Bioatividade de compostos vegetais sobre Zabrotes subfasciatus (BOHEMAN).

Abstract

This study aimed to identify and select powder and vegetable oils with plant protection action on Phaseolus vulgaris, and its effects on the biotic potential Zabrotes subfasciatus. The survey was conducted in the Plant Clinic Department of Agriculture's Centre for Social and Human Sciences Agricultural (CCHSA) of the Federal University of Paraíba (UFPB), Campus III, Bananeiras, PB, where test conditions was with temperature 25 ± 5 ° C ; 75 ± 15% RH; 12 hour photoperiod. Initially, tests were performed with free choice to evaluate the effect of powders obtained from 57 plants and also vegetable oils coconut, castor oil and glycerin on olfactory behavior in adults. It was selected for lethality five repellent plants, among those with the best indices for repellency, for which it was evaluated the effect on the attractiveness, adult mortality and oviposition. The lethal dose LD15, LD20, LD5 and LD50 were determined by probit analysis using SAS© Institute software (Version 9.3). Fertility variance analysis was performed (average number of eggs per female / day), using the ANOVA procedure of ASSISTAT© (2013) and the average fecundity compared by testing "F" and regression. In the subsequent phase, variables were evaluated related to survival and fertility Zabrotes subfasciatus. The treatments were: Witness; Indian Clove DL5; Indian Clove LD50; LD15 dill and dill LD20. The variables response and the life and fertility table parameters were analyzed using ANOVA SISVAR procedure (2008). At the end of this study, it was found that the Caryophilus aromaticus powder (Indian clove) was the only one with lethal effect on adult Zabrotes subfasciatus, causing 100% mortality and preventing oviposition; The Anethum graveolens powder (dill) also reduced the insect oviposition. For the variables longevity, oviposition, mortality and sex ratio there was no significant effect of the treatments. However, Indian clove LD50 had the lowest percentage of emergence in the first generation, showing significant difference from the other treatments and the variable duration of the immature stage was greater the other treatments (28.66 days). The longer oviposition period occurred in the first generation, and was in treatment with dill LD20. For the parameters of the life table and Zabrotes subfasciatus fertility, the average generation time (T) in the control had the lowest average compared with the other treatments in the first generation. The net reproductive rate (Ro) and intrinsic rate population growth (rm) for Indian clove LD50 had statistical difference when compared to other vegetable powders. Regarding the behavior of population reduction by Indian clove in 30 days, the population created in protected grains had a reduced population growth 2.52 times smaller than the control.