Selection of Maize Hybrids Resulting from Line × Tester Crossing Tolerant to Drought Stress

Efforts to enhance maize productivity in regions like Madura Island, Indonesia, plagued by low yields due to drought stress, necessitate the development of resilient and high-yielding maize hybrids. Employing the line x tester method represents a promising approach to breed varieties tolerant to drought stress. This study aims to identify drought-tolerant maize hybrids derived from line x tester crosses. The research utilized a Randomized Complete Block Design (RCBD) with 40 genotypes replicated three times, totaling 120 experimental units. Drought stress was imposed following the CIMMYT method, wherein irrigation was provided at field capacity from 0 to 40 days after planting (DAP) at 10-day intervals, while drought stress commenced from 50 DAP until harvest. Under optimal conditions, irrigation occurred every 10 days until 80 DAP. Key observation parameters included plant height, days to 50% tasselling, harvest age, ear height, ear length, ear diameter, kernel weight per plant, 1000-kernel weight, and production per hectare. Results indicated several adaptive hybrid maize genotypes for both normal and drought conditions, as discerned by the Stress Tolerance Index (STI), including G2, G12, G13, G14, and G15. Moreover, hybrids G2, G18, G19, G21, and G24 exhibited notable drought tolerance based on the Stress Susceptibility Index (SSI). These findings underscore the potential of employing the line x tester method in breeding resilient maize hybrids tailored to mitigate the adverse impacts of drought stress, thereby fostering agricultural sustainability in resource-constrained environments like Madura Island.