| In china, the obstacle in continuous cropping system has become a severe problem with the rapid development of intensive agriculture. The obstacles in continuous cropping system which may lead to the decrease of crop yield and high occurrence of root diseases is difficult to overcome because of the uncontrollable root growth condition under conventional soil management system. It is known to all that soilless culture is a good cropping method for its high yield and quality. Furthermore, it is a good way in settling the obstacle in continuous cropping system for its easy control of root growth environment. Unfortunately, soilless culture system has by far not been widely applied in China because of its high cost. Under such conditions, a new high yield cropping system of low cost which can perfectly settle the obstacle in continuous cropping system is in urgent need.The aim of our research is to establish such a cropping system. We name the cropping system in our research work the Controllable Nutrient Soil Management system( CNMS) . Due to its easy control of root growth environment, simple operation and low cost, the CNMS has the advantages of both soilless culture system and conventional soil management system. The results of our research work are as follows.1 The study on the effects of different sawdust concentration in the mixture of sawdust and soil treatment on cherry tomato plant growth was carried out in a greenhouse. There is evidence to show that the increase in sawdust concentration in the mixture of sawdust and soil can significantly increase the total porosity of the growth substrate. Sawdust addition can prevent soil from becoming harden, however, there is no significant difference in plant height, plant node number, leaf net photosynthesis, yield of perplant, and the quality of fruit between cherry tomato plant grown in each sawdust concentration treatment.2 Compare with the conventional soil management system, controllable nutrient soil management system has a drip irrigation system through which the nutrient solution can be evenly fertilized during tomato plant growth period. And this may lead to the even change in the pH and EC and the relative high water content of culture soil. Under such favorable root growth environment, the growth of tomato plants was sharply promoted. On 90th day after transplanting, The plant height and the area of the largest leaf of tomato plant grown in CNMS was significantly high than tomato plant grown in conventional soil management system. Especially, the total above ground dry weight was more than 34.8% high than conventional soil management treatment. Controllable nutrient soil management treatment has a impermeable plastic membrane which can prevent nutrient solution being percolated into field soil. Thus, the process of greenhouse soil salination was stopped. After the tomato plants was harvested, the EC of field soil under the CNMS culture trough was significantly lower than field soil in conventional soil management system.3 An anearobic treatment integrated with solarization process was established for soil disinfection in controllable soil management treatment system. The results of our research work showed that anearobic treatment integrated with solarization process can make a anearobic and hot environment in the relative closed system which may kill the pathogen of tomato bacterial wilt. Interestingly, The disease index, plant wilt percentage and browning index of vascular bundle of tomato plant grown in conventional soil management system with undisinfected soil reached 13.75%, 15% and 16.88% respectively while the values of all the items being studied above of tomato plant grown in controllable nutrient soil management system with disinfected soil were zero. To our surprise, there is no significant difference between the pH and EC of disinfected and undisinfected soil before 12 days anaerobic treatment and after 8days areobic treatment. And there is no prohibited effect on the growth of tomato plants grown in controllable nutri...
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