CRESCIMENTO DO FEIJÃO-CAUPI SOB EFEITO DOS HERBICIDAS FOMESA-FEN E BENTAZON+IMAZAMOX

Abstract

The objective of this study was to evaluate the g rowth of cowpea under the effect of herbicides fomesafen and bentazon + imazamox. The experiment w as conducted in a randomized block design, using th e split-plot scheme. In the plots were evaluated thre e weeds management systems (culture kept weeded by hoe- ing, with application of fomesafen (250 g ha -1 and the mixture of herbicides bentazon + imazamox (1.200 + 56 g ha -1 )) and in the subplots, 10 evaluation periods: 05, 12, 19, 26, 33, 40, 47, 54, 61 and 68 days after em er- gence (DAE). In each evaluation were collected rand omly in two of the four rows of the floor area of t he plots, three plants of cowpea to determine the following c haracteristics: leaf area, dry mass of leaves, stem , pods and total per plant, leaf area index, leaf area ratio, as well as the rates of absolute and relative growt h and of net assimilation. At harvest, we evaluated the number o f plants (stand), number of pods per plant, number of seeds per pod, 100-grain weight and grain yield. The fome safen caused severe intoxication in cowpea, delayin g flow- ering and harvest in seven days, while reducing pro ductivity. The mixture of the herbicides bentazon + ima- zamox did not affect the characteristics related to the growth of cowpea plants as well as the product ion compo- nents.