Infection and Expansion of Ginseng Roots and Leaves by Pseudomo-nas aeruginosa Labelled with GFPuv
To study the infection and expansion of Pseudomonas aeruginosa in roots and leaves of ginseng,strains PA2 and AT3 of P.aeruginosa with GFPuv labeled were constructed.The biological characteristics of the labeled strains were not significantly different from those of the original strains.When the strains were inoculated into the root of ginseng,the bacteria first colonized at the epidermis with wounds,cracks,and folds,and then gradually invaded to phloem and cambium.The infection rate,extension rate and pathogenicity of strain PA2-GFPuv isolated root were higher than those of the leaf source strain AT3-GFPuv.When inoculated in the petiole,the bacteria could extend from the main vein to the lateral vein and eventually spread to the leaf blade margin.The infection rate,ex-tension rate and pathogenicity of strain AT3-GFPuv isolated root were higher than those of the leaf source strain PA2-GFPuv.The number of bacteria colonized in the root of ginseng continued to in-crease at a lower initial amount,and that of PA2-GFPuv was higher than that of AT3-GFPuv.The number of bacteria colonized in the leaf of ginseng increased at first and then decreased,and that of AT3-GFPuv was higher than that of PA2-GFPuv.The number of colonies in the soil continued to de-crease at faster rate.P.aeruginosa strains expressing GFPuv gene can be used to directly observe in-fection and expansion of the bacteria in roots and leaves of ginseng.It provides a basis for further re-search about the infection and occurrence regularity of the disease.
万方数据
维普
