摘要
选择抗感水稻品种 ,就 5个不同部位对纹枯病菌 ( Rhizoctonia solani)侵染的反应及其机理进行了研究。结果表明 :接种 5d后叶鞘内侧的病斑扩展最快 ,其次是叶片和叶鞘外侧 ,叶片基部仅在边缘叶肉细胞产生褐色短线条斑 ,叶枕则不发病。不同部位表面蜡质含量测定表明 :叶鞘内侧蜡质含量最低 ,仅为 0 .0 0 97mg/cm2 ;叶枕部最高 ,为 0 .61 4 4mg/cm2 ,是叶鞘内侧的 63.3倍。通过电镜观察看出 ,叶鞘内侧表皮细胞光滑、无硅化细胞存在 ;叶片和叶鞘外侧硅化细胞小而稀疏 ;叶片基部和叶枕的硅化细胞大而密。此外 ,叶枕部角质层最厚 ,达 7.60 μm;其次是叶片、叶鞘外侧和叶片基部 ;叶鞘内侧角质层最薄 ,只有 1 .1 2 μm。
The reaction of five parts of two rice varieties (Lemont and Jasmine 85) to the infection of Rhizoctonia solani and the resistant mechanism was preliminarily studied. The inoculation tests indicated that the lesion was fast spread on the inside of leaf sheath, and slowly on leaves and the outside of leaf sheath. Short, brown stripe was only formed on the margin of leaf base. But no spot was produced on leaf pulvinus. The biochemical analyses showed that epicuticular wax in leaf pulvinus was much more than in the inside of leaf sheath, and the former (0.614 4 mg/cm 2) was 63.3 times the latter (0 009 7 mg/cm 2). The scanning electron microscopic observations revealed that silicificated cells were big, dense on leaf pulvinus and leaf base, and small, sparse on leaves and the outside of leaf sheath, and that no silicificated cells existed on the inside of leaf sheath. Furthermore, the cuticle of leaf pulvinus (7.60 μm) was significantly thicker than that of the inside of leaf sheath (1.12 μm).
基金
"九五"国家农业攻关项目! (96 0 14 0 10 6 0 1)
