本试验在温室盆栽条件下研究阴沟肠杆菌JP6菌株对烟株生长及植烟土壤养分、酶活和细菌群落多样性的影响.试验设计两个处理:对照组每株施用5 mL培养基,处理组每株施用5 mL JP6液体菌剂.研究结果显示:与对照相比,施用JP6菌株30 d的烟株株高极显著增加23.89%,最大叶表面积显著增加13.63%;施用JP6菌株60 d的烟株株高显著增加8.55%;采收后,JP6处理的茎和叶全氮、全磷含量显著增加;与对照相比,JP6处理的土壤中全氮、速效钾减少7.69%和12.77%;有效磷和有机质含量分别提高3.45%、11.95%;土壤过氧化氢酶、蔗糖酶、中性磷酸酶、酸性磷酸酶活性分别增加21.15%、39.25%、23.9%、15.2%.Illumina MiSeq高通量测序分析发现,施用JP6菌株影响了土壤细菌群落多样性,施用JP6和对照的烟株根际土壤中细菌种类分别为4297±92和4420±179个OTUs;施用JP6的烟株根际土壤中可比对出的特有细菌有17种,CK特有的细菌有5种;与对照相比,JP6的根际土壤中有11个与解磷相关的菌属相对丰度高于CK,其中固氮菌属(Azotobacter)、微小杆菌属(Exiguobacterium)为JP6组特有.研究表明,阴沟肠杆菌JP6菌株对烟株的生长具有促进作用,同时也能够改变土壤酶活性,引起根际土壤细菌菌群结构的变化,提高解磷/溶磷菌属的相对丰度.对JP6菌株在农业上的实际应用具有指导意义.
This study was aimed to research the effects of Enterobacter cloacae strain JP6 on the growth of tobacco plant, soil nutrient,enzyme activity and diversity of bacterial community under greenhouse potted conditions.Two treatments were designed: the control group was treated with 5 mL medium per plant, and the treatment group was treated with 5 mL JP6 liquid bacteria.The results showed that compared with the control group,the tobacco plant strain with 30 d of JP6 strain was significantly increased by 23.89%, and the maximum leaf surface area increased by 13.63%.The plant height of tobacco treated with JP6 for 60 days increased significantly by 8.55%;After harvest,the contents of stem and leaf total nitrogen and total phosphorus in JP6 were significantly increased.Compared with the control,the total nitrogen and available potassium in the soil treated by JP6 were reduced by 7.69% and 12.77%. The contents of available phosphorus and organic matter increased by 3.45% and 11.95% respectively.The activities of catalase,sucrase,neutral phosphatase and acid phosphatase in soil increased by 21.15%, 39.25%, 23.9% and 15.2% respectively. Illumina MiSeq high-throughput sequencing analysis showed that the application of JP6 strain affected the diversity of soil bacterial community.The bacterial species in tobacco rhizosphere soil treated with JP6 and control were 4297 ±92 and 4420 ±179 OTUs, respectively. There are 17 species of endemic bacteria in tobacco rhizosphere soil treated with JP6 application,and there were 5 bacteria in CK.Compared with the control,there were 11 bacteria relative abundance in the rhizosphere soil of JP6 than CK,among which Azotobacter and Exiguo bacterium were unique to JP6 group.The results showed that the E. cloacae strain JP6 can promote the growth of tobacco,change the soil enzyme activity and bacterial flora structure in rhizosphere soil,and increase the relative abundance of phosphate-dissolving bacteria.It is of guiding significance for the practical application of JP6 strains in agriculture.