The effect of some aldonolactones on the IAA‐induced growth of lupin hypocotyl segments

Lactones of monosaccharide aldonic acids are specific inhibitors of polysaccharides in vitro . The effect of some of these lactones on the growth of lupin hypocotyl segments was measured in the presence or absence of 30 µM indolyl‐3‐acetic acid (IAA). No short‐term effect on IAA‐induced growth was found for gluconolactone or γ‐L‐galactonolactone bat γ‐D‐galactonolactone gave a shortterm stimulation, not an inhibition, of the growth of segments already in IAA. Implications of these findings for the mechanism of cell expansion are discussed.