Ren Xia, He Xiaofeng, Zhang Zhongfeng, Yan Zhiqiang, Jin Hui, Li Xiuzhuang, Qin Bo
Key Laboratory of Tobacco Diseases and Insect Pests Monitoring Controlling and Integrated Management, Institute of Tobacco Research, Chinese Academy of Agricultural Sciences , Qingdao 266101, People's Republic of China.
J Agric Food Chem. 2015 Oct 21;63(41):8975-80. doi: 10.1021/acs.jafc.5b03086. Epub 2015 Oct 9.
Autotoxicity, defined as a deleterious allelopathic effect among individuals of the same plant species, is considered as one of the factors that contributes to replant failure. Tobacco, as an important cultured and economic crop over the world, has been often hampered by replant failure. In view of the seriousness of this problem, the allelochemicals of flue-cured tobacco and their allelopathic effects were investigated. The extracts of rhizosphere soil exhibited phytotoxic activities against Lactuca sativa and autotoxic activities against tobacco itself. Bioassay-guided fractionation of the extract led to the isolation of six compounds, the structures of which were elucidated by spectroscopic analysis. Among them, β-cembrenediol (1), di-n-hexyl phthalate (2), and bis(2-propylheptyl) phthalate (3) showed observably phytotoxic activities against L. sativa seedlings and autotoxic activities on tobacco. The allelochemicals were then verified in the root zone soils of flue-cured tobacco by high-performance liquid chromatography (HPLC). These results provide new insights into the allelopathic mechanisms involved in the replant failure of flue-cured tobacco.
自毒作用被定义为同一植物物种个体之间有害的化感效应，它被认为是导致连作失败的因素之一。烟草作为全球一种重要的栽培经济作物，常常受到连作失败的困扰。鉴于这个问题的严重性，对烤烟的化感物质及其化感效应进行了研究。根际土壤提取物对生菜表现出植物毒性活性，对烟草自身表现出自毒活性。通过生物测定导向的提取物分离得到了六种化合物，其结构通过光谱分析得以阐明。其中，β-金合欢二醇（1）、邻苯二甲酸二正己酯（2）和邻苯二甲酸双（2-丙基庚基）酯（3）对生菜幼苗表现出明显的植物毒性活性，对烟草表现出自毒活性。然后通过高效液相色谱法（HPLC）在烤烟根际土壤中验证了这些化感物质。这些结果为烤烟连作失败所涉及的化感机制提供了新的见解。
