Abstract:

In order to resolve the influence of low temperature during seedling-breeding on the growth of tobacco in southern tobacco region, effects of different technologies in floating system on chemical composition and economic character of flue-cured tobacco were researched. Results show that: the safe seedlings with the ability of defending low-temperature had an exuberant growth after transplantation , the number of effective leaves and the plant height significantly higher than the normal seedlings, the contents of chlorophyll and carotene increased in leaves’ function period while the degradation time was postponed and the speed was slowed down in mature period. The safe seedlings was in the favor of raising the content of starch in the leaves and decreasing the nicotine in the leaves and with remarkable higher yield and output value, they had the same chemical harmony, average price and the percentage of high quality tobacco as the normal seedlings, this technology can be popularized in south tobacco-planting area.