不同小麦抗旱品种种子萌发的根系特征及其与主要激素含量的关系

摘要

为探究不同抗旱性小麦品种抗旱萌发的根系生长特征及其与主要激素含量的关系,以抗旱性较强的晋麦47和抗旱性较弱的矮抗58为材料,研究了正常和干旱(15% PEG)水分条件下小麦萌发期最长根长、根质量、总根长、根系总表面积等形态指标,以及根系中生长素(IAA)、细胞分裂素(CTK)、脱落酸(ABA)、赤霉素(GA)、乙烯(ETH)等激素含量的变化.结果表明,干旱胁迫下,与对照相比,晋麦47的最长根长增加(增幅为25.82%),矮抗58的最长根长减小(降幅为8.09%);两品种的根质量、总根长、根系总表面积、根系总体积均降低,且晋麦47的降幅均小于矮抗58;两品种根系中IAA含量、ABA含量、CTK含量、ETH含量均增加,且晋麦47的增幅均大于矮抗58;而GA含量均降低,且晋麦47的降幅大于矮抗58.这些结果说明,干旱条件下抗旱性强的小麦品种具有较长的最长根长,且与IAA,ABA,CTK,ETH的含量增加有关.%In order to explore the root growth characters of germination of different drought-resistant wheat cultivars and their relationship with main hormone contents,Jinmai 47 and Aikang 58 were used as materials in this study. Under different water conditions,changes of morphological indicators,inclu-ding the length of the longest root,root weight,total root length and total root surface area,five major categories of plant hormone contents were measured during the wheat germination period. The results showed that,under drought stress, compared with the respective controls, the longest root length of Jinmai 47 increased by 25.82%,while that of Aikang 58 decreased by 8.09%. In root system of the two cultivars,root weight,total root length,total root surface area and root volume all decreased,but less in Jinmai 47 than in Aikang 58. The contents of IAA, ABA, CTK and ETH all increased, and more greatly in Jinmai 47 than in Aikang 58. However,the content of GA decreased,and more greatly in Jinmai 47 than in Aikang 58. The results indicated that,under drought conditions,the drought-re-sistant wheat cultivars had the longest root length which was related to the increase of the contents of IAA,ABA,CTK and ETH.