INFLUENCE OF ULTRAVIOLET LIGHT PROTECTANTS ON THE PERSISTENCE OF THE ENTOMOPATHOGENIC FUNGUS BEAUVERIA BASSIANA

Abstract

Influence of nine UV protectants on the persistence of the entomopathogenic fungus B. bassiana (Bb 111) was evaluated in the laboratory. Among the UV protectants screened with the local B. bassiana (Bb 111) isolate, skimmed milk, yeast extract, starch, molasses and tinopal were found to be promising and offered good conidial protection with more than 70 per cent germination even after 60 minutes of UV exposure. Other UV protectants viz., folic acid (66.19%) and sucrose (61.91%) offered moderate protection of B. bassiana (Bb 111) conidia. Skimmed milk at 2 and 5 per cent concentration consistently recorded higher germination of 85.71 and 89.29 per cent respectively at 60 minutes of exposure. Upon 90 minutes of UV exposure, in B. bassiana (Bb 111) alone, the spore viability was drastically reduced to 27.38 per cent, whereas skimmed milk and starch at 5 per cent offered 71.43 and 53.85 per cent conidial germination respectively