Comparative Transcriptomic Analysis Revealed Complex Molecular Mechanisms Underlying Pests, Pathogens Resistance and Seed Development in Wild and Cultivated Blackgram

Blackgram is a widely cultivated pulse crop in Asia. Bruchid pests and yellow mosaic disease (YMD) causes huge loss in legume production including blackgram. Blackgram wild accession (Vigna mungo var. silvestris), Trombay wild urd (INGR10133) conferred resistance to bruchids especially Callosobruchus maculatus, through antibiosis. However, the mechanisms still remains uncharacterized. We performed the comparative transcriptome analysis of the developing seeds of wild and cultivated blackgram with contrasting phenotypes for 3 traits, bruchids infestation, YMD and seed size. In this study,715differentially expressed genes(DEGs) were re-annotated with reference to NCBI nr database. RNA-Seq was validated by quantitative real-time PCR for 22 DEGs. In Trombay wild, defense related components such as acid phosphatase, vicilins, trypsin inhibitor, brassinosteroid signalling components were found up-regulated. While in cultivar, transcripts for LEA, cysteine protease, autophagy related proteins(ATG3, ATG5, ATG8C and ATG1t), DnaJ, tobamovirus multiplication protein, downy mildew resistance protein, LRR/F-box proteins were found up-regulated. In TW, three transcripts were found common for both bruchids pest and geminivirus resistance (LRR receptor kinase, transmembrane protein 87b and thaumatin like protein).Our study is the first report on transcriptomic differences between wild and cultivated blackgram with new insights into the molecular networks underlying seed development, resistance to pests and pathogens.