Study On Water Consumption Of Tomatoes Under Facility Planting

Taking tomatoes as the research object,the experiment was conducted in Solar Greenhouse of Tianjin Facility Agriculture High Efficiency and Water Saving Irrigation Demonstration and Extension Base in February 2018.The growth period of tomatoes under the condition of facility planting was divided into seedling stage,flowering and fruit setting stage,fruit harvesting stage,fruit harvesting peak stage and fruit harvesting end stage.Four irrigation water treatments were set up: full irrigation(CK)and irrigation.The underwater limits were 65%(T1),60%(T2)and 55%(T3)respectively.The small environmental factors of tomatoes planted in greenhouse were determined.The water consumption law and growth characteristics of tomatoes in different growth stages were studied.The relationship between water consumption and yield and water use efficiency was analyzed.The results can provide reference for the establishment of irrigation system for tomato and vegetable crops in facilities.The main results are as follows:(1)There are regular changes in indoor small environmental factor when tomatoes are planted in facilities.Temperature increases with the increase of solar radiation and reaches the highest temperature at 12-13.The average daily emperature rises during the whole growth and development period,and reaches a stable level at the peak of fruit picking.The average water consumption intensity at the stage is parabolic with the average temperature at the stage.The average daily humidity at theend of fruit harvest was only 60%-76%.(2)Under the condition of facility planting,when tomatoes were fully irrigated,the water consumption of tomatoes changed in stages,showing a trend of "increasedecrease-increase-decrease".In seedling stage,evaporation was dominant,and water consumption,water consumption intensity and water consumption modulus were the smallest;water consumption decreased slightly at the early stage of fruit picking;water consumption capacity of tomatoes was the strongest at the peak stage of fruit picking,with water consumption modulus of tomatoes being the largest;at the end,water consumption characteristics of tomatoes increased with the senescence of plants.(3)The water consumption of tomatoes decreases with the increase of water stress,and the average water consumption intensity at different stages is increasing with thedevelopment of time.The water consumption modulus of tomatoes under different trea tments is as follows: fruit picking peak period>flowering and fruit setting period >fruit picking initial period>fruit picking end period>seedling period.Water stress had little effect on water consumption characteristics of tomatoes at seedling stage.Water consumption,water consumption intensity and transpiration of tomatoes were greatly affected by water stress from flowering and fruit setting stage to fruit harvesting peak.Appropriate water stress(T1and T2 treatment)had a good promoting effect on the growth and development of tomatoes.The treatment with irrigation water limit of55% seriously inhibited the growth of tomatoes.(4)Water stress will affect the water consumption of tomato plants.The change of water consumption is evident in the growth characteristics of four organs: root,stem,leaf and fruit.Leaf growth traits and plant height decrease with the increase of water stress.Full irrigation will lead to plant growth,which is not conducive to squatting seedlings and fruit growth.The treatment with irrigation water limit of 65% is most conducive to the growth and development of roots and stems.The treatment with irrigation water limit of 75% has the least impact on the growth traits of tomat-oes.The treatment with irrigation water limit of55% severely inhibits the growth and development of tomatoes.(5)The relationship between tomato yield and water consumption is parabolic under greenhouse cultivation.When water consumption is 335 mm,tomato yield is the highest,54.37 t/hm2.The relationship between water use efficiency and water consumption of tomatoes is parabolic.When the water consumption is 285.5mm,the water use efficiency is the highest,and the corresponding yield is 51.43 t/hm2.When water consumption is285.5-335 mm,water saving and high yield can be achieved.The yield is 53.43 t/hm2-54.37t/hm2.