This study assessed the agronomic performance of seven maize hybrids cultivated under conventional tillage and supplementary irrigation (1,600 m³ ha⁻¹) in Cogealac, Constanța County, during the 2024–2025 growing season. Although irrigation partially compensated for water deficit, the season was marked by reduced rainfall and thermal stress, influencing vegetative growth and reproductive development. Plant density remained stable at harvest (mean 5.87 plants m⁻²), indicating good establishment under delayed sowing conditions. Thousand kernel weight showed limited variability (mean 300.1 g; CV = 2.72%), demonstrating relative stability of grain filling under irrigated conditions. Grain yield averaged 6,106 kg ha⁻¹, with a 19.5% difference between the highest- and lowest-performing hybrids. P88812, P9415, and Maxxatac II consistently exhibited superior biomass accumulation and grain conversion efficiency, exceeding the overall mean yield by 5–11%. The study aimed to evaluate the agronomic performance and adaptability of seven maize hybrids cultivated under the pedoclimatic conditions of Southeastern Romania and to identify the most suitable genetic material for maintaining stable productivity under climatic constraints. The experimental year was characterized by a pronounced precipitation deficit and episodes of high temperatures during flowering and grain filling, conditions that represented important limiting factors for maize development. Despite the application of supplementary irrigation, hybrid-specific responses were evident, highlighting significant differences in physiological adaptation and yield stability. The results confirm that irrigation alone cannot fully eliminate the negative effects of drought and heat stress. Hybrid genetic background, biomass production capacity, and assimilate partitioning efficiency remain decisive factors for achieving high and stable yields. These findings contribute to the identification of maize hybrids suitable for sustainable production systems and climate-resilient agricultural strategies in drought-prone areas of Southeastern Romania.

maize hybrids; irrigation efficiency; drought stress; grain yield; hybrid adaptability

agronomy

Presentation: poster