Effect of Selected Essential Oils and Botanicals on Alternaria Blight (Alternaria brassicae (Berk) Sacc) of Mustard (Brassica juncea (Linn) Czern and Coss

Abstract

Indian mustard (Brassica juncea (L.) Czern.coss) is also known as sarson, rai or raya, toria or Lahi.it is a herbaceous annual plant. Mustard is the second important oilseed crop in the world after sunflower, soybean and palm oil. Alternaria blight disease caused by Alternaria brassicae (Berk.) Sacc. It has been reported from all the continents of the world. Average yield losses occur due to various pest and diseases among which Alternaria blight is an important disease. Field experiment was conducted at the research plot of the Department of Plant Pathology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, Uttar Pradesh during the rabi season of 2020-2021 to test, Effect of selected essential oils and botanicals against Alternaria blight (Alternaria brassicae (Berk.) Sacc) of mustard (Brassica juncea (Linn.) Czern and Coss), by foliar spray of certain essential oil, plant extracts and fungicide. The treatments were Neem oil @2%, Eucalyptus oil @2%, Pongamia oil @2%, Lawsonia inermis extract @15%, Chenopodium album extract @15% Mancozeb (treated check) @ 0.2% and control (untreated check). The percent disease intensity on leaves at 45, 60 and 75 DAS, number of siliquae per plant, number of seeds per siliquae, length of siliquae (cm), test weight of seed (1000 number), biological yield (gm) and seed yield were recorded. Among the treatments, maximum number of number of siliquaes (243.13), maximum number of seeds per siliquae (12.27), length of siliquae (5.16 cm), minimum disease intensity (%) (29.01 %), maximum test weight (3.57 gm), maximum yield (9.43 qt) and biological yield (24.70 gm) were recorded in the treatment T2 Eucalyptus oil @2% followed by T1 Neem oil @2%, T4 Lawsonia inermis  extract @15%, T3 Pongamia oil @2%, T5 Chenopodium extract @15%, when compared to treated check T6 Mancozeb @ 0.2% and untreated check T0. Higher gross return value (Rs. 66295), net return value (Rs. 29295), and B: C ratio (1.7:1) was found in the treatment T2 – Eucalyptus oil @2% as compared to T5–mancozeb and T0–control.