Fusicoccin as an inducer of mango malformation.
Usha K., Bhupinder Singh
Author Affiliation: Division of Fruits and Horticultural Technology, Indian Agricultural Research Institute, New Delhi 110 012, India.
Journal of Plant Biology 27 : 313-315
Abstract : In a field experiment conducted in New Delhi, India [date not given], the exogenous application of ABA [abscisic acid], gibberellic acid, IAA, and kinetin (50, 100, and 150 ppm) did not induce symptoms of malformation. On the other hand, all healthy buds and developing panicles treated with fusicoccin (a diterpenoid glycoside from Fusicoccum amygdali [Phomopsis amygdali]) developed into malformed inflorescence. Fusicoccin at 10-4M induced morphological distortions (highly shortened axes of panicles, multiple branches, and large male flowers) and inhibited fruit formation. Fusicoccin at 10-7M inhibited panicle elongation and caused morphological distortions to a lesser extent. Endogenous levels of fusicoccin were high in malformed than normal buds and panicles. The endogenous fusicoccin content was higher in completely malformed than in partially malformed buds and panicles. Fusicoccin may be interfering with the metabolic processes during the early stages of bud development which results in abnormal inflorescence growth.