Insects and mycobiota in Phaseolus vulgaris L. grains sold in retail stores

Abstract

In Brazil beans are an important protein source and the great variety of Phaseolus and Vigna beans grains are sold in retail markets. The objective of this study was to isolate fungi from insects and Phaseolus vulgaris (var. Pinto) from 15 samples of different retail stores in São Paulo. The samples were placed in Petri dishes containing culture medium of potato-dextrose-agar and incubated at 25°C for 7 days. Fungi were identified in several insects: Callosobruchus maculatus (yeasts - 50%), Sitophilus spp. (Chaetomium spp. – 3.1%; Rhizopus stolonifer- 3.1%; Non Sporulating Fungi (NSF) – 12.5% and Eurotium chevalieri - 9.4%, Acanthoscelides obtectus (Penicillium spp. – 18.5% and yeasts – 18.5%) and Zabrotes subfasciatus (Alternaria alternata – 13.6 % and Penicillium spp. – 41 %). No fungi were observed in the parasitoid Dinarmus basalis. In grain samples, the following fungi were found: Penicillium spp. (6%), E. chevalieri (5%), R. stolonifer (0.3%), Aspergillus flavus (3 %), NSF (8 %), Yeasts (2.6%), Phoma spp. (1.6%) and Alternaria alternata (3.6%).