Identification of salt-tolerant cowpea genotypes using ISSR markers and proteome analysis

Soil salinity globally affects the productivity of staple food crops. Therefore, an understanding of the molecular mechanisms that lead to salt tolerance induced by antioxidant mechanisms can assist in the development of salt-tolerant crops. To decipher the molecular fingerprint of salt resistance, in this study, six salt-tolerant cowpea genotypes at the seedling stage were assessed for their antioxidant responses, yield, genetic polymorphism and proteomics under salt stress. Leaves and roots showed distinct tissue-specific responses to salinity, and leaves showed a better protection against salt stress-induced oxidative stress than roots. Inter simple sequence repeat (ISSR) fingerprinting allowed molecular discrimination between salt-tolerant cowpea genotypes. Proteome analysis of cowpea leaves under salt stress revealed up-regulation of ATP synthase, vacuolar ATPase, pentatricopeptide repeat protein, flavanone 3-hydroxylase and outer envelope pore protein. Thus, ISSR and proteome analysis allow the identification of salt-tolerant cowpea cultivars.