Effects Of Continuous Cropping Of Processed Tomato On Its Growth And Biological Activity

Processing tomato is one of the important cash crops in Xin Jiang province China. The concentration of plant area and expending of plant area produced a series of adverse impact on its growth process. The autoxin is main factor to cause continuous obstacle has been reported on many study. The pot and lattice experiment were conducted to explore effect of continuous mono-cropping and addition activated charcoal to soil on the growth and physicochemical properties and the microflora and enzyme activities of processed tomato soil. Those changes in a certain extent reflect the quality and integrity of the soil. The purpose was to open out the physiological mechanism of continuous obstacle and the effect of the quality of soil, lay the theory basis for conquering the obstacle of continuous cropping on processed tomato production, especially with regard to assess the autotoxicity effects of continuous cropping by addition of activated charcoal in soil.1. The effect of continuous cropping of processed tomato on its growth and physicochemical properties. With increasing cropping years, the activity of superoxide dismutase (SOD), chlorophyll content and root vigor decreased, peroxidase (POD) declined after increasing, but malondialdehyde (MDA) content was enhanced. Net photosynthetic rate (Pn), stomatal conductance (Gs) and Transpiration rate (Tr) decreased respectively with increasing year of cropping, the most effect on continuous cropping for 4years, the Pn, Gs and Tr decreased to 58.7%, 45.8% and 55.1% than control (1-year), respectively, but Intercellular Ci were intensified, was 1.30 times of 1 year. After adding activated charcoal to soil, the plant height and stem thick and biomass was enhanced, and the index of physiology witch include the SOD activity and chlorophyll and root vigor were increased than their control, while MDA content declined. The effect of continuous cropping on photosynthesis were that Pn increased by 219.4% and 236.9%respectively,under cropping for 3-years and 4-years, Gs were increased by 169.7%and 106.6%, Tr was 2.32 and 2.62 times of their control, Wue was 1.37and 1.29 times of their control, but Ci were pressed by 28.7%and 35.9%.Those showed that autotoxicity effects were alleviated through the active carbon's absorbing to autoxin.2. Continuous mono-cropping affected the microbial for processed tomato to some extent. Bacteria was main group on soil, followed by actinomycete, the fungi was least. With the increasing cropping years, the total of microbial and bacteria number were decreased by 12.1% and 16.8%and 12.land 16.8% respectively under cropping for 2-years and 3-years than control (1-year). While the numbers of fungi and actinomycete increased, the number of fungi were increased by 20% and 60%, the number of actinomycete were 1.04 times and 1.12 times of 1-year. it shows that the microbial transfer to fungi with the continuous cropping. With continuous cropping years, The number of beneficial bacteria which were Nitrobacteria and Aerobic azotobacter and Aerobic cellulose bacterium and Anaerobic cellulose bacterium were decreased, but Antisulphate reducer were enhanced, which were adverse bacteria, the trends of Denitrobacteria number was first increase and then decrease. With adding activated charcoal to soil, the number of bacteria increased 5.8% and 1.6% respectively at 2-year and 3-year, while the numbers of actinomycetes and fungi decreased 13.0% and 23.1% and 8.3% and 50%, respectively. The vary of functionality bacterial were the number of nitrobacteria and Aerobic azotobacter and Aerobic cellulose bacterium were increased, Antisulphate reducer was declined, Anaerobic azotobacter and Aerobic cellulose bacterium were enhanced at 2 cropping years, but Denitrobacteria number was declined at 2-years, then enhancing. In processed tomato soil, the Denitrobacteria were predominant group, followed by the group of nitrobacteria and Antisulphate reducer and azotobacter, cellulose bacterium number were the least.3 The prominent effect of continuous cropping on the enzyme activities of processed tomato. Continuous mono-cropping affected the microbial and enzyme activities for processed tomato to some extent. With increasing cropping years, Catalase activity increased, and Urase,Saccharase,Polyhenol oxidase and Phosphatase activities decreased, of which the Saccharase activity have most effect, which decreased by 28.2%and 43.7% under cropping for 2-years and 3-years,respectely. After adding activated charcoal to soil, activities of Urase, Invertase, Phosphatase and Polyhenol oxidase were higher than control (without activated charcoal addition), but Catalase activity decreased, the bigger effect expressed on Polyhenol oxidase, increased by 31.8% under cropping for 3-years.4 The enzyme activities have close relations with microbial. Urase activities have negative relation with fungi and actinomycete, Saccharase activity have negative relation with actinomycete and have positive relation with bacteria and Aerobic cellulose bacterium and nitrobacteria. The activity of Polyhenol oxidase have prominent relation, which was positive relation. Catalase activity have positive relation with fungi and actinomycete and have negative relation with bacterium and nitrobacteria and Anaerobic cellulose bacterium. Phosphatase activity have significant positive relation with Antisulphate reducer and Aerobic azotobacter, of which reach to significant level with Aerobic azotobacter, but the relation with actinomycete was reversed, The Sulfureted hydrogen oxidant number have slightly relation with enzyme activities on the soil...