Relation between insect damage and yield of Indian mustard (Brassica juncea) sown on different dates in Gujarat

A field experiment was conducted during winter season (rabi) 1988-89 to 1992-93 to study the effect of different dates of sowing indian mustard [Brassica juncea (L.) Czernj. & Cosson] on incidence of pests and crop yield. The crop sown in the third week of September and first week of October had significantly lower population of mustard sawfly [Athalia lugens proxima (Klug.)] and aphid [Lipaphis erysimi (Kalt.)], which reflected on the yield and gave higher yield than the crop sown in the third week of November.