Adaptability, Appropriate Nitrogen Application Rate And Tobacco-Leaf Roasting Technology For Some New Flue-cured Tobacco Varieties In Shaotong City Of Yunnan Province

In order to increase diversity of flue-cured tobacco variety and accelerate extension of new flue-cured tobacco variety in Shaotong city of Yunnan province, the experiments of adaptability, appropriate application rate of nitrogen fertilizer and matched leaf-roasting technology were conducted in 2005 using Yunyan97, Yunyan203 and YH05 three new flue-cured tobacco varieties based on regional experiments of 2002-2004.The results of adaptability experiment showed that yield of each new variety was higher than that of control Yunyan85 and among which YH05 with highest, yield of Yunyan97 ranked the second and Yunyan203 the third. Yunyan97 was with the highest rate of top grade tobacco leaf and YH05 with the lowest. Yunyan97 also was with the highest production value of per unit of land Yunyan203 with the lowest. The investigation of field diseases resistance showed the diseases resistance of Yunyan203 and YH05 were better than control and Yunyan97 was similar with control. Based on the results mentioned above, it could be concluded that Yunyan 97 was with highest adaptability and was suitable to be planted in whole tobacco region of Shaotong city, YH05 was with higher diseases-resistance, especially for TMV and suitable to be planted in land with middle and low soil fertility, Yunyan203 was with high TMV and CMV-resistance and could be planted in areas where TMV was easily occurred.The results of fertilizer demand experiment showed that the appropriate application rate of nitrogen was 90 kgN for Yunyan97, 75kgN for Yunyan203 and 75 to 82.5 kgN for YH05 per hectare respectively in middle fertility soil in Saoton city.The results of tobacco leaves roasting technology experiment showed that YH05 tobacco leaves should be roasted to yellow under high temperature and middle humidity and fixed color under rapidly increasing of temperature; Yunyan203 tobacco leaves should be roasted to yellow under middle temperature and humidity and fixed color under middle increasing rate of temperature; Yunyan97 tobacco leaves should be roasted yellow under middle temperature and humidity and fixed color under slow increasing of temperature.