Stress metabolite accumulation, bacterial growth and bacterial immobilization during host and nonhost responses of soybean to bacteria

摘要: Abstract Hypersensitive response inducing (HR-inducing) strains of the heterologous (non-soybean) pathogens Pseudomonas syringae pv. phaseolicola and P. attained populations in soybean leaves only three-fold to five-fold less than a compatible race pathogen glycinea. Incompatible races glycinea non-HR-inducing strain Corynebacterium flaccumfaciens showed more restricted growth. A Erwinia carotovora subsp. atroseptica saprophyte Bacillus cereus did not grow leaves. pseudomonads induced accumulation isoflavonoids (daicizein, formononetin, genistein, glyceollin) isoflavone glucosides (daidzin, genistin, ononin). alone, C. E. astroseplica induce either type stress metabolite. Of purified compounds tested, glyceollin alone had significant antibacterial activity, but against Cram-positive bacteria. By use vitro bioassays, no evidence was obtained indicate that induction additional inhibitory or activity due total isoflavonoid content inoculated leaf tissue responsible for resistance. Immobilization bacteria by highly electron-dense material intercellular spaces occurred greatest extent with B. cereus, lesser flaccumfaciens. No bacterial immobilization evident at 48 h after inoculation incompatible pseudomonads.