Factor Inducing Hypersensitive Resistance of Rice Plants to Blast Fungus, Pyricularia oryzae

水稻植株对稻瘟病菌过敏抗性的诱导因素

• 批准号: 07660012
• 负责人: NOMURA Kazunari
• 金额: $ 1.34万
• 依托单位: Nihon University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07660012/
• 关键词: Rice Blast; Culture Cells; Hypersensitive Reaction; Necrosis; Elicitor; Oryza sativa; Oryza satira; イネいもち病; ネクロシス誘導

Localized cell death and activation of phenylpropanoid metabolism in suspension-cultured rice cells are induced by factors secreted by blast fungus. Microscopic observation revealed that the death of cells at the periphery of calli appeared within 1 h after addition of a TCA-precipitable fraction (TCAp) of the fungus culture filtrate. The number of dead cells continued to increase for up to 24 h, followed by general browning of the calli after about 48 h. However, the culture still contained uninjured cells within the callus clumps, and there was no significant difference in culture viability from non-treated callus. Phenylalanine ammonia-lyase (PAL) and peroxidase (POX) activities were induced by TCAp and reached a maximum at 6 h and 1-2 days after treatment, respectively. No cultivar-race specificity was found in PAL activity of cultured cells induced by TCAp. Phenolic compounds were found in callus tissue treated with TCAp. Among these phenolic compounds, accumulation of p-coumaric acid was remarkable. Fractions of fungal culture filtrate obtained by C_<18> reverse-phase chromatography were assayd for the ability to induce cell browning, PAL activity in cultured cells : Among the individual fractions, that which had the most potent activity to induce browning stimulated PAL activity.

水稻悬浮培养细胞的局部死亡和苯丙烷类代谢的激活是由稻瘟病菌分泌的因子诱导的。显微镜观察发现，在加入真菌培养滤液中的三氯乙酸可沉淀部分(TCAP)后1h内，愈伤组织边缘出现细胞死亡。随着培养时间的延长，死亡细胞数持续增加，48h左右愈伤组织基本褐化，但愈伤组织块内仍含有未损伤的细胞，培养活力与未处理的愈伤组织无显著差异。TCAP诱导苯丙氨酸解氨酶(PAL)和过氧化物酶(POX)活性，分别在处理后6h和1~2d达到最大值。TCAP诱导培养细胞PAL活性无品种-小种特异性。在TCAP处理的愈伤组织中发现了酚类化合物。在这些酚类化合物中，对香豆酸的积累显著。用C&lt；18&gt；反相色谱分离得到的真菌培养滤液组分具有诱导细胞褐变的能力，并对培养细胞的PAL活性进行了测定，其中诱导褐变活性最强的组分对PAL活性有刺激作用。