六倍体小黑麦品种资源的抗旱性聚类分析

本研究选用10个六倍体小黑麦品种(系)为材料，利用20%PEG-6000模拟干旱，检测各品种芽期的发芽势、发芽率、胚芽鞘长、主根长以及苗期的POD和SOD活性、相对含水量、MDA含量，并计算各性状的抗旱系数（T/CK），根据抗旱系数的欧氏距离将其聚为两大类，一类为抗旱性强的S1、S3、S5、S8、 S10，另一类为抗旱性弱的S2、S4、S6、S7、S9。同时，利用RAPD分子标记分析其遗传多样性，以0.34为阈值将其分为三类，其中S4、S5为一类；S1、S2、S3、S6、S7、S8、S9为一类, S10自成一类。对比分析发现抗旱性强的一类品种分散分布在分子标记的三大类群里，表明这些分子标记与品种的抗旱性不相关。但反过来可以说明这些抗旱性强的品种其遗传差异较大，遗传变异丰富，为在小麦或小黑麦的抗旱育种中更好地利用这些品种资源提供了依据。

Cluster analysis of drought resistance in Hexaploid Triticale

The germinating potential, germination rate, Coleoptile length, radicle length and the activities of SOD and POD, relative water content and MDA content in 10 hexaploid triticale varieties were analyzed under 20%PEG-6000(W/V) stress, then drought-resistance coefficient of each trait was calculated. After clustered according to drought-resistance coefficient , 10 varieties were divided into two main groups: one group is S1, S3, S5, S8, S10, which has strong draught-resistant; The other group is S2, S4, S6, S7, S9, which has weak draught-resistant. On the other hand, 10 varieties were divided into three groups: S4, S5; S1, S2, S3, S6, S7, S8, S9; S10; using RAPD markers, based on 0.34 threshold value. In comparison with two clustering results, the strong draught-resistant varieties were scattered in three groups clustered on RAPD markers, indicating that these molecular markers are not related to draught resistance of the varieties. However, the results also showed that these drought-resistant varieties have quite different genetic diversity, which can provide a theoretical basis for using these variety resources in wheat or triticale’s draught-resistant breeding.