Pathogenicity Differentiation of Fusarium moniliforme Isolates to Cotton Seedlings and the Inheritance in Single Conidium Progenies

The pathogenicity of the isolates of Fusarium moniliforme from different hosts to the cotton seedlings was investigated by applying mycelial block wound inoculation,respectively.The results showed that all of the tested isolates caused red rot lesions on the leaves of cotton,but there was significant difference in the average diameters of the lesions caused by different isolates,suggesting that there was significant differentiation in pathogenicity of F.moniliforme to the leaves of cotton seedlings among isolates.Generally,the isolates from cotton were strongly pathogenic to the leaves of cotton,but the isolates from maize and rice were weakly pathogenic.However,there was difference in pathogenicity among the different isolates from the same host,and the pathogenicity difference was not obviously related to the localities of isolates.The genetic tests showed that the pathogenicity of F.moniliforme isolates from cotton,rice and maize plants to cotton seedling leaves could be inherited steadily in the single conidium progenies for two generations.