The Effect Of Brevibacterium Frigoritolerans And Bacillus Megaterium In The Invasion Of Flaveria Bidentis

Flaveria bidentis(L.)Kuntze.is an ecologically hazardous Asteraceae invasion plant.F.bidentis can accumulate functional bacteria that are beneficial to itself and promote its growth through allelochemicals,either directly or indirectly.Bacillus is a kind of plant rhizosphere growth promoting bacteria(PGPR),which plays a vital role in plant growth.In this experiment,two dominant Bacillus species,Brevibacterium frigoritolerans and Bacillus megaterium,accumulated in the invading plant F.bidentis rhizosphere soil,were used as the research object.In order to explore the functional activities and mechanism of Bacillus in the invasive process of F.bidentis,we determined the phosphate and potassium solubilizing ability,the inhibition rate on three pathogenic bacteria and the effect on plant growth.The results were as follows:1.The phosphate solubilizing ability and the inhibition rate on Fusarium vasinfectum of B.frigoritolerans strains in the rhizosphere soil of F.bidentis were stronger than Setaria viridis.The phosphate solubilizing ability of B.megaterium strains in the rhizosphere soil of F.bidentis were weaker than S.viridis,but the inhibition rate on three pathogens(Fusarium vasinfectum,Rhizoctonia solani,Verticillium dahliae)were strong than S.viridis.The result showed that F.bidentis could enhance P content and restrain pathogens by accumulating Bacillus.2.B.frigoritolerans promoted the growth of F.bidentis and S.viridis.The root extraction solution of F.bidentis inhibited the growth of S.viridis,but after added the B.frigoritolerans,the biomass of S.viridis increased significantly.The result showed that the B.frigoritolerans may weaken the allelopathy of F.bidentis and provided a new idea for biological control of F.bidentis.