ABSTRACT
The objective of this work was to evaluate the efficiency of microbial agents in the control of Alabama argillaceain the cotton crop. The experiment was installed in Cassilândia County, Mato Grosso do Sul State, Brazil, in a crop of BRS 200 Brown. The treatments were: 1 – control; 2 – Beauveria bassiana (2 kg/ha); 3 – Metharizium anisopliae (2 kg/ha); 4 – Bacillus thuringiensis (0.5 L/ha); 5 – complete treatment ( B. bassiana (2 kg/ha) + M. anisopliae (2 kg/ha) + B. thuringiensis (0.5 L/ha). The viability of B. bassiana and M. anisopliae was 85%. The number of live caterpillars found in 20 plants per plot was counted before the application (prior recording) and the observations were carried out at 3, 6 and 10 D.A.A (days after the application). In the evaluation made at 3 D.A.A the smallest efficiencies were observed for the agents. However, in the evaluation made at 10 d.a.a, the treatments B. bassiana, M. anisopliae, complete treatment and B. thuringiensis were efficient, with efficiencies of 77, 68, 84 and 86% respectively.
KEY WORDS
Cotton; microbial control; cotton leafworm