轮作和有机肥对连作小白菜生长及土壤微生物特性的影响

为研究轮作和有机肥处理对连作土壤的修复作用,以小白菜(Brassica campestris L.ssp.chinensis Makino var.communis Tsen et Lee)连作土壤为对照,比较玉米轮作,玉米秸秆还田,玉米秸秆有机肥等对连作土壤酶活性、微生物活性、活性有机碳含量及小白菜光合速率、根系活力、根系生长的影响。结果表明,轮作和有机肥处理不同程度地增加了连作小白菜光合速率、干物重、根系活力和根系ATPase活性,降低了根系MDA含量,同时提高了连作土壤酸性磷酸酶、脲酶、转化酶活性和微生物对碳源的利用能力,其中长期轮作及施用发酵有机肥的促进作用较大。相关分析表明,土壤酶活性、根系活力、活性有机碳含量、碳源利用AWCD值之间存在极显著正相关关系,说明采用合适的有机肥投入方式可以缓解连作对作物生长造成的抑制。

Effects of Rotation and Organic Fertilizer on the Growth of Brassica campestris ssp. chinensis var. communis and Soil Microbial Characteristics of Continuous Cropping Soil

In order to study the effect of rotation and organic ferti1izer treatment on the soi1 of continuous cropping, we take the continuous Brassica campestris L. ssp. chinensis Makino var. communis Tsen et Lee cropping soi1 as the contro1,compared the effects of maize rotation,corn straw,corn straw organic ferti1izer on the growth of B. campestris ssp. chinensis var. commu-nis and microbia1 characteristics under continuous cropping soi1. Soi1 enzyme activities, microbia1 activity, active organic car-bon content and B. campestris ssp. chinensis var. communis photosynthetic rate, root activity, root growth effect were exam-ined. The resu1ts show that the rotation and manure increased cropping cabbage photosynthetic rate, dry matter weight, root activity and root ATPase activity, reduced the MDA content of root, and improved the continuous cropping soi1 acid phos-phatase, urease,invertase, carbon source uti1ization abi1ity of microbe. Rotation with 1onger time and fermented organic ferti1-izer had better effects compared to the other treatment. Corre1ation ana1ysis showed that there was a significant positive corre-1ation between soi1 enzyme activity, root activity, MBC and AWCD va1ue. It is showed that the inhibition of continuous crop-ping on crop growth can be a11eviated by means of proper organic ferti1izer input.