柠条堆肥与枯草杆菌对黄瓜连作土壤修复作用机理研究

According to continuous cucumber cropping soil microbial obstacles was increasingly outstanding, soil sustainable utilization was restrained in Ningxia, prominent replant disease cucumber soil was used as material in this project. The cultivation mode was that fallowed in the summer, grown traditional early spring and autumn winter seasons cucumber. According to amount of traditional fertilization, pot experiment of different application amounts of caragana microphylla compost was designed, and two factor field experiment was disigned, one factor was levels of nitrogen fertilizer, and the other was application of bacillus subtilis. Three levels of nitrogen fertilizer were designed, which were the nitrogen content of caragana microphylla compost was equal nitrogen amount with traditional fertilization, the nitrogen content of caragana microphylla compost was 75％ nitrogen amount with traditional fertilization, and the nitrogen content of caragana microphylla compost was 50％ nitrogen amount with traditional fertilization. In this project fixed-point test was used to research the plant growth,soil nutrient cycling, soil microbial community dynamic change, and to analysis the correlation between these indices and cucumber yield. Through the analysis of results to determine the reasonable application amounts of caragana microphylla compost, and to determine the contribution of caragana microphylla compost to supply of nitrogen and reducing nitrogen input. The purpose of the project was to provide a theoretical basis for exploring restoraton mechanism of interaction between caragana microphylla compost and bacsllus subtilis on continuous cucumber cropping soil microbial obstacles, and achieving cucumber soil sustainable production.

针对宁夏设施黄瓜连作土壤微生物学障碍日益突出，土壤可持续利用受到抑制的问题，以温室连作障碍突出的黄瓜土壤为研究对象，在不改变传统两茬黄瓜，夏季休闲的种植模式基础上，针对传统施肥，设计柠条堆肥不同施用量的的盆栽试验，以及3个氮素水平（传统底肥100％等效氮素含量的柠条堆肥、传统底肥75％等效氮素含量的柠条堆肥、传统底肥50％等效氮素含量的柠条堆肥）和枯草杆菌的双因素田间定位试验，系统研究各处理下植株生长、土壤养分循环、微生物群落的动态演变规律，评价各指标与作物生产力间的关系，明确柠条堆肥的合理施用量以及其对减少氮素投入和满足作物生长的氮素供应能力，明确堆肥与枯草杆菌作用下黄瓜连作土壤微生物学障碍的修复机理，为实现设施黄瓜土壤可持续利用提供依据。

针对宁夏设施黄瓜连作土壤呈碱性，微生物学障碍日益突出，土壤可持续利用受到抑制问题，以连作10年设施黄瓜连作土壤为研究对象，研究蜡样芽孢杆菌对土壤质量修复效果和对作物生长的影响，并研究柠条堆肥不同氮素替代量与枯草杆菌对连作土壤微生物学障碍的修复，以及对减少氮素投入提高氮素利用率的贡献，并探究柠条堆肥与酸性土壤调理剂对土壤质量的改良效果。结果表明，1)蜡样芽孢杆菌(Bacillus cereus 20亿CFU/g) 800g/667m2可显著促进植株根系生长，有效提高植株的光合作用，改善果实品质，提高黄瓜产量，调节土壤生态环境，改善土壤质量。2)柠条堆肥（CM）可用作黄瓜生产中传统鸡粪的替代品。在定植前作为基肥应用不会降低作物产量，CM施用和BC接种互作下作物产量和NUE均与土壤性质变化和土壤微生物对碳源的利用能力密切相关，接种蜡状芽孢杆菌（BC）可在CM-N输入减少的条件下提高作物产量，柠条堆肥和蜡状芽孢杆菌联合施用可减少氮素输入但提高氮素利用效率（NUE）。3）酸性土壤改良剂与柠条堆肥同时施用可有效降低土壤pH，增加土壤EC；在土壤养分、土壤酶活性、微生物数量方面，改良剂与柠条堆肥联合施用优于单一柠条堆肥施用，传统鸡粪50%氮素量柠条堆肥与改良剂处理土壤养分含量显著优于其它处理，改善土壤质量、改善果实品质最显著。本项目明确了不同氮素水平柠条堆肥施用下土壤碳氮矿化过程，以及对减少土壤氮素投入，均衡连作土壤养分、微生物区系，修复连作土壤微生物障碍的修复机理，揭示了枯草杆菌与柠条堆肥对阻控连作土壤微生物学障碍的互作效应，为设施黄瓜的土壤可持续利用提供依据。