Controle alternativo de Plutella xylostella em couve

Abstract

Plutella xylostella is the main insect pest of cruciferous crops, causing damage to plantations worldwide. It exhibits high reproductive and adaptive capacity, leading to populations that are resistant to virtually all available insecticide mechanisms of action on the market. In this context, the objective of this study was to evaluate the insecticidal properties of the fungi Metarhizium anisopliae and Beauveria bassiana, as well as potassium silicate and a commercially available product based on azadirachtin, for the control of P. xylostella. The experiment was conducted at the Entomology Laboratory of UTFPR-Campus Pato Branco, following a randomized complete block design with five treatments and four replications. The ability of each treatment to reduce herbivory rates, control larvae, and decrease pupal viability was assessed. The following doses were used for each treatment: 50 g/ha of the commercially available product based on M. anisopliae, 5 kg/ha of the commercially available product based on B. bassiana, 1 L/ha of potassium silicate, and 1.5 L/ha of the commercially available product based on azadirachtin. The control treatment was conducted with distilled water. The most effective treatment was the use of the commercially available product based on azadirachtin, which achieved 100% control of larvae and reduced herbivory. The treatments with M. anisopliae and B. bassiana were also capable of controlling larvae and reducing pupal viability over time. On the other hand, the treatment with potassium silicate did not yield the expected results in pest control, exhibiting efficacy only in controlling larvae. Therefore, the use of azadirachtin-based products, M. anisopliae, and B. bassiana demonstrated promise for the effective long-term control of P. xylostella.