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菊科单冠毛属植物 Haplopappus gracilis,原产墨西哥北部高原地区,从美国西南部引入日本后,1984年引入我国。它的体细胞染色体数目为2N=4,是高等植物中染色体数目最少的一种植物。一年生,株高0.3—0.5米,茎柔软,叶小裂片呈线形。头状花序,小花呈管状花,黄色,结很小的瘦果,成熟后,冠毛与果实不分离。栽培方法:北京地区,3—6月播种。由于种子发芽率不高,播种前应先把做砂床用的砂子,烘烤1—2小时进行消毒。播种后,盖砂不
Compositae Haplopappus gracilis, originating in the northern plateau of Mexico, was introduced to China in 1984 after it was introduced into Japan from the southwestern United States. Its somatic chromosome number is 2N = 4, which is the plant with the least number of chromosomes in higher plants. Annual, plant height 0.3-0.5 meters, stems soft, lobular lobes were linear. Flower head, tubular flowers, yellow, knot small achenes, mature, the crested hair and fruit are not separated. Cultivation method: Beijing area, 3-6 seeding. As the seed germination rate is not high, before planting the sand bed should be done with sand, baking 1-2 hours for disinfection. After planting, cover the sand is not