Studies On The Characteristics And Key Technique Of Harvesting And Curing Of Different Fresh Leaves Of Flue-cured Tobacco In Sichuan Growing Area

Yunyan 87 and Honghuadajinyuan was taken as the experimental materials to explore the characteristics and key technology of harvesting and curing of different fresh leaves of flue-curingtobaccoin Sichuan growing area.It could provide theoretical basis and technical support for bulk flue-curing in Sichuan Province.The main results are as follows:(1)The characteristics of different varieties,parts and maturity of flue-cured tobacco were studied.The contents of chlorophyll,carotenoid,total sugar,reducing sugar,total nitrogen,total plant alkaloids and protein of Yunyan87 were higher than those of Honghuadajinyuan,only leaf ratio and the starch content reverse.The easy curing potential and holding curing potential of Yunyan 87 are better than Honghuadajinyuan.The contents of chlorophyll,carotenoid,total sugar and reducing sugar were decreased,the contents of starch and total plant alkaloids were increasd,nitrogen and protein content were decreased first and then increased with the increase of the position of fresh tobacco.The ratio of carotenoid to chlorophyll in cutters was the highest,the leaf was the lowest.The cuing characteristics were better in cutters.The contents of chlorophyll,carotenoid,total nitrogen,total plant alkaloid and protein content of fresh smoke were decreased,the ratio of of carotenoid to chlorophyll,total sugar and reducingsugar content showed an increasing trend,the starch content was first increased and then decreased trend,the better fresh tobacco leaves’ easy curing potential and the worserholding curing potentialwith the increase of maturity.The M2 is better in easy curing potential and holding curing potentialin all tobacco leaves parts.(2)The maturity of different fresh tobacco leaves were studied.To comprehensively analyze cured tobacco leaves,the appearance quality,the economic benefit,the chemical composition and the smoking quality should all be considered.This study showed:The best harvestof Yunyan 87’ lugs,cutters and leaf werein leaf yellow-green area of 60-70%,70-80%,80-90%.The best harvest of Honghuadajinyuan’ lugs,cutters and leaf werein leaf yellow-green area of70-80%,70-80% and 90-100%.(3)The color parameter index and discriminant function of different fresh t obacco were studied.By measuring the color parameter of different maturity of Yunyan87’fresh tobacco leaves,we determined the lugs’ suitable L value,a value and b value was 44.5~47.4,-5.56~-4.64 and 31.02~33.78;The cutters’ suitable L value,a value and b value was 48.65~50.95,-8.24~-6.76 and 34.74~37.06;The leaf ’ suitable L value,a value and b value was47.3~50.7,-11.05~-8.75 and 35.49~37.51;Maturity degrees of tobacco leaves could be predicted based on the quantitative discriminant model,which is constructed by L,a,b,with cross validation method to predict the original sample,to accurately predict the rate of 9 6.3%,the discriminant accuracy of the new samples reached 95.6%,fresh tobacco maturity judgment accuracy was increased significantly.The color parameter and its determination function can be used as a new technology to determine the grade of the maturity of fresh tobacco.(4)With the progress of curing,the water content,chlorophyll and carotenoid content are continuously reduced;The content of fresh starch starch,which is represented by Yunyan 87,is decreasing and the content of total sugar and reducing sugar is increasing.To comprehensively analyze cured tobacco leaves,the appearance quality,the economic benefit,the chemical composition and the smoking quality should all be considered.The result showed that the treatment of T4 was best in the quality of Yunyan87’ lugs cured tobacoo,the treatment of T3 was best in the quality of Yunyan87’ cutter and leaf cured tobacoo,the treatment of T4 was best in the quality of Honghuadajinyuan’all parts cured tobacoo.