Genetic diversity of zombi pea (Vigna vexillata) assessed by microsatellite markers

P. Somta, S. Dachapak, T. Yimram, P. Srinives, S. Poonchaivilaisak
Zombi pea (Vigna vexillat) is a legume crop originated in Africa of which the seeds and tuberous roots are edible. The tuber from zombi pea contains about 15% protein. At present, however, only a few cultivars of the tuberous type are grown in a small area of Bali, Indonesia, while cultivars of the seed type are possibly no longer cultivated. The wild form of this crop has a wide distribution throughout Africa, Asia, Australia and America. Zombi pea is resistant to several insects and tolerant to drought and waterlogging, and thus useful as a gene source in plant breeding. The aim of this study was to assess genetic diversity and genetic structure of wild zombi pea from America (73 accessions), Africa (21 accessions) and Austronesia (2 accessions) by using 11 microsatellite (simple repeat sequence; SSR) markers. The microsatellite markers detected 69 alleles in total, varying between 3 (VES0476) and 13 (CEDG214) alleles per marker with a mean of 6.28. Gene diversity (HE) was highest in accessions from Africa (0.66) followed by those from America (0.43) and Austronesia (0.42) with the overall value of 0.53. The markers showed polymorphism information content (PIC) values ranging between 0.12 (CEDG091) and 0.83 (CEDG214) with a mean of 0.49. The estimated out-crossing rate of zombi pea was high, being 39.14%. Neighbor-joining analysis, principle component analysis, and STRUCRTURE analysis revealed that the 96 accessions were separated into two major groups; one group comprised accessions from America, Austronesia and one accession from Africa, while the other group consisted of all accessions from Africa. These results supported the view that zombi pea is originated in Africa and showed that it has a moderate genetic diversity.
Somta, P., Dachapak, S., Yimram, T., Srinives, P. and Poonchaivilaisak, S. (2019). Genetic diversity of zombi pea (Vigna vexillata) assessed by microsatellite markers. Acta Hortic. 1241, 143-150
DOI: 10.17660/ActaHortic.2019.1241.21
Vigna, tuberous legume, simple sequence repeat, SSR, underutilized crop

Acta Horticulturae