Harpin_(Ea)和BTH诱导厚皮甜瓜抗菌物质的研究

Study on antifungal substances induced by Harpin_(Ea) and BTH in muskmelons

分别以50mg.L-1 Harpin和100mg.L-1 BTH处理厚皮甜瓜,研究诱抗剂对植物生长期间抗菌物质合成的影响。叶片中抗菌物质用甲醇-二氯甲烷浸提,薄层层析色谱(TLC)分离,并以链格孢(Alternaria alternata)为指示菌,对其抑菌带的抗菌物质进行气相色谱-质谱(GC-MS)联用分析。结果表明:甜瓜叶片中含有邻苯二甲酸二异丁酯、邻苯二甲酸二(2-乙基)己酯、邻苯二甲酸二丁酯、1,3,5-环庚三烯、9,12,15-三烯十八酸等多种预存抗菌物质;经Harpin或BTH诱抗剂处理后,抗菌物质的种类和含量均显著增加。诱抗剂处理不仅可诱导甜瓜植株上述固有抗菌物质含量的增加,而且还可诱导合成新的棕榈酸、棕榈酸甲酯、9,12,16-三烯十八醛、邻苯二甲酸丁酯等多种可能的抗菌物质。Harpin或BTH处理可以限制二孢白粉菌(Erysiphe cichoracearum)菌丝在叶片中的扩展,显著降低甜瓜白粉病和霜霉病的田间病情指数。

Muskmelon （cv. Yindi） seedlings were sprayed with 50 mg · L^- 1 Harpin and 100 mg · L^- 1 BTH, respec- tively, to study the effects on the synthesis of antifungal substances during growth period. Antifungal compounds in leav- es were used with methanol-dichlormethane and separated by thin layer chromatography （TLC）. Alternaria alternata was regarded as indicator fungus. Antifungal compounds in inhibition zones were identified by Gas Chromatography and Mass Spectrum （GC-MS）. The result indicated that some kinds of preformed antifungal compounds existed in leaves of musk- melon, such as bis （2-methylpr） 1,2-benzenecarboxylic acid, bis （2-ethylhexyl） dioctyl ester, 1,2-benzenedicarboxylic acid, dibutyl ester, 1,2-benzenecarboxylic acid, methyl ester and 9,12,15-octadecatrienoic acid. The species and contents of antifungal compounds significantly increased by elicitor treatments that could induce not only innate antifungal com- pounds but also novel antifungal compounds. Both Harpin and BTH could restrain Erysiphe cichoracearum expansion in leaves and could significantly decrease disease index of powdery mildew and downy mildew in muskmelon.