Research On Key Technologies For Quality Improvement Of Upper Leaves Of Tobacco

The quality of upper leaves of tobacco in Nanping need to be improved.The existing problems are mainly as follows:improving the maturity of upper leaves,reducing nicotine content,improving tobacco aroma,reducing green gas and irritation.We did research on soil improvement,cultivation,harvesting and curing in order to promote the quality and industrial usability of upper leaves.The results are as follow:(1)The best use level of dolomite dust is 1125kg/hm2,which is better for the growth of tobacco,improving agronomic traits,disease occurrence leaf quality and economic traits;(2)Proportion of organic manure at 35%is better for agronomic traits,disease occurrence,economic traits and leaf quality;(3)The new medium is good for the growth period,agronomic characters and disease occurrence,it can replace traditional medium.(4)The new seedling plate is better for the quality of tobacco seedlings,agronomic characters and disease occurrence.(5)The 60:40 treatment of base-chase ratio has little effect on agronomic characters,but its economic characters and leaf quality of B2F is the best.(6)Different colors topping strategy is better for the upper leaves,the incidence of disease is lower,economic characters is better.(7)The time of removing lower leaves has great influence,with the delaying of the optimization time,which is better for economic characters and leaf quality of upper leaves.(8)The maturity of tobacco leaves can be determined by SPAD.The upper leaves with SPAD value 11-15 shows the best appearance quality and better chemical components.(9)Which 6 leaves on the top of the tobacco plant harvested and cured together,the appearance quality and chemical components of tobacco leaves are the best.