Analysis Of Influencing Factors Of Tobacco Oil And The Relationship Between Tobacco Oil And Quality Of Flue-cured Tobacco In Qujing Tobacco-growing Area

On the basis of 2541 flue-cured tobacco leaves(grade C3F)collected at 90 villages and towns in 9 tobacco-growing cities(counties)of Qujing,through collecting the corresponding climate data of sampling points,the overall situation of tobacco oil of flue-cured tobacco in Qujing tobacco-growing areas were analyzed,the difference of tobacco oil in different villages or towns(Qilin,Fuyuan,Huize,Luliang,Luoping,Malong,Shizong,Xuanwei,Zhanyi)and different flue-cured tobacco varieties(K326,NC102,NC297,Honghuadajinyuan,Yunyan85,Yunyan87,Yunyan97,Zhongyan100)were compared,the influence of edaphic factors(p H,OM,N,P,K,Zn,B)and climate factors(light duration,temperature,precipitation)on oil in flue-cured tobacco were clarified,and relationship between tobacco oil and quality indicators(appearance quality,physical properties,chemical composition,sensory quality)was studied,the main conclusions were as follows:1、The overall situation of tobacco oil of 2541 samples in Qujing tobacco-growing areas were statistical analyzed,results showed that Qujing tobacco oil scored an average of 5.7,reach the level of oily to less oily,the standard deviation was 1.52,the variation coefficient was 26.7%,the proportion of tobacco leaf with the grade of oily and less oily were larger,which were respectively reach 41.24 percent and 57.42 percent,the proportion of tobacco leaf with the grade of “rich” and “oily” was 57.93%,the grade of “less oily” was 41.24%.Taking all things into consideration,skewness coefficient of tobacco oil distribution curve was ﹣ 0.246,kurtosis coefficient was ﹣1.251,similar to normal distribution.2.Difference of oil in flue-cured tobacco at Qujing tobacco-growing areas in different counties and different tobacco varieties were researched,the main conclusions included the following aspects: 1)Oil in flue-cured tobacco difference among different cigarette production counties,tobacco oil in Fuyuan,Huize,Luliang,Malong,Qilin,Shizong were better,whose average score were all more than 6,reach the level of “oily-”,tobacco oil in Xuanwei and Luoping were poorer,whose average score were all less than 4.5.As far as variable coefficient,the score distribution of tobacco oil in Qilin and Huize were relatively concentrated,which in Xuanwei and Zhanyi were uneven distributed.2)In the tested tobacco varieties,the average score of tobacco oil of Zhongyan 100 was 8,variable coefficient was 0,all reached the level of “oily+”,the average score of tobacco oil of NC102、NC297 were all more than 6,discrete degree were relatively small,the average score of tobacco oil of Honghuadajinyuan,Yunyan85,Yunyan87 and Yunyan97 were lower(5.69-5.86),discrete degree were larger,while there were no obvious difference between each other,the average score of tobacco oil of K326 relative to a minimum,discrete degree was relatively bigger.3.Oil factors in Qujing tobacco-growing areas and their influence on oil in flue-cured tobacco were researched.Results showed that soil in Qujing tobacco-growing areas inclined to alkaline as a whole,organic matter content in soil was lower,alkali-hydrolyzable nitrogen,available phosphorus and available potassium in soil were uneven distributed,and the content of available potassium was generally low,which couldn’t satisfy the needs of tobacco growth and development,effective Zn and B in soil distributed unevenly,and the content of effective Zn was extremely low in local area.Results indicated that tobacco oil was closely related with soil factors.With the increase of soil p H,tobacco leaf oil content gradually reduced,with the increase of the content of alkali-hydrolyzable nitrogen and organic matter in soil,the tobacco leaf oil content showed a trend of increased after decreased first,when the content of soil organic matter range from 15 to 25 g/kg,alkali-hydrolyzable nitrogen 100 to 150 mg/kg,the proportion of tobacco leaf with more oil reached maximum.With the increase of available potassium content in soil,tobacco oil showed a trend of increasing.With the increase of effective Zn content in soil,tobacco oil gradually increase,while when the soil effective Zn content was more than 3 mg/kg,tobacco oil reduced.Tobacco leaf oil content gradually increased with the increase of soil effective B content,when soil effective B content in 0.5-1.0mg/kg,the proportion of tobacco leave with more oil reach maximum,then reduced with the increase of soil effective boron content.4.Based on 9 flue-cured tobacco varieties of 90 towns in 9 tobacco-growing cities(counties)in Qujing as materials,climate conditions of Qujing tobacco-growing areas and its relationship with tobacco oil were studied through collecting the corresponding climate data of sampling points.Results showed that compared with foreign high-quality tobacco-growing areas,less light,rainy and shortage of heat in later growth period were the main climate factors limiting the quality of tobacco leaves in Qujing tobacco-growing areas,the climate of Qujing tobacco-growing cities(counties)were divided into 3 categories according to the difference of light,rainfall and heat distribution.Climate of flue-cured tobacco was closely associated with tobacco leaf oil,and climate characteristics of tobacco leaves with more oil mainly included the following several aspects: more sunlight hours in growth period,higher effective accumulated temperature stability through 17℃,relatively lower average temperature and more rainfall in early growing period,and relatively higher average temperature and less rainfall in later growing period.Regression analysis results showed that when the sunlight hours during growth period > 670 h,effective accumulated temperature stability through 17℃ > 180℃,early growing period average temperature 17~17.5℃,rainfall 122~140mm,later growing period average temperature 19~19.3℃,rainfall 520~590mm,tobacco leaf oil would reach the level of rich and oily.5.Relationship between tobacco oil and quality indicators was studied with 2541 flue-cured tobacco samples in Qujing tobacco-growing area as materials.Results showed that tobacco oil had extremely significantly positive relation with identity and color intensity,significant positive correlation with leaf color,maturity score increased with the increasing oil till its peak and then reduced.The stem ratio significantly reduced and the leaf density significantly increased with increasing oil.With the increase of tobacco oil,the content of starch,total sugar and nicotine gradually increased,the chlorine content gradually decreased.The scores of aroma quality,aroma amount,offensive odor,irritancy and aftertaste improved with increasing oil.