Isolation of Endophytic Bacteria From Mulberry and Screening of Beneficial Bacteria

229 endophytic bacteria strains were isolated from the tissues of different healthy mulberry varieties.The reasonable method for isolation of endophytic bacteria and purification was discussed, and the amount of endophytic bacteria was determined.The results showed that endophytic bacteria exist in all mulberry tissues including root,stem,leaf stalk,lamina and flower bud.But the population densities vary with varieties,tissues and growth periods of the plant.In vitro antagonistic examination revealed that in all 229 tested strains 42 strains(18.3%) showed antibiosis activities against Colletotrichum morifolium Hara,25 strains(10.9%) showed antibiosis activities against Aecidium mori(Bard) Diet and 8 strains showed strong inhibitory activities against some plant fungal pathogens,revealing potential in the aspect of antagonistic action.Bacteriological analysis showed that these 8 strains were belong to Bacillus sp.(G21,G49,Y12 and J26),Pseudomonas sp.(G82 and J50),Erwinia sp.(Y33)and Curtobacterium sp.(B19),respectively.