Interactive Effects of Temperature on Seed Germination Percentage in Selected Eggplant (Solanum melongena L.) Cultivars

Eggplant (Solanum melongena L.) is a thermophilic vegetable species, and its cultivation in temperate climate regions typically begins with seedling production in protected environments such as greenhouses. Temperature plays a crucial role in the seed germination process, and optimal thermal conditions must be maintained to ensure successful emergence. Scientific literature recommends constant temperature ranges between 25 ± 1–2°C and 27 ± 1–3°C during germination. This study aimed to evaluate the influence of temperature on eggplant seed germination by assessing variations in germination percentage and timing under controlled greenhouse conditions. Three commonly cultivated eggplant hybrids in southern Romania—Barcelona, Habana, and Black Pearl—were subjected to two constant temperature regimes: 23°C and 28°C. The results revealed significant differences in both germination percentage and germination time, defined as the period required to reach 85% germination and the peak germination moment. The highest performance was observed in the Black Pearl hybrid at 28°C, which achieved a germination rate of 98%. These findings underscore temperature as a determining factor in eggplant seed germination, and highlights the substantial variations in germination and emergence parameters across temperature conditions. Overall, the results support the importance of maintaining optimal thermal conditions in seedling production and suggest the need for further research to optimize germination strategies for different eggplant hybrids under varying environmental conditions.