By Abiola Toyin Ajayi
Cowpea (Vigna unguiculata L. Walp) is a crop of significant importance in Africa; it serves as a source of proteins in the tropical and subtropical countries, where Nigeria is ranked the highest in terms of production. It is a source of income for the people of Africa where it is widely cultivated for different purposes. Despite the good attributes of cowpea, one of the major constraints hampering its productivity in Nigeria is drought.
Breeding of genotypes with high levels of tolerance to drought stress for all stages of growth and development are desirable to sustain yield. Nevertheless, breeding for drought must be done with consumer acceptability considerations to prevent drawbacks that might arise from rejection of improved varieties; as utilization of the crop in Africa is heavily dependent on consumer preference.
One of the most important attributes of cowpea influencing its acceptability and its introduction to markets is the seed coat colour which has been a subject of study for ages, with the genetic factors underlying their expression elucidated. There are various patterns of seed coat displayed by cowpea seeds and the preferred colours and pigmentations are region specific. According to Egbadzor et al. in 2014, the seed coat colour and pigmentation in crop plants are influenced by anthocyanin syntheses and controlled by some anthocyanin genes (like pac 1 gene) which are abundant in plants and important to plants in signaling abiotic stress such as drought.
Seed coat colour and pigmentation inheritance in cowpea has been reported to be quantitative in nature involving several genes, contrary to the findings of Yilwa in 2012. These numbers of genes involved have been attributed to the seed coat colour combinations of the parental lines involved in specific crosses .
Development of improved cultivars for any constraint requires combination of genotypes of diverse origins as parental stocks. Adapted individuals in terms of specific constraints in a particular ecology are normally the best sources of genes for breeding improved varieties. A larger genetic variability in existence in the tropics among cowpea genotypes serves as a source of information for developing hybrids for specific constraints. However, proper choice of parents is critical to a successful breeding program of cowpea because of limitations resulting from hybridization for inheritance of polygenic traits. Therefore, information on genetic compatibility and inheritance of seed coat colour and their relationship with drought tolerance in cowpea would contribute positively to the improvement of the crop through hybridization.
The research aimed at studying the level of crossability between two cowpea accessions and inheritance of seed coat colour in F1 generation has been carried out by the authors below.
Abiola Toyin Ajayi, Alaba Emmanuel Gbadamosi, Olanrewaju Folusho Olotuah, Ebenezer Adewale David. Crossability and inheritance of seed coat colour in cowpea at F1 generation. Frontiers in Life Sciences and Related Technologies 1(2) (2020) 58-62.