In vivo and in vitro antibacterial activity of neomycin against plant pathogenic bacteria

摘要

The purpose of this study was to evaluate thepotentialof neomycinto suppress the development of economically important plant pathogenic bacteria. Thein vitroantibacterial activity againstXanthomonas campestrispv. citri,Erwinia carotovorasubsp. carotovora,Xanthomonas oryzaepv.oryzaeandRalstonia solanacearumwas evaluated.The minimal inhibitory concentration values for the four strains were 2, 0.5, 0.25 and 2 mg l-1, respectively, and minimal bactericidal concentration values were 4, 2, 0.25 and 8 mg l-1, respectively. Furthermore, this effect of neomycin on the cell morphology ofXanthomonas oryzaepv.oryzaewas investigated bytransmission electron microscope, and it indicated thatneomycin caused damage to bacteria, resulting in the leakage of cytoplasmic contents.Finally, the effects of neomycin on disease development and spread were determined using potted plants in the greenhouse.In vitrostudies indicated that post-infectional spraying with neomycin significantly inhibited the development of citrus bacterial canker caused byX. campestrispv. citri, cabbage soft rot caused byE. carotovorasubsp. carotovora, ginger bacterial wilt caused byR. solanacearumand rice bacterial blight caused byX. oryzae pv.oryzae(80.51, 77.55, 77.54 and 69.07% disease reduction, respectively).