Exploring the Genetic Basis of Root Mucilage in Cowpea (Vigna unguiculata (L.) Walp.)

Abstract

Cowpea (Vigna unguiculata (L.) Walp.) is a member of the legume family, Fabaceae. Cowpea varieties are vital agricultural crops in arid and semi-arid environments in Africa, Asia, India, and Central America. Cowpea sold in the United States is commonly known as black eyed peas. Breeding for specific cowpea varieties depends on environmental conditions where phenotypic traits may relate to drought tolerance, and resistance to fungal and bacterial pathogens, aphids, nematodes, viruses, and many others. The agricultural production of a variety with desirable traits is an important economic consideration that ultimately determines yield and quality of a harvest. The objectives of this study include phenotyping diverse germplasm for the mucilage trait, testing one or more candidate genes for polymorphisms, and the chemical quantitation and characterization of root mucilage. Phenotypes of several hundred cowpea germplasm accessions were compared to their existing SNP haplotypes spanning the region of interest to categorize haplotypes containing different alleles for the root mucilage trait. The gene sequences of different alleles for two candidate genes were determined for comparison between lines. Root mucilage will evenutally be analyzed for protein and carbohydrate content and specifically for arabinogalactans and proteins (Moody et al. 1988).