Drought resilience in CIMMYT maize lines adapted to Africa resulting from transpiration sensitivity to vapor pressure deficit and soil drying

Authors: CHIANGO, H - Eduardo Mondlane University; JAFARIKOUHINI, N - University Of Lisbon; PRADHAN, D - North Carolina State University; FIGUERIEDO, A - University Of Lisbon; SILVA, J - University Of Lisbon; SINCLAIR, T - North Carolina State University; Holland, Jim - Jim

Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/25/2021
Publication Date: 8/3/2021
Citation: Chiango, H., Jafarikouhini, N., Pradhan, D., Figueriedo, A., Silva, J., Sinclair, T.R., Holland, J.B. 2021. Drought resilience in CIMMYT maize lines adapted to Africa resulting from transpiration sensitivity to vapor pressure deficit and soil drying. Euphytica. 3:301-315. https://doi.org/10.1080/15427528.2021.1961334.
DOI: https://doi.org/10.1080/15427528.2021.1961334

Interpretive Summary: Drought tolerance in maize is associated with reduced transpiration (loss of water through the leaves, like perspiration) under low soil moisture. We screened maize lines from the international breeding program from CIMMYT and local Mozambique varieties for this reduced transpiration under low moisture stress trait. We identified two CIMMYT inbred lines and two local varieties that express this trait, indicating their potential usefulness in breeding for drought tolerance.

Technical Abstract: Currently limiting-rainfall amounts for crop production are likely to become even more severe as a result of climate change. This is certainly true for southern Africa where maize (Zea mays L.) is the most important staple food. Consequently, there is a need to identify genetic sources of specific drought-related traits that can contribute to soil water conservation and increased yields under water-limited conditions. In this study, maize genotypes released for production in southern Africa were tested for expression of two soil water-conservation traits: limited transpiration under elevated vapor pressure deficit (VPD) and decreased transpiration rate at high soil water contents earlier in the soil drying cycle. Two genotypes, namely CML 590 and CML 593, were identified and confirmed to express limited-transpiration rate at VPD of greater than about 1.9 kPa. In the soil drying experiment, Umbelu 8923 and Umbelu 8930 closed their stomata earliest in soil drying cycle as compared to other tested genotypes. These four genotypes with specific physiological traits for superior response to water deficit are suggested as genetic resources for further study for improved maize drought-tolerance.