Effect of herbicides on yield components of sugarcane genotypes

Abstract

The most used weed control method in the sugarcane crop nowadays is the chemical. However, there is a great variation in selectivity of the genotypes regarding these products. The aim of this work was to evaluate the effect of herbicides on yield components of sugarcane genotypes. It was used a randomized blocks design, in a split-splot, with four replicates. In the plots were allocated the treatments: ametryn (2000 g ha^-1), trifloxysulfuron-sodium (22.5 g ha^-1), ametryn + trifloxysulfuron-sodium (1,463 + 37 g ha^-1) and the weeded control. In the subplots were the sugarcane genotypes: RB72454, RB835486, RB855113, RB855156, RB867515, RB925211, RB925345, RB937570, RB947520 and SP80-1816. Results show that herbicide phytotoxicity was higher in the RB835486 and RB855113 genotypes, when compared to the weeded control. Stalk diameter of ‘RB867515’, ‘RB925211’ and ‘SP8018-16’ was not affected when applying herbicides. The number of nodes per plant and the number of sugarcane plants per meter were affected by the use of trifloxysulfuron-sodium and ametryn + trifloxysulfuron-sodium in ‘RB867515’, ‘RB925211’ and ‘RB947520’. Sugarcane productivity of the RB855156 genotype was lower when applying the herbicides. Comparing all the genotypes among themselves and in the presence of the herbicides, it was observed that the ‘SP80-1816’ and the ‘RB867515’ were the most tolerant, standing out in relation to the others. Based on the results, it can be concluded that there is different tolerance of the sugarcane genotypes regarding the tested herbicides.