THE PRO GENE CAUSES AN ENHANCED CELL EXPANSION RESPONSE TO FUSICOCCININ TOMATO

The response to fusicoccin (FC) of the elongated tomato mutant procera was tested. Hypocotyl sections from etiolated procera seedlings respo nded to a range of FC concentrations similar to that of normal section s, but at a given FC concentration the mutant sections exhibited about 40% greater elongation than normal. The initial rates of elongation i n FC were similar for normal and procera sections, but elongation cont inued at a high rate for a longer period in the mutant. Measurements o f outer cortical cells demonstrated that the enhanced elongation of th e procera hypocotyl sections was due to enhanced cell expansion.