A field experiment was conducted at Student Instructional Farm, . Azad University of Agriculture and Technology, Kanpur with three dates of sowing viz. November, 03, 10 and November, 17, 2011 and used three varieties of mustard viz. Vaibhav, Vardan and Varuna with four replication under Split Plot Design. | Influence of weather on the incidence and spread of aphid in Mustard Brassica juncea L.