不同成熟度烤烟萜类物质含量及相关基因研究

Study on the Content of Terpenoids and Related Genes in Flue-cured Tobacco with Different Maturity Levels

为探究不同成熟度烤烟萜类物质代谢规律及与烟叶内在品质的关系,以中烟100为试验材料,采用实时荧光定量PCR(qRT-PCR)技术对萜类物质合成与降解关键基因表达量进行测定,利用气-质联用仪(GC-MS)检测烤后烟叶萜类物质及其降解产物,同时对烟叶感官质量进行评价。研究结果显示,随着成熟度的增加,烟叶腺毛脱落加剧,类胡萝卜素降解关键基因PAL表达量呈上升趋势,类胡萝卜素含量逐渐下降;西柏烷类物质含量与相关基因DXR、CYP71D16、C4H、CHS表达量变化趋势基本一致,整体呈现“先升后降”,并在完熟期达到高峰。中、上部烟叶均以完熟烟叶的感官质量评价最优,与萜类物质合成及相关基因表达上调密切相关,起到了柔和烟气、提质增香的作用。生产上中烟100宜在成熟采收基础上推迟5~7d,使烟叶成熟度达到完熟,可有效提高中上部烟叶内在品质及工业可用性。

In order to explore the relationship between the biosynthesis and catabolism of terpenoids in flue-cured tobacco of different maturity levels and the intrinsic quality of tobacco leaves,using Zhongyan 100 as the test material,real-time fluorescence quantitative PCR(RT-PCR)technology was used to measure the expression levels of key genes for terpenoid synthesis and degradation,and gas chromatography-mass spectrometry(GC-MS)detection technology was used to detect terpenoids and their degradation products after modulation and processing.At the same time,the smoking quality of tobacco leaves was evaluated.The results showed that as maturity increased,the shedding of glandular hairs intensified,the content of carotenoids and the expression level of PAL gene increased gradually;The content of siberians and genes expression level of DXR,CYP71D16,C4H,CHS showed a“increase first and then decrease”trend,and reached the peak during the ripening period.The sensory quality evaluation of the fully mature tobacco leaves in the middle and upper parts was the best.Maturation was found to be closely related to the upregulation of gene expression related to the synthesis of terpenoids,playing a role in softening smoke and improving quality and aroma.In tobacco production,it is recommended to further delay the harvest of tobacco leaves by 5-7 days on the basis of mature harvest,so that the maturity of the tobacco leaves can reach fully maturity,which can effectively improve the intrinsic quality and industrial usability of middle and upper tobacco leaves.