食用蒲公英种子萌发对PEG-6000模拟干旱胁迫的响应  

Seed Germination of Edible Taraxacum mongolicum Hand.-Mazz.Under Drought Stress Simulated by PEG

作　　者：赵淑文[1] 贺晓[1] 胡云[1] 黄修梅[1] 李明[1] 

机构地区：[1]内蒙古农业大学,呼和浩特010019

出　　处：《种子》2017年第3期12-15,共4页Seed

基　　金：科技部国家科技基础条件平台项目(2005DKA 21403-JK);内蒙古农业大学基金项目

摘　　要：采用浓度分别为0%、5%、10%、15%、20%和25%的PEG-6000溶液模拟干旱条件,测定蒲公英种子在不同干旱胁迫条件下的日相对萌发率、发芽势、发芽指数、活力指数及上下胚轴长度等指标,研究了蒲公英种子萌发及幼苗生长对PEG-6000模拟干旱胁迫的响应,探讨了经20%、25%PEG-6000浸种预处理后种子的萌发恢复能力。结果表明:5%PEG-6000胁迫下提前了萌发高峰、提高了发芽率,促进了种子的萌发;10%PEG-6000胁迫显著降低了种子发芽势,但未对其发芽率产生显著影响;高度水分胁迫(15%PEG-6000浓度)显著抑制了蒲公英种子的萌发,并延长其萌发时间,但是,其种子萌发率仍是对照的73.35%,说明蒲公英具有很强的抗旱性。当重度胁迫时(20%、25%PEG-6000浓度)蒲公英种子未见萌发,解除胁迫后遇充足水分,蒲公英种子即立刻快速整齐的萌发,表现为蒲公英种子对较强干旱环境的适应性,也是野生植物的生存策略之一。0%,5%,10%,15%,20% and 25% PEG-6000 solutions were used to simulate drought stress conditions for the germination of Taraxacum mongolicum Hand.-Mazz..Daily relative germination rate,germination percentage,germination potential,germination index and vigor index under each water stress were recorded.The effects of drought stress through PEG treatment on seed germination,and the recovery germination ability by 20%,25% PEG solutions soaking pretreatment were studied in a series of laboratory tests.The results showed that the mild water stress（5% PEG concentration）compared with the control group made the germination peak ahead,improved the seed germination rate,significantly promoted the seed germination.The moderate water stress（10% PEG concentration）significantly reduced the germination potential,but had no significant effects on the germination percentage.The height water stress（15% PEG concentration）significantly inhibited the seed germination,prolonged the seed germination time,but the germination percentage was 73.35% of the control.so,T.mongolicum Hand.-Mazz.hadstrong drought resistance.When the PEG concentration was 20%or 25%,the seeds of A.Ramosum could not germinate.When seeds had enough moisture after stress relief,they could germinate immediately,quickly and orderly.This is a kind of T.mongolicum Hand.-Mazz.seeds have strong drought adaptation in adverse circumstances,is also one of the survival strategies of wild plants.

关 键 词：蒲公英 PEG-6000胁迫 种子萌发 恢复萌发 幼苗生长 

分 类 号：S647[农业科学—蔬菜学] Q945[农业科学—园艺学]