内蒙古野生披碱草属牧草居群穗部形态多样性研究

Study on Ear Morphological Diversity of Elymus spp.Populations in Inner Mongolia

采用14项穗部形态学性状对内蒙古地区披碱草属牧草进行形态多样性研究,结果表明,14项穗部形态性状均存在较大的变异,平均变异系数为27.32%,变异系数最大为旗叶与穗基部长度(64.23%),最小为第一内稃长(12.25%)。14项穗部形态性状中小穗数的居群总多样性指数最高为2.051,最低的为每穗轴小花数(1.294)。披碱草属牧草种质资源遗传多样性丰富,居群内多样性指数最高为1.652(AE050),最低为1.019(AE027);居群总平均多样性指数为1.903,居群内平均多样性指数为1.407,表型分化系数为22.77%。14项穗部性状中穗长、穗宽、穗长、小穗数、第一颖长、每穗轴小花数和第一外稃长是引起表型变异的主要性状,这些性状与披碱草属牧草分类及种子产量密切有关。聚类分析表明,地理来源不同的同种材料能集中地聚在一起,说明相同物种即使地理位置相距较远,其亲缘关系仍然是最为接近,肥披碱草存在变异现象。此外,还提出了我国披碱草属牧草保护的策略。

Using 14 ear morphological characters to study morphological diversity of 24 Elymus spp. populations in Inner Mongolia, the results showed, they had large variation, and the average variation coefficient was 27.32%, and the largest variation coefficient was distance between boot leaf and ear, which was 64.32%, and the minimum was length of the first palea, which was 12.25%. And the largest genetic variation of the total populations was spikelet number in traits, which was 2.051, the smallest was flower number per spikelet, which was 1.294. Their genetic diversity was abundant, the highest genetic diversity index within populations was 1.654, which was AE050, and the lowest was 1.019, which was AE027. The average genetic diversity index of the total populations was 1.903, within was 1.407, and phenotypic differentiation coefficient was 22.77%. Primary traits of leading to morphological variation were spikelet length, ear width, ear length, spikelet number, the first glume letagth, flower number per spikelet and the first lemma length, and these traits were closely related to the classification of Elymus spp. and seed production. Cluster analysis showed that the different geographical origin of the same kinds of species can be concentrated together, indicating that the same species, even though far apart geographically, the closest genetic relationship was still, and E. excelsus of Inner Mongolia exist variation. Based oh the genetic information available for E. spp., some conservation strategies were proposed.