永瓣藤(Monimopetalum chinense Rehd)为我国特有的单种属植物,国家二级稀有濒危保护树种,其种子具体眠特性.测定了永瓣藤种子千粒质量、含水量、吸水率和种子生活力等指标,分别采用层积、酸蚀和GA3处理种子,分析不同处理对种子萌发的影响.结果表明:永瓣藤种子千粒重为(4.504 8±0.055 8)g,含水率为13.18％±1.84％,吸水率为29.95％±1.58％,种子生活力为94.25％±0.017 1％,种子萌发实验的发芽率为0；层积时间对种子萌发影响不显著,最高仅为2.67％±1.53％,种子经50％ H2SO4处理20 min的发芽率为18.00％±3.46％,种子经250 mg/L GA3处理24h然后再经室内层积75d,发芽率达到72.67％±7.02％,对照仅为1.67％±1.15％,永瓣藤种子休眠首次有效破除.永辩藤种子休眠可能与种皮障碍有关,种子内可能存在活性较强的内源抑制物质是引起种子体眠的重要原因,GA3处理能有效解除其种子休眠.%Monimopetalum chinense Rehd, is the specific species in a single genus of China. It was listed as one of national proteceted plants at the second category in Chian because of its extremely low ability of regeneration in natural population. Several physiological indexes like the weight per 1 000-seed,content of moisture,the rate of water absorption and seed vigor were measured. The germination rate were determined under different treatments of stratification, sulphuric acid treatment and the combination of presoaking the seeds with GA3. The result showed that the 1 000-seed weight and average water content of the seeds were (4.504 8 ±0. 055 8)g, 13.18% ± 1. 84% ,resp. The rate of water absorption was 29. 95% ± 1.58% ,the seed vigor was 94. 25% ± 0.017 1% ,but the germination of seed was 0. Stratification time had no significant effect on germination percentage (GP) ,the highest GP was only 2. 67% ± 1. 53%. The treatment of soaking seed 20 min under 50% H2SO4,the GP was 18.00% ±3.46%. The treatment of seed soaked 24 hours under 250 mg/kg,5 000 mg/kg, 1 000 mg/kg of GA3 ,and 75 days of stratification, the GP were 72.67% ± 7.02% ,68.00% ±3.46, ? 64.00% ±5. 29% ,resp,but the GP of ck was 1. 67% ± 1. 15%. The results of this study illustrated the dormancy of M. Chinense seeds could be breaken effectively. The mechanical and permeability barrier of seed coat had a negative effect on germination to a certain extent, seed dormancy of M. Chinense was might be due to the inhibitory substances in the seed. The presoaking seed with GA3 was one of the best way to break dormancy.
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