The Study On The Control Effect Of Composite Application Of BR On Root-knot Nematode In Tomato

With the expanding vegetable planting area,the disease caused by rootknot nematode was aggravated gradually,which has to become one of the most devastating diseases of greenhouse vegetables.In this study,3 kinds of nematicides(Velum,Biological,Neemheyoupo)were mixed with Brassinolide by potted planting mathods,3 experiments were carried out in the summer of 2015,the spring of 2016,and the summer of 2016.Through investigation of the tomato,disease index,disease incidence,growth index,photosynthetic indexes,protective enzyme activity,content of Pro,MDA,to investigate the best combination of Brassinolide and root-knot nematode resistant agent mixed,and the synergized action of BR against root-knot nematodes.The main results were as follows:1 Exogenous spraying BR significantly reduced the incidence of the disease,disease index,but improve the control effect.The results also showed that the application of BR alone had significant controlling of tomato root-knot nematode.The compound use of the medicament was better than the single use of each one.Among the treatments used alone,the Velum(T2)treatment had the best effect.The control effect of strain rate and reducing the rate of increase showed that,BR+Biological treatment was better than BR+Velum and BR+Neemheyoupo.But BR+Velum experimental treatment on the control effect was significantly higher than BR+Biological and BR+Neemheyoup,disease index was decreased by 51.89%~75.10%?55.97%~77.18%,control effect was increased by 106.50~136.66%?136.66%~188.63%,morbidity was decreased by 38.51%~54.61%?47.80%~62.59%.2 After inoculation with root-knot nematodes at different growth stages(CK+RKN)causing the plant growth was significantly inhibited,with the different treatments having significant difference compared with CK+RKN treatment.The effect of 3 kinds of nematicides agents after exogenous application of BR was better than each agent used alone.BR+Velum processing effect was best,followed by T5,T7.From the perspective of synergism,in terms of growth index of plant height,stem diameter,shoot fresh weight and shoot dry weight,BR+Velum and Velum alone was higher than BR+Biological and BR+Neemheyoup.3 The contents of photosynthetic pigments and chlorophyll fluorescence parameters of Tomato under different stress treatments showed that the tomato chlorophyll fluorescence parameters of Fv/Fm??PSII?q P were decreased with during the process of the growth and development,but q N gradually increased,and higher than CK+RKN.The contents of photosynthetic pigments and chlorophyll fluorescence parameters(Fv/Fm??PSII?q P?q N)of tomato leaves treated with chemical combination were higher than those of single treatments.T2(Velum)had the best effect in the separate treatment of the medicament.The effect of T3(BR+Velum)treatment was the best in the treatment of mixed use,followed by T5,T7.From the perspective of efficiency,synergistic effect BR+Velum and BR+Biological is better than BR+Neemheyoupo.To sum up,the tomato plants treated with T3(BR+Velum)had some effect on improving the fluorescence parameters and chlorophyll content.The results indicated that BR+Velum treatment could help the plants to absorb more light energy for photosynthesis.4 The tomato plants could increase the activity of protective enzymes under treated of root-knot nematode resistance addit with BR,and therefore the production and accumulation of reactive oxygen species were decreased under the stress of root knot nematodes;when the content of MDA was decreased,the degree of membrane lipid peroxidation was also decreased;increasing Pro content could enhance the resistance of plants to root-knot nematode infection.The effect of BR+Velum(T3)was better than other treatments and CK+RKN,when compared with CK+RKN,the difference was significant.In the aspect of BR,the protective effect of BR on the protective enzyme activity was the highest.In summary,the results showed that the application of BR+Velum had a synergistic effect on the control of tomato root-knot nematode,with the treatment of BR+Velum had the synergistic effect.Content of Pro,MDA,the biggest effect of BR to Biological.