Leaf scald disease

Rats are a serious pest in cane fields in several countries, particularly in Australia, Taiwan, British Guiana, Puerto Rico, and Mexico. They are a factor in dissemination of leaf scald disease in British Guiana. Trapping and warfarin [3-(alpha-acetonylbenzyl)-4-hydroxycoumarin] baiting are practiced. Warfarin is used by an estimated 80% of the cane growers in Puerto Rico. Mexico uses 1000 pounds of warfarin annually. British Guiana uses 12,000 pounds of 1% warfarin annually and anticipates this demand will continue indefinitely. Taiwan reports use of 6565 pounds of 0.5% warfarin on 13,000 acres with good results and expects to continue its use. 

In the presence of Mo deficiency, low nitrate reductase activity results in high accumulations of NO," in plants, with many physiological implications. Disorders such as scald disease of beans (Phaseolus vulgaris) (Wilson, 1949) and leaf burn/scorch of clementine (Citrus sinensis) trees (Triboi, 1978 Cassin et al., 1982) have been related to nitrate accumulation in the presence of a short supply of Mo. Premature sprouting of... 

Fruit with large, Eaded or gray-white, sunken patches. Cause Sun.scald. Green or ripe fruit can be affected. Control leaf diseases to prevent defoliation so fruit will be shaded and protected from direct sun. 

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