Abstract: To explore the effect of different leaf age on the yield and quality of flue-cured tobacco,the main cultivars K236 in Luoping tobacco-growing area of Yunnan were used as test materials to construct different flue-cured tobacco varieties with different leaf age. Photosynthetic potential in growth period and economic characters of post-baked tobacco leaf were analyzed. The results showed that with the increase of transplanting age,the survival rate of tobacco seedlings increased first and then decreased,while the field growth period increased; With the advance of fertility in the field of flue-cured tobacco,the photosynthetic potential (LAD) of the treatments decreased first and then increased,and the total LAD of the treatments was the highest in 5 leaves transplanted tobacco seedlings,which was 20.14% higher than that of 6 and 8 leaves respectively,14.82%. The mean leaf angle (MLIA) of the population increased first and then decreased with the increase of leaf age,while the extinction coefficient (K)was an increasing trend.The leaf tobacco leaves with 5 leaves were transplanted with appropriate chemical components and the quality was the best,followed by 4 leaves;6,7,8 leaves,because of its reducing sugar,starch,potassium content does not meet the requirements of high-quality tobacco chemical indicators,poor quality;With the increase of transplanting age,economic traits showed a trend of increasing first and then decreasing. Therefore,the optimum tobacco leaf transplanting age of tobacco leaves in Luoping tobacco-producing areas in Yunnan is 5-leaf-stage,which can shorten the period of nursery and shorten the time of cutting and reduce the time when the high yield value can be maintained. Such as smoke and the proportion of medium and high smoke,improve the grade structure and site structure.

Key words: Flue-cured tobacco, Leaf age, Photosynthetic production, Quality, Economic traits

CLC Number: 

• S572