Vigna is a genus of flowering plants in the legume family, and about 100 species belong to this genus, including azuki bean, blackgram and mungbean which are well-known in Asia. Among the species in Vigna genus, Vigna reflexo-pilosa has its own unique characteristic form as allotetraploid (2n=4x=44), whereas other Vigna species exist as a diploid form (2n=2x=22). In this study, we de novo assembled V. reflexo-pilosa genome and 22 accessions of 18 Vigna species’ transcriptome using NGS platform and calculated the Ks values of synteny blocks within V. reflexo-pilosa to determine the whole-genome duplication event existence. Two WGD events had occurred on V. reflexo-pilosa unlike V. radiata which only occurred once. Also, we tried to find out which progenitor had contributed to formation of V. reflexo-pilosa using transcriptome assemble results of 22 Vigna accessions. Ks value calculation between the transcriptome assemble results and predicted gene sets of V. reflexo-pilosa has been excuted. V. trinervia showed 2 peaks (0.0075, 0.0495) on its Ks value bin distribution and confirmed as A-type genome donor. Based on the peak value, we considered the predicted genes of V. reflexo-pilosa in Ks value range from 0.033 to 0.072 as B-type genes, inherited from other progenitor. Re-calculating the Ks values of 4,796 predicted genes in B-type with the transcriptome assemble results of 22 Vigna accessions, we were able to find 6 Vigna species, V. umbelleta(CIAT34386), V. umbelleta(2004T2), V. nakashimae, V. nepalensis, V. riukiuensis, V. minima as candidate B-type genome donor.

• Jayern Lee(Department of Plant Science and Research Institute for Agriculture and Life Sciences, Seoul National University) Corresponding Author
• Suk-Ha Lee(Department of Plant Science and Research Institute for Agriculture and Life Sciences, Seoul National University, Plant Genomics and Breeding Institute, Seoul National University)