
%0 Journal Article
%A Kato-Noguchi, H 
%A Sumitomo, M 
%T Effect of Uv Radiation on Endogenous Inhibitors of Growth in the Hypocotyl of <I>Phaseolus vulgaris</I>
%J Functional Plant Biology
%D 1994/04/01
%V 21
%N 2
%P 235-241
%K 
%R https://doi.org/10.1071/PP9940235
%U https://www.publish.csiro.au/paper/PP9940235 
%X In order to correlate the role of endogenous inhibitors of growth of bean plants with the inhibition of such growth by UV radiation, a search for specific growth inhibitors was undertaken using the neutral and acidic fractions of acetone extracts from the hypocotyls of UV-irradiated bean seedlings (Phaseolus vulgaris L. cv. Morocco). Tho neutral and two acidic inhibitors were isolated and they were named N-1 and N-2 (neutral inhibitors) and A-1 and A-2 (acidic inhibitors), respectively, on the basis of the order of their elution from a silica-gel column. Variations in the activity of the inhibitors in hypocotyls of two cultivars (cvv. Morocco and Kentucky 101) after the onset of UV radiation were determined by use of a bean bioassay, and results were compared with those of UV-induced inhibition of growth. The growth of hypocotyls of the two cultivars decreased rapidly. However, the more noticeable change was a marked decrease in the growth of the hypocotyls of cv. Morocco. On the other side, the difference in the activity of N-1 between the two cultivars was particularly great, and the changes with time in levels of N-1 in hypocotyls of each cultivar matched the time course of the UV-induced inhibition of growth of hypocotyls of the same cultivar. No such correlation was found with N-2, A-1 and A-2. These results suggest that the activity of N-1 may serve to distinguish the growth habit of the two cultivars to UV radiation. 
