Probe The Effects Of Associated Productiong Factors On NC55 Flue-cured Tobacco

Flue-cured tobacco NC55 is an important variety introduced from Shandong Province.In order to further determine the inherent attributes of NC55 varieties,and effectively solve the important technical problems of restricted cultivation system,this study carried out the relevant experiments that analyzed the characteristics of NC55 varieties in different transplanting time,fertilization conditions,planting density,mature harvest and curing characteristics.The results were as follows:1.Through the study on the occurrence and growth regulation of leaves,it was determined that the suitable transplanting time of NC55 was May 5~25,and the optimum transplanting time was May 10~15 in Weifang tobacco area.The average price and the percentage of fine tobacco were higher in above~mentioned transplanting time,and appropriately delay the transplanting time could improve the sensory evaluation quality of flue~cured tobacco.2.Among the N?P?K fertilizer,nitrogen was the main factor that affected the yield of NC55.In addition,the amount of applied phosphate fertilizer had the significant effect on the output value of NC55;Reducing the nitrogen application could increase the total sugar,reducing sugar content and the ratio of sugar to nicotine in tobacco leaves,decrease the total alkaloids,total nitrogen,potassium and the ratio of potassium to chlorine,and improve the sensory quality of tobacco leaf.When the amount of nitrogen application was same,the total sugar,reducing sugar content and the ratio of sugar to nicotine in tobacco leaf could increase first and then decrease,and the total alkaloids and total nitrogen could decrease first and then increase with increasing the ratio of top dressing proportion.The sensory quality of tobacco leaf could be improved by decreasing the ratio of nitrogen application from 90 kg/hm2 to 60 kg/hm2,and increasing the ratio of top dressing proportion to 50% ~70%.3.The application of soybean cake could increase the content of aroma components,the yield and output value of tobacco.Removing the cost of fertilizer,the output of 50% soybean cake nitrogen was highest.The sensory quality of flue~cured tobacco could be improved by appropriately increasing proportion of soybean cake,and the 50% soybean cake nitrogen and 100% soybean cake nitrogen treatments were best.Considering the cost of soybean cake,the effect of soybean cake application on the yield,output value,the ratio of soybean cake cost to output value,and the effect of soybean cake application on the quality of flue-cured tobacco,the best fertilizer application proposal was 50% soybean cake nitrogen ratio.4.Considering the appearance quality,main economic characters,main chemical composition content and proportion,and sensory quality of tobacco leaves after curing,the lower leaves were suitable to be harvested when the yellowing degree of leaves was set as 60~70%;the middle leaves were suitable to be harvested when the yellowing degree of leaves was set as 70~80%;and the upper leaves were suitable to be harvested when the yellowing degree leaves was set as 80~90%.5.From the dark box and curing test of different tobacco varieties,the easy and holding curing potential of Luyan No.1 were not ideal;while the easy and holding curing potential of NC55 were better,and during the intensive curing process,the characteristics of tobacco leaf yellowing and water loss were better.