INDUCTION OF SYSTEMIC RESISTANCE BY BIOTIC AND ABIOTIC COMPOUNDS AGAINST ALTERNARIA BLIGHT OF CAULIFLOWER CAUSED BY ALTERNARIA BRASSICAE

Abstract

Alternaria blight of cauliflower is initiated by Alternaria brassicae, is considered as one of the significant diseases caused in cauliflower crop cultivated in all the growing areas of the world. Alternaria blight disease severity in cauliflower occurs after initiation of curd formation and continues till seed pods are set. Several opportunities include improvement of resistant cultivars; crop rotation, biological control, chemical pesticides, and tillage are used to control this particular disease. By using chemical pesticide mostly diseases can be controlled. In present investigation the three abiotic (salicylic acid, oxalic acid, benzothiadiazole and two biotic compound Trichoderma harzianum, and T.viride lab formulations were used to control this disease. Treatments were evaluated for their ability to reduce illness and prevent the production of conidia, a hallmark of pathogen proliferation. However, the disease control was maximum in variety Doctor II and under post inoculation technique. The maximum disease control was observed with the treatment of bion (93.86%) followed by salicylic Aacid (90.93%) and oxalic acid (89.06%) @ 50 mg.L concentration. The biotic compound T. harziaznum (4g/Kg seeds) also showed effective disease control (87.2%) followed by T.viride (84.53%). Although, the disease initiation in variety SV40551AC was two days later and the infection index was lower in Doctor II due to its tolerance nature. Keywords: Alternaria brassicae, cauliflower, Alternaria blight, entry routes, pathogen.