Effect Of Base And Foliar Applications Of Potassium Fertilizer On Fule-Cured Tobacoo Leaves

As a widely grown and important economic crop around the world , tobacco is vastly raised in China.Yet,China has become the world's largest tobacco producer.However,there are still a wide quality gap between China and the high-quality tobacco-producing countries,the main reason of the problems is the low potassium content of tobacco. the leaf potassium content of high-quality tobacco is generally not less than 3%, and the tobacco with high potassium content have a better combustion and smoldering fire holding. The United States and several high-quality tobacco product countries' leaf potassium content of tobacco leaves are as high as 4% to 6%, while the potassium content of our tobacco is generally less than 2%.At present, addition to Yunnan, Guizhou, Fujian, whose leaf potassium content are more than 2%, other provinces in China are at 2% or less, this situation is seriously restricting the development of China's current tobacco production.In recent years, a lot of researches has been done to explore how to improve the potassium content of tobacco.Study found that potassium is one of the most important quality element of tobacco leaves, its demand is 1.4 times more nitrogen, and 3.5 times more phosphorus , adequate K supply is an important condition for high-quality tobacco. K can be absorbed by plant roots ,it can also be absorbed by plant foliage, and leaf absorption efficiency will be higher. As the root system has begun to age when the flue-cured tobacco harvest , so absorption capability has been greatly reduced, if the flue-cured tobacco contains more potassium at this time, it will make tobacco more resistant to mature and better qualitied.Therefore, some of China's tobacco-growing areas are often has the habit of spraying potash in the late growing stage,which has made some income benefits, but this experience has not been systematic studied.Therefore , this paper aiming at the actual condition of low quality of flue-cured tobacco ,through a pot experiment of Qin96,the successive change of potassium content in the tobacco's segment, middle and lower layers leaves were studied,besides, With comprehensive quality of tobacco as criteria,the alone and the combined effect of two methods of potassium applications were compared,which provide some clues for further research on tobacco potassium. The study was to evaluate the effect of different applications of potassium fertilizer on flue-cured tobacco leaves and total quality through pot experiment. The results show that an increase of base potassium fertilizer content will increase reducible sugar, total sugar content. Foliar application of potassium fertilizer will reduce the leaf chlorophyll content and tobacco nicotine, total nitrogen content of middle and high level of base potassium fertilizer treatments. Besides,it will balance the potassium content of different layers' leaves,and optimize the various components of flue-cured tobacco leaves to enhance the quality.The Foliar application of potassium fertilizer and base potassium fertilizer both influence the various chemical components of tobacco leaves. The experiment proved that improve the basic fertilizer alone cannot make successive increase of potassium content of tobacco , but the results to improve the comprehensive quality of tobacco are obvious with foliar application of potash fertilizer distribution.While middle level of base potassium fertilizer treatments combined with 0.2mol/L K( 1/2K2SO4) foliar application produce the best results.