Infestação de Bemisia tabaci biótipo b em cultivares de algodoeiro e seus efeitos na produtividade e qualidade de fibra

Abstract

Monitoring and evaluating the critical periods of the Bemisia tabaci (Gennadius) biotype B attack during the cotton cycle is important, as well as determining the limits of population density in the phenological stages of the crop, to avoid problems in productivity and fiber quality. The experiments were carried out under greenhouse conditions; cotton plants were grown in pots, in a DBC statistical design (five replications), evaluating the attack of whitefly on cotton varieties, with determination of productivity and fiber quality, from infestations at different phenological stages. The infestation occurred by placing cotton varieties side by side with host plants infested with adult insects from the breeding. A nonpreference test of oviposition and ninfal development was performed to determine the resistance of the varieties, with a choice. For fiber quality, caramelization test and degree of fumagine were performed. The correlation data between infestation, quality and fiber production were analyzed by multivariate analysis. The results obtained provided relevant information on the choice of variety to be cultivated and / or studies of the causes of resistance, as well as indicated the phenological stage of the crop in which the whitefly attack is more harmful.