Study On Effects Of Tobcco Leaf Maturity Stage On Yield And Quality In Ye County Base Unit

One of the main reasons for the quality problem of tobacco leaves produced by tobacco production base unit of Yexian County was the insufficient control of tobacco maturity,especially for the middle and upper parts.To satisfy the demand of,"Guiyan" brand cigarette,a series of research work was carried out to accurately know the tobacco maturity and improve the industrial availability of "luzhou-flavor" tobacco leaves of Yexian County in the two years of 2014 and 2015.In this paper,the gradient of the harvest time of the upper and middle parts of tobacco leaf was delayed,and the effects of various harvest time on the agronomic characters and the appearanceof fresh tobacco leaf,as well as the quality of appearance,chemical composition,internal quality?economy and safety of flue-cured tobacco were analyzed.The main research results were as follows:1.The different harvest time has an impact on the representation of fresh tobacco leaves With the delay of harvest time,some characters of tobacco leaves,such as the yellowing degree,the degree of foliage shedding,the brightness of leaf surface and the degree of whitening of main vein,have increased and the color of branch leaveswas also changed from green to yellow.2.The different harvest time has an obvious effect on the appearance quality of flue-cured tobacco leaves.With the delay of harvest time,the tobacco maturity improved and the color gradually deepened.In the certain delay time,the oil content in the tobacco leaves gradually increased,the aroma became prominent and comfortable,and the identity became thinner.Meanwhile,the structure of leaf became more loose,soft and elastic,and the color also became strong.However,if the harvest time delayed too long,tobacco leaf oil would be reduced significantly,surface area of damaged leaves would be increased and the dry sides and disease spotswere also increased.3?Different harvest time have an influence on economic characters of flue-cured tobacco leaves.With the delay in harvest time,the quality and the ratio of mid highgradeleaves was increased 1-2%,but its yield was decreased4?With the delay of harvest time,the contents of total sugar,reducing sugar and nicotine decreased;the content of potassium ion and the ratio of two sugars increased;the content of pesticide residue and heavy metal decreased.The chemical composition and contents forpostponing 4-day harvested middle leaves and 6 days upper leaves were more suitable,especially the pesticide residue and heavy metal have the lower range.5.With the delay of harvest time,the aroma of tobacco leaves was improved,such as delicate smoke,the soft degree enhancement,the stimulation reduces,the comfortable feeling enhancement.The results showed that he middle leaves postponed for 4 days and the upper leaves delayed by 6 days can meet the demand of tobacco quality"Guiyan"brand.6.New industrial formula for postponing 4-day harvested middle leaves and 6 days upper leaves had the following characteristics:smoke rich,thick and strong burst.Moreover,irritating smoke was well controlled and gave the stronger sense of smoke satisfaction,which can improve the industrial availability of upper tobacco leaves.