杨春艳+刘飞+梁云峰+吉恒

摘要:利用傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)技术测定了成株期莴苣(Lactuca sativa L.var.angustana Irish)正常植株和霜霉病植株的叶片、食用茎、主根和须根4个部位的红外光谱。结果表明,两种植株叶片和食用茎中的主要成分均为蛋白质、多糖和脂类物质,须根中的主要物质成分为纤维素和木质素,正常植株主根中的主要成分是纤维素、木质素和脂类物质,霜霉病主根中的主要成分是纤维素、木质素和蛋白质;与正常植株相比,霜霉病植株叶片中蛋白质和多糖的组成或结构发生了变化,且脂类和多糖类物质相对含量有所增加,食用茎中蛋白质和脂类物质的相对含量均低于正常植株,而多糖类物质相对含量则高于正常植株,主根和须根中纤维素和木质素的相对含量均低于正常植株,但主根中木质素与纤维素的相对含量的则高于正常植株。FTIR可以区分霜霉病对莴苣植株不同部位的影响,有望为莴苣霜霉病的研究提供光谱信息。

关键词:莴苣(Lactuca sativa L.var. angustana Irish);傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR);霜霉病

中图分类号:S636.2;O657.3文献标识码:A文章编号:0439-8114(2014)10-2431-04

Analyzing Lettuce Downy Mildew with Fourier Transform Infrared Spectroscopy

YANG Chun-yan1, LIU Fei1, LIANG Yun-feng2, JI Heng3

(1.Department of Physics,Yuxi Normal University,Yuxi653100,Yunnan,China; 2.Agricultural Economics Management Service Centre of Yuanjiang,Yuanjiang653300,Yunnan,China;3.Tonghai No.2 Middle School,Tonghai652701,Yunnan,China)

Abstract:Fourier transform infrared spectroscopy (FTIR) was used to obtain the spectra of leaf, edible stem, taproot and fibrous roots of normal and downy mildew lettuce plants at the adult stage. The results showed that for normal and downy mildew lettuce plants, the main components of leaves and edible stem were protein, carbohydrates and lipids. For fibrous roots, the main components were cellulose and lignin. For taproots of normal plants,the main components were cellulose,lignin and lipids, but cellulose, lignin and protein were the main components of downy mildew plants. Relative to normal plants,the structure of carbohydrates and protein in leaves was changed. The relative content of lipids and carbohydrates increased. Protein and lipids in edible stems was decreased while carbohydrates was increased. Cellulose and lignin in taproot and fibrous roots were decreased. The ratio of the relative content of lignin to that of cellulose in mildew plants was higher than that in normal plants. It is indicated that FTIR could be used to study effects of the downy mildew on different parts of the lettuce, providing spectroscopy information for studying lettuce downy mildew.

Key words:lettuce(Lactuca sativa L.var.angustana Irish); fourier transform infrared spectroscopy; downy mildew

基金项目:云南省教育厅基金项目(2013Y480)

莴苣(Lactuca sativa L.var.angustana Irish)属菊科(Asteraceae)莴苣属(Lactuca),为一、二年生草本植物,是以莴苣中肥大茎部为食用部分的变种,含有较多的维生素及矿物质,营养丰富,是大众喜食的蔬菜之一。莴苣霜霉病俗称火风,是由莴苣盘梗霉(Bremia lactucae)引起的一种真菌性病害,是莴苣的主要病害之一[1]。幼苗发病后变黄枯死,成年株从下部老叶或成熟叶片开始发病,逐渐向上部叶片扩展。……