Enhancing Food Security in a Changing Climate: Evaluating Yield Performance and Trait Correlations of Experimental Double Cross Maize Hybrids in Zimbabwe

Abstract

Maize (Zea mays L.) is a cornerstone crop for global food security, yet smallholder farmers in Zimbabwe face formidable challenges due to climate change impacts and the prohibitive costs of maize seeds. This study assessed the grain yield and yield components of experimental double cross maize hybrids (DCH) derived from diverse heterotic combinations, while also exploring correlations between yield and its components. The field experiment which was conducted at Tocek Investments research field in Harare, Zimbabwe comprised of 156 treatments which were laid in an Alpha (0.1) lattice design with two replications. Significant differences (p < 0.05) were observed across various traits. ENT 156 (a single cross commercial check) recorded the highest yield of 16.21 t/ha. This yield was however not significantly different from the yield recorded in ENT 142, ENT 41, ENT 32, and ENT 63. These 4 were all DCH hybrids with yields of 15.1 t/ha, 15 t/ha, 15 t/ha and 14.5 t/ha respectively. Additionally, ENT 63 (DCH) exhibited the highest number of kernels per row (NKR) at 42, while ENT 32 (DCH) recorded the highest number of kernel rows per cob (NKRC) at 15.5. However, no significant differences were detected for the number of ears per plant (NEP) among genotypes. Positive and significant genotypic correlation of grain yield with CL, NKRC, NKR, AD and SD serve as reliable indicators and selecting for them in double cross maize hybrid populations may lead to a substantial improved grain yield. It revealed that such traits strongly influenced grain yield. The genotypic correlation coefficients exhibited greater magnitudes for the majority of the traits in relation to grain yield than the phenotypic correlation coefficients. These findings underscore the potential of high-yielding DCH hybrids in addressing food insecurity among smallholder farmers. It is recommended that further validation of these hybrids under actual farming conditions be conducted to verify their performance and guide adoption strategies, thus offering a promising pathway towards enhanced agricultural resilience in the face of climate change.