Efeitos de espécies vegetais no controle de alphitobius diaperinus ( panzer, 1797) ( coleoptera : tenebrionidae) em sementes de sementes de amendoim ( arachis hypogaea L.)

Abstract

The utilization of plant powders has been studied as alternative method to pesticides, mainly aiming safe products to environment and human beings. Its use has been enphasized by easy obtantion, application e minor risk of the environmental contamimation. This study aimed to study the effects of bio-insecticides plant in the control of Alphitobius diaperinus. To evaluate the efficiency and repellency effects, studies were carried out at the Entomology Laboratory of the Embrapa Cotton. Peanut seeds cultivar BR1 were treated with plant powders at 10% concentration of Anadenanthera. macrocarpa Benth (Angico), Tabebuia caraíba Bur (Craibieira), Cymbopogon ciitratus Stapf (Capim Santo), Azadirachta indica A. Juss (Nim), Caesalpinia pyramidalis Tul. (Catingueira), Chenopodium ambrosioides L. (Mastruz) and C. quercifolius Pax e Hoffm (Faveleira). Seeds were mixed by manual shaking the plant powders in plastic recipients. Afterwards, 40 adult insects not sexed were introduced in each plastic recipient. Efficiency of control was calculated by Abbott 's method (1925) at 15 days and Sun - Shepard's method (Püntener, 1981) at 30 and 45 from the start of the bioassay. Data were submitted to Analysis of Variance (P≤0.05) and the means compared by Tukey test (P≤0,05). The repellence was evaluated in circular arena, with six recipients distributed equidistantly from each other and alternately with treated seeds and untreated. In the center of the arena 30 adult insects were released and, after 24 hours, the number of insects was recorded in each plastic recipient. To evaluate the effect of the plant powders on A. diaperinus the Index of Repellency (IR) (LIN et al., 1990) was used. According to the results, Chenopodium ambrosioides presented high potential to be used as a tool in the integrated management of Alphitobius diaperinus in grains storage. All the plant powders were considered repellents, with highlight for Chenopodium ambrosioides and Cymbopogon ciitratus.