The present study aimed to investigate the effects of low temperature on the growth, yield, quality, and biologically active compounds of strawberry and obtain basic information for developing a technology for stable growth of strawberry in greenhouses. Growth of strawberry, including leaf number, area, and length, plant height, and dry weight was better at the optimum growth temperature of 20℃ than at a lower temperature of 15°C. At the low temperature of 15°C, the cultivar 'Maehyang' was more tolerant and displayed better growth rate than 'Seolhyang'. At 15°C, the fruit production per week and fruit weight was lower than that at 20°C. In contrast, fruit length and diameter were not significantly different between the two growth temperatures. Growth temperature also did not affect the fruit color index, Hunter L, a, b value, or fruit firmness. However, the sugar content of strawberries grown at 15 was higher by 0.8 and 1.5 Brix for 'Seolhyang' and 'Maehyang', respectively, than of those grown at 20°C. There was no difference in the content of fisetin, a biologically active compound, for 'Seolhyang' at both growth temperatures, however, the fisetin content of 'Maehyang' was higher at 20°C than at 15 . Cinchonine and ellagic acid content of 'Seolhyang' was higher at 20°C than at 15 , whereas that of 'Maehyang' was higher at 15°C than at 20℃ . Quercetin content showed no significant differences with respect to growth temperature, however, it tended to increase at 20°C. The cinnamic acid content of 'Seolhyang' was higher at 15°C than at 20℃ , whereas that of 'Maehyang' increased at 20°C. Collectively, the biologically active compounds of strawberry were affected by growth temperature. Moreover, the content of these compounds tended to increase at 20°C, the optimum growth temperature, rather than at the sub-optimal growth temperature of 15°C.

Growth and physiological disorders caused by abnormally low temperatures were evaluated in pepper, an important field crop in Korea. In addition, the effects of chemical treatment using glutamine was verified on minimizing the damages by low temperature. The growth of pepper plants in stem length and diameter was suppressed as the temperature decreased from 25℃, and the suppression level was the highest for plants grown for 90 days at 20℃. However, root growth was not affected by the different temperatures. The number of leaf and leaf area decreased at the temperatures below 25C, an optimum temperature for growth. Fresh weight and dry weight decreased for plants grown at 20℃. Pepper fruit yield also decreased by 11% at 20℃ in comparison to 25℃. Falling blossom rate was different depending on the growth temperature, and the rate was 27.2% at 25℃, 35.2% at 22.5℃, and 41.0% at 20℃, indicating that falling blossom rate increased as temperature decreased. Different growth temperatures did not affected on the level of symptom of calcium deficiency and Phytopathora blight. Falling blossom was severe at abnormally low temperature of 20℃, but the treatment of glutamine reduced falling blossom rate and increased the yield by 7.0% as compared to control. The optimum concentration of glutamine treatment was 10 mg/L for yields.