Study On The Synergetic Effect Of 2,4-DTBP And Fusarium On The Occurrence Of Fusarium Wilt In Lanzhou Lily

Lanzhou Lily is a perennial herb and famous local Gansu vegetable.The Lily Research Group of Gansu Agricultural University has proved through previous research that the phenolic acid 2,4-DTBP is an allelopathic and self-toxic substance of Lily lancifolium,and this substance is present in the soil of Lanzhou lilies in continuous cropping for 0-9 years.In Lanzhou lily cultivation practice,it was found that soil-borne diseases caused by Fusarium were serious.The research group has identified five disease-causing sickles,including Fusarium oxysporum and Fusarium solani,through the etiological study of the lily wilt disease in Lanzhou Lily area.Allelopathy theoretical studies have shown that crops that are prone to autotoxicity in general can also lead to a significant increase in the incidence of soil-borne diseases,and the allergic autotoxic substances of crops will reduce the growth capacity and resistance of crops and contribute to the occurrence of soil-borne diseases.In view of this,this study selected 2,4-DTBP,a sensitive allelopathic substance from the root system of Lilium lancifolium.The pathogenic microorganisms were F.oxysporum and F.solani.A two-factor experiment was designed to analyze whether the two treatments had a synergistic effect on the occurrence of Fusarium wilt in Lanzhou by analyzing and comparing the incidence of Fusarium wilt disease,disease index,plant growth physiological index and rhizosphere micro-ecological indicators.The main results are as follows:1.From the level of Lanzhou lily plant,the incidence of 0.10mmol·L^-12,4-DTBP and Fusarium Solanum was 92.85%and 55.35%,and the interaction between 0.15mmol·L^-12,4-DTBP and Fusarium oxysporum was 88.54%and 53.15%.The morbidity and disease index was the highest compared with the rest of the same group.At the level of Lily scales in Lanzhou,the disease index of 0.10mmol·L^-12,4-DTBP and Fusarium Solanum was 54.17%,and 0.15mmol L^-12,4-DTBP and Fusarium oxysporum were 51.39%,and the disease index was the highest compared with the rest of the same group.2,4-DTBP and pathogenic bacteria increased the incidence of lily wilt disease in Lanzhou compared to single factor treatment,and promote the occurrence of blight in Lanzhou Lily.The interaction effect of 0.10mmol·L^-11 2,4-DTBP and Fusarium solani,0.15mmol·L^-11 2,4-DTBP and Fusarium oxysporum has the most effective effect on the severity of the blight of Lanzhou lily.2.Compared with single factor treatment of 2,4-DTBP or pathogens,two-factor co-treatment significantly inhibited the growth of lily plants,significa ntly reduced the accumulation of dry matter above and below the ground,and significantly inhibited the growth of the root system.3.Compared with single factor treatment of 2,4-DTBP or pathogens,two-factor treatments of Lanzhou Lily chlorophyll fluorescence parameters actual photosynthetic quantum Yield Y?II?,electron transfer rate?ETR?and photochemical quenching coefficient?qP?all decreased significantly,PSII maximum photochemical efficiency Fv/Fm,PSII latent activity?Fv/Fo?,and non-photochemical quenching coefficient?NPQ?also showed a certain decline,resulting in a significant decline in photosynthesis of Lilium lancifolium leaves.Compared with single factor treatment of 2,4-DTBP or pathogens,the activities of SOD,POD,CAT and APX in two-factor co-treatment of Lanzhou Lily increased significantly.4.Compared with single factor treatment of 2,4-DTBP or pathogens,the number of bacteria and actinomycetes in the root system of Lilium lancifolium increased significantly with the two-factor co-treatment,but the number of bacteria decreased significantly.Compared with single factor treatment of 2,4-DTBP or pathogens,the invertase activity in the rhizosphere of Lanzhou lilies decreased significantly,and the catalase activity declined to varying degrees.Significantly increased,urease activity also showed a certain degree of increase.In summary,2,4-DTBP and pathogenic Fusarium have a synergistic effect on the occurrence of Lanzhou lily blight,exogenous 2,4-DTBP can be aggravated by Fusarium solani disease or sharp the incidence of wilt disease caused by Fusarium oxysporum infection in Lanzhou.2,4-DTBP can change the enzyme activity of the plant rhizosphere cultivation medium,promote the transition from the"bacterial type"to the"fungal type"in the cultivation medium microbial type,degrade the micro-ecological environment of the plant rhizosphere;inhibit the root growth and development,destruction the dynamic balance between the antioxidant enzyme system and free radicals of plants reduces the photosynthetic efficiency of the leaves,which in turn reduces the growth potential of the plants and inhibits the growth of the plants,and reduces the disease resistance of the plants.In the 0.10mmol·L^-10.20 mmol·L^-1 concentration range,0.10 mmol·L^-11 2,4-DTBP interacts with Fusarium solani,the interaction between 0.15 mmol·L^-1 2,4-DTBP and Fusarium oxysporum has the most significant effect on inhibiting plant growth and aggravating the incidence of wilt disease.The content of 2,4-DTBP in lily root exudation in Lanzhou had no correlation with the continuous cropping years,but was higher in the seedling stage and full flowering stage than in other periods,and the incidence of wilt disease in Lanzhou was mainly concentrated from May to July,there is a certain connection between them.The research team found that low concentrations of 2,4-DTBP promote sporulation of pathogenic Fusarium.Therefore,it is presumed that the root exudates may be one of the major chemical factors that cause the continuous pathogenic dysfunction of lily blight in Lanzhou.