Study On The Key Cultivation Techniques For Improving Tobacco Quality Of CB-1

CB-1 is a unique type of flue-cured tobacco in Sanming tobacco growing area of Fujian Province.Its excellent quality and fragrant style are deeply popular among tobacco industries.With nationalwide increasing demands on off-stock,compression of tobacco purchasing and sale market,cigarette enterprises start to put forward higher and higher requirements to tobacco leaves,which indicates that the transformation from "quantity assurance" to "quality premise" of tobacco leaf production and procurement standards are quite necessary.Under new situation,the production and growth of clear flue-cured tobacco exist several deficiencies:firstly,amount of nitrogen fertilization application is not accurate.Both insufficient or excessive applications of nitrogen fertilization can lead to the tobacco quality decline;secondly,there are many types of fertilizers and their release effects can influence the quality of cured tobacco leaves;thirdly,transplanting methods are quite many,which may lead great difference in field growth of tobacco plants;fourthly,it is not able to adjust topping timing in accordance with field fertility levels.In order to solve the problems mentioned above,this paper studies the key cultivation techniques for improving tobacco quality of CB-1 and makes researches from different aspects including nitrogen fertilization application amount,use of biological use of biological fertilizer and micro-fertilizer,various film coverage patterns and various topping,aiming to further promote the quality of CB-1 fragrant tobacco plants in Qingliu County.The main research results are as follows:1.When the application of pure nitrogen is controlled as 105kg/hm2,the growth of CB-1 tobacco in field will be better,and quality of flue-cured tobacco as well as economic characters will be higher.If the nitrogen application is too little,tobacco growing speed in later period will be slow and plant size can be small,together with low yields;but if the nitrogen application is too much,tobacco plants will have a higher risk of getting diseases in later period as well as declines in both financial characters and appearance quality at a certain degree.2.Through experiments,it shows that tobacco plants will grow better with faster speed of dry matter accumulation and higher yield and quality when applying 724 kg/hm2 humic acid bio-fertilizer for disposal(taking humic acid bio-fertilizer as base,among which 45 kg/hm2 combined with nutrient soil as hole fertilizers,and others applied to ditches).But since the effect of bio-fertilizers can be greatly influenced by climate and field conditions,it is suggested that the application volume of base fertilizer should be based on field moisture while rigging and climatic conditions of the current year,together with technical measures of water-fertilizer combination adjustment,so as to ensure the full use of fertilizers,promote the normal growth of tobacco plants and avoid the case of tobacco lack of fertilizers.3.The application of micro-fertilizer Saikun with amount of 30 bottles/hm2 has an obvious effect on promoting tobacco growth,field maturity degree and improving flue-cured tobacco appearance as well as inner quality,which can be taken as the auxiliary fertilizers in the actual production to enhance tobacco quality.4.Among all film coverage patterns,the performance of cultivation above films is better.The result shows that,tobacco cultivated above films has normal growing.period,stronger field growth,better performance in plant height and effective leaf numbers,higher proportion of superior flued-cured tobacco,higher output value per mu and better appearance quality.Compared with cultivation below films,the reason why cultivation above films is better is that,tobacco cultivated above films can get adequate air exchange and sufficient lighting conditions,which can promote the early and fast growth and sprout of tobacco plants,shorten the early growth stage,enhance the filed growth trend and satisfy the increasing requirements of tobacco for yield and quality.Besides,its actual operation is easier for tobacco growers to accept and take as the main coverage method of CB-1 plantlet transplantation.5.Through researches and experiments,conclusion can be drawn that under condition of 105 kg/hm2 nitrogen application amount,the tobacco plants which carry out topping at squaring stage are growing better,with optimal yield and quality and most harmonious intrinsic chemical composition.