Losses Caused Due to Alternaria Blight Disease in the Grain Yield of Pigeonpea

A field trial was conducted during 2010–11 and 2011–12 to ascertain the losses caused byalternaria blight disease in the grain yield ofpigeonpea.Asusceptible variety ‘Bahar’ was sown in the research field. The artificial inoculations of mass culture ofAlternaria tenuissima (Kunze ex pers.) Wiltshire was done in the inoculated plots at 60 DAS to create the desirable level of disease pressure of alternaria blight. The uninoculated plots (control) were sprayed with Mancozeb 75 WP (0.25%) to check the alternaria blight disease. It revealed that inoculated plots showed maximum disease intensity (44.19%) was recorded in plots which did not receive any spray of Mancozeb. In plots with one, two three and four sprays of Mancozeb, disease intensity was recorded as 31.01, 20.57, 13.75 and 11.88% and the mean % disease control was 29.88, 53.45, 68.88 and 73.09% respectively. Almost similar trend of disease intensity, crop yield and number of 100 grain seed weight was recorded in different treatments with Mancozeb.