Maize (Zea mays L.) is vital for global food security, and increasing its yield is a key goal in tropical breeding programs. A unique double-ear maize from Kadatua Island, Indonesia, produces two ears per plant—a promising trait for higher yield if properly developed. However, this germplasm has a low yield, and its phenology and inheritance pattern require further understanding. This study aimed to characterize its phenological development and key genetic parameters for breeding improvement. The recorded vegetative and reproductive growth stages used leaf collar and kernel development benchmarks, respectively. Genetic parameters, as calculated from progeny, utilized North Carolina Design-I. Results showed the vegetative stage was similar to that of commercial hybrids (4–58 days after planting), while the reproductive stage progressed more rapidly (58–83 days after planting). Genetic analysis revealed the dominance variance was greater than the additive variance (P: 0.00–0.05) for all traits, except plant height. Broad-sense heritability ranged from moderate to high (0.65–0.83), and narrow-sense heritability was low to moderate (0.01–0.37) for reproductive traits. Strong positive correlations occurred between ear weight, ear length, stem diameter, and grain yield. The study suggests hybrid breeding is a promising approach to improving yield in this double-ear maize.
Double-ear maize (Z. mays L.), phenological development, genetic parameters, heritability, dominance variance, hybrid breeding
The double-ear local maize cultivar exhibited vegetative growth duration comparable to commercial hybrids. Genetic analysis revealed the dominance variance and the high broad-sense heritability play a major role in the expression of reproductive traits. Hybrid breeding strategies hold considerable potential for improving yield in this locally adapted maize population.