嫁接茄根系分泌物与抗黄萎病的关系及其组分分析

Relationship between root exudates of grafted eggplants and Verticillium wilt resistance and their components identification

探讨了嫁接对茄子土传病害黄萎病抗性的影响,采用浸根法收集茄子根系分泌物,并利用气-质联用技术检测了根系分泌物的组分和含量,测定了茄子根系分泌物及其模拟化感物质对黄萎菌菌丝生长的化感作用,分析嫁接后茄子根系分泌物的组成差异,探讨了嫁接茄抗病性与其根系分泌物成分的关系。结果表明:嫁接使茄子发病率显著降低。土壤黄萎菌数量随发育时期的推进而显著低于自根茄。嫁接茄根系分泌物对黄萎菌菌丝生长有一定的抑制作用。GC-MS检测结果显示,嫁接换根使茄子根系分泌物的组成成分发生一定的改变,嫁接根系分泌物中检测到了烃类、酯类、醇类、酚类、酮类、苯类和胺类物质,其中苯、醇和胺类在ZG中未检测到。但嫁接茄也缺少自根茄中检测到的炔类和菲啶。酚类公认的化感物质含量表现出自根茄大于嫁接茄。模拟物质对黄萎菌菌丝生长的影响表明:邻苯二甲酸二丁酯表现出在0.05 0.5 mmol.L-1浓度范围随浓度增加抑制作用增强,后随浓度增加抑制作用有所减弱。而豆蔻酸和棕榈酸均表现出随浓度增加先促进后抑制黄萎菌菌丝的生长。

Effect of grafting on soil-borne disease（Verticillium wilt） resistance of eggplants was studied in this paper.The root exudates of grafted eggplants were collected with root soaking method.Components and contents of root exudates of grafted eggplants were determined by Gas chromatography/mass spectrometry,and the components′ variation of root exudates by grafting was analyzed.Effects of root exudates and their simulated allelochemicals on mycelium growth of Verticillium dahliae were studied.The relationship between root exudates of grafted eggplants and their resistance to Verticillium wilt was discussed.The results showed that grafted eggplants showed a decrease of disease incidence of Verticillium dahliae.The amounts of Verticillium dahliae in soil were significantly lower in grafted eggplant treatment than in self-rooted eggplant treatment with the development of eggplants.Mycelium growth was also inhibited by the root exudates of grafted eggplants.GC-MS analysis indicated that grafting changed the components of root exudates of eggplants.Hydrocarbon,ester,acohol,phenol,ketone,benzene and amine were detected in the root exudates of grafted eggplants,while acohol,benzene and amine were not in the root exudates of self-rooted eggplants.Alkyne and phenanthridine were detected in the root exudates of self-rooted eggplants,but not in grafted eggplants.The content of phenol（a allelochemical） in root exudates was lower in grafted eggplant treatment than in self-rooted eggplant treament.Effects of simulated root exudates of eggplants on mycelium growth of Verticillium dahliae showed that inhibitory effect of dibutyl phthalate on mycelium growth of Verticillium dahliae increased at concentrations ranging from 0.05 0.5 mmol·L^-1,and reduced at the higher concentration.Inhibitory effects of tetradecanoic acid and hexadecanoic acid exhibited a decrease trend at the lower concentration range and an increase at the higher concentration range.