Biological control of cashew powdery mildew using Ampelomyces quisqualis Ces

Abstract

The evaluation of the possibility of exploiting Ampelomyces quisqualis, mycoparasitic fungi for the biocontrol of cashew powdery mildew (Oidium anacardii) was studied. An in vitro biological control test on detached leaves of cashew was used and a detailed microscopic analysis of the interactions between mycoparasite and O. anacardii conducted. Effect of mycoparasite on disease severity and incidence was discussed. Ampelomyces quisqualis was confirmed as a mycoparasite of O. anacardii. When grown near the pathogen, A. quisqualis was seen entwining around the pathogen mycelium. It was stimulated to produce branches that grew directly to the mycelium of pathogen Ampelomyces quisqualis firm attachment on the pathogen conidia resulted in the penetration and successful growth. Some of the impregnated O. anacardii conidia were found dead. Koch’s postulates were satisfied to establish the mycoparasitism of A. quisqualis. KEY WORDS: Oidium anacardii, cashew, Ampelomyces quisqualis, biological control