Evaluation of Yield Stability and Regionalization of Hybrids under Different Agroecological Conditions in Republic of Serbia

This study presents the results of evaluating yield stability for seven maize hybrids (ZP 427, ZP 457, ZP 555, ZP 5601, ZP 606, ZP 6263, and ZP 707) conducted in 2020 and 2021, across nine distinct locations in Serbia. The aim of the research was to evaluate yield differences and stability between hybrids under varying agroecological conditions and to perform regionalization to optimize hybrid deployment in specific production areas. The experiment was carried out using a Randomized Complete Block Design (RCBD) with plots of 30 m² and three replications. The hybrids were tested across different maturity groups and analyzed in relation to planting density, harvested plant density, moisture content, and yield across four locations in Vojvodina and five in Central Serbia. The results showed that the average yield in Vojvodina was 9.20 t/ha, while the average yield in Central Serbia was lower at 8.54 t/ha. The hybrid ZP 5601 achieved the highest average yield in both regions (9.43 t/ha) with good stability under various ecological conditions. Similarly, ZP 6263 reached an average yield of 9.28 t/ha, demonstrating better adaptation to favorable conditions. On the other hand, ZP 606, despite yielding lower (8.96 t/ha), exhibited exceptional stability, making it suitable for production environments with higher variability. Analysis of yield stability using the Francis, Kannenberg, and Eberhart & Russell methods showed that ZP 5601 had the lowest coefficient of variation (CV = 31.8%), while ZP 606 had the lowest S2di (109039.8), making it the most stable hybrid across different locations. The hybrids ZP 427 and ZP 457 exhibited the highest variability (CV = 34.6% and 36.1%, respectively), with ZP 427 showing the lowest stability (S2di = 525656.0). Based on these findings, ZP 457, ZP 5601 and ZP 6263 are recommended for intensive production, ZP 427 and ZP 606 for less favorable environments.