Evaluation of intoxication caused by post-emerging herbicides in cassava culture in two times of application

Abstract

This study aimed to evaluate the selectivity of post-emergent herbicides in cassava in two application times. The experiments were carried out in a greenhouse at the Federal University of Tocantins - UFT, Campus Gurupi. The experimental designed was completely randomized arranged in a 5x2 factorial scheme, composed by the combination of 5 herbicide molecules with different mechanisms of action (mesotrione, carfentrazone-ethyl, chlorimuron-ethyl, nicosulfuron and imazethapyr) applied in two seasons, 30 and 45 days after emergence (DAE), with four repetitions. The cultivar used was “Cacau melhorada”. The visual intoxication of the culture was evaluated. The results obtained were subjected to analysis of variance, by the F test, with the averages analyzed statistically by the LSD mean test, at 5% probability. The treatments based on mesotrione, and chlorimuron-ethyl were not toxic to the culture, promoting results similar to those observed for control. There were differences in the level of tolerance to the studied herbicides, between the times of application of the herbicides.

Evaluación de la selectividad y efectividad de distintos herbicidas para el control de malezas en el cultivo de mandioca (<i>Manihot esculenta</i> Crantz) en Corrientes

“…Por consiguiente, los resultados indicados anteriormente nos permiten inferir que la aplicación de manera dirigida con pantalla realizada en este experimento, permite otorgar una selectividad por emplazamiento diferencial como lo indicanOrioli et al (2014) para los tres tratamientos de control de malezas indicados anteriormente.El tratamiento de control de malezas con el herbicida Imazetapir, fue el único de los herbicidas de aplicación post-emergente dirigida con el que se registraron síntomas fitotóxicos. Dichos síntomas fueron similares a los citados enAgostinetto et al (2002) y Machado Filho et al (2020 quienes hicieron una aplicación de cobertura total sobre la planta de mandioca. Esto indica que ni aún con la aplicación dirigida el Imazetapir logra generar una selectividad por emplazamiento diferencial.…”