Studies on Seed Dormancy and Dormancy Breaking

Seed dormancy is regarded as the phenomenon in which the vigorous seeds are unable to germinate under the suitable germination condition.There are basically two categories of dormancy,the one of which is caused by seed coat,the other of which is caused by embryo.In fact,dormancy is very complicated because of its complex traits:the first one is regulated and controlled by complex genetic characters;the second one is influenced by environmental factors,such as light and temperature,during seed development on the mother plants,during seed storage,and during germination.According to the complicated causes of seed dormancy,various methods can be used for breaking dormancy.Mainly there are physical,chemical and comprehensive methods.However,seed dormancy can be broken by a variety of physical treatment such as mechanical,temperature,stratification,hot and dry storage,radiation,ultrasonic waves,magnetic field etc.And chemical treatment such as hormones,organic and inorganic chemicals,and using the comprehensive methods to break dormancy is more effective than a mono-treatment for those seeds that induced dormancy by complicated factors.