10个冬小麦品种萌发期抗旱性评价

郑立龙 李兴茂

摘要：以10个不同抗旱性差异的小麦品种为材料，利用不同浓度PEG进行胁迫处理，测定冬小麦胚芽长度、胚根数、胚根长度、芽鞘长度等4个生长指标，评价不同冬小麦品种萌发期的抗旱性能。结果表明，冬小麦萌发期抗旱性鉴定首先应选PEG25%浓度，依据致死程度确定出具有明显抗旱性差异的品种，然后在20%PEG浓度的胁迫下，根据各生长指标来综合分析品种的抗旱性差异。各生长指标对干旱环境的敏感性由强到弱为胚芽鞘长度、胚根长度、胚根数、胚芽长度，表明胚芽鞘长度可作为萌发期抗旱性最佳鉴定指标。与对照（无PEG胁迫）相比，陇鉴19、陇鉴196、西峰20号、陇鉴127等4个品种在25%PEG浓度下未发生致死，且在20%胁迫下胚根数、胚根长度、胚芽鞘长度、胚芽长度的变幅较小。因此，这4个品种抗旱性能强，为适宜的耐旱品种。

关键词：冬小麦;萌发期;抗旱性;渗透胁迫

中图分类号：S512.1       文献标志码：A        文章编号：1001-1463（2021）02-0070-06

doi：10.3969/j.issn.1001-1463.2021.02.018

Evaluation of Drought Resistance of Ten Winter Wheat Cultivars at Germination Stage

ZHENG Lilong 1， LI Xingmao 2

（1. Institute of Agricultural Economy and Information， Gansu Academy of Agricultural Sciences， Lanzhou Gansu 730070， China;2. Institute of Dryland Agricultural， Gansu Academy of Agricultural Sciences， Lanzhou Gansu 730070， China）

Abstract：The ten winter wheat cultivars of different drought resistance were used as material， and were stressed by different concentrations of PEG. The wheat germ length， the number of radicle， the radicle length and the coleoptile were analyzed after water stress， and then winter wheat drought resistance was evaluated. The results showed that PEG concentration should be chosen first 25% conditions for winter wheat germination drought resistance identification. According to the degree of death， the drought resistance were identified. Then under the stress of the PEG concentration of 20%， the difference of drought resistance were analyzed comprehensively according to the growth indexes. The growth index sensitivity to drought from strong to weak was coleoptile length， germs radicle length， germs radicle number， the radicle length. The results indicated that the length of the coleoptile sheath could be the best index for the identification of drought resistance during germination. Compared with the CK（no PEG stress）， Longjian 19， Longjian 196， xifeng 20 and Longjian 127 varieties did not happen to death under 25% PEG concentration， and under the stress of 20%， the range of radicle， radicle length， coleoptile， germ long were smaller. Therefore， the four varieties of drought resistance performance was good， which were the suitable varieties for drought resistance.

Key words：Winter wheat;Germination stage;Drought resistance;Osmotic stress

冬小麥是我国西北和华北半干旱地区主要的粮食作物。在冬小麦播种到出苗期，由于干旱少雨，给种子的萌发出苗造成了伤害，严重影响了其正常的生长发育和产量的提高[1 ]。应用抗旱性强的冬小麦品种，是适应播种出苗期土壤干旱的一条重要途径。作物的抗旱性是一个复杂的综合特性，发生在作物生长发育的不同阶段，作物在不同生育时期抵抗干旱胁迫的内在机制不同[2 ]。种子萌芽期抗旱性鉴定内容包括种子的发芽率、发芽势、萌发抗旱指数等，是鉴定玉米、小麦、水稻、高粱等作物整体抗旱性的重要指标[3 - 7 ]，具有一定的可靠性，但不同作物萌发期抗旱性的主要鉴定指标仍存在一定差异[8 - 9 ]。……