Abstract:In order to explore the optimal dyestripping time of flue-cured tobacco at different altitudes, the paper studies the conjunctiva of flue-cured tobacco at different altitudes in Panxi tobacco-growing areas. Three experimental sites were selected, Miyi Puwei, Yanbian Heai, and Renhe Pindi, which are 1 600 m, 1 800 m, and 2 000 m high respectively, and are set as follows: . 35 days after transplanting dyestripping shangxiang; Ⅱ. Dyestripping shangxiang after transplanting 45 days after transplanting;Ⅲ. Conventional dyestripping; Ⅳ. Not dyestripping, 4 treatment. The flue-cured tobacco varieties were tested, and the effects of different dyestripping time and different altitudes on the growth period, field disease, agronomic characters and physiological and biochemical indexes of flue-cured tobacco were studied. The main conclusions are as follows: at the same time, with the increase of altitudes, the growth period delay and the number of leaves and the width of leaves decrease, the same level height change is not obvious and the dyestripping time has little effect on the tobacco growth period process. The disease incidence was at a low level, and the relationship between disease occurrence and altitude and dyestripping time was not clear. At the same dyestripping time, the width of number of plate and leaf decreased with the elevation, while at the same elevation, the number of leaves and the width of running time were not obvious with the change of dyestripping time. At 1 600 m above sea level, early dyestripping is conducive to the root formation and environmental adaptability. At 1 800 m, dyestripping was favorable to the synthesis of sugar and protein and root formation. At 2 000 m, root growth of dyestripping should better be 35 days after transplanting.