Severity and distribution of purple blotch in major garlic growing areas of northern Karnataka

K. N.  VIJAYKUMAR; SHRIPAD  KULKARNI; P.V.  PATIL; T. R.  SHASHIDHAR; D. N.  KAMBREKAR

K. N. VIJAYKUMAR Department of Plant Pathology,University of Agricultural Sciences, Dharwad - 580 005, Karnataka, India
SHRIPAD KULKARNI Directorate of Extension,University of Agricultural Sciences, Dharwad - 580 005, Karnataka, India
P.V. PATIL Department of Plant Pathology,University of Agricultural Sciences, Dharwad - 580 005, Karnataka, India
T. R. SHASHIDHAR Department of Horticulture,University of Agricultural Sciences, Dharwad - 580 005, Karnataka, India
D. N. KAMBREKAR Department of Agricultural Entomology,University of Agricultural Sciences, Dharwad - 580 005, Karnataka, India

Keywords: Alternaria porri, Per cent disease index, Survey, Thrips

Abstract

Purple blotch caused by Alternaria porri is the most destructive disease causing yield loss up to 20 to 60 percent. Survey was conducted during the two consecutive years 2019-20 and 2020-21 in the major garlic growing districts ofnorthern Karnataka to know the severity of disease.The highest mean per cent disease severity was observed in Dharwaddistrict (22.78 and 24.81 PDI during Kharif 2019 and 2020; 27.80 and 26.46 PDI during Rabi 2019 and 2020 respectively).On contrary, minimum mean per cent disease severity was noticed in Gadag district (14.95 and 17.43 PDI during Kharif2019 and 2020; 17.40 and 20.18 PDI during Rabi 2019 and 2020 respectively).However, the higher severity of disease wasnoticed in Rabi (24.80 and 24.28 PDI) compared to Kharif season(19.34 and 20.64 PDI) during 2019 and 2020, respectively.Irrespective of the seasons and years, disease severity was more severe in the fields of black soil and irrigated conditionwhen compared to red soil and rainfed condition.