Zhao Xuhong, Zhang Junchao, Zhang Zongyu, Wang Yanrong, Xie Wengang
The State Key Laboratory of Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020 People's Republic of China.
Hereditas. 2017 Dec 12;154:15. doi: 10.1186/s41065-017-0053-1. eCollection 2017.
is an important native grass in Qinghai-Tibetan Plateau. Seed shattering is a serious problem for , especially at harvest time. Cross breeding is an effective way to create new varieties with beneficial characteristic or improved traits, and to broaden genetic base.
In this study, we created five hybrid populations by crossing seven genotypes that have seed shattering variation. Then, nine EST-SSR primers were used for hybrid identification based on DNA fingerprinting, and genetic diversity analysis of hybrid populations and their respective parents. A total of 15 hybrids were identified. An analysis of amplified polymorphic bands among genuine hybrids and their respective parents revealed mainly two types of markers: 1) hybrids shared bands exclusively amplified in both parents; 2)hybrids shared bands exclusively amplified in male parents. For each hybrid population, the total number of amplified bands ranged from 37 to 57, the percentage of polymorphism varied from 65.12% to 75.68%, with an average of 70.51%. Novel bands found in each hybrid population varied from 0 to 9 bands, suggesting an occurrence of rearrangements in the hybrid population. The structure analysis revealed that all hybrid populations and parents were assigned to eight groups. The principal coordinate analysis (PCoA) showed similar results.
In general, this study proved EST-SSR markers are efficient for hybrid identification, and suggested more genetic variation could be captured in hybrid populations by crossing breeding.
是青藏高原一种重要的本土草种。种子散落是该草种面临的一个严重问题，尤其是在收获季节。杂交育种是创造具有有益特性或改良性状的新品种以及拓宽遗传基础的有效方法。
在本研究中，我们通过杂交七个具有种子散落变异的基因型创造了五个杂交群体。然后，使用九个EST-SSR引物基于DNA指纹图谱对杂交种进行鉴定，并对杂交群体及其各自亲本进行遗传多样性分析。共鉴定出15个杂交种。对真正的杂交种及其各自亲本之间扩增的多态性条带进行分析，主要揭示了两种类型的标记：1）杂交种共享仅在双亲中扩增的条带；2）杂交种共享仅在父本中扩增的条带。对于每个杂交群体，扩增条带总数在37至57条之间，多态性百分比在65.12%至75.68%之间，平均为70.51%。每个杂交群体中发现的新条带数量从0到9条不等，这表明杂交群体中发生了重排。结构分析表明，所有杂交群体和亲本被分为八组。主坐标分析（PCoA）显示了相似的结果。
总体而言，本研究证明EST-SSR标记对于杂交种鉴定是有效的，并表明通过杂交育种可以在杂交群体中捕获更多的遗传变异。
