VIEW ARTICLE

Ascospore Survival in Mycosphaerella musicola. R. H. Stover, Tropical Research Department, Tela Railroad Company (a subsidiary of the United Fruit Company), La Lima, Honduras; Phytopathology 61:139-141. Accepted for publication 5 August 1970. DOI: 10.1094/Phyto-61-139.

Survival of Mycosphaerella musicola ascospores in banana leaves was tested at 53, 75, 93, and 100% relative humidities continuously and at 53, 75, and 93% during the day and 100% at night. Germination was greatest with low humidities during the day and high humidities at night. This corresponded to the survival time in tissue exposed to the shade while attached to green banana leaves in the field. A majority of perithecia failed to discharge ascospores after 8 weeks regardless of storage environment except when kept at 5-7 C in a sealed container. In banana fields, survival and infectivity of ascospores are longest in shaded locations with moderate temperatures and with low daytime and high night-time humidities such as commonly occur during dry periods. Even under such conditions, ascospores do not survive in quantity beyond 8 weeks. These results indicate that ambient humidity in the field is a primary factor in the longevity of ascospores.