Effects of Crop Season, Storage Conditions, Cultivars, and Fungicide on Postharvest Mold Fungi Infecting Sorghum Grain

Abstract

<p>The frequency of fungal infection of sorghum grain samples taken from 5 storage systems (gunny bags, mud-lined baskets (MB), polypropylene bags (PB), an MB/PB mix and open storage in the corner of a room), involving 26 different varieties, hybrids or local cultivars, 2 seasons (1996 rainy and 1996/97 post-rainy) and 4 fungicide treatments (surface sterilization with 1% sodium hypochlorite plus benomyl treatment, sodium hypochlorite or benomyl alone, and an untreated control) was recorded from rural areas of India (Andhra Pradesh, Karnataka and Maharashtra) in 1997. The major fungi recorded in the samples were Alternaria alternata, Aspergillus flavus, Aspergillus niger, Bipolaris australiensis [Cochliobolus australiensis], Curvularia lunata [Cochliobolus lunatus], C. lunata var. aeria, Fusarium moniliforme [Gibberella fujikuroi], Lisea fujikuroi [Gibberella fujikuroi], Penicillium citrinum, Phoma sorghina and Rhizopus stolonifer. Full results are tabulated. Grain germination was better in samples collected after the rainy season and from grain stored in gunny bags and mud-lined baskets. Local cultivars tended to germinate better than hybrids and have lower fungal infection. Grains surface-sterilized with 1% sodium hypochlorite and treated with benomyl (0.05%) had the highest germination (81%), but sterilization did not eliminate all fungal contamination. It is suggested that grain be stored in gunny bags or jute bags to minimize damage from Fusarium spp. and that mold tolerant/resistant genotypes are grown during the rainy season.</p>