Chen Zhenguo

Effect of fan speed changes on neutral aroma components of flue-cured tobacco during bulk curing.

Effects of different fan speed changes on the contents of neutral aroma constituents in flue-cured tobacco leaves during bulk curing period were studied by applying frequency conversion technology.The results showed that total contents of neutral aroma components were higher under the 1 450 r/min of rotation speed than those under the 960 r/min of rotation speed when the temperature was between 42 ℃ and 54 ℃.While they reached the highest under the 1450 r/min of rotation speed when the temperature was between 42 ℃ and 54 ℃ and 720 r/min afterward;in the meanwhile,the contents of carotenoids,aroma aminophenol,maillard reaction products,cemdrenoid and neophytadiene were all higer than those under the 1 450 r/min of rotation speed during the whole process.

Effects of Application Time of Base Fertilizer( 15 N) on Growth,Nicotine Content and Nicotine-N Resources of Flue-cured Tobacco

A field experiment with 15N isotope tracing was carried out to study the effects of application time of base fertilizer(0,15,30 d before transplanting) on the growth,nicotine content and nicotine-N resources of flue-cured tobacco.The results showed that both dry matter accumulation and nicotine concentration in flue-cured tobacco increased with the growing of tobacco plants.The concentration of nicotine decreased with the elevation of stalk position before topping,while it was on the contrary after topping.The dry matter weight above ground was increased by early application of base fertilizer,which also promoted the nicotine contents in lower leaves,while those in upper or middle leaves were not affected.The proportion of nicotine N sourced from N fertilizer decreased with the growing of plants and the elevation of stalk position;but not significantly affected by the time when the base fertilizer was applied.It suggested that properly earlier application of base fertilizer would benefit tobacco growth at no expense of its quality.