Leaf Photosynthesis Characteristics of Seven Japanese Strawberry Cultivars Grown in a Greenhouse

Many strawberry cultivars are developed in Japan each year; however, the characterization of each cultivar, including yield, is insufficient. As they may affect strawberry yield, leaf photosynthesis characteristics were determined for seven Japanese strawberry cultivars (‘Akihime’, ‘Benihoppe’, ‘Ibarakiss’, ‘Oi C berry’, ‘Sachinoka’, ‘Suzuakane’, and ‘Yotsuboshi’) and evaluated with reference to a C₃ photosynthesis model. Plants were grown hydroponically with a substrate-filled elevated-bed system in a glass greenhouse. Leaf gas-exchange rates were assessed at different photosynthetic photon fluxes and CO₂ partial pressures using full-expanded leaves of plants 130–150 days after transplanting (DAT). We found that the net photosynthetic rate (Pn) was higher in ‘Yotsuboshi’ and ‘Sachinoka’ than in other cultivars both under light-limited and light-saturated conditions. The difference in Pn was correlated with stomatal conductance (gs), irrespective of light conditions. We also measured leaf Pn under both CO₂-limited and CO₂-saturated conditions; however, there were only a slight differences in either capacity of ribulose-1,5-bisphosphate carboxylation or regeneration among cultivars. Our results suggest that a difference in gs contributed to variations in leaf Pn among Japanese strawberry cultivars.