The Effect Of Chitosan On Vegetables Yield And Quality, Root Growth And Soil Physicochemistry Properties

The pot, root box and solution cultivation were conducted to study the effects of chitosan on vegetables yields, qualities, root growth. soil physical properties and chemical characteristics. The resuilts show that:1. Chitosan treatment can increas vegetables yields. Application of chitosan increased the yield of cherry tomato, tomato, and Chinese cabbagge by 16. 2%—20.0%, 24.6%-26.1%, and 3.6%-29.4%, separately.2. Chitosan application improved qualities of vegetables. Application of chitosan increased the Vc content and the brix/acid ratio in vegetables. The pot cultivation showed that fertilizer-chitosan treatment increased content of Vc, brix/acid ratio and decreased NO₃-N concent in Chinese cabbage. The solution cultivation also showed that application of 2mg/L chitosan increased concent of Vc and brix/acid ratio in Chinese cabbage by 3.1% and 25.5%, separately, but decreased concent of NO₃-N by 26.6%.3. Chitosan treatment can improve vegetables growth. Chitosan treatment improved growth of vegetable shoot, especially seedling growth. The growth speed of plant height of tomato by using chitosan was two times than control before the flowering period in cherry tomato and tomato, the stem was thicker than control, the content of chlorophyll was increased significantly, the number of flower and fruit were more than control, and the date of maturity was advanced two or three days.4. Chitosan application inproved the root growth, increased the active absorption area and the ratio of root-shoot. The solution cultural cultivation indicated that Chitosan application increased the length and weight of root and the ratio of root-shoot, and the effects were greater at 2mg/L chitosan concent. But when the chitosan concent was too high, the root growth was inhibited. Chitosan also increased the root-shoot ratio of the five vegetables: tomato, cucumber, Chinese cabbage, amaranth and pepper in root box cultivation, the root-shoot ratio of five vegetables were increased 15%-60%; their root density were also increased, especially in tomato and cucumber.5. Chitoan treatment can amend soil physical properties. Application of chitoan improved the total porosity in yellow brown soil and flavor-aquic soil. It also increased the soil capillary porosity, especially in the condition of planting vegetables. The ability of holding water and the bigger diameter micro-aggregate were enhanced, but decreased content of the smaller diameter.6. Chitosan facilitated the decomposition of soil organic matter. Chitosan facilitated the decomposition of soil organic matter. For no planting soil, the effects of chitosan were related with soil species. Chitosan faciliated the decomposition of organic matte in yellow brown soil, but increased the organic content in flavor-aquic soil.7. Chitosan elevated available nutrition contents in soil and faeiliated nutrition absorption by vegetable. Chitosan increased the available N content in no planting soil. Compared with the control, fertilizer-chitosan treatment significantly increased alkali hydrolysable N in both yellow brown soil and flavor-aquic soils. The content of alkali hydrolysable N also was increased in planting soil with small biomass and bulk soil with in root box culture. But the content of alkali hydrolysable N also was reduced in planting soil and rhizosphere soil in root box culture. The nutrition contents of vegetable were increased. The change trend of soil available P was consistent with alkali hydrolysable N, but its range was smaller. The available K contents in soil, with or without fertilizer, were elevated in the two soils treated with chitosan. But for the planting soil, the content of available K was reduced. We concluded that chitosan improved soil available nutrient content, faciliated vegetable takeup of nutrients, and improved soil fertility and fertilizer efficiency8. Chitosan treatment can enhance vegetable resistance. Chitosan increased the content of praline in tomato leaves, and decreased the content of MDA and EL. Praline concent in cherry tomato was significantly increased with chitosan application. Chitosan also increased praline content in cabbage leaves, and decreased the MDA content, improving cold-resistance of Chinese cabbage.