J Syst Evol ›› 2022, Vol. 60 ›› Issue (1): 85-100.DOI: 10.1111/jse.12710

• Research Articles • Previous Articles     Next Articles

Population genetic structure and classification of cultivated and wild pea (Pisum sp.) based on morphological traits and SSR markers

Rong Liu1†, Yu-Ning Huang1†, Tao Yang1, Jin-Guo Hu2, Hong-Yan Zhang1, Yi-Shan Ji1, Dong Wang1, Guan Li1, Chen-Yu Wang1, Meng-Wei Li1, Xin Yan1, and Xu-Xiao Zong1*   

  1. 1 National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
    2 USDA, Agricultural Research Service, Western Regional Plant Introduction Station, Washington State University, Pullman, WA 99164, USA

    These authors contributed equally to this work.
    *Author for correspondence. E‐mail: zongxuxiao@caas.cn; Tel./Fax: 86‐10‐62186651.
  • Received:2020-04-09 Accepted:2020-11-15 Online:2020-11-22 Published:2022-01-01

Abstract: Pea (Pisum sativum L.) is an important legume crop that is widely grown worldwide for human consumption and livestock feed. Despite extensive studies, the population genetic structure and classification of cultivated and wild pea (Pisum sp.) remain controversial. To characterize patterns of genetic and morphological variation and investigate the classification of Pisum, we conducted comprehensive population genetic analyses for 323 accessions from cultivated and wild pea, representing three species of Pisum and utilizing 34 morphological traits and 87 polymorphic simple sequence repeat markers. First, we identified three distinct genetic groups among all samples. Group I was primarily composed of Pisum fulvum, Pisum abyssinicum, and some wild P. sativum accessions, whereas Groups II and III consisted of the two genetic groups under P. sativum that represented different geographic distributions of cultivated pea. Analyses of morphological variation revealed significant differences among the three species. Second, among pea germplasms representing eight taxa of Pisum, P. fulvum and P. abyssinicum possessed unique genetic backgrounds and morphological characteristics, corroborating their independent species status. The intraspecific subdivisions of P. sativum described by some authors were not supported in this study, with the exception of several genotypes of P. sativum subsp. elatius that clustered with P. fulvum and P. abyssinicum. Finally, we confirmed that the Chinese pea germplasm was genetically distinct and could be divided into two genetic groups, each of which included both spring-sowing and autumn-sowing ecotypes. These results provide a robust foundation for understanding pea domestication and the utilization of wild genetic resources of pea.

Key words: pea (Pisum sativum L.), Pisum L., population genetic structure, classification, SSR markers, morphological traits