农业植物病害IPM.ppt

* 1.9 Case study: Integrated management of Alternaria blight in carrots Introduction Efficacy of sole control measures Integrated of control measures Concluding remarks Alternaria dauci in carrots Carrot field infected with Alternaria dauci Carrot combine Chemical management of A. dauci Sprinkler irrigation 1 2 3 4 5 6 7 8 9 Air spraying Ground spraying Time (days) Fungicide treated plot Untreated control plot For management of A. dauci up to 4 sprays are applied each week and up to 40 sprays are applied in a growing season !!! Objective of the research To develop an integrated management strategy that will: 1. Reduce the number of sprays applied in a growing season; 2. Prevent disease development and yield losses Management of A. dauci Chemical fungicides (protectant, systemic) Cultural measures (spatial organization of planting, sanitation, irrigation type) Genetic (cultivar resistance) Sole application of measures Chemical and drip irrigation Cultivar resistance and chemical control Integration of measures Temporal and spatial dissemination of spores 0 4 8 12 16 20 24 0 100 200 300 400 Hour of the day No. of spores trapped (m3 air/h) west east Distance from source field (m) 0 100 200 300 400 500 600 700 0 10 20 30 40 Y=34.6-0 11X+0.0001X2-4E-08X3 R2=0.97 Disease severity (%) Spatial influence of an infected field on neighboring fields Wind direction Infected source field Neighboring affected field Spatial organization of plantings Wind direction 1 2 3 4 5 6 7 4 Effect of sanitation: burring of infected debris after harvest in the soil Hour of the day No. of spores trapped (m3 air/h) 0 4 8 12 16 20 24 0 100 200 300 400 500 Before after Optimization of chemical control 60 70 80 90 100 110 0 20 40 60 80 100 Disease severity (%) Untreated Bravo, Score Time (days after planting) Efficacy of various fungicides Why the systemic mobility of the fungicide is not an advantage? Development of A. dauci on carrot leaves Why the systemic mobility of the fun