西北地区蚕豆苗期干旱胁迫下表型差异性与抗旱性研究

Study on phenotypic diversity and drought resistance of northwest broad bean seedling under drought stress

采用盆栽人工控水方法,选择西北地区7份蚕豆主栽品种为材料,研究不同水分胁迫(轻度LS和重度WS)下蚕豆苗期地上部、地下部及叶片生理生化指标与抗旱性的关系。结果表明,干旱胁迫对蚕豆幼苗地上、地下部分均有不同程度影响,幼苗株高、茎粗、叶面积、侧根数量及蚕豆主根长度生长受到抑制,且随干旱胁迫程度加剧,抑制作用明显(P<0.05),临蚕9号株高、茎粗、叶面积、主根长度均表现显著抑制作用,为干旱敏感性蚕豆品种;超氧化物歧化酶(SOD)活性和叶绿素含量(Chl)在水分胁迫下总体呈先升后降趋势,青海13号SOD活性上升幅度较大,抗旱性较强。叶片可溶性糖含量(WSS)和细胞质膜相对透性(REC)随干旱胁迫加重均有明显增加,WSS增加越快,抗旱性越强,REC则相反,抗旱性越强的品种,细胞质膜透性增加越少,而蚕豆叶片组织相对含水率(RWC)比正常供水的下降明显,且下降幅度小的品种抗旱性越强;通过隶属函数法综合评价苗期抗旱性大小为:青海13号>临蚕6号>青蚕14号>青海12号>马牙>临蚕9号>临蚕8号;通过主成分分析和灰色关联分析,筛选出WSS、REC、RWC、SOD等生理指标和株高、叶面积、根长等形态指标,可作为蚕豆品种苗期抗旱能力评价必不可少的指标。

By the method of potted artificial water controlled, the article studied the relationship of aboveground, underground part and the leaf physiological and biochemical indices in seven northwest origin broad beans under drought stress （LS and WS）. The results showed that drought stress had different influence on aboveground, underground part of broad bean seedling, drought stress inhibited the growth of plant height, stem diameter, leaf area, taproot length and the number of lateral root of broad bean, with the increase of drought stress, inhibitory effect was obvious （P〈0.05）, there were significant differences on plant height, stem diameter, leaf area and taproot length of Lincan9, which was drought sensitive broad bean. With the increases of drought stress the activity of SOD and chlorophyll content showed an decreasing trend, Qinghai13 SOD activity had increased significantly, showed drought tolerance. By the increasing of drought stress, the leaf soluble sugar content and cell membrane permeability had increased significantly, the more quickly WSS decreased, the stronger drought tolerance broad bean had, on the contrary, if a broad bean had strong drought tolerance, the increase of REC was small. While, the relative water content of broad bean leaf decreased more obviously than CK, and RWC of drought resistant cultivar decreased more slowly than the sensitive cultivar. The drought resistance of seven broad bean materials were arranged as the order from strong to weak： Qinghai13〉Lincan6〉Qingcan14〉Qinghai12〉Maya〉Lincan9〉Lincan8; Combined with principal components analysis and grey correlation analysis selected WSS, REC, RWC, SOD and plant height, leaf area, root length as broad bean seedling drought resistance evaluation indices.