Conditioning of fasciation by gibberellin and genotype in cotton (Gossypium hirsutum L.)

The round-leafed mutant cotton line L-501 developed fasciation of the upper stem when field grown in Central Asia. Fasciation co-segregated with the m utant gene for round leaves In-1 Fasciation developed at the flowering stag e, but removal of floral buds did not prevent fasciation. Fasciation in L-5 01 could be inhibited by the gibberellin (GA) biosynthesis inhibitor chloro choline chloride or by fusicoccin. GA, application in the field induced fas ciation in the mutant's parental line L-463, which has five-lobed leaves an d does not normally develop fasciation, Fasciation did not develop in eithe r line, even after GA, treatment, in UK glasshouse conditions.