Abstract: [Objective] Cotton Rhizoctoniosis and red rot disease are two main seedling diseases in Xinjiang cotton area.In order to obtain a strong pathogenic strain,this project aims to screen resistant varieties and disease control agents against the two diseases.[Method]In this project,30 Rhizoctonia solani and 30 Fusarium moniliforme isolated from cotton fields in south of Tianshan Mountains were used to conduct the comparative study on the pathogenicity of the susceptible cultivars(Jimian 11)after artificial inoculation.[Result]The comparison results showed that: There were significant differences in pathogenicity among the two pathogens strains;There were 8 strong pathogenic strains among the 30 Rhizoctonia solani strains,accounting for 26.7;of the total;There were 6 strong pathogenic strains among the 30 Fusarium moniliforme strains,accounting for 20;of the total;The pathogenicity of Rhizoctonia solani was significantly higher than that of Fusarium moniliforme among the two pathogenic strains;There were significant differences in pathogenicity with the strains derived from different areas in the two pathogens;In the four cotton areas of southern Xinjiang,a strain pathogenic force derived from Bazhou cotton area was relatively virulent,and virulence strain derived from Kezhou cotton areas was relatively weak;There were significant differences in pathogenicity among different strains of the same pathogen in the same area.[Conclusion]The pathogenicity of Rhizoctonia solani is significantly higher than Fusarium moniliforme in the cotton belt in the south of Tianshan Mountains and there are significant differences in pathogenicity among the two pathogens and various source strains derived from different areas.

摘要： [目的]研究棉花立枯病和红腐病是新疆棉区主要的两种苗期病害,获得强致力菌株,筛选针对两病的抗病品种及防病药剂.[方法]研究用分离自新疆天山以南各棉区的30个立枯丝核菌菌株和30个串珠镰刀菌分别对感病品种(冀棉11)进行人工接种后对上述菌株进行致病力比较.[结果]在两种病原菌间和种内的不同菌株间均存在显著的致病力差异;30个立枯丝核菌菌株中,强致病力菌株有8株,占总数的26.7;;30株串珠镰刀菌菌株中,强致病力菌株有6株,占总数的20;;两种病原菌之间立枯丝核菌的致病力极显著高于串珠镰刀菌;两种病原菌中,不同地区来源的菌株间存在显著的致病力差异,南疆四地中,来源于巴音郭楞蒙古自治州的菌株致病力相对较强,来源于克孜勒苏自治州的菌株致病力相对较弱,同一地区的同一病原的不同菌株间也存在显著的致病力差异.[结论]新疆天山以南棉区立枯丝核菌的致病力极显著地高于串珠镰刀菌;两种病原菌间及种内不同地区来源的菌株间均存在显著的致病力差异.