Factors affecting bacterial black spot of mangoes caused by Xanthomonas campestris pv. mangiferaeindicae.
Manicom B. Q.
Author Affiliation: Citrus Subtrop. Fruit Res. Inst., Nelspruit, South Africa.
Annals of Applied Biology 109 : 129-135
Abstract : The bacterium proved to be essentially a wound pathogen of leaves under greenhouse conditions, with max. infection at a temp. regime of 22/26°C (night/day). There were significant differences among cultivars, cv. Sensation being less, and cv. Haden more susceptible than Zill and Kent, which agrees with field observations of fruit infection. The organism is a phylloplane resident throughout the year in the field and inoculum levels in the tree canopy affect ultimate fruit infection. The major weather factor affecting fruit infection was rainfall which was significantly correlated with infection levels after allowing for an approx. 2 wk latent period. Other significant correlations were with a wind/rain index and a storm index. The correlation of disease with the duration of free water was non-significant.