Influence of genotype and environment on grain yield among cowpea (Vigna unguiculata (L.) Walp) genotypes under dry land farming system
The identification of high-yielding and stable genotypes for cultivation across differential production regions is among the key breeding objectives in cowpea improvement programs. This study was aimed to determine genotype-by-environment interaction (GEI) for grain yield to select high-yielding and stable cowpea genotypes for production in South Africa and identical agro-ecologies, and for cultivar development. Fifty cowpea genotypes were tested for grain yield across seven environments of South Africa using a 10 × 5 alpha lattice design replicated three times, during the 2019/2020 and 2020/2021 planting seasons. Grain yield data were subjected to analysis of variance (ANOVA), additive main effects and multiplicative interaction (AMMI) and the genotype-by-environment interaction (GGE) biplot analyses. ANOVA and AMMI showed significant genotype, environment and GEI effects. High grain yield was recorded for genotypes G35 (0.47 t ha−1), G1 (0.45 t ha−1) and G47 (0.43 t ha−1) across test environments. AMMI stability values (ASV); identified Acc-Cowp44 as the most stable genotype across all sites, recording the lowest ASV of 0.03. The comparison view of GGE biplot revealed Acc-Cowp29, Acc-Cowp38 and Acc-Cowp5 as ideal genotypes, possessing high grain yield of 0.19, 0.47 and 0.36 t ha−1 , respectively. The identified genotypes are recommended for production and inclusion in subsequent breeding activities.
Acknowledgements: The Agricultural Research Council (ARC) in South Africa is acknowledged for the provision of elite cowpea genotypes, and National Research Foundation (NRF) for funding the project. The Version of Scholarly Record of this Article is published in Acta Agriculturae Scandinavica, Section B — Soil & Plant Science, 2022, available online at: http://www.tandfonline.com/10.1080/09064710.2022.2069593 . © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Keywords: AMMI; ASV; GEI; GGE biplot; stability; Vigna unguiculata; yield; dry land farming; Africa; South Africa.
Mbali Thembi Gumede, Abe Shegro Gerrano, Albert Thembinkosi Modi & Zamalotshwa Thungo (2022) Influence of genotype and environment on grain yield among cowpea (Vigna unguiculata (L.) Walp) genotypes under dry land farming system, Acta Agriculturae Scandinavica, Section B — Soil & Plant Science, 72:1, 709-719, DOI: 10.1080/09064710.2022.2069593