13 Jun Three major diseases of mustard crop and their management
सरसों की फसल के तीन प्रमुख रोग और उनका प्रबंधन 1. White rust disease of Mustard It is also called "White Blisters of Crucifers". In severe conditions, it caused yield losses up to 55% in late sown crops. Other crucifers host-Radish, Tumip, Cabbage, Cauliflower, Taramira, Spinach & sweet potato (non-crucifers). White creamy pustules & sporangia give white rusty appearance by exposing powdery mass of spores on the infected host surfaces, that's why it is called "white rust" (while it is not true rust. True rusts are caused by Uredinales i.e. Puccinia, Uromyces, Melampsora etc.). "Stag heads" are produced on floral parts due to systemic infection. Locally it is known as "Marodia Rog" or "Toontia Rog" Symptoms: Symptoms are produced on all parts except roots. Symptoms appear as a result of two types of infection: (i) In local infection: White creamy pustules of variable shape & size appear on the leaves, stem & inflorescence. Pustules merge to form large patches. The pustules, after the host epidermis ruptured, become powdery in appearance (Give white rusty appearance). (ii) In systemic infection: Young stems & floral organs are infected & stimulate hypertrophy (increase in size of cells) & hyperplasia (increase in number of cells) resulting in abnormal enlargement of infected organs which give stage head appearance. Upper surface Powdery white...