Development of High Yielding Cowpea [Vigna unguiculata (L.) Walp.] Lines with Improved Quality Seeds through Mutation and Pedigree Selection Methods

Abstract

Cowpea [Vigna unguiculata (L.) Walp.] is a major legume crop and an important source of protein in Africa. The Kafr El-Sheikh University has a long history of cowpea breeding and improvement in Egypt. Two superior lines with high seed yield and quality were selected through mutation breeding and released to farmers as new varieties under the names Kafr El Sheikh-1 and Kaha-1. Crosses were made between these two varieties to further improve cowpea to meet farmers’ demand. Using the pedigree selection method, 13 new superior F10 lines were selected and evaluated over 2 years for seed yield and related traits, earliness, and protein content under low (16 plants/m2) and high (24 plants/m2) plant densities. The results showed that plants grown in narrower space produced significantly higher seed yield per unit area than the plants grown in wider space. All developed lines produced significantly higher seed yield than the two parental lines in the 2018 trial and Kaha-1 in the 2019 trial. Line number 6 proved to be the best genotype for earliness (73.5–73.9 days after sowing), seed yield (573–647 g/m2), and crude protein content (22.7–24.3%) in both trials. In addition, line 4 with bushy determinate growth habit and high seed quality was recently released as a new variety (Sakha-1). Several other cowpea lines have clear potential for release as new high-yielding varieties with early maturity and high seed quality for farmers in Egypt. Seeds of selected lines are available from Kafrelsheikh University. This shows that mutation breeding and pedigree selection methods are among the most promising breeding methods for cowpea improvement.