Botryodiplodia Trunk Lesions in Texas Citrus. R. M. Davis, Texas A&I University Citrus Center, Weslaco 78596. C. J. Farrald, and D. Davila, Texas A&I University Citrus Center, Weslaco 78596. Plant Dis. 71:848-849. Accepted for publication 22 April 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0848.

The causal agent of a trunk disease of young citrus trees in South Texas was investigated. The disease was characterized by gray to tan lesions of the inner wood, copious gumming, and a consistent association with freeze-damaged tissue. Symptoms of the disease were reproduced with two isolates of Botryodiplodia theobromae, but 10 other isolates of the fungus were apparently avirulent. To determine the relative ability of the 12 isolates to decay citrus wood, sterilized blocks of citrus wood were inoculated, incubated for 16 wk, and weighed. One of the two virulent isolates reduced the weights of the blocks by 12.5%; all other isolates reduced their weights by about 4%.

Keyword(s): Diplodia natalensis.