The Effects of Metarhizium anisopliae and Beauveria bassiana on the Soil Cultivable Microbial Community of Aq-uilaria sinensis
To investigate the effects of applying biocontrol agents on the cultivable microorganisms in the rhizosphere and rhizo-plane soil of plants,Aquilaria sinensis was used as the experimental material.Through methods such as irrigation with bio-control agent suspensions and microbial isolation and cultivation,this study examined the impact of Metarhizium anisopliae and Beauveria bassiana on the diversity and community structure changes of cultivable soil microorganisms associated with A.sinensis.The results showed that the survival activity of M.anisopliae in the soil was higher than that of B.bassiana.Af-ter 7 days of cultivation,the population density of M.anisopliae peaked,reaching 539.002×104 and 776.041 ×104 colony-forming units(CFU)/g in the rhizosphere and root zone,respectively,and then gradually declined,maintaining a low lev-el in subsequent periods.Similarly,the population density of B.bassiana showed a downward trend,but the rate of decline was slower compared to M.anisopliae,with population densities of 0.299×104 and 1.071×104 CFU/g in the rhizosphere and root zone,respectively,after 35 days of cultivation.The application of biocontrol agents had different effects on soil fungi,bacteria,and actinomycetes.M.anisopliae significantly increased the number of actinomycetes in the rhizosphere and root zone,achieving 2.53 and 1.90 times the control group values after 35 days,respectively.In contrast,B.bassiana reduced the number of fungi in the rhizosphere,with a quantity that was 30.62％of the control group after 35 days,and al-so decreased the numbers of fungi,bacteria,and actinomycetes in the root zone.After treatment with M.anisopliae,the to-tal microbial quantity in the rhizosphere increased in the short term,reaching 1.15 times that of the control group at 14 days,while the total microbial quantity in the root zone decreased.Treatment with B.bassiana led to a slow decline in the total cultivable microbial quantity,which was 82.76％and 61.37％of the control group in the rhizosphere and root zone,respectively,after 35 days.In summary,both M.anisopliae and B.bassiana had significant effects on the microbial com-munity structure and population dynamics in the rhizosphere and root zone of A.sinensis,with the effects on cultivable soil microbial communities varying depending on the type of biocontrol agent used.
Aquilaria sinensisMetarhizium anisopliaeBeauveria bassianaSoilMicrobial community
万方数据
维普
