Study On The Promoting And Disease Resistance Of Three Forage Endophytes And Rhizosphere Microorganisms

Endophytes and rhizosphere microorganisms can produce functional metabolites,provide a source of nutrition for the host,and improve the disease resistance and stress resistance.Elymus sibiricus L.cv.‘chuancao No.2',Roegneria stricta Keng cv.“chuanxi”,Elynus nutans Griseb.cv.Aba chinensis are three kinds of excellent new varieties of forage.In this study,the three forages were used as research materials.Analyze the three forage rhizosphere microorganisms and endophytes,the cultivable method was used to isolate 173 strains,including 22 fungi and 151 bacteria.The evaluation results of resistance to wheat scab and growth promotion of each strain showed that 4 strains of fungi and 61 strains of bacteria can produce indoleacetic acid(IAA)in a concentration range of 0.02-14.75 mg/L,and the maximum yield of strain PJ81 was 14.75 mg/L;There are 8 strains of fungi and 93 strains of bacteria that can produce GA3 with a concentration range of 11.03-468.91 mg / L,of which the highest yield of PJ119 is 468.91 mg/L;9 fungi and 85 strains have the qualitative detection of Siderophore;5 fungi and 77 bacteria can degrade cellulose.Different strains showed different inhibition effect on Fusarium graminearum,the range is: 43.35%-82.76%.The comprehensive analysis of the ability to isolate each strain showed that the strains PJ22,PJ68,PJ73,and PJ81 all have antimicrobial and promote activity.Among the fungal strains,none of them had these five capabilities concurrently,but PJ161 has the highest qualitative detection of IAA among the fungal strains at 8.76 mg/L,and t PJ112 has the highest qualitative detection of GA3 among fungal strains at 285.55 mg/L.According to morphological and molecular identification,4 bacterial belong to 2 genera,namely,Propionibacterium,Bacillus Cohn.PJ22 and PJ68 belong to Bacillus Cohn,and PJ73 and PJ81 belong to Propionibacterium.PJ112 and PJ161 belong to Penicillium.The combination of rhizosphere strains PJ81 and PJ22 was used as bacterial ?;the strains PJ81,PJ22,PJ68,and PJ73 were combined as Microbial ?;the combination of endophytes PJ73 and PJ68 was Microbial ?;the combination of endophytic fungi PJ112 and PJ161 was Microbial ?.A pot experiment was carried out.The results of measuring the physiological indicators of the three forages showed that under the treatment,the results showed that the plant height,Leaf length,leaf width,leaf color,leaf number,root length,main root length,main root number,side root number,and above-ground dry weight and root dry weight all had varying degrees of increase.A comprehensive comparison of the effects found that the best promotion(P <0.05)of the three forages was the Microbial ?.The compound Microbial ? had the best promotion effect on three kinds of forages.The leaves of forages treated with Microbial ? were less prone to yellowing than other treatment groups.Compared with the CK,Microbial ? increased the plant heights of Elymus sibiricus L.cv.‘chuancao No.2',Roegneria stricta Keng cv.“chuanxi”,and Elynus nutans Griseb.cv.Aba by 19.7 cm,21.12 cm,13.23 cm;Leaf length increased by 2.1 cm,9.4 cm,6.44 cm;leaf width increased by 2.03 mm,1.39 mm,0.55 mm;leaf number increased by 2.33,0.67,0.00;main root number increased by 8.33,8.83,3.33;side root Number increased by 200,110.83,151.33;main root length increased by 5.05 cm,4.38 cm,3.32 cm;root length increased by 9.20 cm,9.88 cm,4.95 cm;above ground dry weight increased by 130.90 mg,127.40 mg,96.10 mg;root dry weight increased by 27.50 mg,13.50 mg,24.20 mg.The results of the evaluation of the inhibitory effect showed that each compound bacterial agent can reduce the susceptibility to forage grass,and the compound bacterium ? had the best disease suppression effect compared with other treatment groups.The inhibitory rates of Elymus sibiricus L.cv.‘chuancao No.2'and Roegneria stricta Keng cv.“chuanxi” were treated with bacterial ? and reached 80% and 90%. Respectively.A comprehensive investigation of the effects of inoculants on the growth promotion and disease resistance of forages should that the inoculum growth promotion and disease resistance effects of Microbial 1(PJ81 + PJ22)were significantly higher than those of other treatments.The bactericide can be used as a bacterial growth promoter for forage and a biocontrol agent against wheat scab pathogen,and provides a certain basis for the use of microbial bactericides in the treatment of degraded grasslands.The growth-promoting and disease-resistant effects further studied.