人参(Panax ginseng C.A.Meyer)锈腐病是由人参锈腐病菌[Cylindroc arpon de structans (Zinns.)Scholten]引起的根部病害之一,在人参生产中造成严重的产量损失.水杨酸(SA)是一种重要的化学诱导物质,目前将其应用于植物诱导抗病性的相关研究已成为热点.在温室可控条件下进行,用浓度为200mg·L-1的SA溶液处理2年生人参移栽苗,然后接种人参锈腐菌,接种后3,6,9,12,15,20,25,30d取样.通过测定参根内丙二醛(MDA)、脯氨酸、可溶性糖含量和细胞膜电解质外渗率,探索其诱导抗性的生理基础.结果表明:经SA处理后,接种人参锈腐菌的参根MDA含量在12d时较接菌未处理的下降了35.5％；脯氨酸含量在15d时达到峰值142.31μg· g-1FW,是清水对照的1.85倍；可溶性糖含量在12d时达到峰值4.91mg·g-1FW,是清水对照的1.6倍；细胞膜电解质外渗率呈明显下降趋势.这说明外源SA能有效降低参根内MDA含量和细胞膜电解质外渗率,提高脯氨酸和可溶性糖的含量,增强人参对锈腐病的系统抗性.%Ginseng rusty root rot caused by Cylindrocarpon destructans is the main disease which led to serious crop yield losses. It has been a new research issue in the induction of disease resistance elicited by salicylic acid which is an important resistance substance. Salicylic acid solution (200mg ? L"1) was used in the experiment. The ginseng plants were inoculated with Cylindrocarpon destructans and the samples of roots were obtained after 3, 6, 9, 12, 15, 20, 25 and 30 days in greenhouse. To illustrate the physiological mechanism of resistance induced by SA, the contents of MDA, proline, soluble sugar and relative electricity conductivity were measured. The results showed that the content of MDA of ginseng immersed in SA reduced by 35.5% at 12 days after inoculation. The content of proline reached the peak 142.3 lu,g-g"'FW at 15 days after inoculation, was 1.85 times of CK, and the content of soluble sugar reached the peak 4.91mg·g-1 FW at 12 days, was 1.6 times of CK. The relative electricity conductivity was on a declining curve. Therefore, SA treatment could effectively decrease the contents of MDA and relative electricity conductivity, but increase the contents of proline and soluble sugar. SA could induce the system resistance of ginseng to Cylindrocarpon destructans.
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