Effect Of Rotating Different Leaf Vegetables With Tomato During Winter Fallow Season Under Plastic Tunnel On Reuse Of Continuose Cropping Organic Substrate

The experiment was designed to know the allelopathic effects of three different vegetables on the growth and production of tomato crop by crop rotation system in substrate culture. Tomato cv'Gold shed No 1'was selected as test material, however, garlic, no-heading Chinese cabbage and leaf lettuce were rotated with two continuous cropping seasons continuous tomato under plastic tunnel substrate cultivation. The matrix formula was rice husk, corncob and regardless of slag with a ratio of 5:2:3 (volume ratio). We worked on the tomato yield, quality, nutrient uptake and distribution, its root reductive strength after rotation of different leafy vegetables in greenhouse, and analysed the matrix physical and chemical properties. We also studdied the matrix activity and different growth stages of the matrix, the number of microbial species and the process of change and nutrient release of cultivation during rotation around leafy vegetables.The aim of this experiment was to explore the different culture medium for tomato, leaf rotation of biological disinfection effect, and to provide theoretical and technical basis of the matrix re-use and also overcoming the continuous cropping obstacles. The main results of this study achieved as the following:(1) Except for the obvious change in EC value for the substrate of continuous cropping treatment, there is little alteration in EC value, pH value, bulk density and total porosity in the substrates of the other treatments before and after crop cultivation. It concluded that all the substrates are relatively stable in physical and chemical qualities which are all within the optimal range for tomato growing and are appropriate for reuse to grow tomato crop.(2) It showed that rotating with garlic, no-heading Chinese cabbage and leaf lecture significantly increased the number of microorganism i.e bacteria and ratio of bacteria and fungus in substrate. However, the number of fungus decreased. Besides, relatively higher level of sucrase, urease, alkaline phosphatase and catalase activity in the substrate were recorded in all the rotating treatments. Among the three leaf vegetables, garlic showed the best rotating effect on microorganism group and enzyme activity of substrate, yield and root vigor of the afterculture tomato during the whole growth season. In conclusion, rotating with garlic in substrate improved the microorganism environment, increased the enzyme activity and rehabilitated the obstacle of continuous cropping of tomato.(3) During the whole growth period, the uptake of nutrients of tomato in the treatment rotation with garlic was highest. At the end of experiment, the content of K in the fruit was the highest. The contents of N, P, K in different organs in treatment rotation with garlic were the highest followed by the rotation cabbage processing, however the continuous tomato is the worst.(4) Throughout the growing season of tomato, the rotation with garlic and cabbage are better in plant height and stem diameter, and continuous tomato is the worst deal.The fresh weight of the tomato ground part, underground parts and root shoot ratio are the largest in the rotation of garlic treatment, and with the new allocation matrix (CK2) was not significant. By different leaf crop rotation tomato, root reductive strength is the largest by rotation with garlic, followed by the rotation cabbage processing and the continuous cropping is the poorest.(5) Different leafy vegetables crop rotation with tomato changed yield and quality of fruit, the experiment after rotated with garlic, the fruit quality, the content of soluble sugar, soluble protein, lycopene and sugar-acid ratio of tomato are significantly increased. To a certain extent that improve the nutritional quality of tomato fruit.(6) In different cultivation systems, the economic returns of rotation with garlic-tomato is largest followed by the rotation with Chinese cabbage–tomato and the rotation with leaf lettuce–tomato.In summary, tomato crop rotation effect with different leaf vegetable by organic matrix cultivation, rotation with garlic performed the best followed by rotation with cabbage, but continuous treatment severely reduces yield and quality of tomato. Therefore, it can be considered that tomato rotation with garlic in organic matrix can overcome continuous cropping obstacles and obtained the organic matrix efficient sustainable production in greenhouse.