Genetic variability of the fungus Beauveria spp. isolates and virulence to the lesser mealworm Alphitobius diaperinus Panzer (Coleoptera: Tenebrionidae)

Abstract

The genetic variability of 13 Beauveria spp. isolates was assessed by RAPD technique and verified the relationship between the molecular profiles generated and geographical location of isolates, the original host and pathogenicity to the lesser-mealworm Alphitobius diaperinus. Pathogenicity bioassays were carried with larvae and adult insects at fungal concentration of 10⁹ conidia / mL, during a ten-day period. With RAPD technique, seven of 50 tested primers showed consistent banding patterns. Two groups with a similarity level above 60% were observed in the analysis profiles and one of them formed only by isolates from the lesser mealworm, with 72% of similarity. Was found relationship between the origin host of the isolates and the molecular profile, generated in the analysis. There was no relationship between the molecular profiles and the geographical location or pathogenicity to the insect. The results showed that even the isolates collected in near areas may have highly variability.