安徽省水稻穗腐病病原鉴定及生物学特性研究

Identification and characterization of Rice Spikelet Rot Disease pathogens in Anhui Province

水稻穗腐病（rice spikelet rot disease,RSRD）是由多种病原菌引起的复合性病害,近年来上升成为影响水稻产量和品质的一种重要穗部病害。对安徽省穗腐病危害分布进行调查,采集病样分离病原物并进行形态学和分子鉴定,研究了其生物学特性。结果表明,引起水稻穗腐病的病原菌主要有4种,分别为层出镰刀菌（Fusarium proliferates）、新月弯孢菌（Cartularies lunatics）、稻黑孢菌（Nigrospora oryzae）和细交链格孢菌（Alternaria tenuis）,其致死温度分别为60、59、59和60℃（10 min）;菌丝生长温度均为10-35℃（最适20-30℃）,pH值为5-9（最适7）;孢子萌发温度均为5-45℃（最适25-35℃）,pH值为4-8（最适7）;最适碳源为葡萄糖和淀粉,最适氮源为硝酸钾、尿素和脯氨酸。在长江流域和淮河流域水稻种植区,主要病原菌种类分布存在差异。

Rice spikelet rot disease （RSRD）, caused by a number of parasitical and saprophytic pathogens,has become the most important disease affecting rice yield and quality in recent years. This study was to identifythe RSRD pathogens and their distribution in Anhui Province. The pathogenic bacteria were identified as Fusa-rium proliferates, Cartularies lunatics, Nigrospora oryzae, and Alternaria tenuis based on the morphologicalcharacteristics and ITS sequence and their lethal temperatures were 60, 59, 59, and 60℃ for 10 minutes, respec-tively. The suitable temperature and pH for the mycelial growth of all four bacteria were 10-35℃ （optimum at20-30℃） and pH 5-9 （optimum at pH 7.0）, respectively. The temperature and pH suitable for the conidial germi-nation were 5-45℃ （optimum at 25-35℃） and pH 4-8 （optimum at pH 7.0）, respectively. For these pathogenicbacteria, dextrose and starch were suitable C-sources and KNO3, urea, and proline were suitable N-sources. Theresearch also showed the difference in pathogen type and distribution of RSRD in the rice regions of YangtzeRiver basin and Huaihe River basin.