Cowpea [Vigna unguiculata (L.) Walp.] is one of the most important and strategic food sources for tropical and subtropical regions of the world. Cowpea grain contains a high proportion of protein (19% to 35%) and carbohydrates (63%), with low fat content (1.5%) (Xiong et al., 2016). The crop has an important role in promoting global food security due to its nutritional characteristics and because it is considered undemanding in terms of production, making it possible to grow under low-input production systems (Horn and Shimelis, 2020). This crop has been increasingly studied in Brazil because it is grown in a wide range of environments (Santos et al., 2014, 2019), making the development of improved local varieties for traits of interest an essential task.
Despite being considered an undemanding, tropical crop with wide adaptation to diverse environments, cowpea presents a low average yield (≈0.3 Mg·ha−1), even though there is evidence that its genetic potential is from 1.5 to 3.0 Mg·ha−1 (Gbaye and Holloway, 2011) and may even exceed 6.0 Mg·ha−1 (Ehlers and Hall, 1997). The first step for developing genotypes with greater yields is the choice of parents, which need to have genetic divergence between them and alleles favorable for better agronomic traits of commercial interest. Therefore, genetic diversity studies are necessary to assist breeders in determining the most promising hybrid combinations (Ribeiro et al., 2019; Santos et al., 2014).
In addition to grain yield, other traits of Brazilian cowpea genotypes need to be improved. The mass of 100 grains is a trait that has a direct association with yield and a direct impact on consumption because consumers prefer heavy grains. Other agronomic traits, such as plant architecture and tolerance to lodging, are also important because they affect losses during mechanized harvest. Finally, cultivation value is constituted by a scoring scale in which the breeder evaluates whether the genotype comprises agronomic and commercial traits that are favorable to cultivation (Guerra et al., 2017).
The objective of this study was to analyze the genetic diversity of cowpea genotypes to identify promising crossings for the Brazilian Cerrado based on agronomic traits.
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Ribeiro, L.P., Evangelista, J.S.P.C., Damacena, M.B., Elizeu, A.M., Coelho, I.F., Rodrigues, E.V., Teodoro, P.E. & Bhering, L.L. 2019 Estimates of genetic divergence in cowpea by multivariate analysis in different environments Biosci. J. 35 1681 1687 doi: 10.14393/BJ-v35n6a2019-42406
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Mean square of the joint variance analysis for traits growth type (GT), cultivation value (CV), lodging (LOD), architecture (ARC), mass of 100 grains (MHG), and grain yield (GY) evaluated in 20 cowpea genotypes.