|XINGBO, WU - Tennessee State University|
|NANA, LI - Shandong Research Institute|
|JUNJIE, HAO - Beijing Academy Of Agricultural Sciences|
|XIAOYAN, ZHANG - Beijing Academy Of Agricultural Sciences|
|BLAIR, MATTHEW - Tennessee State University|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/10/2016
Publication Date: N/A
Interpretive Summary: Both U.S. and China hold extensive pea germplasm collections. Although these two collections have similar number of accessions, the difference is that the Chinese collection contains predominately materials collected within China while the US collection comprises materials from all over the world. Each of these two collections has its own core collection (5% of selected accessions representing 95% of the genetic variation of the entire collection), 295 and 305 accessions for the Chinese and US global collections, respectively. We compared the genetic diversity in the two core collections based on the genotyping data of 30 informative microsatellite markers, which revealed a high level of genetic diversity with a total of 259 alleles. Our result showed that the US global core is more diverse than the Chinese core and that certain variation in the Chinese core is underrepresented in the US global core. Germplasm exchange between these countries for crop improvement will broaden the genetic base of the pea crop and enhance its productivity.
Technical Abstract: Pea (Pisum sativum L.) is an important food and feed legume grown across many temperate regions of the world, especially from Asia to Europe and North America. The goal of this study was to use 30 informative pea microsatellite markers to compare genetic diversity in a global core from the USDA and a core collection from National Genebank of China (NGC). The Chinese and global collections had 295 and 305 accessions, respectively. A total of 259 alleles were detected in the full 600 accessions, with a mean 8.7 alleles per locus. Given the range of countries represented, the global collection was found to be more diverse than the Chinese core. However, the Chinese accessions still formed two distinct groups. The first group had 90.6% spring planted peas from northern China. The second group had 65.9% winter planted peas from southern China. An outlier group included wild peas from the P. sativum ssp. elatius and asiaticum subspecies. In conclusion, the USDA collection had slightly more overall diversity than the NGC collection given its global nature, but the Chinese accessions represented a considerable fraction of overall diversity with accessions representing spring and winter pea types from northern and southern China, respectively, that are only weakly represented in the USDA core. The origin of Chinese peas is likely to be from the region of domestication in the Middle East through an ancient route of dissemination through Southern Asia, including the region of present-day Afghanistan, India, Nepal and Pakistan, where some genetically similar peas are grown.