Viability of Penicillium bilaji and Colletotrichum gloeosporioides conidia from liquid cultures

Abstract

The effect of water activity on Penicillium bilaji Chalabuda and Colletotrichum gloeosporioides f.sp. malvae conidia at 20 °C was examined. The optimal relative humidity for storage at 20 °C was found to be 12–34% for C. gloeosporioides spores and 100% for P. bilaji spores. Retention of viability by C. gloeosporioides spores was improved by drying the spores from a 20% sucrose solution. The data demonstrate the conditions required for adequate shelf stability for commercial, biological products for agricultural application, based on these two organisms. Key words: Penicillium bilaji, Collectotrichum gloeosporioides, water activity, germinability.