摘要
[目的]探究干旱胁迫对梯牧草种子萌发和幼苗生长的影响,筛选抗旱种质.[方法]本研究以 6份野生梯牧草材料及 1份引种材料为研究对象,采用PEG模拟干旱胁迫,设置 0%、5%、10%、15%、20%5个处理梯度,测定发芽指标与生长指标,分析抗旱性指标差异,确定适宜抗旱性鉴定浓度,筛选抗旱性种质.[结果]低浓度PEG(5%)一定程度上促进梯牧草种子的根长、芽长、鲜重、活力指数,高浓度PEG(≥15%)抑制其发芽率、发芽势、发芽指数、根长、芽长、根芽比和活力指数;与芽长相比,根长对干旱胁迫更加敏感;15%PEG宜作为梯牧草抗旱性鉴定浓度;野生材料具有较好的抗旱潜力,主成分分析及隶属函数综合评价结果一致表明7份材料抗旱性由强到弱依次为MS>TM-3>TM-5>TM-6>TM-1>TM-2>TM-4.[结论]一定程度的干旱胁迫可促进梯牧草种子萌发和幼苗生长,该研究可为梯牧草抗旱性评价及新品种培育提供参考及背景材料.
Abstract
[Objective]In order to explore the effects of drought stress on seed germination and seedling growth of Phleum pratense,the drought-resistant germplasm was screened.[Method]In this study,6 wild Phleum pratense L.forage materials and 1 introduced species material were used as research objects.PEG was used to simulate drought stress,and 5 treatment gradients of 0%,5%,10%,15%and 20%were set.The germination indexes and growth indexes were determined,the differences of drought resistance indexes were analyzed,and the appropriate drought resistance identification concentration was determined and drought resistance germplasm was screened.[Result]The results showed that the low concentration of PEG(5%)could promote the root length,shoot length,seedling fresh weight and vigour index,while the high concentration of PEG(≥15%)would inhibit the germination rate,germination potential,germination index,root length,shoot length,root-shoot ratio and vigour index.And the root length of Phleum pratense L.was more sensitive than shoot length for drought stress.15%PEG was suitable for identifying drought resistance.Wild materials had better drought resistance potential.The results of principal compo-nent analysis and membership function comprehensive evaluation showed that the drought resistance of the seven ma-terials was MS>TM-3>TM-5>TM-6>TM-1>TM-2>TM-4 from strong to weak.[Conclusion]The research revealed that a certain degree of drought stress could promote seed germination and seed-ling growth of Phleum pratense,and could provide some reference for the screening of drought-tolerant germplasm and the breeding of new drought-tolerant varieties of Phleum pratense.
基金项目
新疆维吾尔自治区高等学校科研项目(XJEDU2021I013)
NETL
NSTL
万方数据