Management of Alternaria porri (Ellis) causing purple blotch of onion

The Present Investigation was carried out at Central Research Field of the Department of Plant Pathology SHUATS Prayagraj (U.P.) during Rabi 2019-20 cropping season to ascertain the Eco-friendly management of Alternaria porri (Ellis) causing purple blotch of onion (Allium cepa L.). Efficacy of different essential oils & bio-agents was evaluated on different growth and yield parameters of onion crop. Maximum plant height @ 30 DAT (13.20 cm) 60 DAT (37.27 cm) 90 DAT (59.28 CM) number of leaves @ 30 DAT (3.90)60 DAT (7.70) 90 DAT (10.73) neck thickness at maturity (1.49 cm) yield per ha (323.97Q) diameter of bulb (5.84 cm) weight of bulb (73.63 g) was recorded combination of Trichoderma viride + Neem oil (T5). The highest incidence of purple blotch was recorded in Control (61.37 per cent) followed by Castor oil (52.09 percent) Clove oil (49.44%) at bulb development stage of crop. Trichoderma viride (2.5%) + Neem oil (2.5%) Trichoderma viride (10%) and Neem oil (5%) was found most effective essential oils and bio-agents against Alternaria porri. NHRDFRed-3 was found more suitable variety amongst all two varieties regarding yield / disease / net return point of view.