Study On The Dry Matter Production Of Greenhouse Tomato And Its Response Of CO₂ Application

Tomato is one of the most important greenhouse crops. In order to explore the material distribution rule of greenhouse tomato and the response of CO₂ application, the cultivation experiment of greenhouse tomato was carried out in 2014 and 2015, in the solar greenhouse of Shanxi Agricultural University. In the cultivation experiment in 2015, the greenhouse was divided into three areas. As source gas, CO₂ were through into different areas at different rates. The rates were 5 L·min^-1,2.5 L·min^-1, no CO₂ fertilizer respectively. To further explore the impact of elevated CO₂ on tomato plant, the test in artificial climate chamber was carried out from July to September in 2015. Two treatments were set up, and the average CO₂ concentrations in the climate chambers were 515?L·L^-1,264 ?L·L^-1 respectively. The following results are drawn:1. The plant height, total leaf area, total leaf number and dry matter accumulation of greenhouse tomato were significantly associated with the days after planting. Average daily growth rate of plant height was 2.74 cm, and the rate of blade occurrence was 0.32 leaf·d^-1. Plant total leaf area increase about 70 ?cm?² a day, and dry matter were accumulated 9.4 g·dm^-2. Fruit dry weight and total dry weight of plant also had significant linear relationship, and about 69% of plant dry weight was assigned to the fruit. After CO₂ fertilization, the fruit diameter can increase by 20% than which of CK. Plant total accumulated dry matter after CO₂ treatment also presents obvious different. At the end of the treatments, plant dry matter increased by 51.1% compared with CK. Also, elevated CO₂ can increase the distribution rate of fruit.2. The dry matter accumulation of greenhouse tomato and effective accumulated temperature showed significant linear relationship, and under each effective accumulated temperature units ??·d?, the dry matter accumulation increased about 0.73 g·m^-2. In addition, combined with the relationship between fruit dry weight and plant dry weight, after about 161?·d effective accumulated temperature after planting, fruit began to bear. The relationship between the dry matter accumulation and photosynthetic active radiation in greenhouse was linearly related, and about 3.4 g dry matter was produced in the light of each MJ.3. Elevated CO₂ can increase the net photosynthesis rate by 100%, intercellular CO₂ concentration by 20 %, and chlorophyll content by 100% than Co. However, the stomatal conductance and transpiration rate decreased. Elevated CO₂ also significantly increased starch content in plant leaves, and improved vitamin C content, soluble sugar content, soluble solids content and sugar-acid ratio in tomato fruit, thus tomato flavor was improved.As concluded, the appropriate extension of the growth period can increase the matter accumulation ?including production, etc.?. Appling CO₂ in the greenhouse could further promote the material production of tomato, and promote the distribution of material to the fruit.