First evaluation of Beauveria bassiana against the Gyropsylla spegazziniana Lizer & Trelles (Hemiptera: Psilidae) on Paraguay tea (Ilex paraguariensis St. Hil.) leaves

ALVES, LUIS FRANCISCO; FANTI, ANDRÉ LUIS; FORMENTINI, MARINA ANDRESA; BARZOTTO, IONETE; SCHAPOVALOFF, MARIA ELENA

Trabzon

Congreso; Society for Invertebrate Pathology; 2010

Society for Invertebrate Pathology

Gyropsylla spegazziniana (G.s.) is one of the most important pests of Paraguay tea crops in all South America (Brazil, Argentina and Paraguay). Natural enemies have been registered on G. spegazziniana, including entomopathogen fungi Zoophthora radicans. Here, we report the first evaluation of Beauveria bassiana pathogenicity over this pest on laboratory. Branches from Paraguay tea plants with G.s. galls were maintained in glass Erlenmeyer with water in organza cloth cages. Each treatment consisted of Paraguay tea branches infested with 15 to 30 recent emerged nymphs/leaf (3 replications/treatment). The fungus suspension (1 × 109 conidia/mL) was sprayed on the leaves that were transferred to cages (26 ± 1 °C, 70 ± 10% RH and 14 h photophase). Daily evaluation showed after five days, high level of insecticidal activity. The pathogenicity was confirmed by visual observation of fungus sporulation on insect cadavers. The total mortality ranged 25 to 65% and the higher confirmed mortality was 35% due to Unioeste 52 strain (obtained from the adults of the lesser mealworm, Alphitobius diaperinus). There is potential of the fungus to control this pest, although complementary studies should be realized.