Effect Of Different Temperature And Light On Tomato Growth, Photosynthesis, Yield And Quality In The Greenhouse

Temperature and light intensity are the necessary conditions of plant growth and development. The lack of temperature and light intensity often hinders the production, quality and economic efficiency from increasing in out-of-season vegetable cultivation process. Based on the results of previous studies, this research, choosing tomato"Jinpeng No.1"as material, studied the effect of different temperature(by heating or ventilating) and light intensity(by filling light) on tomato growth, photosynthesis, yield and quality in the greenhouse with potted cultivation. The main results are as follows:1 With the increased of temperature and light intensity, the plant height, stem diameter, leaf growth, fresh weight of shoot and root, accumulation of dry matter of tomato all increased. In the CK temperature, the 3 ~ 4℃and 6 ~ 7℃higher than CK temperature, the tomato growth rate and root to shoot ratio(R/T) decreased as the extension of time; on 50th day of treating, the relative growth rate of plant height, stem diameter of temperature treatment were significantly much less than that of CK temperature as the increasing of light intensity, and the plant was also older. So it was indicated that the plant grew faster under sub-high temperature for a short time, but would aged earlier for a long time.2 With the increase of temperature, the content of Chlorophyll a and Chlorophyll b of tomato leaves increased, a /b ratio decreased, the content leaf Pro significantly decreased; under the same temperature, as increase of light intensity, the content of Chlorophyll a and Chlorophyll b decreased, while the a / b ratio, Pro content, root activity increased; but the content of leaf Pro of CK temperature was higher than that of temperature treatment, besides, root activity didn't vary apparently in the earlier stage of treating, but increased fast in the later stage.3 As the increase of light intensity, the tomato leaf net photosynthetic rate (Pn) increased, L3> L2> L1, while the intercellular CO2 concentration decreased; under the same light intensity, with the increase of temperature, Pn and intercellular CO2 concentration increased. The tomato Pn is the highest at 25-30℃, but decreased as the increased beyond 30℃. With the increase of temperature and light intensity, stomatal conductance and transpiration rate showed an increasing trend, however, no significant difference between treatments; the intercellular CO2 concentration reduced, showed a significant difference in the flowering, fruit setting and fruit enlarging stage under different temperature and light levels.4 As the increase of temperature, the tomato fruit developing fast in early time maturing earlier, but the average weight of fruit and total output dropped significantly. Under the same temperature, with the increase fill light intensity, tomato fruit weight, yield increased, vitamin C of the fruit, soluble sugar, soluble solids and sugar acid ratio increased, organic acid content decreased. As the increase of temperature and light intensity, fruit sugar acid ratio decreased. This experiment showed that under temperature 26.6℃and light intensity of 395μmol/(m2?s), the yield was the highest and the quality of tomato fruit was the best.