烤烟根系分泌物的分离鉴定及对种子萌发的影响

Identification of Chemical Compositions of Root Exudates from Flue-cured Tobacco and Their Influence to Seed Germination

为研究烤烟根系分泌物在烟草连作障碍中的作用,揭示主要烤烟品种根系分泌物的种类、数量及其对烟草生长的影响,对中烟100、NC89、K326中不同组分根系分泌物的主要成分进行了分离鉴定,并调查了中烟100不同组分根系分泌物对烟草种子发芽率和发芽势的影响。结果表明,3个品种根系分泌物主要是有机酸类,其中在中性提取条件下,含量较高的物质有2-羟基丙酸、肉豆蔻酸、新植二烯、东莨菪素、辛酸等;在酸性提取条件下,含量相对较高的物质有3-羟基丁酸、新植二烯、丁二酸、棕榈酸、肉桂酸等;在碱性提取条件下,含量相对较高的物质有新植二烯、棕榈酸、硬脂酸等。2-羟基丙酸、苯甲酸、丁二酸、烟碱、新植二烯、肉豆蔻酸、棕榈酸、延胡索酸等为3个烤烟品种根系分泌物的共有成分。中烟100不同组分根系分泌物对种子发芽率和发芽势的影响程度依次为:中性组分>酸性组分>碱性组分。延胡索酸、丁二酸、烟碱3种物质对烟草种子发芽率均有抑制作用,并且随着浓度的增加而逐渐加强。

In order to investigate the effects of root exudates on continuous tobacco cropping problem, three varieties of tobacco （Zhongyanl00, NC89, K326） were used to identify the root exudates in different extracting conditions, and the effects of root exudates of Zhongyan 100 in different extracting conditions on tobacco seed. The results show that, the root exudates in different extracting conditions of the three varieties mainly contained organic acids. Under neutral condition, the components of root exudates included 2-hydroxyl propionic acid, Tetradecanoic acid, Neophytadiene, Scopoletin and Octanoic acid. Under acid condition, the components of root exudates included 3-hydroxy butyrate, Neophytadiene, Succinic acid, Hexadecanoic acid and Cinnamic acid. Under alkaline condition, the components of root exudates included Neophytadiene, Hexadecanoic acid and Stearic acid. 2-hydroxyl propionic acid, Benzoic acid, Succinic acid, Nicotine,Neophytadiene, Tetradecanoic acid, Hexadecanoic acid and Fumaric acid were identified in the root exudates of all the three varieties of tobacco. The grade of influence by root exudates of Zhongyan 100 in different extracting conditions on tobacco seed were （from high to low）： neutral condition, alkaline condition and acid condition. Fumaric acid, Succinic acid and Nicotine had certain inhibition on the germination rate of the tobacco seeds. The germinating percentage of tobacco seed decreased with increasing dosage of these three compounds.