Epidemiology of powdery mildew on mango blossoms.
Schoeman M. H., Manicom B. Q., Wingfield M. J.
Author Affiliation: Institute for Tropical and Subtropical Crops, Private Bag X11208, Nelspruit 1200, South Africa.
Plant Disease 79 : 524-528
Abstract : Conidia of Oidium mangiferae, causal agent of powdery mildew on mango, were trapped in a mango orchard at Nelspruit, South Africa, during the periods of flowering and fruit set from 1989-91. Hourly aerial conidial concn were correlated positively with hourly temp. and negatively with hourly RH, vapour pressure deficit and leaf wetness. The number of trapped airborne conidia of O. mangiferae was characterized by a distinct diurnal periodicity. The greatest number of conidia were trapped between 1100 and l600 h. The first powdery mildew symptoms appeared at approx. the same time each year. Inflorescences were susceptible during the period beginning when the main axes changed colour and ending at fruit set.