The Research On Heredity And Physiology Of Dongxiang Wild Rice Dormant Buds

It is helpful to study the physiological and genetic mechanism underlying Dongxiang wild rice’s dormant buds. Taking effective measures such as breeding and cultivation can ensure the grain yield and improve quality of rice. This article chooses Dongxiang wild rice and its hybrids as research objects. On the one hand, it elucidates the genetic mechanism of Dongxiang wild rice’s dormant buds’overwintering, by observing the main agronomic traits, overwintering seedlings, dormant buds. On the other hand, it elucidates the physiological mechanism of Dongxiang wild rice’s dormant buds, by analyzing POD activity and MDA content. The results are as follow:1. During the physiological developmental stages, the dormant buds were observed to be similar to the seed’s plumule. Compared with the third node, the first node and second node had more seedlings, buds and growing points. During the physiological developmental stages, there were differences between different nodes in the same plant, even the same node in different tillers or tow buds at the same node. The heritability was different between hybrids, but heritability level was high. So Dongxiang wild rice was a useful new genetic germplasm resource. And we should be careful to keep buds in the same developmental stages.2. Under low temperature stress (1-2d), POD activity and MDA content showed the activity increase in Dongxiang wild rice and its hybrids. The MDA content in root was less than leaf. The POD activity in leaf was higher than root. But the POD activity in root was more stable. It shows that the affect of cold to root was less than leaf. So I think the low level MDA content and stable POD activity maybe are the reasons why buds could overwinter.3. Genetic mechanism of overwintering character in Dongxiang wild rice was analyzed by AD genetic model. The results showed that the genetic models of overwintering character belonged to additive-dominance model, and that the dominance was low. The major effect was the additive, and the character was affected by cytoplasm. Its heritability was pretty high. It showed the overwintering character can be entailed on their hybrids steadily. Thereby, Dongxiang wild rice will be used widely in the future.