烟草叶片对不同光质短期应答的代谢轮廓

Metabolic profiling of the short-term responses of Nicotiana tabacum leaves cultivated under different LED lights

在烟草上部叶片生理成熟期给以白、紫外A、蓝、绿、黄、红6种LED灯光处理,研究了烟草叶片对不同光质的短期应答.结果表明:采用非靶标检测方法共检测到68种GC/MS(气相色谱/质谱)稳定的代谢产物,在PLS-DA得分图中,6种光处理的样品被明显分开;有61种在质谱库中得到鉴定,其中45种代谢物质含量在不同光处理间存在显著性差异,主要为有机酸类、糖类、TCA循环中间产物、氨基酸类等初级代谢产物;采用差异性代谢物的热力图及聚类分析将其分为5类,同时也将6个处理明显分开,其中红、蓝光处理差异最为明显,除B类物质外,其他4类均以红光处理高于蓝光处理.采用靶标性检测方法测定了3种生物碱、5种多酚及茄尼醇的含量,4种(加上非靶标测定到的烟碱)生物碱在不同光质处理间的变化趋势一致红光和黄光明显促进了生物碱积累;莰菲醇基芸香苷和芸香苷在不同处理之间的变化趋势一致,以蓝光处理最低、黄光最高,光质对其他3种多酚的影响备异;黄光明显抑制了茄尼醇的积累蓝光处理的叶片中茄尼醇含量最高.说明光质变化对烟草脂肪酸代谢、糖代谢、生物碱代谢、氨基酸代谢、TCA循环和莽草酸途径等多条代谢途径均有显著的影响.

The physiologically mature tobacco（Nicotiana tabacum） leaves was exposed to different light-emitting diode（LED） lights,i.e.ultraviolet A（UV-A）,blue,green,yellow,red,white,to investigate their short-term response.Results showed that：1） 68 GC/MS-stable metabolites were detected by non-targeted method.In the PLS-DA score plot,tobacco leaf samples showed clear grouping in each light cultivating condition.61 metabolites were identified in mass spectra library.Besides,45 metabolites,mainly including organic acids,carbohydrates,TCA cycle intermediate metabolites and amino acids,showed significant differences among the six light treatments.Hierarchical cluster analysis（HCA） and heat map showed that differential metabolites could be divided into five groups,and there were significant differences among the six treatments,especially under red and blue lights.Except for the metabolites of group B,almost all other metabolites contents in tobacco leaves treated with red light were higher than those under blue light.2） Contents of solanesol,3 alkaloids and 5 polyphenols were measured with targeted method.4 alkaloids,including nicotine detected by non-targeted method,showed similar variation among all treatments,of which red and yellow light increased alkaloid accumulation significantly.The kaempferol-3-O-rutinoside and rutin showed similar variation among the six treatments,with the lowest content under blue light and the highest content under yellow light,nevertheless,3 other polyphenols were differently affected by light qualities.The aolanesol accumulation was significantly repressed by yellow light,but showed highest content under blue light.In conclusion,light quality affected many metabolic pathways significantly in tobacco,such as fatty acid metabolism,glycometabolism,alkaloid metabolism,amino acid metabolism,tricarboxylic acid cycle and shikimate pathway.