Screening And Evaluation Of Excellent Flue-cured Tobacco Varieties In Jiahe County

The paper was analysis comprehensively physiological and biochemical characteristics,dry matter accumulation,disease resistance,economic characteristics and quality by field test with 5 tobacco varieties were selected(Yun87 as control)under the Jiahe county eco-climatic conditions.The objective of the paper was preliminary screened suitable tobacco varieties in the Jiahe ecological conditions,which was provided a theoretical basis for the introduction of improved new tobacco varieties in Jiahe county,and realized fast and sustainable development of tobacco in Jiahe area.The results were shown as follow:1.Carbon&nitrogen metabolism in the seedling stage,the highest of the activity of levansucrase was the NC-71,the next was CZ-43 and Xiangyan 4;the nitrogen metabolism of CZ-43,NC-71 was better with the application of nitrogen fertilizer,the worst was Yueyan 98 and NC-297.Highest dry matter accumulation was Xiangyan 4 in 0-35days after transplanting;dry matter accumulation increased sharply in 35-50 days after transplanting,that of NC-297 was highest,next to Xiangyan-4 and Yunyan87;dry matter accumulation increased progressively in 50-65days after transplanting,that of NC-297 was heaviest,that of Yunyan87 was the minimum.2.All tested tobacco varieties(lines)in Jiahe region were susceptible to varying degrees of black shank and mosaic disease,and had good resistance to other common diseases.That of Xiangyan-4 and Yueyan98 had weakest resistance to black shank and mosaic disease.Others varieties was better performed with Yunyan 87.3.Comprehensive evaluation of economic traits of CZ-43 was the best,such as tobacco yield value,median,upper-middle proportional leaves.Comprehensive evaluation of yielding ability and reliability in the CZ-43 and NC71 performed best with the yi'elding ability and reliability,which had higher location interaction effects and small variance,the worst were Yueyan98,the others performed generally.Chemical composition of comprehensive assessment in the CZ43?NC71 got 85 points or more in the upper leaves,90 points or more in the central leaves,which had outstanding performance.Only Yueyan98 got lower score than the control Yunyan87.Based on the overall performance of each species in the Jiahe ecological zones,the paper suggested CZ-43 and NC71 was suitable for the Jiahe tobacco area,which provide a scientific basis and reference for replacement and rational distribution of flue-cured tobacco varieties.