Study On Growth Characteristics And Water Demand Of Tomato Grown In Different Cultivation Seasons In Solar Greenhouse

Water plays significant role in growth and development,as well as fruit yield and quality of plant.To ascertain water requirement of crop is the basis for formulating scientific and rational irrigation system.In this experiment,growth characteristics and water requirements of tomato（Lycopersicon esculentum Mill.）grown in winter-spring and autumn-winter seasons were investigated by using pot and border cultivation,the relationship between water demand and environmental conditions and plant growth and development were analyzed.,and the water demand models were established.The main results are as follows:1.In the winter-spring season,with the advancement of tomato growth period,the light intensity in the solar greenhouse enhances,the temperature increases and the relative air humidity lowers,while the opposite is true in autumn-winter season.And the stem diameter,leaf area,leaf area index,root activity,photosynthetic characteristics,yield and quality of tomato in winter-spring season are significantly better than those in autumn-winter season.The per hectare yield of pot cultivation tomato and border cultivation tomato in winter-spring season increased by 12.45%and 20.63%,respectively,compared with autumn-winter season.2.The variation curve of daily water requirement of tomato plants in winter-spring season is similar to that in autumn-winter season,which shows the regularity of less in the early stage,more in the middle stage and decreasing in the later stage.However,the water requirement peak of winter-spring crop in the third ear fruit color changing stage.And the pot and border cultivation tomoto are 3.53 mm·d^-11 and 6.70 mm·d^-1,respectively,while the water requirement peak of autumn-winter crop appeares in the 3rd⁴th panicle flower opening stage.And the pot and border cultivation are 1.79 mm·d^-11 and 3.34 mm·d^-1,respectively.The water requirement of pot cultivation tomato and border cultivation tomato in autumn-winter season is 33.85%and 40.70%lower than that in winter-spring season,respectively.The growth factors,including leaf area index and fresh weight,are the main factors related to the daily water requirement during the whole growth period of winter-spring crop,while the autumn-winter crop is the environmental factor,including daily cumulative light intensity and humidity.3.The regression models of daily water requirement of tomato in winter-spring crop and autumn-winter crop are established respectively,and the fitting effect is better.Path analysis showed that the main decision-making factor affecting the water requirement of tomato in winter-spring season is the leaf area index.The decision coefficients of pot and border cultivation tomoto are 0.769 and 0.701,respectively.While the main decision-making factor affecting the water requirement of tomato in autumn-winter season is the daily average light intensity.The decision coefficients of pot and border cultivation tomoto are 0.495 and 0.355,respectively.