Multiplex Selection of Antagonists for Controlling Banana Post-harvest Anthracnose

Multiplex selection strategy was investigated in this study for screening the antagonistic isolates of Colletotrichum musae and assessing their potential ability to control banana anthracnose. Out of the primarily screened 997 isolates, 280 antagonists were found out. Among these antagonists, 20 isolates with higher suppression ability were chosen for multiplex selection using three screening methods (inhibition on mycelial growth, spore germination and lesion extension). In the next screening tests, 20 antagonists showed various effects on vegetative growth and spore germination of C. musae and on lesion development. Sixteen of the antagonists could suppress the development of banana post-harvest anthracnose in varying degrees, while four of them resulted in higher disease indices of banana anthracnose compared to the control. The results indicated that it is not objective for evaluating an antagonist only by a single method. Multiplex selection strategy would be more useful for screening the antagonistic isolates with multiple mechanisms in controlling diseases.