Herbicide and nematicide interaction in sugarcane crops

Abstract

Sugarcane has great economic importance in Brazil. In order to maintain its yield, several biotic and abiotic factors can have a positive or negative influence. Among them, it is possible to mention weeds, nematodes and the synergistic action among pesticides in order to control both. Thus, the present work had the objective to study the interaction between herbicides and nematicides used in sugarcane crop. The experimental design was completely randomized, in a 5 x 3 factor scheme, with four replications. The first factor corresponds to sulfentrazone (800 g ha^-1 a.i.), saflufenacil (98 g ha^-1 a.i.), diuron + hexazinone (1170 g ha^-1 a.i. + 330 g ha^-1 a.i.), amicarbazone (1050 g ha^-1 a.i.) plus the control sample; the second factor corresponds to the nematicides benfuracarb (2000 g ha^-1 a.i.) and carbofuran (1750 g ha^-1 a.i.) plus the control sample. Nematicides were applied in contact with billets and herbicides applied during the pre-emergence of the crop; this was perfomed on the RB867515, RB975201 and RB975952 sugarcane varieties. Evaluations of phytotoxicity were performed at 7, 15, 30, 45 and 60 after emergence (DAE) of the crop. During the last evaluation, the biometric parameters of height, leaf area and dry biomass of the aerial part were determined. All plants recovered after 60 DAE, and in treatments with the use of sulfentrazone higher intoxication symptoms were observed. As for the biometric parameters evaluated at 60 DAE, there was no significant interaction for herbicide and nematicide factors, but there was a difference between treatments in each variety.