Effects Of Genotype And Nitrogen Fertilizeramount On The Quality And Sensory Evaluation In Flue-Cured Tobacco

The experiments were carried out to investigate the effects of genotype and nitrogen fertilizer quantity on the quality and sensory evaluation in flue-cured tobacco during 2009 and 2010 in Pingdingshan. The main results were summarized as follows:1,Study on the quality and sensory evaluation in different genotypes of flue-cured tobaccoThe growing stage,the plant height,the stem wai,the average leaf number,the node length of KRK26 and KRK28 were biggest in all varieties,the agronomic characters of NC297 and NC102 are equal to NC89 and zhong yan 100 (CK1 and CK2). KRK28 had the maximum yield,zhong yan100 had the maximum value and the highest proportions of top and middle class tobaccoLeaves, The yield and value were observed at variety NC297 were higher than NC89(CK1). NC297,KRK26,NC89 possessed the best outward appearance quality, the inherent quality and smoking quality are better than others varieties. The disease index against TMV and Black shank disease of 4 varieties were higher than NC89(CK1), KRK26 had the highest disease resistance in 6 varieties,NC89 had the worst disease resistance in 6 varieties.The results showed that the contents of Chromoplast Pigment decreased gradually during the mature period of flue-cured tobacco leaves;The content of aroma components degraded from chlorophyll and carotenoid were quite different among different genotypes of flue-cured tobacco leaves. Among all the nine flue-cured tobacco varieties, KRK28 had the highest content of degraded components of chlorophyll and carotenoid. There were significant differences both in the amount and rate of degradation of chromoplast pigments among genotypes. Correlation analysis showed that the positive correlations existed between the amount of degradation and the content of catabolites in flue-cured leaves for most of the components. The contents of the catabolite of KRK28,which had the higher degradation rate of the chromoplast pigment, are relatively rich than that of the other tobacco flue-cured varieties. The unique aroma style of flue-cured tobacco in different genotypes related with content of degraded components of chlorophyll and carotenoid. If degrade components of chlorophyll and carotenoid sufficiently content of degraded promote,it would be benefit to improve the aroma quality of tobacco leaves during maturing. It was in favor of enhancing the quality of aromatic matters if promting the degradation of chlorophyll and carotenoi during the process of maturation.Neutral aroma components in various tobacco leaves were basically the same, but the content vary. Total content of neutral aroma components of middle leaves varied from high to low was KRK28,NC72,NC71,KRK26,NC102,NC297,CC402,NC89,zhongyan100. The contents of products degraded by carotene,the products of browning reaction,the products of aromatic amino acid metabolism and the neophytadiene in KRK28 was higher,the products degraded by cembrane in NC297 was higher,while zhongyan100 was lower.2,Effects of variety and nitrogen fertilizer quatity on the quality and sensory evaluation in flue-cured tobacco leavesVariety and fertilization amount had great effects on the growth, yield and quality of flue-cured tobacco. The leaf size, percentage of high-grade cured leaves, average price and the output value were affected by both variety and fertilization amount. Along with the rise of fertilization amount, the growth and development of tobacco plant quickened, the yield increased, but the quality decreased. Among different varieties, KRK26 has the largest amount of dry matter accumulation, that of NC297 is large with the nitrogen fertilization amount less than 45kg·hm-2, more than 45kg·hm-2 KRK26 is the largest. With the rise of fertilization amount, the leaf size, weight per leaf, leaf thickness and leaf specific weight increased. The leaf size and weight per leaf of KRK26 and zhongyan100 is large and NC89 has the smallest stem content in lamina. Tobacco leaves with low- nitrogen fertilizer are thinner, organization is loose and have lighter color and less oil. With appropriate fertilizer thickness is moderate, organization moderate and has more orange color and oil. With high fertilizer leaves are thick, color slants dark, organization is close, oil is less than that of appropriate nitrogen fertilizer. Leaves of NC297 with 45kg·hm-2 nitrogen fertilizer have orange color, the best appearance quality, more oil, good flexibility and percentage of high-grade cured leaves and average price are the highest. Chemical composition coordination of NC297 with 22.5 and 45kg·hm-2 nitrogen fertilizer is the best, NC89 with 22.5 and 45kg·hm-2 nitrogen fertilizer rank second. Sensory evaluation of NC297 and KRK26 with 45kg·hm-2 nitrogen fertilizer are the best, both with 22.5kg·hm-2 nitrogen fertilizer are better, NC89 and zhongyan100 with 90kg·hm-2 nitrogen fertilizer are the worst.Considering all the factors, for all varieties fertilize 45kg·hm-2 nitrogen have the highest output, perfect yield, orange color, more oil and good flexibility, inner quality and sensory evaluation are the best.3,Effect of regulated deficit nitrogen application on quality and sensory evaluation at maturity of flue-cured tobaccoBased on experiment in tobacco through pot experiments, the five nitrogen application levels were designed to study the effect of regulated deficit nitrogen application on growth and quality at maturity of flue-cured tobacco. The results showed that with the decreasing regulated deficit nitrogen application, the leaf area, leaf weight, contents of plastid pigments, total nitrogen and nicotine in tobacco leaf were increased;severe deficit nitrogen application(100%) had retarding effects on leaf growth, yield and quality. While for treatments with mild deficit nitrogen application(25% and 0) could lead to leaf late-maturing, make its chemical components were inharmonious. Results showed that treatments of moderate deficit nitrogen application (75% and 50%)were advantageous to leaf growth, chemical components and quality formation of flue-cured tobacco leaves. High contents of neophytadiene,carotenoid catabolites,aromatic amino acid metabolism,petroleum ether extracts were found for treatments of moderate deficit nitrogen application. From sensory evaluation, we can conclude that the quality of sensory in treatments of moderate deficit nitrogen application tobacco leaves was best, and the style of strength flavor type also was significant.