Heritability for Morphological Traits Determine Adaptability of Elite Cowpea Genotypes in different Environments

Lack of improved and high-yielding adapted varieties constitutes limitation to cowpea (Vigna unguiculata (L.) Walp) production in South Africa. Therefore, field trials were conducted in two locations (the University of Limpopo Experimental Farm, (Mankweng) and Towoomba Research Station, Bela-Bela) during 2015–16 and 2016–17, to assess yield components, genotype x environment interaction as well as the adaptability of elite cowpea genotypes. The experiment was laid out using a randomized complete block design in three replications. Data were collected on flowering, maturity and yield components. Results revealed that “genotype, and genotype × year and genotype × location interactions were significant for most of the traits evaluated”. „The days to 50% flowering‟ and „90% maturity‟ ranged between 53 and 60 days, and between 89 and 96 days, respectively. The „100-seed weight‟ varied from 15.8 g to 22.5 g. „Broad-sense heritability‟ varied from 0 to 93% for days to maturity and grain yield, respectively. „Grain yield‟ varied from 1465.7 to 2594.9 kg ha-1, and the best yielders were lines „L2‟, „L10‟, and „L7‟. The „PC1‟ and „PC2‟ explained 82.57% variation for maturity, 79.12% for the „pods per plant‟, 83.78% for „seeds per pod‟, 93.09% for „100-seed weight‟ and 95.84% for „grain yield‟. Towoomba was a more productive location compared to Sykerfuil. Lines „L2‟, „L10‟, and „L7‟ yielded very well in both locations and years. This implies that they are adapted and are recommended for registration and commercial release in the region. © 2021 Friends Science Publishers