Study On The Selection Of High Quality Flue-Cured Tobacco Varieties And Its Supporting Cultivation Technology In Nanyang Tobacco Area

By field experiment,six high quality flue-cured tobacco varieties were used as materials to analyze the differences in agronomic traits,botanical traits,economic traits,appearance quality,content and sensory quality of each variety.The cultivation measures of qushou No.1,one of the varieties with good performance in various indicators,were studied in order to promote and produce Luzhou flavor flue-cured tobacco in Nanyang Tobacco Area Provide a theoretical basis.The experimental results show that:11.Selection of high quality and characteristic flue cured tobacco varieties in Nanyang Tobacco Growing AreaThe comprehensive agronomic characters of Yunyan 105,qushou 1 and Yunyan 99 were better than those of K326.Yunyan 87 and Yunyan 105 had stronger disease resistance,Yunyan 99 and Zhongyan 100 had poorer disease resistance,and qushou 1 had stronger resistance to Fusarium mycorrhizal rot.From the aspect of economic characters,Yunyan 87,Yunyan 105 and qushou 1 performed better in comprehensive economic characters.Among them,Yunyan 105 had the highest yield,Yunyan 87 had the highest output value,Yunyan 99 had the highest average price and proportion of superior tobacco,qushou 1 had excellent overall performance,all indexes were in the forefront,and K326 had the worst economic characters.From the chemical composition content and overall coordination,Yunyan 105 and qushou 1 were relatively good.The appearance quality of Yunyan 105 and qushou No.l was the best,followed by Yunyan 87,Yunyan 99,Zhongyan 100 and K326;almost all indexes of Yunyan 105 and qushou No.1 were equal to or better than the control,while Yunyan 99 was equal to or better than the control in color,leaf structure,identity,oil content and softness,and Zhongyan 100 was inferior to the control except luster.All indexes of K326 were inferior to or equivalent to the control.The rank of sensory quality evaluation scores was Yunyan 105,qushou No.1,Zhongyan 100,Yunyan 99,Yunyan 87 and K326,among which Yunyan 105 was higher than the control in all evaluation indexes,and the main reasons for its higher score were good aroma quality,sufficient aroma and good combustibility.Qushou No.1 was the best in aroma and convenience,Zhongyan 100 was the best in flammability,Yunyan 99 was the best in softness,and the sensory quality evaluation score of K326 was slightly lower than that of Yunyan 87.Qushou No.1 and Yunyan 105 have the potential to be planted in Nanyang Tobacco.2.Study on supporting cultivation measures of Nanyang Luzhou flavor flue cured tobacco variety qushou 1This study explored the effects of planting density,nitrogen application rate and leaf number on the growth,economic traits and quality of qushou No.1,and provided effective methods for further improving the yield and quality of tobacco and highlighting the strong flavor style of tobacco.Taking Flue-cured Tobacco Variety’qushou l’ as test material,according to L9(34)orthogonal test design,the above three factors were set at three different levels.The morphology and density of glandular hairs in different treatments were observed,and the secretion of glandular hairs on leaves was determined.The relative expression levels of cyc-1 and cyp71d16 genes related to the metabolism of cedrol in different treatments were determined by fluorescence quantitative PCR.The contents of Solanone and petroleum ether extract in flue-cured tobacco leaves of different treatments were compared,and the sensory quality was evaluated.The results showed that:planting density was the key factor affecting leaf area,economic traits,potassium and chlorine content of flue-cured tobacco leaves,nitrogen application rate was the key factor affecting root activity,economic traits and nitrogen alkali ratio of flue-cured tobacco leaves in group period and flourishing period,and the number of remaining leaves had the greatest influence on root activity in mature period,total sugar content,nicotine content and sugar alkali ratio of flue-cured tobacco leaves..Planting density was the key factor affecting the total density of glandular hairs,the content of leaf alkanes and the petroleum ether extract of flue-cured tobacco;the number of remaining leaves had the greatest impact on the content of Solanone;nitrogen application rate was the key factor affecting the total amount of cedrol,cedrol diol,leaf secretion,the relative expression of cyc-1 and cyp71d16 and sensory quality evaluation.Through the change of cultivation measures,we can promote the up-regulated expression of genes related to the metabolism of cemetride,increase the content of leaf secretion,and increase the content of petroleum ether extract and Solanone,so as to improve the sensory quality and further highlight the aroma style characteristics of tobacco leaves.