Development Characteristics Of Tobacco Plants And Analysis On Leaf Chemical Composition For Newly Flue-cured Tobacco Varieties

Tobacco variety is the genetic basis of yield and quality, an admirable variety is the premise condition of tobacco leaf production. It requires not only a suitable environment, and the varieties and cultivation measures have certain restriction conditions. Thereby, this paper studied the growth characteristics and tobacco leaf chemical component on eight newly flue-cured tobacco varieties, the main results were as follows:1. The highest activity of nitrate reductase in tobacco seedling was Nanjiang3, the highest invertase activity was Xiangyan3, the highest root activity was C4288and Xiangyan3. The nitrogen response was different in different varieties at the seedling stage.2. In the aspect of mineral nutrition absorption, the differences on the absorption of nitrogen accumulation were smaller, and the tobacco plant had a significant demand for nitrogen at fast-growing stage. In75days after transplanting, nitrogen absorption and accumulation were remain relatively strong for the varieties Yunyan97, Xiangyan3and K326. The nitrogen accumulation showed some differences in different varieties, and nitrogen absorption were still increased for the varieties Zhongyan201, Yunyan97, Nanjiang3and C4288in95days after transplanting. The potassium absorption and accumulation wasn’t significant in55-75days after transplanting, but it increased in55-95days after transplanting for Nanjiang3and K326.3. The nitrate reductase activity had an overall reducing trend in35days after transplanting, and the invertase activity had large differences in9varieties, only Zhongyan201and Yunyan202performed rise in35-55days after transplanting, Zhongyan201, Yunyan202, Nanjiang3, Guiyan4, K326performed fall in65days after transplanting, others performed rise. The invertase activity greatly raised in80days after transplanting and began to fall in95days after transplanting.4. At the stage of45days after transplanting, all the varieties had a stronger growth except Nanjiang3. In80days after transplanting, the plant height was109.4cm for Nanjiang3and others were110.0-120.0cm, the variety K326was only95.8cm. The highest leaf yield was Yueyan97, and then Guiyan4as well as Nanjiang3. The highest output value was also Yueyan97and the lowest was Zhongyan201.5. In the aspect of chemical components comprehensive evaluation, the best variety of lower and upper leaf was C4288, and then K326as well as Xiangyan3, with the medium performance of Zhongyan201, Yunyan202and Guiyan4, the worst varieties were Nanjiang3and Yueyan97. But the chemical components in upper leaf for Xiangyan3and Yunyan97weren’t so harmonious, because of the macromolecule compound content was higher, and the degradation was relatively slow in curing barns, and it’s better to extend the yellowing conditions to some extent in order to make tobacco leaves full turn yellow.