Abstract: High temperature is one of the common agricultural meteorological disasters, affecting the growth and development of crops. In order to study the effect of high temperature at the seedling stage on the leaf area index and dry matter production of strawberry in the facility, the strawberry variety " Benihoppe " was used as the experimental material.Different dynamic high temperatures (32/22℃, 35/25℃, 38/28℃ and 41/41℃; maximum daily temperature/minimum daily temperature) and different stress days (2d, 5d, 8d and 11d) were performed on the strawberry seedlings in greenhouses in 2018 and 2019, with 28/18℃ as a control. The seedlings were then transplanted to a Venlo glass greenhouse for normal cultivation experiment. The data of 2018 were used to quantitatively analyze the effects of high temperature and stress days on the leaf area index, maximum photosynthetic rate and dry matter production of strawberry seedlings. Models of strawberry leaf area index, maximum photosynthetic rate and dry matter production were then constructed based on the physiological development time. The models were finally verified with the experimental data of 2019. The results showed that the R2 between the simulated and measured values of strawberry leaf area index, maximum photosynthesis rate, and dry matter production model was 0.98, 0.83, and 0.91, respectively, the root mean square errors(RMSE) were 0.04, 1.50μmol·m⁻²·s⁻¹ and 1.38g·m^–2, and the relative errors(RE) were 6.43%, 13.17% and 11.49%, respectively. The established model was able to simulate the effects of extreme high temperature at seedling stage on strawberry leaf area index and dry matter production in greenhouses. The research results would provide a theoretical basis for the management and regulation of the high-temperature environment of strawberries in the greenhouse.

Key words: Strawberry, Short term high temperature at seedling stage, Physiological development time, Leaf area, Maximum photosynthetic rate, Dry matter production, Simulation model