Detection of seed germination inhibitors in dormant seeds of angelica glauca edgew. and polygonatum verticillatum(L.) all. from Kinnaur (Himachal Pradesh)

Although seed dormancy is advantageous in an ecological context, it hampers the plant regeneration. Seed dormancy could inter alia be ascribed to an array of germination inhibiting substances present in the embryo or other seed parts. In the present study, the presence of germination inhibitors in the dormant seeds of two medicinally important plant species namely, Angelica glauca and Polygonatum verticillatum from Kinnaur (Himachal Pradesh) has been determined by monitoring the effect of leachate and extract of dormant seeds on germination of seeds of a phytometer species namely, Brassica juncea. Due to the treatment with the extract of freshly harvested, 1, 2 and 3 year stored seeds of A. glauca, a 39, 46, 32 and 25% inhibition of B. juncea seed germination was evident. Similar observations were obtained with seed leachate with some quantitative differences. A comparable suppression of B. juncea seed germination was also observed due to the extract/leachate of P. verticillatum seeds. The findings reveal the presence of inhibitors involved in seed dormancy regulation of concerned species. Interestingly, there appeared a loss of inhibitors with storage of seeds as revealed by the reduction in the degree of inhibition of B. juncea seeds