Physiological studies on dormancy in seeds of groundnut (Arachis hypogaea L.). III. Changes in auxin and growth inhibitor contents during development of the seeds of a dormant and a non-dormant cultivar

Abstract

Growth substances in developing seeds of dormant and non-dormant cultivars of groundnut were chromatographically separated, and their content at various RF values estimated by the rice coleoptile bioassay technique. Growth promotors increased from 20 to 30 days in the acidic and neutral fractions of the dormant and non-dormant seeds. From 30 days onwards, growth promotors decreased while inhibitors accumulated, but their relative proportions varied in the two types of seeds. In mature non-dormant seeds, the content of growth promotors in the acidic fraction was higher than that of inhibitors; in dormant seeds it was lower. In the neutral fraction the content of inhibitors was higher than that of promotors in seeds of both types. The balance of growth-promoting and inhibiting substances in relation to seed development and dormancy is discussed, and it is concluded that the acidic inhibitors are responsible for dormancy in groundnut seeds.