Understanding the interactions of genotype with environment and management (G×E×M) to maize productivity in Conservation Agriculture systems of Malawi.

Publisher: Public Library of Science Country of Publication: United States NLM ID: 101285081 Publication Model: eCollection Cited Medium: Internet ISSN: 1932-6203 (Electronic) Linking ISSN: 19326203 NLM ISO Abbreviation: PLoS One Subsets: MEDLINE

Original Publication: San Francisco, CA : Public Library of Science

Zea mays*/genetics ; Zea mays*/growth & development ; Agriculture*/methods ; Genotype*; Malawi ; Conservation of Natural Resources/methods ; Crops, Agricultural/genetics ; Crops, Agricultural/growth & development ; Gene-Environment Interaction ; Environment ; Soil/chemistry

Climatic variability and soil fertility decline present a fundamental challenge for smallholder farmers to determine the optimum management practices in the production of maize. Optimizing genotype (G) and management (M) of maize under different environmental conditions (E) and their interactions are essential for enhancing maize productivity in the smallholder sector of Malawi where maize is the main staple food. Here, we evaluated over seven seasons, the performance of four commercial maize genotypes [including hybrids and one open pollinated variety (OPV)] managed under different Conservation Agriculture (CA) and conventional practices (CP) across on-farm communities of central and southern Malawi. Our results revealed significant G×E and E×M interactions and showed that hybrids such as DKC 80-53 and PAN 53 outyielded the other hybrid and the OPV in most of the environments while the OPV ZM523 had greater yields in environments with above-average rainfall and shorter in-season dry spells. These environments received a maximum of 1250 mm to 1500 mm of rainfall and yet the long-term averages were 855 mm and 1248 mm, respectively. Despite yielding lower, the OPV ZM523 also exhibited higher yield stability across environments compared to the hybrid MH 30, possibly due to its resilience to drought, heat stress, and low soil fertility conditions which are often prevalent in the target communities. Conservation Agriculture-based practices outyielded CP across the genotypes and environments. However, amongst the CA-based systems, intercropping of maize with pigeonpea [Cajanus cajan (L.) Millsp] and cowpea (Vigna unguiculata Walp.) performed less than monocropping maize and then rotating it with a legume probably due to competition for moisture between the main and the companion crops in the intercrop. The key findings of this study suggest the need to optimize varietal and management options for particular environments to maximize maize productivity in Malawi. This means that smallholder farmers in Malawi should adopt hybrids and CA-based systems for enhanced yields but could also consider OPVs where the climate is highly variable. Further rigorous analysis that includes more abiotic stress factors is recommended for a better understanding of yield response.
Competing Interests: The authors have declared that no competing interests exist.
(Copyright: © 2024 Mhlanga et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Glob Food Sec. 2017 Mar;12:31-37. (PMID: 28580238)
Sci Rep. 2021 Apr 14;11(1):8101. (PMID: 33854170)
Funct Plant Biol. 2016 Jun;43(6):502-511. (PMID: 32480480)
Theor Appl Genet. 2021 Jun;134(6):1729-1752. (PMID: 33594449)
Microb Ecol. 2017 Jan;73(1):135-152. (PMID: 27538875)
J Exp Bot. 2016 Feb;67(3):567-91. (PMID: 26585226)
Theor Appl Genet. 2009 Sep;119(5):875-88. (PMID: 19578830)
Glob Food Sec. 2022 Mar;32:100589. (PMID: 35300043)
Front Plant Sci. 2020 Apr 15;11:410. (PMID: 32351526)
Curr Opin Plant Biol. 2018 Oct;45(Pt B):226-230. (PMID: 29779966)
Crop Sci. 2002 Jan;42(1):11-20. (PMID: 11756248)
Science. 2010 Feb 12;327(5967):812-8. (PMID: 20110467)

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Date Created: 20240429 Date Completed: 20240429 Latest Revision: 20240502

20240502

PMC11057976

10.1371/journal.pone.0298009

38683809