1College of Agronomy and Biotechnology， Southwest University， Engineering Research Center of South Upland Agriculture， Ministry of Education， Chongqing 400716， China； 2International Nature Farming Research Center of Japan， Matsumoto 390-1401， Japan； 3Graduate Schools， Shinshu University， Matsumoto 390-8621， Japan
Abstract：In order to explore the effects of application of straw on crop growth and soil fertility in greenhouse vegetable cultivation，we designed 3 treatments as conventional tillage（ CK），straw mulch surface（ S） and straw buried into underground 20 cm deep（I）．The result showed that the S treatment could significantly improve the response of the blades to photosynthetically active radiation．In the early stage of crop growth，the biomass aboveground or underground of each treatment were r anked as S＞ I ＞CK．As time went by，I treatment presented a declining trend of yield．In I treatment，the total length of wheat root，root surface area，root volume，root diameter and leaf area were significantly lower than that in S treatment．S treatment sustainably improved the total soil carbon content，which was 41.87% higher than that of the initial value，2 months after sowing. In the initial wheat growing period， I and CK treatments were favorable for increasing the total carbon conte nt in soil．But，the total carbon content in soil started to decrease 2 months after sowing．In I treatment，it was 8.87% lower than the initial value.1 month after sowing the total nitrogen content in soil increased in I and CK treatments，while they were lower than the initial value 2 months later in 3 treatments．In a word，S treatment is beneficial for soil carbon storage as a result of higher carbon nitrogen ratio，which was significantly higher than the other 2 treatments.
