Controle e perdas provocadas por mahanarva fimbriolata (Stal) (Hemiptera: Cercopidae) em cana-de-açúcar

Abstract

This work was developed with objective of evaluating the damages and the control of the sugarcane root froghopper, Mahanarva fimbriolata. The field assay was carried out at the farms of the Industry Jalles Machado S.A. in Goianésia, Goiás State (15o 18’ 45” S; 49o 03’ 45” W), at variety RB845257, 2nd cut. The experimental randomized blocks design was employed at three places. The treatments were: thiamethoxam 250WG, 100, 150, 200 and 250 g/ha of active ingredient; carbofuran 350SC, 700 g/ha a.i.; Metarhizium anisopliae 1,0 L/ha (CB-10 10 12 ), oil formulation and check. It was evaluated the sugarcane productivity and the infestation level of nymphs of the sugarcane root froghopper until 84 days after the application. The thiamethoxam insecticide presented effect at infestation up to 84 days after the application, and they did not differ amongst themselves. The residual effect of the carbofuran happened, on average, until 63 days after application. The M. anisopliae fungal did not present effect on the infestation of nymphs during the evaluation period. Thiamethoxam insecticide presented larger residual effect than other treatments in the control, and it didn't differ at the applied dosages. There was inverse correlation between levels of nymphs infestation and sugar-cane productivity.