塔里木荒漠豆科植物种子休眠原因与破除方法研究

Dormancy Mechanism and Breaking Methods of Three Desert Legume Plant Seed

以塔里木荒漠区3种豆科植物种子为材料,采用不同破除豆科植物种子休眠的方法,研究不同方法对种子休眠的解除效应,探讨种子休眠原因并寻求打破种子休眠的最佳途径。结果表明:3种荒漠豆科植物种子属物理性种壳休眠,种皮障碍是限制种子萌发的主要因素。热水、赤霉素、过氧化氢、乙醇、氢氧化钠等化学处理均可破除种子休眠,但种子发芽率与清水对照无显著差异,处理效果不佳。机械破损种皮和浓硫酸处理均能有效打破种子休眠、显著提高发芽率。种子发芽率随硫酸浓度增加与处理时间延长而明显提高,80%以上浓度的H_2SO_4处理效果较好,其中以80%H_2SO_4处理90min,90%H_2SO_4处理50min,98%H_2SO_4处理30min为最佳,种子发芽率超过98%。因此,利用小型机械和浓硫酸处理是破除荒漠豆科植物种皮休眠障碍的最佳方法,研究结果可为荒漠区人工种植与荒漠植被恢复提供科学依据。

In order to clarify the dormancy causes and find better methods for breaking seed dormancy to cultivate and restore desert vegetation,the efficacy of different tretaments on seed germination and dormancybreaking of three legume plants were studied.We used filter paper for germination bed,clean water for ck,and differnt physical and chemical methods treated Glycyrrhiza inflata,Sophora alopecuroides,Swainsonia salsulaseeds to observe the seed germination characteristics.The result showed seed dormancy cause of three desert leguminous plant belonged to the physical shell dormancy,both imperameability and mechnical barrier of seed coat were the key factors limiting seed germination.Those chemical treatments of hot-water,GA3,hydrogen peroxide solution,ethanol and NaOH all breaked seed dormancy,but seed germination rate of those methods were not significantly difference with water treatment（ck）and treatment effect were poor.The treatments of sulfuric acid and cutting seed coats breaked effectively the seed dormancy and improved significantly germination rate.Seed germination rate improved obviously with increase of sulphuric acid concentration and treatment time,the treatment effect was good with more than 80% H2SO4,especially the best treatment time of 80%,90%,98% H2SO4 were 90 min,50min,30 min,and seed germination rate were more than 98%respecially.In summary,the best methods for breaking dormancy were treating with sulfuric acid and small machinery to break shell,this provide scientific basis for culture and vegetation restore in extremely arid regin.