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Tomatos (Lycoperiscon esculentum) are attacked by many diseases and insect pestincluding fungi, bacteria, viruses, and nematodes.Ralstonia solanacearum, one of themost important phytopathogenic bacteria, causes lethal wilting diseases of more than 200plant species in 50 families.Control of bacterial wilt is more difficult due to thebacterium surviving freely in the soil for extended periods.As use of chemical pesticidehas been seriously questioned because of environmental and human health hazardbiological control of bacterial wilt nowadays is of paramount importance. The 4 isolates together with one biological product AN DI (Bacillus cereus) were testedfor their ability to promote growth and suppress the wilt pathogen in sterile and non-sterile soil under green house conditions.Bacterization of tomato seeds by the isolateswas found to be more effective in controlling the tomato wilt than treated seedling withthe biological product AN DI and non-treated control.The 4 isolates promoted plantgrowth measured by seed germination, plant height, fresh weight, dry weight and numberof fruits per plant.Likewise all isolates significantly reduced the percentage of infectionin sterile and non-sterile soil when compared with non-treated control.All isolatescolonized the root and stem of tomato plant endophytically.Brevibaciltus brevis B2 isnot only the best growth promoter but also the most efficient suppressor of the wiltinfection.This is the first record as biocontrol agent against bacterial diseases includingthe bacterial wilt.The biological product AN DI showed less effectiveness in growthpromotion and disease reduction. The effectiveness of three methods for delivery of the 4 Bacillus into tomato root, stemand leaves tissues was conducted in greenhouse conditions.The delivery methodsincluded seed treatment with soil drench, soil drench and foliar spray.Seed treatmentwith soil drench and soil drench methods of application led to establishment and recoveryof the endophytic bacteria from root tissues but not detected from roots with foliar spraymethod.The 4 endophytic bacteria were recovered from stem by the three deliverymethod except B8 which was not detected by foliar spray method.From the leaves all theisolates were detected by foliar spray method but only B2 and B7 were detected by seedtreatment with soil drench method and B2 only detected by soil drench method.The seedtreatment with soil drench was the most efficient method to deliver endophytic bacteriainto tomato tissues.All the 4 isolates in the three methods of application were enhancedthe growth of tomato and reduced wilt infection with varied degrees among the isolatesand methods of delivery.The results demonstrated that endophytic bacteria can berecovered from tomato tissues following inoculation by different methods described, butthe delivery efficacy varied with the methods and the endophytic bacteria isolate used. All the 4 isolates also showed antifungal activity against Fusarium oxysporum andPythium aphanidermatum in vitro.Antibiotic production of the 4 isolates was higher inCPM-Ca2+ medium than in CPG and CPM medium.The antibiotic metabolites in crudesupernatant were stable, which were not affected by Proteinase K and differentconcentration of pH level.The results revealed the presence of an extracellularthermostable and chloroform-soluble metabolite.High-performance liquidchromatography that absorbed light at 220 nm using C-18 column resulted in three peaksfor every isolate with antibiotic activity.These characteristics are similar to thosedescribed for cyclic antibiotic lipopeptides such as iturins.