除虫菊(Chrysanthemum cinerarialefolium Bocc.)是提炼除虫菊酯的天然工业原料,我省平阳县于60年代后期开始试种。由于它耐瘠、栽培容易、管理方便、经济价值高,深受群众欢迎,目前已成为苍南县一种重要的冬季经济作物,常年种植面积1万余亩,总产量可达70多万斤。但连年种植后,除虫菊菌核病(Sclerotinia sclerotiorum)日益加重,缺株断垄现象屡见不鲜,对产量的影响很大,一般年份减产5～8％,严重年份减产1～2成。同时,除虫菊酯的含量也显著下降。据化验,健株花含菊素为0.8691～0.8683％,病株花含菊素为0.5066～0.4998％,降低了40％左右。为了促进除虫菊生产的发展,1980年以来,我们对除虫菊 Pyrethrum (Chrysanthemum cinerarialefolium Bocc.) Is a natural industrial raw material for pyrethrin extraction. Pingyang County in our province started trial planting in the late 1960s. Because of its resistance to barren, easy cultivation, convenient management, high economic value, welcomed by the masses, Cangnan County has now become an important winter cash crop, perennial planting area of ​​more than 10,000 acres, the total output of up to 70 million kg. However, after successive years of planting, Sclerotinia sclerotiorum is aggravating day by day. The phenomenon of lacking of lines and breaking of ridges is common and has a great impact on the yield. Generally, the annual yield is reduced by 5 to 8% and that in severe years is reduced by 1 to 2%. At the same time, the content of pyrethrins also dropped significantly. According to the test, the healthy plant flower contains 0.8691 ~ 0.8683% of daisy, the diseased plant contains 0.5066 ~ 0.4998% of daisy, which reduces about 40%. In order to promote the development of pyrethrum production, we have been on pyrethrum since 1980