西南地区小麦品种萌发期抗旱性分析

以20份小麦品种为材料,采用20%PEG-6000溶液模拟干旱胁迫,研究小麦种子萌发期对渗透胁迫的响应,并进行抗旱性综合分析,筛选抗旱性鉴定指标。结果表明:PEG胁迫下,不同小麦品种的发芽势、发芽率、发芽指数、胚根长、胚根数、胚芽鞘长度、胚芽长等均有不同程度的降低,各个指标在不同品种间的降低幅度不同,平均降低幅度分别为59.1%、17.1%、51.7%、51.4%、18.5%、19.6%、71.1%;使用单一鉴定指标筛选出的抗旱性品种结果不一致;将隶属函数法与系统聚类法结合,筛选出蜀万8号为强抗旱型小麦品种,绵麦1403为弱抗旱型品种,川麦42和川麦55为不抗旱型品种,其余的为中间抗旱型品种;相关分析表明,相对发芽率与D值的相关性最大(0.90),可将其作为快速鉴定小麦品种抗旱性的指标。

The analysis of drought resistance in different wheat varieties during germination in southwest area of China

To identify drought resistance indexes, responses from twenty wheat varieties to osmotic stress during the germination period were studied by adopting 20% PEG-6000 solution as drought stress treatment, and the overall drought resistance capabilities were analyzed. The results showed that the germination potential, germination rate, germination index, radicle length, radicle number, coleoptile length and germ length of each variety were decreased under PEG stress, and these indexes of different varieties were reduced at different levels with average reduction rates at 59.1%, 17.1%, 51.7%, 51.4%, 18.5%, 19.6% and 71.1%, respectively. This was inconsistent with the results examined by varieties with single index of drought resistance. The combination of membership function method and system clustering method was used to have identified that Shuwan 8 was strong, Mianmai 1403 was weak, Chuanmai 42 and Chuanmai 55 were incapable, and the rest were moderate in drought resistance. Correlation analyses showed that the relative germination rate had the maximal positive correlation (0.90) with the D value, indicating that the relative germination rate could be used to provide fast identification of the drought resistance index in wheat.