The Soil Microbial Activity And Microbial Functional Diversity Of Cotton Field In Northern Xinjiang Response To Organic Fertilizer Partial Substitution For Chemical Fertilizer

【Objective】In water-saving drip irrigation condition, The significance of chemical fertilizerof NPK fertigation combined with organic or biological organic fertilizer fertilization not onlymeeting crop nutrient requirements and improving nutrient utility efficiency, but alsoimproving soil physical and chemical properties of long-term drip irrigation cotton field,improving soil fertility and optimal regulating microflora and controling soil-borne disease ofhealthly soil. Long continnous cropping cotton field and excessive fertigation effecting soilpH and organic matter decreasing and microflora changing from "bacteria type" to "fungustype" effecting soil-borne disease take place frequently. Therefore, We studied the effecet ofcotton yield and soil biological properties on organic or bio-organic fertilizer PartialSubstitution for chemical fertilizer in the condition of field fertilization, we also studied themicrobial functional diversity and microflora of cotton field under precision fertilizationd.【Method】Under the condition of located fertilization, used microculture、enzymology andBiolog to study the number of soil functional bacteria(Bacteria, Fungi, Actinomycetes andPseudomonas)、antagonistic bacteria (Bacillus subtilis andTrichoderma viride) and pathogenicbacterium (Verticillum dahlia and Fusarium) and microbial biomass(C、N) response totreatments of NPK、organic-chemical and biological organic fertilizer in different growingperiod of cotton and different fertilized time, and used Biolog to research the soil microbialfunctional diversity response to treatments of organic-chemical fertilizer.【Result】1) Compared with CK, coventional fertilizing or treatments of different rates organicfertilizer combined with chemical fertilizer significantly increased (p<0.05) cotton yield, withchemical fertilizer or organic fertilizer supply, cotton yield could be reached to The sameyield level (4945~4978kg/hm~2), but there has no statistical difference among coventionalfertilizing and treatments of20%to40%chemical fertilize substituted by organic fertilizer.2) Organic fertilizer application significantly enhanced (p<0.05) soil enzyme activities,compared with coventional fertilizing, organic fertilizer application soil enzyme activities ofβ-glucosidase、dehydrogenase、fluorescein diacetate and alkaline phosphatase increased0.34~0.44、0.72~1.22、1.3~1.8and0.3~0.42times after treatment of organic or bio-organicfertilizer Partial Substitution for chemical fertilizer two years.3) The number of soil bacteria, actinomycetes as well as pseudomonas significantlyincreased with increasing organic fertilizer supply, but the number of soil fungi decreasedwith organic fertilizer rates increasing. The ratios of soil bacteria/fungi, soilactinomycetes/fungi and pseudomonas/fungi increased with the increasing the organicfertilizers application rates, but pseudomonas/bacteria ratio markedly reduced with CF ororganic fertilizer supply. 4) After two years of organic fertilizer partial substitution for chemical fertilizer, theantagonistic bacteria quantity(bacillus subtilis and trichoderma viride) more than theconventional fertilization treatment and the quantity of pathogenic bacteria (Verticilliumdahliae、Fusarium) is lower than conventional fertilization.5) Organic fertilizer partial substitution for chemical fertilizer can improve the microbialbiomass and decrease the ratio of microbial biomass C/microbial biomass N(MBC/MBN)6) Organic fertilizer partial substitution for chemical fertilizer improve the soil microbialAWCD and utilization of different carbon source, the diversity index, and has statisticaldifference among coventional fertilizing and treatments of20%to40%chemical fertilizesubstituted by organic fertilizer.【Conclusion】1) Under the condition of drop irrigation, Fertilized3000、6000kg/hm~2organic fertilizeror bio-organic fertilizer to replace20%~40%common fertilizer can meet the cotton regulargrowing and cotton yield could be reached up to the100%chemical fertilizer treatment.2) Organic fertilizer application significantly enhanced soil microorganisms activities.Compared with the treatment with100%CF supply, fertilized3000、6000kg/hm~2organicfertilizer or bio-organic fertilizer two years.soil enzyme activities of β-glucosidase anddehydrogenase increased by0.34~0.44、0.72~1.22times and also improved alkalinephosphatase、 fluorescein diacetate esterase activities. fertilized organic fertilizer orbio-organic fertilizer improved soil AWCD and Microbial biomass C and N, the treatment ofbio-organic fertilizer had the the most significant than others.3) fertilized organic fertilizer or bio-organic fertilizer made the composition of soilmicroorganism changed, the number of soil bacteria, actinomycetes as well as pseudomonassignificantly increased with increasing amendment rate of organic manure, but the number ofsoil fungi decreased with organic fertilizer rates increasing. The ratios of soil bacteria/fungi,actinomycetes/fungi and pseudomonas/fungi increased with increasing application rate oforganic manure, but pseudomonas/bacteria ratio and MBC/MBN markedly reduced in thetreatment with CF or organic fertilizer supply.4) fertilized organic fertilizer and bio-organic fertilizer improved the number of soilantagonistic bacteria and restrained the number of soil pathogenic bacteria, having thefunction in regulate and control soil microorganism composition of healthy soil.5) The soil microbial functional diversity expressed increasing species abundance、thenumber of common species and changed the capacity and kinds of substrate utilization of soilmicroorganisml.