Evaluation of Sucrose Content in Cowpea Seed

Cowpea (Vigna unguiculata (L.) Walp) is a worldwide legume crop to provide mineral, protein, oil, starch, soluble sugar and vitamins for human consumption and animal feeding. The content of soluble sugar is an important agronomic trait in cowpea. It does provide energy to human body, but also increases the tasty and mouthfeel of cooking quality. Therefore, this research aimed to evaluate variation of cowpea seed soluble sugar content, study genetic diversity, and develop high soluble sugar content varieties for cowpea breeding program. Spectrophotometer is a traditional method to use to measure seed soluble sugar seeds at lab. A total of 95 cowpea genotypes, including 50 USDA germplasm accessions and 45 advance cowpea breeding lines collecting from different location. The seeds of all tested cowpea genotypes were harvested in fall 2015 at University of Arkansas Research and Extension Station, Fayetteville, and Hope, Arkansas. The results showed that the seed soluble sugar content in tested cowpea genotypes exhibited a wide range from 4.140% to 14.83% with an average of 6.912%, based on the standard cures Y=0.0039X +0.0235(R² =0.99878). The top five cowpea accessions with highest seed soluble sugar are “Ebony” in Hope (14.828%), PI664524 (10.695%),”09-741”in Fayetteville (9.499%), “09-686” in Fayetteville (9.520%), and “09-692” in Fayetteville (8.655%), which can be used in cowpea breeding program as parents to develop superior new cowpea cultivars with high soluble sugar content.