Effects of Harvesting Method and Time on Alkaloids Content in Burley Leaves from Different Stalk Positions

Field experiments were conducted to investigate the effects of harvesting method and time on the differences in alkaloid content and nitrogen-nicotine ratio among cv.Dabei 1 cured leaves from different stalk positions.The results showed that the differences in alkaloid and nitrogen contents among stalk positions were smaller in cured leaves harvested by whole stalk cutting than those by stalk cutting and partial priming,while the differences in alkaloid and nitrogen contents and nitrogen-alkaloid ratio were the biggest by full priming.Early cutting resulted in smaller differences in alkaloid content,and with the delay of cutting time,the differences increased due to alkaloid accumulation in upper leaves greater than that in lower leaves.