Multi-Year Evaluation of Silage Yield, Quality, and Stability in Maize (Zea mays L.) Genotypes under Black Sea Conditions

Maize (Zea mays L.) is the primary crop used in modern livestock systems for silage production due to its high biomass yield, energy density, and favorable fermentation characteristics. Developing silage maize genotypes with improved adaptation capacity is essential for ensuring consistent, high-quality, and sustainable silage outputs. This study was conducted over four consecutive years (2017–2020) under the ecological conditions of Samsun, Türkiye, and evaluated 16 silage maize genotypes for a broad set of morphological, yield, and quality traits. The assessed parameters included days to flowering, plant height (cm), ear height (cm), leaf–stem ratio (%), ear–plant ratio (%), green herbage yield (t/da), dry matter yield (t/da), dry matter content (%), crude protein (%), neutral detergent fiber (NDF, %), acid detergent fiber (ADF, %), acid detergent lignin (ADL, %), cellulose, ash content (%), oil content (%), as well as milk yield (t/ha), gross energy (Mcal/kg DM), and digestible energy (Mcal/kg DM). Despite considerable environmental variability across years, several genotypes consistently exhibited superior performance for multiple traits. Notably, genotype TTM 2015-8 excelled in quality and energy-related attributes, TTM 2016-40 was distinguished by its high dry matter yield, and TTM 2015-22 showed remarkable green herbage productivity. Overall, the findings highlight the critical role of genotype selection in optimizing both environmental adaptation and combined yield–quality performance in silage maize.