Author(s): Vinoda RH, Dr. Srikantaprasad D, Dr. Pushpa TN, Dr. Sumangala Koulagi, Dr. Mahathesha BN Naik and B Abdulrazaq

Abstract: The present investigation was carried out during rabi - 2021-22 at Kittur Rani Channamma College of Horticulture, Arabhavi, Belagavi district, Karnataka. cv. Kosi and Kranthi were subjected to gamma irradiation and ten advanced mutants along with two checks cv. Kosi and CIM Kranthi were selected from M₄ generation and evaluated for powdery mildew disease reaction under natural ecosystem in the months of November 2020 to February 2021. Among all the mutants highest percent disease incidence of powdery mildew was recorded by K₂₀P₄₁ and K₂₀P₂₃ at 70 Days after planting(DAP), 80 DAP and 90 DAP by showing small patches of white colored powdery masses on the upper surface of menthol mint leaves with chlorotic lesions on the opposite surface. When the disease progressed, these powdery patches grew in size and covered the entire abaxial surface of leaves causing defoliation and it happens in the mutant lines of Kranthi lineages. Significantly it reduces the crop production and cause serious economic losses upto10-20 percent (Kalra et al., 2005).

DOI: 10.33545/26174693.2024.v8.i5h.1140