【作者】 夏联利；

【导师】 岳彩鹏；

【作者基本信息】 郑州大学 ， 植物学， 2013， 硕士

【摘要】 烟草是我国重要的经济作物,其体内含有丰富的次生代谢产物,包括多糖、多酚、萜类等。茄尼醇是萜类的一种,四倍半萜烯醇,具有重大经济价值和医药价值。烟草包括任何一种植物整个生命期都处在一个动态变化的环境中,其生长发育以及次生代谢过程必然会受到自然环境和人为因素的影响。本文研究了光强、光质和稀土元素对烟草茄尼醇代谢和烟草生长发育的影响,结果如下：适当轻度遮荫,促进光合色素的形成,叶绿素a/b比值下降,提高烟叶的光合速率,增加烟叶中茄尼醇的含量；重度遮荫不利于光合色素合成,光合速率明显低下,影响烟草生长；分子水平检测显示了合成途径中关键酶-法尼基焦磷酸合酶基因(fps)表达的变化,但是和类萜茄尼醇合成积累的关系有待进一步研究。光质实验,长波长处理(红、黄光膜)促进叶绿素的形成,叶绿素a/b比值下降,提高叶绿素b含量,提高了烟叶的光合速率,增加了烟株的干物质积累,促进关键酶基因fps的表达,增加了茄尼醇产量。紫外光处理可以促进关键酶基因fps的表达,增加烟叶中茄尼醇含量,但紫外光不利于光合色素的形成,抑制光合速率和烟草生长,生物量产量较低。fps分子检测表明光质处理后期表达量明显高于前期,烟叶中茄尼醇含量并不与fps表达量完全一致。300-700μmol/L浓度的硝酸镧和100-500μmol/L浓度的硝酸铈对烟草处理一定程度上可以增加色素含量,改变叶绿素组成比例,增强光合速率,增加生物产量,并且显著提高了茄尼醇的含量。关键酶基因fps表达量则表明各浓度处理低于对照,稀土元素对茄尼醇代谢影响的分子机理有待进一步研究。更多还原

【Abstract】 Tobacco is an important economic crop in China, which produces various and abundant secondary metabolites including polysaccharides, polyphenols, terpenes and so on. Solanesol is a kind of polyterpene alcohol of great economic and medical value.Like other plants, tobacco goes though its life in a dynamically changing environment. The process of its growth and secondary metabolism is inevitably affected by natural and human factors. In this article, we investigated the effects of light intensity, light quality and rare earth elements on the growth and solanesol metabolism of tobacco.When reducing light intensity appropriately by mild shading, photosynthetic rate and the accumulation of photosynthetic pigments and solanesol were increased, while chlorophyll a/b ratio declined. Severe lack of light impaired photosynthetic rate, photosynthetic pigments and the growth of tobacco significantly. Farnesyl pyrophosphate synthase (FPS) gene (fps) expression was also detected by Real-Time PCR but the relationship between the solanesol synthesis and fps expression needs further study.Light quality experiment showed that long-wavelength light (red and yellow film shading) promoted the biomass accumulation, photosynthetic rate and chlorophyll content, but chlorophyll a/b ratio was decreased. In addition, solanesol production and fps expression increased as well under red and yellow film shading. UV radiation led to upregulation of fps and solanesol production, but not the photosynthetic rate and photosynthetic pigments. The expression level of fps was significantly higher in the late stage than the previous. However solanesol content and fps expression was not completely consistent.As rare earth elements, lanthanum nitrate (La(NO3)3) and cerium nitrate (Ce(NO3)3) treatment elevated photosynthetic rate, photosynthetic pigments, plant biomass and solanesol content under appropriate dose. When La(NO3)3and Ce(NO3)3 was applied with300-700μmol/L and100-500μmol/L respectively, solanesol content in tobacco leaf increased in a dose-dependent manner. Real-Time PCR analysis showed that rare earth elements attenuated fps expression.更多还原