STUDIES ON GLOEOSPORIUM MUSARUM CKE. & MASSEE CAUSING STORAGE ROTS OF JAMAICAN BANANAS I. ANTHRACNOSE AND ITS CHEMICAL CONTROL

A form of anthracnose, caused by Gheosporium musarum Cke. & Massee, is responsible for appreciable wastage of Jamaican Lacatan bananas. Symptoms are often evident on immature fruit after 8-10 days storage in refrigerated ships' holds. On green fruit, lesions are characteristically lenticular, having a slightly sunken, dark centre and an orange- yellow border: they rapidly increase in size as the fruits approach maturity. The fungus readily infects small scratches on the skin and, in inoculation experiments, resulted in the development of lenticular lesions after 8- 0 days storage at 55 degrees F. Many observations suggest that naturally occurring infections often originate at small abrasions acquired during handling of fruit. On the basis of histological findings, it is proposed to refer to lenticular lesions as 'non-latent anthracnose', thus distinguishing this form of infection from the 'latent' type described by earlier workers. In several experiments the antifungal antibiotic nystatin, applied as apost-inoculation fruit-dip at concentrations of zoo and 400 p. p. m., effected good control of wound-infection by G. musarum. Percentage control was inversely related to the incubation period between inoculation and treatment, there being little or no control with periods exceeding about 30 hr.