Efficiency of chemical control of Bemisia tabaci biotype "B" (Hemiptera: Aleyrodidae) in cucumber crop

Abstract

The research was carried out at the experimental field of Agronomy / UFG School in Goiânia - GO to evaluate insecticides in the control whitefly (Bemisia tabaci biotype "B") in cucumber crop. The experimental design was a randomized blocks with six treatments and four replications. Each inseticide application was made by using interval of seven days. The treatments were: control, diafenthiuron 500 SC at doses of 40, 60, 80 and 100 ml p.c./100 L of water and pyriproxyfen EC 100 at a dose of 75 ml p.c./100 L of water. The crop evaluations were realized at 7, 14, 21 and 28 days after germination. The live nymphs in 25 leaves / plot were ramdomized and evaluated in upper third plant leaves with the aid of a magnifying glass of 20 fold increase pocket. Control nymphs of B. tabaciraça biotype "B" after three sequential inseticide applications with seven day intervals is considered an acceptable efficiency obtained by using doses of 80 and p.c.100 ml of diafentiuron 500 SC Polo/ 100 L of water and 75 ml p.c. of piriproxifen Cordial 100 EC/100 L of water.