The Occurrence Rules And Harness Measures Of Rose Black Spot In Chenshan Botanical Garden

There are462Rose varieties in Shanghai Chenshan botanicalgarden, most of them infect Rose black spot. It will be useful forpreventing the Rose black spot and introducing the fine Rosevarieties by studying the Rose black spot occurrence rules andharness measures in Shanghai Chenshan botanical garden.The observation of some Rose′s disease leaves indentified themost conidia are M.rosae (Lib.) Died..The length of every Rose′sconidia significant differences.Regular survey of the Rose black spot found: Rose black spotstarted in May. It′s to the first peak in June. The disease leavesrate fell in July, the rate rise gradually in August to October.the investigating of botanical Rose black spot and temperatureIn2011shows: the optimum temperature for Rose hypha′s growth andconidia′s production is20-30℃.the most optimum temperature isabout25℃. the investigating of botanical Rose black spot andrainfall In2011shows: in the optimum temperature the developmentof Rose black spot and the rainfall are related.The pathogenicity index of the different Rosa varieties shows:Floribundas﹥Grandifloras﹥Hybrid Tea Roses﹥Miniature Roses﹥Shrubs﹥Rosa multiflora﹥Polyanthas﹥Climbers﹥Rosa rugosa,their pathogenicity indexes is92,85,84,84,83,79,78,78,75. the Rosa varieties of The higher pathogenicity index have morelong conidia. The pathogenicity index of the different color Rosavarieties shows: pink﹤yellow﹤orange﹤red﹤white﹤purple.the survey of The Rose pathogenicity index shows the disease leavesrate differences of different Rose varieties are significant.The bactericide test show the effect:75%Chlorothalonil﹥80%Mancozeb﹥60%Pyrazole ether﹥10%Difenoconazole﹥25%Azoxystrobin,Their effect are75%,50%,50%,40%,12%.