Seed dormancy in Himalayan maple (Acer caesium) I: Effect of stratification and phyto-hormones

Author： Phartyal S.S. Thapliyal R.C. Nayal J.S. Joshi G.

Publisher： International Seed Testing Association

ISSN： 1819-5717

Source： Seed Science and Technology, Vol.31, Iss.1, 2003-04, pp. : 1-11

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Investigations on the dormancy, role of covering structures, stratification requirement, optimum temperatures and the effect of exogenous application of plant growth hormones on germination of two lots of A. caesium seeds were undertaken both under the laboratory and in field conditions. The prolonged cold stratification at 5°C for about 24-28 weeks was the only effective treatment to overcome the dormancy of seeds. Cold moist stratification with 100 ppm thiourea and a combination of 100 ppm GA₃+cytokinin with pricked pericarp and testa of samara appeared to result in the best germination (50%). The Mandal seed lot required shorter stratification period as compared to the Mussoorie seed lot, indicating source variation in the degree of dormancy. The best incubation temperature for maximum germination of stratified seeds ranged from 5-10°C but the latter was the most effective in terms of germination percentage as well as the rate of germination. Under conditions of natural stratification autumn-sown seeds responded to germination readily well within four months with higher germination as compared to the spring-sown seeds, which took about 12 months to germinate. The overall results indicated deep physiological dormancy of seed in A. caesium. This was further confirmed by the exogenous application of growth regulators (GA₃) on the non-stratified embryo and testa pricked seed which stimulated the germination and growth of embryo/seed and substituted the requirement of cold stratification to some extent but the growing embryo did not show potential to develop into normal seedlings in contrast to the stratified seed.