Study On The Characteristic Formation And Key Cultivation Techniques Of Qing Tian Flavor Flue-cured Tobacco

The Tobacco is one of the important cash crops with leaf, occupies an important position innational economy. The formation of tobacco leaf quality characteristics has its own laws andcharacteristics. It is closely related with cultivars and ecology.soil samples in2008and tobacco samples from2008to2011in Liangshan Prefecture were studiedas tobacco materials to further demonstrate the typical Qingtian flavor type flue-cured tobacco qualitycharacteristics. Main indicators of different ecological types of soil nutrients and flue-cured tobaccoquality were determined systematically. Using the methods of factor analysis, canonical correlation,membership function and so on, we assessed the quality and located the characteristics of Liangshanflue-cured tobacco, discussed the causes of quality characteristics of the Qingtian style flue-curedtobacco from the ecological factors, cultivar characteristics, cultivation measures and other key factors,and proposed the key cultivation technique of producing the Qingtian style flue-cured tobacco.The main results are as follows:1．Characteristic localization of Liangshan tobacco leaf. Different flavor styles mean differentchemical components. According to the smoke panel test, descriptions of flavor and chemicalcomponent were clustered to three groups. Group one is typical Qingtian style, including faint scent andfresh to middle, which accounts for58.63percent of the flavor styles. Group two is atypical Qingtianstyle, including middle and middle to fresh styles, which accounts for31.03percent. Group three isdefined as other types, which could be described as full to middle, accounts for10.34percent.2． Typical Qingtian quality characteristics and the key indicator determination of Qingtian flavorstyle. It was suggested that Qingtian flavor style, means higher content of reducing sugar and total sugar,bigger ratio of sugar to alkali, nitrogen to alkali, sugar to nitrogen, lower content of total alkali, totalnitrogen. In the aspect of smoke panel test, the score of judging parameter, such as smoking aromaquality, taste, and miscellaneous gases are significantly higher than group two and group three. Theabove indexes of group two are significantly higher than others, The aroma capacity of group one andtwo are higher than group three significantly. Group two are more stimulating than the others. From this,it could be concluded that every smoke panel test of group one is better than others.The study showed that the key indexes and its scope of Qingtian style leaf are improved as follows,the ratio of sugar to alkali is12-16, sugar to nitrogen is14-18, total nitrogen is1.7%-2%, and nitrogento alkali is0.9-1. Its accuracy got checked through test in2011.3．Regionalism of Qingtian style plantation ecology.According to the study, the region was dividedto four areas by WARD cluster.Ⅰinvoles Dechang, Puge, Xichang and Ningnan, which named middlealtitude hot-rich area. Ⅱ involes Huidong and Huili, named middle-altitude warm area. Ⅲ involesMianning and Yuexi, named middle-altitude wet area, Ⅳ involves Yanyuan, named high altitudewarm-cool area.4．The investigations related to quality characteristics of Qingtian style. According to the ecology plantation repartition of Liangshan Qingtian style, combined with the clustering and value of differentecology factors, the contribution rates of climate, oil, cultivars to Qingtian style were figured up. Thecontribution rate of climate factor is46.64%, soil factor is30.16%, cultivar factor is23.21%.5．The contribution rates of ecology to Qingtian style. The contribution rates of ecology factorswere showed as: the contribution rate of mean temperature during mature period is11.09%. Soil pH is10.57%, sunshine is10.31%, mean temperature and amount of precipitation during seeding restoringand root extending periods are9.59%and9.40%,respectively. The mean temperature in fast growingstage is9.09%, available phosphorus is8.91%, amount of precipitation in fast growing stage is8.16%,organic matter is6.99%, available nitrogen is6.06%, available potassium is4.95%, the amount ofprecipitation in mature period is4.69%. The climate factor is62.33%, soil is37.67%. From the above,we could see that the climatic factors, mean temperature especially during the mature period, sunshine,and the amount of precipitation during seeding restoring and root extending periods, and the soil factors,pH and available nitrogen, affect the characteristic of tobacco.6.The suitable ecological condition of Qingtian style: The tobacco of Qingtian style would be easiergot on purple and red soil, between the attitude of1600-2000m. The suitable index of climatic factorsare as follows: The mean temperature and amount of precipitation are between18-25degree and100-120mm, during seeding restoring and root extending periods respectively,20-28degree,200-250mm during fast growing stage,20-25degree,500-600mm during mature period. The sunshine isbetween750-850h during filed period. The suitable index of soil factors are as follows, the pH of soil isbetween6-6.5, organic matter is20-25g/Kg, available potassium is more than200mg/Kg, availablephosphorus is20-40mg/Kg, available nitrogen is80-100mg/Kg,7．The key cultivation technique research of Qingtian style flue-cured tobacco. Cultivation techniqueis the guarantee of Qingtian style. According to the factors, such as cultivar screening, suitabletransplant time, nitrogen application rate, planting density, the number of remaining leaves, suitableorganic matched with inorganic fertilizer, the key cultivation technique was concluded as follows:Suitable Qingtian style flue-cured tobacco cultivars: Honghuadajinyuan is the suitable cultivar toproduce the Qingtian style flue-cured tobacco. Suitable period for transplanting: the flue-cured tobaccoin Liangshan District should ensure that the flue-cured tobacco be transplanted between during April20th to May10th..Rational fertilization technology: Honghuadajinyuan, which is a cultivar of Qingtianflavor style, the optimum amount of nitrogen in Liangshan is75kg/hm~2, but no more than105kg/hm~2,the ratio of NPK fertilizer is1:1:2~3, and make the organic manure and chemical fertilizers combined.Organic fertilizer matured by fungicide is7500kg/hm~2, The applied amount of nitrogen supplied bytobacco special fertilizer is500kg/hm~2. Suitable planting density and remained leaves number:Suitable planting density of Honghua is110cm×50cm, leaving the number of leaves19to21, you canestablish a good group structure, individual and group relations, which would be conducive to theformation of the Qingtian style characteristics of flue-cured tobacco.The research has a great significance for the full use of Liangshan ecological resource,optimization layout of sweet flavor tobacco production, improving tobacco leaf quality. Furthermore, it is vital for enhancing the visibility and competitiveness of Liangshan tabacco.