Assessment of insecticidal activity of red pigment produced by the fungus Beauveria bassiana

Abstract

Insecticidal activity of the red pigment produced by a strain of the fungus Beauveria bassiana that was locally isolated from infected whitefly, Bemisia tabaci (Genn.) was assessed. The pigment is produced extracellularly and is watersoluble. This makes it easy and simple to be recovered from fermentation broth and used in pathogenicity experiments. When applied alone to B. tabaci nymphs, mortality percentages of 18% was recorded. For nymphs treated with B. bassiana spore suspension, mortality was 60%. The best results were obtained when red pigment was combined with fungal spores with the mortality percentage being increased to up to 92%. The highest virulence against adults emerged later on from the surviving larvae of B. tabaci and the longest days to pupation were also recorded with this treatment. © 2011 Taylor & Francis.