Research On Pectinase Change Rule In Different Wax Gourd Lines Under The Fusarium Stress

Plant cell wall is an important place for wax gourd-Fusarium oxysporum interaction.The pectinase and pectin polysaccharide is the main component of plant cell walls.Oncethe plant was suffered by the pathogen, the structure of pectinase activity and pectinpolysaccharides of Plant cell wall will change.The specific role of pectinase and pectinpolysaccharides on plant defense pathogen process remains unclear.In this study, two wax gourd (Benincasa hispida Cogn.) lines (fusarium wilt resistantand susceptible, respectively) was used as the material after being inoculated with withnon-cuting root uninoculation、cuting root uninoculation、cutting root inoculation treatment. Studythree kinds of important pectinase were compared research after inoculation,At the sametime to get more information about individual HG epitopes involved in waxgourd-Fusarium interaction, we performed a systematic immunofluorescence andimmuno-dot study with10monoclonal antibodies recognizing pectic epitopes with diverseDM. To reveal the process of the pectinase wax gourd-Fusarium oxysporum interactionmechanism.Provide a theoretical basis for the anti-Fusarium wilt wax gourd breeding anddisease control.The main results are as follows:1. Changes in the activities in pectinases（1）The susceptible lines respectively24h,48h,72h non-cut root uninoculation of PGactivity was higher than the resistant lines; But after cut root uninoculation, Thesusceptible lines of PG activity was lower than the resistant lines; After cutting the rootinoculation treatment, The susceptible lines of PG activity still lower than the the resistantlines.（2）The susceptible lines respectively, in24h,48h,72h non-cut root uninoculation ofPMG activity was higher than the resistant lines;After cut root uninoculation, the PMGactivity was still higher than the activity of resistant lines;But after cutting the rootinoculation treatment,the PMG activity was lower than the resistant lines.（3）The susceptible lines respectively24h,48h,72h non-cut root uninoculation of PMEactivity was lower than the resistant lines. After cut root uninoculation, the PME activitywas still lower than the activity of resistant lines. But after cutting the root inoculationtreatment,the PME activity was lower than the resistant lines.2. The spatial distribution of HG with different DM.（1）No detectabe signal could be observed with antibodies LM7in wax gourd root. Thesignal of CCRC-M34and CCRC-M130in both cultivars before and after pathogeninoculation was not strong. The eiptope level of2F4antibody in the control plants of bothcultivar was also low. However, an obvious increase was observed after pathogeninoculation in both cultivars except72h after treatment in the susceptible cultivar.（2）The JIM5epitope levels in the resistant cultivar both before and after pathogen inoculation were higher than those in the susceptible one while the CCRC-M38antibodywas just on the opposite. The JIM7epitope levels in the susceptible cultivar beforepathogen inoculation was also higher than that in the resistant one. However, pathogeninoculation resulted in more increase in the resistant cultivar.（3）The epitope levels of LM18, LM19and LM20antibodies in the resistant cultivarbefore pathogen inoculation were a little bit higher than those in the susceptible one. Newsignal labeled by these3antibodies appeared in the cells enclosed by pericycle induced bypathogen inoculation was stronger in the resistant cultivar when compared to thesusceptible one.The results show that the wax gourd resistance to Fusarium oxysporum was not only with thepectinase activity, but also with pathogenic conditions.