Maize landrace accessions constitute an invaluable gene pool of unexplored alleles that can be harnessed to mitigate the challenges of the narrowing genetic base, declined genetic gains, and reduced resilience to abiotic stress in modern varieties developed from repeated recycling of few superior breeding lines. The objective of this study was to identify extra-early maize landraces that express tolerance to drought and/or heat stress and maintain high grain yield (GY) with other desirable agronomic/morpho-physiological traits. Field experiments were carried out over two years on 66 extra-early maturing maize landraces and six drought and/or heat-tolerant populations under drought stress (DS), heat stress (HS), combined both stresses (DSHS), and non-stress (NS) conditions as a control. Wide variations were observed across the accessions for measured traits under each stress, demonstrating the existence of substantial natural variation for tolerance to the abiotic stresses in the maize accessions. Performance under DS was predictive of yield potential under DSHS, but tolerance to HS was independent of tolerance to DS and DSHS. The accessions displayed greater tolerance to HS (23% yield loss) relative to DS (49% yield loss) and DSHS (yield loss = 58%). Accessions TZm-1162, TZm-1167, TZm-1472, and TZm-1508 showed particularly good adaptation to the three stresses. These landrace accessions should be further explored to identify the genes underlying their high tolerance and they could be exploited in maize breeding as a resource for broadening the genetic base and increasing the abiotic stress resilience of elite maize varieties.

https://dx.doi.org/10.3390/agronomy10030318

Multi standard citation

APAHarvardMLAVancouverChicagoIEEE

BAFFOUR BADU-APRAKUhttps://orcid.org/0000-0003-0113-5487

Garcia-Oliveira ALhttps://orcid.org/0000-0001-8561-4172

https://dx.doi.org/10.3390/agronomy10030318

Biotech and Plant Breeding

Agronomy; Climate Change; Maize; Plant Breeding; Plant Genetic Resources; Plant Production

Abiotic Stress; Climate Change; Drought Stress; Stress; Genetic Resources; Maize

Africa; West Africa

Burkina Faso (Upper Volta); Ghana; Nigeria; Togo

Headquarters and Western Africa Hub

Agronomy