盆栽试验中施用外源生长调节剂对烤烟TSNAs生物合成的影响  

Effects of exogenous growth regulators on biosynthesis of tobacco-specific Nnitrosamines(TSNAs) in flue-cured tobacco by pot experiments

作　　者：王亚宁[1] 张翔[1] 刘腾飞[2] 李亮[1] 毛家伟[1] 司贤宗[1] 索炎炎[1] 余琼[1] WANG Yaning;ZHANG Xiang;LIU Tengfei;LI Liang;MAO Jiawei;SI Xianzong;SUO Yanyan;YU Qiong(Institute of Plant Nutrition and Agricultural Resources and Environmental Science,Henan Academy of Agricultural Sciences,Zhengzhou 450002,China;China Tobacco Hubei Industrial Co.,Ltd.,Wuhan 430051,China)

机构地区：[1]河南省农业科学院植物营养与资源环境研究所,郑州市金水区花园路116号450002 [2]湖北中烟工业有限责任公司

出　　处：《烟草科技》2018年第8期35-41,共7页Tobacco Science & Technology

基　　金：国家烟草专卖局科技计划项目"烟叶减害综合配套技术研究与应用"(110201002020);河南省烟草业转型升级科技攻关项目"河南植烟土壤保育技术研发及模式构建与示范"(2018410000270036)

摘　　要：为明确外源生长调节剂Z5[由生长素(IAA)、水杨酸(SA)和萘乙酸(NAA)配置而成]影响烟草特有亚硝胺(Tobacco-specific N-nitrosamines,TSNAs)生物合成的生理机制,在湖北省恩施土家族苗族自治州建始县试验基地设置叶面喷施Z5盆栽试验,以清水为对照,分析了烟株硝酸盐与亚硝酸盐含量(质量分数)、硝酸还原酶(NR)与烟碱合成关键酶活性的动态变化以及相关基因的表达量,并测定了烤后烟叶TSNAs和常规化学成分含量(质量分数)。结果表明,烤烟打顶后喷施Z5的烟叶TSNAs含量显著降低,上部叶和中部叶中TSNAs含量降低幅度分别为20.1%和12.4%,而烟叶化学成分含量在适宜范围内。外源生长调节物质降低TSNAs含量的作用机制,一是下调了控制NR活性的基因NR的表达,烟株打顶后第1天NR基因的相对表达量下调55.0%,NR活性受抑制,导致硝酸盐向亚硝酸盐的转化减少,叶片中亚硝酸盐的积累量降低;二是下调了控制烟碱合成关键酶基因的相对表达量,烟株打顶后第1天ADC、QPRT、ODC及PMT基因相对表达量分别下调82.1%、69.8%、91.8%和76.0%,使烟碱合成关键酶活性降低,从而减少了烟碱的合成,上部叶和中部叶烟碱含量下降幅度分别为23.5%和22.9%。To study the effects of exogenous growth regulator Z5 （IAA＋NAA＋SA） on the biosynthesis of tobacco-specific N-nitrosamines （TSNAs）, tobacco leaves were sprayed with Z5 （water as the control） by pot experiments in Jianshi County and Enshi City in Hubei Province. The dynamic variations of nitrate and nitrite contents, the activities of NR（nitrate reductase） and key enzymes related to nicotine synthesis, and the expressions of related genes were analyzed. The TSNA contents and routine chemical components in cured leaves were determined. The results showed that TSNA contents in leaves sprayed with Z5 after toping significantly reduced by 20.1% and 12.4% in upper and middle leaves, respectively. However,the contents of chemical components in leaves were in an appropriate range. The mechanism of Z5 to reduce TSNA contents were two： 1） The expression of NR which controlled NR activity was down-regulated by 55.0% on the 1st day after topping. The conversion of nitrate to nitrite decreased due to the inhibition of NR activity, then the accumulation of nitrite reduced. 2） The expressions of key genes （ADC, QPRT, ODC, and PMT） related to nicotine biosynthesis were down-regulated by 82.1%, 69.8%, 91.8% and 76.0% on the 1st day after topping respectively, which resulted in the reduction of key enzymes＇ activities in nicotine synthesis. Finally the synthesis of nicotine was inhibited. Nicotine contents in upper and middle leaves decreased by 23.5% and 22.9%, respectively.

关 键 词：烤烟 外源生长调节物 烟草特有亚硝胺 烟碱 亚硝酸盐 

分 类 号：S572.01[农业科学—烟草工业]