秸秆降解菌的筛选及其特征分析

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中图分类号：S642.2 文献标志码：A 文章编号：1673-2871（2025）11-105-09

Abstract：Inordertoscrenoutthemicrobialagentsthateficientlyandrapidlydegradestraw，andprovideatheoretical basisforthefertilizationofstrawretumingtothefield.ThedominantstrainXJ-132wasscreenedfrom16Ostraw-degrading bacteria byenrichmentculture.TheantagonismofXJ-132strainandthe mechanismof plant growth-promoting action oncucumber（Jinyan No.4）were studiedbymeasuring thesecretionandcelulaseactivityofXJ-132 strain，as wellas its resistance to plant pathogensand seed germination.Theresults showed that the degradation rateof rice straw was 58.00% after35days of liquid fermentationofXJ-132strain，which could significantly promote thedegradationof rice straw.Bymeasuring thecelluase productionabilityofthe strain，it was foundthatthe hemicellulaseandcellulase activitiesof strainXJ-132 increased firstandthen decreased with theextensionofculture time.The maximumactivitiesof hemicellulase， endo-β-1，4-glucanase，exon-β-1，4-glucanase and β glucosidasewere32.53，329.68，493.55and 4.90U⋅mL-1 ， respectively.BacterialinfectionexperimentsshowedthatXJ-32strainhadacertainihibitoryefectonsoil-bornediseases， and had the best inhibitory effect on Fusarium wilt of banana， with a bacterium inhibition rate of 49.30% . The homology of 16s rDNA sequence analysis showed that XJ-132 strain had 99.93% homology with Bacillus subtilis.Furtheranalysis was carriedout thatthe secreted materialcompositionofXJ-132 strain included the productionofsiderophoreand indoleaceticacid，andhadtheabilitytoproduceammoniaandHCN.Inaddition，thelowoncentrationofXJ-132strainfermentation broth hadapromoting efectonseed germination，comparedwith CK，whentheconcentrationofthebacterialiquid was 108CFU⋅mL-1 ，the seed germination rate increased significantly by 4.66 percentage points.In conclusion，strain XJ-132 hadhighcelllase activity，whichcould notonlyrapidlydegraderice straw，butalsohadgoodantibacterialability， and could promoteseedgermination.Through the isolation，screening and identificationof straw-degradingbacteria， this paper provides a theoretical basis for the fullutilization of straw resources in China.

KeyWords：Cucumber; Celulosedegradation;Strawdegrading bacteria;Antagonistic bacteria; Seed germination

农作物秸秆降解能增加土壤有机质含量，改善土壤理化性质，提高土壤微生物种群丰度[1-2]。（剩余11708字）