The influence of paclobutrazol on the distribution and utilization of 14C-labelled assimilate fixed at anthesis in oil-seed rape (Brassica napus L.)

Abstract

SUMMARYUntreated and paclobutrazol-treated field-grown plants of winter oil-seed rape cv. Jet Neuf were exposed to 14CO2 at anthesis. Redistribution of labelled assimilate was followed in sequential harvests between exposure and maturity.Labelled assimilates moved progressively from the leaves into the stem and reproductive parts. At maturity 9% of 14C fixed at anthesis had been mobilized into reproductive organs. Paclobutrazol increased the proportion of 14C translocated to the uppermost branches especially the terminal raceme.It is suggested that stem reserves are valuable for yields commonly achieved in U.K. commercial practice.