Effect of Genotype × Season Interaction on Yield and Quality Traits in Hybrid and Standard Summer Squash (Cucurbita pepo L.) Cultivars

Background: Climate change has become a crucial factor affecting the timing and success of vegetable cultivation, especially in regions like the eastern Mediterranean where temperature and precipitation patterns are shifting. Summer squash (Cucurbita pepo L.), typically grown in warm seasons, is an important export crop in the Mersin province of Turkey. However, few studies have examined its performance under different seasonal conditions. Methods: This study aimed to compare the yield and fruit quality traits of five hybrid (Alba F1, Amelthee F1, Hadra F1, Hürrem F1, Vildan F1) and five standard (Pelin, Nazlı (S), Black Squash Elite, Eskenderany, White Bush) summer squash cultivars grown in spring and autumn. The experiment was conducted under open-field conditions in Tarsus, Mersin in 2022 using a randomized plot design. Key yield parameters (fruit weight, fruit length, fruit diameter, number of fruits per plant, total yield) and quality traits (fruit flesh hardness, water-soluble dry matter, fresh and dry fruit weights) were evaluated using two-way ANOVA. Result: Spring cultivation produced significantly higher yields (2595.12 g/plant) than autumn (635.51 g/plant), due to more favorable environmental conditions. ‘Vildan F1’ had the highest yield in both seasons, while ‘Hadra F1’ and ‘Pelin’ were notable for fruit firmness and size. Although spring cultivation remains advantageous, autumn conditions increased dry matter content, suggesting potential benefits under future warming. These findings underline the importance of cultivar selection and seasonal planning for sustainable squash production and export continuity amid climate change.