| In China, the agicultural straw resources are abundant, which make the biggest annual yields among the world. But the utilization ratio and efficiency is quite low, as large amount of straw resouces are burned or discharged indiscriminatingly, and little is utilized after technical treatment. Tomato is the main crop variety of vegetables cultivated in controlled environment in China, but as a result of the unfavorable cultivation media and management techniques, the yields and quality is quite low. With corn and wheat straw used as materials, the utilizing methods of agricultural straw on vegetable cultivation in controlled environment were studied, and the fertilization and watering management techniques were also studied during tomato long-season cultivation with the straw substrate as the cultivation media. Main research results were as follows:Corn and wheat straw substrates were abundant in nutrient elements, the content of macro N, P, K and available P, K in mixed substrates were significantly higher than in peat, especially the macro and available K content, and main heavy metal contents in straw substrates were allowed according to relevant criterion. Straw substrate exhibited the disadvantage of relative smaller bulk density and bigger A/W ration, and the imperfect property could be improved by mixing with other heavy substrate materials such as soil and slag with the ratio of 3:1. Compared with the mixed substrate of peat and vermiculite, the mixed substrate of straw and soil raised the Pn and yields of tomato significantly in a greenhouse tomato production system. The physical properties of straw substrate changed significantly after the cultivation experiment due to the persistent degradation of straw, and obvious shrinkage of substrate was found, so it's quite necessary to take feasible measure to reduce the influence on rhizosphere environment and crop growing according to different cultivation modes.
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