Effect of Formulated Yeast in Suppressing the Liberation of Botrytis cinerea Conidia

Abstract

Eight yeast isolates that bound directly to Botrytis cinerea germlings were assessed for the ability to suppress spore liberation of conidia from B. cinerea. After the yeast cell suspension from each isolate was mixed with cellulose and dried, the product was milled into a fine powder. This yeast-cellulose formulation was applied as a dry powder to sporulating B. cinerea colonies on kiwifruit (Actinidia deliciosa) leaf disks, where the particles from the formulation attached to conidiophores and conidia. Some of these formulations significantly suppressed the liberation of conidia from treated colonies. Suppression of conidial liberation could provide another management tool for the biological control of sporulating B. cinerea with applications during late epidemic development. Using α-cellulose prepared with Candida pulcherrima in the conditions imposed in the present study, there was an approximately 50% reduction in the number of conidia released with the treatment of the B. cinerea lesions. The suppression of disease through a reduction in the population of liberated conidia is discussed.