Research Of Key Technologies In Little Canopy Floating System For Flue-Cured Tobacco Seedlings In YuXi City

Research of Floating System of flue-cured tobacco began in 1998 in Yuxi and the technology expended widely in 2000. In 2003, the expand rate of it reached 80% in the whole city. Therefore, Floating System of the flue-cured tobacco was the most important in of seedling technology in Yunxi, even in the Yunnan Province. Most important, the skills of developing seedlings in small hutch adapt to real situation of farmers who plant tobacco in Yuxi city.The study conducted during the climax of expansion of Floating System of flue-cured tobacco. And it was the summary that based on the early little canopy Floating system seedling technology. It focused on the technology of little canopy Floating System of flue-cured tobacco during the expansion in Yuxi. The whole experiment was done in two years. From Feb to Jul, in 2003, the experiment was conducted in the flue-cured tobacco of breeding base of Jiangchuan Country, Yuxi City while it was in seedling base of flue-cured tobacco in Hongta tower district, Yuxi City and technology garden of college of Yuxi agricultural occupation and technology from Feb to Jul, in 2004. The experimental varieties were Honghuadajinyuan,, K326, Yunyan85, Yunyan87. Results showed that the best coated rate of coated seed for Floating System of flue-cured tobacco was below 80. It was also screened the best medium, which mainly involved in peat, perlite, humus, vermiculite. The strength of light was different at differ time. At early time, from germination to 2 leaves of seedling, the best light strength was 4000-10000 LAX and covered 1 layer of black plastic. The 75% of light was shed. At middle time, 2 leaves of seedling, the best light strength was 10000-18000 LAX and uncovered 1 layer of black plastic. And the later time, 5 leaves of seedling, the best light strength was 12000-30000LAX and uncovered all the plastics. To press the media tightly, by throwing it high in the air, then falling on the ground for three times, will help the sprout result. The depth of sowing would influence the percentage of spiral root and survival of tobacco greatly. The best depth of sowing was 2mm. Leaf cutting should be at 2-4cm away from heart leaf. Heavy cutting would inhibit the growth of tobacco plant and the probability of factitious disease infection would increase. However, light cutting would lead to be high stem seedling and blooming early. Normally, tobacco seedling bred by Floating System was stronger than others. After it was transplanted, budding and mature time was little later than that of normal seedlings. However, it has higher yield and cost of yield and less disease. In the experiment that effects of different pH on the growth of tobacco in little canopy Floating System, the result showed that the best pH of nutrient solution was7.0. After experiment, we also got the quantitative indexes of water management and fertilization application during the seedling breeding. When transplanting, it should be more water and deep transplanted, especially, in the dry land. Furthermore, it was also expounded about the detail method and problems and further analysis on the successful experiment during the technology expansion. From above, it will improve the Floating System.