Avaliação de variedades RB (República do Brasil) de cana-de-açúcar em relação ao ataque de pragas

Abstract

In this work, several varieties RB (Republic of Brazil) of sugar cane were compared in relation to the attack of Diatraea spp. (Lepidoptera: Crambidae) Mahanarva spp. (Hemiptera: Cercopidae) and Telchin licus licus (Drury, 1773) (Lepidoptera: Castniidae). Two systems of cultivation were used, rainfed and irrigated. The varieties studied in the rainfed cultivation were as follows: RB72454, RB867515, RB971755, RB951541, RB931003, RB92579, RB863129, and RB93509. For the irrigated system, the variety RB98710 was also included. In the rainfed system, with all varieties in combined analysis, it was found that the varieties RB867515, RB863129, RB93509, RB92579 and RB931003 showed the lowest percentage of external damage by Diatraea spp. In the irrigated system, the varieties RB72454, RB92579 and RB93509 were the least infested. In both cropping systems, the complex borer/rottenness, assessed at harvest, indicated no significant differences between the varieties in respect of damages by Diatraea spp. The results for Mahanarva spp. in the rainfed cultivation, indicated the varieties RB72454, RB863129 and RB951541 as the least infested. For irrigated crop, the results were statistically similar, it was not possible to identify a variety with striking characteristic of preference by the pest. The results of % infestation of T. licus licus indicated that, in the two cropping systems, the varieties did not differ statistically. In both cropping systems, the values o f % of internal damage by Diatraea spp. and % infestation by T. licus licus did not show any significantly correlation with the agroindustrial parameters evaluated.