Study on the Variation of Soluble Protien Content during Different Growth Stages of Tobacco

The seedlings of tobacco variety burley 21 were pot cultured in greenhouse for the extraction of soluble protein in order to find the proper harvest stages for get both higher fresh leaf biomass and higher solulle protein yield.The results showed that the appropriate time is at 8~9 weeks after transplantation when harvested only once.In Jiang-huai area, the fresh leaves of tobacco could be harvested three times during the whole grow th period.The proper times are 6 weeks, 9~10 weeks and 13~14 weeks after transplantation.