荒漠植物沙鞭(Psammochloa villosa)种质资源收集及谱系遗传分化初探

Germplasm Collection and Preliminary Studies on Genealogical Differentiation of A Desert Species—Psammochloa villosa

沙鞭(Psammochloa villosa)是禾本科(Poaceae)、针茅族(Stipeae)、沙鞭属(Psammochloa)中一个具有重要经济和生态价值的荒漠特有种,具有较强的抗逆性,是一种优质防风固沙植物,主要分布于内蒙古高原及其毗邻沙地。2013-2016年,本研究调查了沙鞭野生种质资源在内蒙古高原及其毗邻地区的自然地理分布,并在群体水平上收集了凭证标本、DNA材料和成熟种子;同时,从采集材料中选取具有代表性的180个个体进行了nrITS序列的扩增和测序,结果发现沙鞭所有参试种群的nrITS序列存在两个较为明显的谱系遗传分支,即一个分支主要由生长于内蒙古高原东部的所测个体组成,另一个分支由内蒙古高原西部的所测个体构成,这与依据外部形态特征和叶表皮微形态特征鉴分的结果相吻合。此外,本文还进一步讨论了这些丰富的种质资源对今后研究和利用沙鞭的重要性和相关途径。

Psammochloa villosa,belonging to the genus Psammochloaof the tribe Stipeae in the grass family（Poaceae）,is an endemic species in the desert regions with important economic and ecological values.It is distributed in the Inner Mongolia Plateau and adjacent areas.It is a good sand fixation plant and has strong stress resistance.From 2013 to 2016,we surveyed the natural distribution of this species in the regions and collected its germplasm resources comprising voucher specimens,DNA materials and mature seeds.In the meanwhile,we further amplified and sequenced nrITS sequences from 180 representative individuals selected from the collected populations.Based on the nrITS data fromPsammochloapopulations,the results showed that there were two major distinct genetic branches.One branch is mainly composed of measured individuals growing in the eastern Inner Mongolia Plateau,the other branch consists of individuals in the western Inner Mongolia Plateau.This is consistent with the results obtained from morphological and leaf epidermal micromorphological features.In conclusion,these data supply important resources for further utilizing and studying this species.