Exploration Of Induced Systemic Resistance Of Tomato To Botrytis Cinerea By Endogenous Bacillus Licheniformis TG116

The tomato grey mold caused by Botrytis cinerea is one of the important plant diseases in greenhouse tomato produce.It might frequently create ruinous harm to greenhouse vegetables in particularly tomato.Endophytic Bacillus licheniformis is an important biological control bacteria which play an important role in biocontrolling plant disease. A mass of researches indicate that the prevention mechanisms of Endophytic Bacillus licheniformis have diversity, which exert biocontrol against phytopathogens not only by secreting antibacterial proteins, bacteriolysis and competition,but also by the mechanism of induced systemic resistance of plants.The purpose of this research is mainly study whether Strain TG116,bacterial suspensions and bacteria-free suspension are induced to produce systemic resistance of tomato or not,conditions,physiological and biochemical mechanisms.The research aimed to reveal the mechanism of induced systemic resistance(ISR) preliminary.In this experiment, I selected the strains TG116 which were kept in our laboratory with a broad spectrum of antagonistic. This experiment had been on a pot by adopting spatial segregation between strain TG116 and Botrytis cinerea.Results suggested that disease index of tomato grey mold was decreased after inoculation with TG116,which indicated that TG116 could induce systemic resistance and improve resistance of tomato gray mold.Five key factors were choosed,which influence the control effects,to explore the control effects including induction substance, inoculation volume, induction concentration, induction methods and interval time for the induced systemic resistance. Based on single-factor experiments, I applied on Response Surface Methods to analysis and determine the conditions of optimal control effects:inoculation volume was 10 mL/plant,induction concentration was 6×108 CFU/mL,inoculated strain TG116 by root irrigation,challenging inoculated Botrytis cinerea after three days.under the conditions above,the effect of induced systemic resistance can acheive 53.6%.To probe into physiological and biochemical mechanism of ISR,the activity of polyphenol oxidase(PPO), phenylalanine(PAL), peroxidase(POD), Superoxide dismutase(SOD), Catalase(CAT), ?-1,3-glucanase, Chitinase and maleicdialdehye(MDA) of tomato were characterized after being inoculated with TG116.Results suggest that after inoculation of tomato roots with TG116,activities of POD,PPO,PAL,SOD and CAT in cucumber leaves were increased;Especially after inoculated Botrytis cinerea, the ascensional range of five kinds of defense enzymes' s activity is higher than that of single inoculation;Meanwhile the content of MDA which can reduce the plant cell membrane lipid peroxidation damage was decreased in tomatoes leaves after being inoculated TG116; Although TG116 treatment didn't directly resulted in elevating for the activities of 1,3-glucanase and chitinase,its induced treatment had some effect on promoting,maintaining,and stabilizing the activities of ?-1,3-glucanase and chitinase in infected plants.My results suggest that Strain TG116 could induce tomato to produce ISR.