FUNGO ENTOMOPATOGÊNICO Cordyceps fumosorosea NO CONTROLE DE Bemisia tabaci EM FEIJOEIRO COMUM

Abstract

Common bean is one of the main crops in Brazil. The whitefly (Bemisia tabaci) is considered one of the main pests in this culture and is also the vector of the golden mosaic. Chemical control is still the most used method to control B. tabaci, however, biological control is gaining more space. The objective of this study was to evaluate the control of B. tabaci in common bean by applying conidia of the Cordyceps fumosoroseae (BioIsa®) isolated and associated with Acetamiprid + Pyriproxyfen (Trivor®). The experiments were carried out in the experimental field of the Instituto Federal Goiano of Urutaí. Four treatments (BioIsa ®; Trivor ®; BioIsa ® + Trivor ® and control) were used in two applications in the common bean stages V2 and V2 + 10 days. The experiments were carried out in randomized blocks in a split-plot scheme. The number of eggs, nymphs and adults of B. tabaci was recorded at 0, 4 and 8 days after each application and the incidence of golden mosaic at 0, 4, 8, 12, 19, 26, e 33 days after the first application. Data analyzes were performed using the Poisson and Binomial generalized linear model, respectively, for insect count and disease incidence data. The chemical and biological association did not show synergistic effects in the control of B. tabaci. The BioIsa® and Trivor® products were effective in controlling nymphs, however, these products showed low efficiency to reduce the number of eggs and adults. These results may be associated with a lack of mobility at this stage compared to adults, which favors fungus colonization. The incidence of golden mosaic was greater than 90% in all evaluated plots, therefore, the reduction of the number of insects in the field was unable to reduce the number of infected plants.