关键词: 毛竹, 种子活力, 人工老化, 生理生化变化

Abstract:

The seed vigor of moso bamboo (Phyllostachys edulis) and the physiological and biochemical changes involved in seed deterioration were investigated in this article.The results showed that the germination rate,germination index,and vigor index all decreased rapidly in the beginning and slowly later in response to the artifical aging. The vigor index of seeds decreased more rapidly than the germination rate and germination index. The vigor index of moso bamboo seeds decreased by 70% after 6 days of artificially accelerated aging, and lost almost all after 12 days of artificially accelerated aging. With the seed vigor declining, the physiological and biochemical changes were observed. The relative electric conductivity of the seed leachate, soluble sugar content, and MDA content of the seed extract were increased, while the soluble protein content, and the activity of antioxidant enzymes SOD,CAT and POD were declined. The content of GA₃ and IAA, and GA₃/ABA ratio were decreased. The correlation analysis indicated there was a very significant positive correlation between the activity of antioxidant enzymes SOD and CAT, the soluble protein content, the content of GA₃ and IAA, GA₃/ABA ratio and the seed vigor, while there was a very significant negative correlation between the relative electrical conductivity, MDA content, ABA content and the seed vigor. It was suggested that the injury to the membrance integrality caused by peroxidation of membrane lipids was one the main mechanisms to cause or accelerate seed deterioration in the artificial aging. The balance loss of endogenous hormones also played an important role in influencing seed germination and speeding up the seed deterioration.

Key words: Phyllostachys edulis, seed vigor, artificial aging, physiological and biological changes