Pathogenic Relationship Between Meloidogyne Incognita And Ralstonia Solanacearum On Tomato Plants

General rotation design was used to analyze influence of quantity and time of inoculation of Southern root-knot nematode(SRKN,Meloidogyne incognita)on pathogenicity of tomato plants which inoculated with Ralstonia solanacearum.The results shows:The seedling of host plant height that were inoculated nematodes than the non-inoculated lower.The impact of changes in stem diameter is not significantly.Root fresh weight and root volume first decreased and then increased;But in the adult stages the morphological indexes were inapparent. During the seedling stages,the chlorophyll contents that inoculated nematodes were lower than the non-inoculated nematodes treatments.To the adult stages,chlorophyll contents increased,but,Chla/Chlb was reduced obviously,and the foliage of tomato plants became yellow.Proline contents of the seedlings did not change significantly, but the adult plants also substantially increased.Proline content can be increased to maintain the osmotic pressure of host cells.The vitality of the seedling root had a larger changes.Compared to the non-inoculated with the nematode,the root activities of inoculated treatments decreased significantly.Untill the adult stages,all treatments, including inoculated treatments and non-inoculated treatments,the root activities reduced apparently.In this stages,the plant root activities little effected by the number of nematodes and the time of inoculation.Seedling peroxidase and catalase activities were significantly increased,and effected by the number of nematodes.The two enzyme activities with a large quantity of nematodes increased to higher than the the small amount of nematodes.Phase two of the adult plant enzyme activities were decreased.In two physiological periods,peroxidase and catalase activities were deeply affected by the amount of nematodes and the time of inoculation.Seedling MDA contents increased,and then had a slightly higher in adult periods.The amount of nematodes and the time of inoculation had a little impacts in it.Seedling all treatments the relative conductivity increased.From seedlings to mature periods also substantially increased.The amount of nematodes and the time of inoculation had a large effects in the relative conductivity.The treatments were inoculated early increased to a greater extent,and late inoculation increased lesser extent.POD isoenzyme from the changes,with the different in the amount of nematodes inculated and the time of inoculation,POD isoenzyme spectra showed differences.The pre-inoculation and a larger volume of worms,were not only to bring more spectra, but also have the enzyme with greater intensity. From the nematode infection on the incidence of bacterial wilt affected by the results of the survey,the treatment 6 non-inoculated nematodes hold the average incidence rate of 60%,but,Other treatments inoculated nematodes hole the incidence rate between 70%and 100%.Through the survey to root-knot nematodes reproduction rate indicated,the greater the initial inoculated volume,the smaller its reproduction rate.This may be due to the results of competition in nutrients and survival spaces.The results of analyses of principle effective factors and cross effects of the time of inoculation and the number of nematodes inoculated caused the affected plants serious pathological changes.The experiment also showed:with a view to pathological changes,it determined on the time of infection and the population of nematodes,and the impact on growth seedling periods more serious than the adult stages.It was suggested that earlier prevention and control of root-knot nematodes should be a major significance in controlling bacterial wilt disease of tomato.