草地早熟禾派伦霉叶枯病病原菌的分离、致病性测定及鉴定

Isolation,pathogenicity determination and identification of leaf blight pathogens of Poa pratensis

摘要:

【目的】鉴定草地早熟禾（Poa pratensis）叶枯病。【方法】对草地早熟禾叶枯病症状进行描述， 并利用形态学特征及分子生物学方法对病原进行鉴定。【结果】早熟禾叶枯病主要危害中上部叶片，常在叶尖和叶缘开始发病，逐渐向内扩展，形成较大枯死斑，病斑上形成大量小黑点。病原菌在 PDA 培养基上初呈白色，后变成橄榄绿和暗褐色，产生橘黄颗粒状液滴，背面有轮纹；菌丝有隔膜，无色或淡褐色；分生孢子多为长椭圆形，单胞无色，两端含油球，大小为 4. 2 μm×1. 8 μm~7. 7 μm×4. 8 μm（平均值 5. 8 μm×3. 4 μm）；分生孢子器呈卵球形、长椭圆形或球形，大小为 48. 3 μm×193. 1 μm~38. 5 μm× 139. 6 μm（平均值 106. 0 μm×86. 4 μm）。【结论】根据形态学特征和 ITS 基因序列分析，将病原鉴定为 Peyronellaea glomerata，将该病害鉴定为早熟禾派伦霉叶枯病。该研究结果为早熟禾叶枯病的诊断和综合防治奠定了基础。

Abstract:

【Objective】 To identify leaf blight of

in Lanzhou.【Method】 The symptoms of P. pratensis leaf blight in Lanzhou grassland were described，and the pathogen was identified by morphological characteristics and molecular biology methods.【Result】 Leaf blight of P. pratensis mainly affects the middle and upper leaves， often starting at the tip and leaf edge，gradually expanding inward，forming large dead spots，and forming a large number of small black spots on the spots. The pathogen was initially white on PDA medium，then turned to olive green and dark brown，and produced orange granular droplets with wheel markings on the back. All the mycelium had diaphragm，which was colorless or light brown. The conidia shape was long ellipsoidal neurons，which was single cell （colorless） and had oil balls at both ends. The size of conida was 4. 2 μm×1. 8 μm~7. 7 μm×4. 8 μm （average 5. 8 μm×3. 4 μm）. The pycnidium shapes was globose，ovoid or oblong，even with orifice，and the sizes ranged from 48. 3μm×193. 1 μm to 38. 5 μm×139. 6 μm （average 106. 0 μm×86. 4 μm）.【Conclusion】 The pathogen of P. pratensis leaf blight disease was identified as Peyronellaea glomerata that combined with its morphological characteristics and ITS sequence analysis. These results provided the basis for the diagnosis and comprehensive control of P. pratensis leaf blight disease.