Evaluation of nutritional and phytochemical variability of cowpea Recombinant Inbred Lines under contrasting soil moisture conditions in the Guinea and Sudan Savanna Agro-ecologies

Abstract

A B S T R A C TPlant breeders' efforts in developing drought tolerant and high-yielding cowpea varieties may be in vain unless the developed varieties are evaluated to ascertain the influence of water stress on their nutritive value, antioxidants, and phenolic contents under contrasting moisture regimes. The study was set up to evaluate the nutritional value, phytochemical content and antioxidant activity of cowpea Recombinant Inbred Lines (RILs) under contrasting soil moisture in the Guinea and Sudan Savanna agro-ecologies of Ghana. Forty-eight cowpea RILs seed samples from well-watered and water stress experiment were pulverized. Distillation and titration was carried out and the organic samples extracted and various biochemical analyses were carried out using standard protocols and methodologies. The dried grain mineral contents were determined using an Atomic Absorption Spectrophotometer, while the protein content was determined by the combustion method. Correlation and regression analysis and principal component analysis were performed using STATA version 13. Biochemical analysis for seed related traits revealed that inbred lines responded differently to drought. Significant differences of watering regimes on various phytochemical traits were only observed in phosphorus and lead. Inbred line with family number 57 had the highest crude protein content of 46.90% under well-watered conditions. Inbred line 84 under water stress conditions had high levels of Mg and K. Inbred line 20 under well-watered conditions had the highest antioxidant content. For phenolic acid content, inbred line 255 scored the highest. Quercetin and rutin were most abundant in inbred line 186 for both water-stress and well-watered conditions. The indication is that moisture stress could affect seed yield but no effects on the phytochemical and nutritional variables. Genotypic differences could arise from parental combination used for developing the inbred lines for the study.

Genetic variability, heritability and correlation analysis among maturity and yield traits in Cowpea (Vigna unguiculata (L) Walp) in Northern Ghana

“…Cowpea ( Vigna unguiculata (L) Walp) is one of the most important grain legumes in the sub-Saharan Africa and other developing countries ( Dube and Fanadzo, 2013 ). The grain of cowpea contains 21–33 % protein, 57 % carbohydrate, and a rich source of calcium and iron, while the leaves contain between 27-34% protein ( Belane and Dakora, 2009 ; Sefa-Dedeh et al., 2001 ; Boukar et al., 2011 ; Alidu et al., 2020 ). In addition, the grain contains some amounts of β-carotene, thiamin, riboflavin, folic acid and zinc ( Gonçalves et al., 2016 ; Tindall, 1983 ; Owade et al., 2020 ).…”

Application of biochar and inorganic phosphorus fertilizer influenced rhizosphere soil characteristics, nodule formation and phytoconstituents of cowpea grown on tropical soil

“…Cowpea is an important legume in most SSA countries as the grains, roots and leaves serve as major source of protein for people and as sources of feed for animals ( Quaye et al., 2009 ; Timko and Singh, 2008 ). Cowpea is reported to be rich in phytochemicals, such as phenols, flavonoids and alkaloids ( Alidu et al., 2020 ; Sivakumar et al., 2018 ; Sombié et al., 2018 ). The phytochemicals have medicinal uses and as important secondary metabolites, they moderate, soil-plant-microorganism interactions including alellopathy, defense against cowpea diseases and pest, nodulation, nutrient fixation and N uptake ( Aniszewski, 2007 ; Bhattacharya et al., 2010 ; Hu et al., 2005 ).…”

Genetic control of earliness in cowpea (Vigna unguiculata (L) Walp)

“…Millions of people in SSA consume the protein-rich cowpea grains and leaves as food, while the haulm constitute an important source of nutrient for livestock (Dakora and Belane, 2019). Alidu et al (2020) identified a cowpea genotype with high crude protein content of 46.90 %. Its nitrogen fixing ability through symbiotic association with Brady rhizobium spp.…”

“…Genetic estimates of agronomic traits are influenced by the type of genetic material (Alidu et al, 2020), sample size, method of sampling, method of calculation and effect of linkage (Said, 2014). Gaur et al (2014) classified F 2 plants of chickpea into two classes, late and early (early and extra-early) and found good fit to a 9:7 ratio in all the crosses, instead of 9:6:1 for late, early and extra-early, respectively.…”