproparecil, pinoxaden and iodosulfuromethyl for wheat. The physiological quality of the seeds was evaluated in a completely randomized design with four replicates. The results demonstrated that the herbicide cletodim was efficient in the control of volunteer corn EnlistTM F2, without affecting the productivity and physiological quality of soybean seeds. The herbicides haloxyfop-p-methyl, pinoxaden and chloransulam-methyl are not efficient in the control of voluntary corn, negatively affecting the productivity components, without affecting the physiological quality of the soybean seeds. In the wheat crop, all evaluated herbicides were culture selective and did not efficiently control volunteer Enlist™ F2 maize plants, regardless of the application stage. The presence of volunteer maize plants caused a reduction in wheat yield and seed physiological quality.