Community Structure Analysis And Strain Resources Mining Of Imidacloprid-degrading Consortium

In order to control the large-scale outbreak of cotton aphid and other pests caused by cotton continuous cropping in Xinjiang,imidacloprid and other pesticides have been widely used for a long time.Imidacloprid not only can eliminate agricultural pests and improve agricultural production efficiency,but also has a harmful effect on agricultural production,which ultimately harms human health and ecological environment pollution.Therefore,how to eliminate the harm caused by imidacloprid and how to use imidacloprid pesticide effectively is one of the hot spots.In order to obtain the microbial resources suitable for the degradation of Imidacloprid in the local climate and soil environment.After imidacloprid was used as the sole carbon source to enrich and degrade BCLfrom cotton continuous cropping soil in Xinjiang for a long time,its structure and composition were identified by high-throughput sequencing,and bacterial resources were extracted from BCL by using a variety of conventional media and the media designed by high-throughput sequencing results.At the taxonomic level,BCL is mainly composed of Proteobacteria(67.05%),actinobacteria(10.67%),Firmicutes(9.99%),chlorofeli(4.1%),acidobacteria(2.84%);at the taxonomic level,Pseudomonas(16.33%),Moraxella(11.14%),Eschericia(4.57%),Brochothrix(2.19%),etc.,accounting for 58.13%.48 strains,such as BP2,BP5,BP8,BG5,BG7,BG17,BGW8,were isolated from the conventional culture medium such as the lowest salt.They are respectively subordinated to shinella,nocardioids,agroyces,sphingopyxis,bacillus,cellosimicrobium and bosea.25 strains of BMV3,BMV 5,BMV 7.1,BMV 14.1,BLE1,BLE3.1,BLE4,BLE5,BLE10.1 were isolated by trace element solution and vitamin solution.They are Paenibacillus,ammoniphilus,Planococcus,brevibacillius,Paenibacillus,bacillus,sphingopyxis,Rhodococcus,nocardioids and so on.The homology of BP5 and nocardioids nitrophenolicus NSP 41 was 98.08%,that of BMV4.1 and novosphingobium hasiacum w-51 was 96.56%,that of BMV5 and ammoniphilus Resina cc-rt-e was 98.5%,that of BLE7 and nitratireducer inductor c115 was 97.86%,and that of other strains was 98.29-100%.It can be seen that there are some unclassified strains in the BCL from the soil of Xinjiang cotton region.According to the results of high-throughput sequencing,some low abundance bacteria can be specifically isolated from the culture medium.In the study of degradation ability of bacteria and isolates,the degradation ability of bacteria without adding nitrogen source was lower than that of imidacloprid without adding 1% nitrogen source for 7 days,14 days and 21 days,respectively.The degradation ability was relatively stable at the 7th day.The degradation capacity of the bacteria group with 1% nitrogen source reached 14.99% on the 21 st day.In the study of the degradation ability of the isolate,the degradation rate of BMV4.1(novosphingobium)increased regularly with the increase of time,and the degradation rate of BMV4.1 reached 23.06% on the 14 th day.With the increase of time,the degradation rate of imidacloprid increased regularly.The degradation rate of BMV5(Novosphingobium)was 15.45% on the 21 st day.BLE7(Nitratireductor)had no significant effect on the degradation rate of Imidacloprid with the increase of time.The degradation rate was detected from the 7th to the 21 th day of culture.In this study,the isolation of microbial resources in Xinjiang special environment can also lay a foundation for bioremediation of soil pesticide pollution.