Plant extracts as potential control agents of Black Sigatoka in banana

Aqueous extracts of Cinnamomum zeylanicum, Capsicum annuum and Azadirachta indica were tested for efficacy for management of Pseudocercospora fijiensis in banana (Musa spp.) when applied as foliar sprays. Extracts of C. annuum and A.indica demonstrated fungicidal effects in vitro, without showing phytotoxic effects. The two extracts protected tissue culture banana plantlets of cultivar Musakala to a similar degree as the traditional fungicide difenoconazole. Extracts of A. indica and C. annuum (0.3 g/ml) reduced Black Sigatoka severity by 69.3% and 65.6%, respectively, and were thus comparable to the fungicide difenoconazole (72.7%). Soil drenching of the extracts did not significantly reduce Black Sigatoka severity. In planta effects of the extracts mainly consisted of delayed symptom appearance and reduced lesion number. Symptom development was dependent on extract concentration and days between extract application and inoculation. Effect of the tested extracts on height of plants and new leaves was not significant. Collectively, our data suggest that A. indica and C. annuum have interesting and unique properties as plant protection agents against Pseudocercospora fijiensis, but further research is needed to investigate their efficacy