Resistance of cassava genotypes to Bemisia tuberculata

Abstract

Bemisia tuberculata Bondar, 1923 (Hemiptera: Aleyrodidae) is one of the most important pest of cassava Manihot esculenta Crantz in Brazil. However, there is a lack of information about the bioecology and control to this species. An alternative for managing whitefly populations is to develop genetically resistant varieties. To improve the understanding about the bioecology and to find new sources of resistance in cassava were evaluated biological and demographics parameters of B. tuberculata on six genotypes (MEcu 72, Santa Helena, IAC-Caapora, IPR-UniAo, Caiua, and Baianinha) under controlled conditions (25 +/- 2 degrees C, 12L/D). The average of survival rate, longevity and oviposition of B. tuberculata fed on MEcu 72 were the lowest. The nymphs of B. tuberculata were difficulty in development and feed on this genotype. The fecundity life table showed a significant impact of the MEcu 72 on the potential growth of B. tuberculata. When fed on Santa Helena, the females were a similar size to those fed on genotypes that are more susceptible, however, they were the lowest oviposition rates. Considering the parameters evaluated, the results from this study revealed important levels of resistance to the B. tuberculata on the genotypes MEcu 72 and Santa Helena.