THE INFLUENCE OF LIGHT AND POTASSIUM NITRATE ON THE DORMANCY AND GERMINATION OF AVENAFATUA L. (WILDOAT) SEED AND ITS ECOLOGICAL SIGNIFICANCE

Abstract

It has been suggested that applications of nitrogen‐containing fertilizers can stimulate the germination of dormant Avena fatua L. seed in the field and may be used to reduce numbers of seeds in the soil. However, it is not clear whether a subsequent cultivation imposing a light treatment on a proportion of the buried seeds is also necessary. To study this question potassium nitrate (KNO3) was applied to dormant seed of A. fatua in darkness and in light under controlled laboratory conditions. Potassium nitrate had very little effect on germination in darkness but concentrations of 2 × 10−4, 2 × 10−3 and 2 × 10−2 M stimulated germination in the light. The degree of stimulation by light was related to the proportion of phytochrome that was maintained as Pfr, the physiologically active form. In the presence of 2 × 10−1 M KNO3 no germination occurred either in light or in darkness. Copyright © 1984, Wiley Blackwell. All rights reserved