Effects Of Water And Nitrogen Coupling On Matter Production And Nitrogen Absorption And Allocation Of Tomato

Tomato is one of the most important crops in the cultivation of vegetables in our country.To understand the rregulation of crop growth and development,dry matter production and allocation,and nitrogen uptake and allocation of tomato,and to improve crop yield,dry matter production and water and nitrogen use efficiency by applying the reasonable amount of nitrogen fertilizer and water irrigation,the pot experiment of nitrogen(nitrogen application of per plant of per time were:N1:0.05g,N2:0.2g)and water(the exact irrigation of per plant of per time were:W1:600mL,W2:750mL,W3:900mL)coupling was conducted and tomato cultivar 'Hongzungui' was selected as the material.The 4 leaves seedlings were planted in the nutrition bowls(Model 30 cm×28 cm,with moss peat as media)for 6 treatments,each with 40 pots and replicated 4 times for total of 960 plants.The experiment was from Apr.17 to Aug.3,2017 for 109 days,results are as follows:1.Applying nitrogenous fertilizer will significantly increase the water use efficiency and plant dry matter and nitrogen content in organs of the plant,and improve the nutritional indicators of the fruit,thereby improving the fruit quality.Compared with N1,it was increased by 7%and 6%of plant height and leaf number under N2 level,respectively,and the total dry matter of the plant increased by 27%,the difference is extremely significant,which promoted the reproductive growth of the plant,it was increased significantly by 41%and 36%of the fruit number and dry weight of fruit,and increasing the fruit's contents of soluble sugar,VC and soluble solids.The final nitrogen content(27 g/kg)of plants increased by 50%compared to N1(18 g/kg)at N2 level,which increased the total nitrogen uptake by 90%.During the whole growth cycle of plants,the nitrogen content in roots,stems and leaves increased first and then decreased,and the nitrogen content in the early stage of fruit setting was the highest.The changes of nitrogen content in stem is the most sensitive in all organs of plant.2.Appropriate amount of irrigation can increase the fruit yield,total biomass,and nitrogen use efficiency.Compared with W1,it was increased by 5%,10%and 7%of plant height,stem diameter,and leaf number under W3 level,respectively.It was increased by 24%of the total dry matter of the plant,so that it was increased by 20%of the plant nitrogen use efficiency.Therefor promoted the reproductive growth of the plant,and it was increased by 9%and 20%of the fruit number and dry weight of fruit,the difference is significant.The plant of W2 also grows better than W1.Water treatment had no significant effect on the nitrogen content of the organs,and the difference of cumulative nitrogen uptake was mainly caused by differences in the dry matter of the plants.3.The coupling of water and nitrogen also has a significant effect on plant growth.Compared with N1 W1,it was increased by 23%,10%,and 13%of the plant height,stem diameter,and leaf number under N2W3,respectively,and it was increased by 57%of the total dry matter of plants.This promoted reproductive growth of plant,and it was increased by 57%of the fruit number,so that dry weight of fruit increased by 62%.And combination of low nitrogen and low water can promote the allocation of nitrogen into fruit,and combination of high nitrogen and high water is beneficial to the allocation of nitrogen in to stem and leave.The conclusion showed,in this experiment,the combination of high nitrogen and high water(average nitrogen application and irrigation volume of 0.057 g and 352 mL per day and per plant)obtained a best results with total dry matter weight of 135 g per plant(810 g.m-2)and fruit dry matter of 73 g per plant(438 g.m 2)in a 109 day planting period.And the final nitrogen content in all organs of the plant was at a relatively high level,and the total nitrogen uptake(3.48 g per plant)was the highest.The quantitative indicators provide a basis for the comprehensive management of water and fertilizers for efficient greenhouse tomato production,and have important guiding significance for the application of tomato water and fertilizer integration technology.