不同寄主来源的串珠镰孢生物学性状及其在无性后代的遗传与变异

自安徽、山东、湖北、江苏等地多点采集棉花红腐病、水稻恶苗病、玉米穗腐病的病组织，经分离、鉴定和纯化，获得107个串珠镰孢（Fusarium monilifoFine）菌株。对上述来源于棉花、水稻、玉米的串珠镰孢的菌落形态、生长速率和产孢量等生物学性状及其在无性后代的遗传与变异进行了研究。结果表明，不同寄主来源的串珠镰孢菌株的菌丝生长温度范围和最适温度大致相同，但在菌落形态特别是色素方面存在明显差异，生长速率和产孢量也存在显著差异。棉花菌株的平均生长速率最大，玉米菌株生长速率最小，水稻菌株生长速率居中，相同群体的不同菌株间生长速率有极显著差异；玉米菌株产孢量最大，棉花菌株产孢量最小，水稻菌株产孢量居中。方差分析显示，不同寄主菌株群体间产孢量存在显著差异，而同一寄主群体的不同菌株间产孢量均无显著差异，说明菌株产孢量大小主要与其寄主种类有关，而与地区来源关系不大。遗传测定结果表明，分离自棉花、玉米和水稻的串珠镰孢的菌落形态和生长速率在单分生孢子后代均可稳定遗传；产孢量性状遗传有两种情况：分离自棉花和水稻的串珠镰孢菌株Fm1和Fm31的产孢量性状在单分生孢子后代均可稳定遗传，而分离白玉米的串珠镰孢菌株Fm19的产孢量性状在单分生孢子第一代（CG1）发生变异。

The Biological Characters and their Inheritance and Variation of Fusarium moniliforme Isolates from Different Hosts

The studies were conducted to determine the difference among Fusarium moniliforme isolates from different hosts in the biological characters, to explore the relationship between the biological characters of F. moniliforme isolates and their host resource and the inheritance and variation of the biological characters in asexual progenies, and to provide evidences for the integrated management of the fungus and the diseases caused by it. One hundred and seven isolates of the pathogenic fungus were obtained from the diseased tissues of cotton red rot, rice bakanae disease and maize ear rot collected from Anhui, Shandong, Hubei and Jiangsu, by isolation, identification and purification. Some biological characters （including colony morphology, growth rates and conidial production） of F. moniliforme isolates from cotton, rice and maize plants and their inheritance were investigated in vitro. The results showed that the changing trends of the my- eelium growth rates of the isolates from different hosts with the temperature, including the optimum values and the ranges of temperature for the myeelium growth, were basically consistent with each other. However, they were obviously different in colony morphology （especially in pigment production）, mycelial growth rates and conidial production. The average mycelium growth rate of the isolates from cotton was the largest, next the one from rice, the one from maize the least. There was a significant.difference at 0. 01 level in the mycelial growth rates among the isolates from the same population. The conidial production of the isolate from maize was the largest, next the one from rice, and the one from cotton the least. The variance analysis indicated that there was significant difference in the eonidial production among the isolate populations from different hosts, but no significant difference among the isolates from the same population. It was suggested that the conidial production of F. moniliforme isolates was mainly related to the host kinds, but little to the localities. The genetic tests showed that the colony morphology and the myeelial growth rates of F. moniliforme isolates from cotton, rice and maize plants could be inherited steadily in the single conidium progenies. However, there were two exhibitions in the inheritance of the conidial production. The eonidial production of F. moniliforme isolates Fml and Fm31, from cotton and rice respectively, could be inherited steadily in the single conidium progenies, while the character of isolate Fm19 from corn displayed variation in the first single eonidium generation.