增强小麦种子萌发期抗旱性的植物生长调节物质的筛选与评价

为筛选能增强小麦萌发期抗旱性的植物生长调节物质,以绵麦228为材料,选用21种植物生长调节物质浸种24h,以清水浸种为对照,在20%PEG6000模拟干旱胁迫条件下,测定各处理的小麦种子发芽势、发芽率、发芽指数及苗高、胚芽鞘长度、根长、根数、根冠比、种子贮藏物质转运率等性状,并通过加权隶属函数法评价21种生长调节物质增强小麦萌发期抗旱性的综合效果。结果表明,在PEG6000胁迫下,供试的大部分植物生长调节物质均能在一定程度上增强小麦种子萌发期的抗旱能力,表现为种子发芽率、发芽势、发芽指数提高,苗高、胚芽鞘长度、根长和根数增加,根冠比、贮藏物质转运速率增大;不同植物生长调节物质对小麦萌发期抗旱能力的调控程度存在一定差异。通过加权隶属函数法分析,综合评价值(D值)排在前5位的植物生长调节物质分别为乙烯利、黄腐酸、氯化胆碱、赤霉素、吲哚丁酸·萘乙酸。除根长、根冠比外,其他鉴定指标与D值均呈显著或极显著正相关,其中苗高的相关系数最大(0.80),因此种子发芽势、发芽率、发芽指数、苗高、胚芽鞘长度、根数、种子贮藏物质转运率等指标可作为植物生长调节物质浸种调控小麦萌发期抗旱性的评价指标。

Evaluation and Selection of Plant Growth Adjusting Substances Related to Enhancing Wheat Seed Germination under Drought Stress

The objective of this study was to screen plant growth adjusting substances related to enhancing wheat germination drought resistance,a hydroponic experiment was conducted to measure the germination potential,germination rate,germination index,seedling height,coleoptile length,radicle length,radicle number,root-shoot rate and storage transport rate of every soaking seed by plant growth substances under simulated drought stress with 20% PEG6000,with Mianmai 228 as material.The comprehensive evaluation of drought resistance during wheat germination was analysed by weighted membership functions and cluster analysis. The results suggested that most of the plant growth adjusting substances could increase during drought resistance wheat germination under PEG6000 stress.Germination potential,germination rate,germination index,seedling height,coleoptile length,radicle length,radicle number,root-shoot ratio and storage transport rate were increased,and there were certain differences in regulation ability of drought resistance for different plant growth adjusting substances during wheat germination.Based on the analysis with weighted membership function, the top five plant growth substances with high comprehensive evaluation value(D value)were ethrel,fulvic acid,choline chloride,gibberellin and indolebutyric acid·naphthalen acetic acid.The correlation analysis results showed that except for radicle length and root-shoot ratio each index showed significantly positive correlation with D value.Seedling height has largest correlation coefficient(0.80).We propose that the indices except for radicle length and root-shoot ratio can serve as the rapid identification indices for plant growth substances in soaking seeds during germination stage.