Assessment on the Incidence of Fusarium Wilt of Marigold Caused by Fusarium oxysporum f. sp. Callistephi (FOC) in Major Marigold Growing Areas of Dindugul District, India

Abstract

Marigold (Tagetes erecta L.), one of the commercially exploited ornamental flower crops belonging to the family Asteraceae is naturalized in tropical and subtropical regions worldwide.It is affected by several fungal, bacterial and viral diseases. Among these Fusarium wilt caused by the fungus Fusarium oxysporum f.sp. callistephi causes 30-40% yield loss. A survey was conducted to investigate the incidence and severity of Fusarium wilt incited by Fusarium oxysporum f.sp.  callistephi in ten  major marigold growing areas of Dindugul district. The occurrence of wilt disease incidence ranged from 20 % to 49% was noticed. Plant showing typical symptoms were taken from 10 fields and identified based on symptom appearance as well as morphological characteristics. The result of the survey revealed that wide range of infection and severity of wilt disease were occurred in the major marigold growing areas in Dindugul district. Foc3 recorded the maximum wilt incidence followed by Foc7 and the minimum wilt incidence was recorded by Foc8. The pathogenicity of the fungal pathogen was also proved after artificial inoculation of the marigold seedlings.