INDUCTION OF MISTAKES OF CONTACT RECOGNITION AS RELATED TO HOST INDUCED RESISTANCE IN TOBACCO BROWN SPOT
接触识别导误与烟草抗赤星病诱导的关系

On leaf surfaces of tobacco which had been pretreated respectively withnopathogenic bacteria, virus, and hypovirulent strains of brown spot pathogen(Alternaria alternata), virulent strain of A. alternata showed 7 types of mistakes ofpreinfection behaviors: (1) delayed germination of spore; (2) continuous sporulation;(3) reduced or defective production of adhesin; (4) germ tube growth away from leafsurfaces; (5) swollen tip part of germ tube with defective or reduced infection; (6) tightanchoring of germ tube on leaf surfaces, with defective or reduced infection, and (7)zigzag germ tuber, vasculated or emptied tip part of germ tube. The induced mistakeswere related to decrease in pathogenicity of the pathogen, indicating by 55%-94%reduction of brown spot in the induced tobacco. It was suggested that the mistakeinduction is the expression of mistake induction of the host-pathogen contactrecognition and contributes to induced resistance of tobacco to brown spot.