Jain Shalu, Kumar Ajay, Mamidi Sujan, McPhee Kevin
Department of Plant Sciences, North Dakota State University, Fargo, ND, 58108, USA.
Mol Biotechnol. 2014 Oct;56(10):925-38. doi: 10.1007/s12033-014-9772-y.
Field pea (Pisum sativum L.) is an important cool season legume crop widely grown around the world. This research provides a basis for selection of pea germplasm across geographical regions in current and future breeding and genetic mapping efforts for pea improvement. Eleven novel genic markers were developed from pea expressed sequence tag (EST) sequences having significant similarity with gene calls from Medicago truncatula spanning at least one intron. In this study, 96 cultivars widely grown or used in breeding programs in the USA and Canada were analyzed for genetic diversity using 31 microsatellite or simple sequence repeat (SSR) and 11 novel EST-derived genic markers. The polymorphic information content varied from 0.01-0.56 among SSR markers and 0.04-0.43 among genic markers. The results showed that SSR and EST-derived genic markers displayed one or more highly reproducible, multi-allelic, and easy to score loci ranging from 200 to 700 bp in size. Genetic diversity was assessed through unweighted neighbor-joining method, and 96 varieties were grouped into three main clusters based on the dissimilarity matrix. Four subpopulations were determined through STRUCTURE analysis with no significant geographic separation of the subpopulations. The findings of the present study can be used to select diverse genotypes to be used as parents of crosses aimed for breeding improved pea cultivars.
豌豆（Pisum sativum L.）是一种重要的冷季豆类作物，在世界各地广泛种植。本研究为当前及未来豌豆改良的育种和基因定位工作中跨地理区域选择豌豆种质提供了依据。从豌豆表达序列标签（EST）序列中开发了11个新的基因标记，这些序列与蒺藜苜蓿的基因调用具有显著相似性，且跨越至少一个内含子。在本研究中，使用31个微卫星或简单序列重复（SSR）标记和11个新的EST衍生基因标记，对在美国和加拿大广泛种植或用于育种计划的96个品种进行了遗传多样性分析。SSR标记的多态信息含量在0.01 - 0.56之间，基因标记的多态信息含量在0.04 - 0.43之间。结果表明，SSR和EST衍生的基因标记显示出一个或多个高度可重复、多等位基因且易于评分的位点，大小在200至700 bp之间。通过非加权邻接法评估遗传多样性，并根据差异矩阵将96个品种分为三个主要聚类。通过STRUCTURE分析确定了四个亚群，亚群之间没有明显的地理分隔。本研究的结果可用于选择不同的基因型作为杂交亲本，以培育改良豌豆品种。
