Population dynamics of major insect pest on mustard Brassica juncea in Vidarbha region and its correlation with weather parameters

The present study on seasonal incidence of mustard aphid Lipaphis erysimi (Kalt) with their natural enemies, was taken at the field of AICRP on Rapseed and Mustard, College of Agriculture Nagpur, during Rabi 2023-24. The experiment was laid out in 10m2 separate plot. Based on regular monitoring it was observed that only three insect pests, mustard aphid (Lipaphis erysimi), mustard sawfly (Athalia lugens proxima) and leaf webber (Crocidolomia binotalis) were found to cause damage in mustard crops in this area. The population of natural enemies Coccinellids and Aphid parasitoid (Diaretiella rapae) were also documented as major natural enemies of mustard aphid. The incidence of mustard aphid was recorded from 50th Standard Meteorological Week (SMW) 2023, which continued up to 9th Standard Meteorological Week (SMW) of 2024. Mustard sawfly was reaches peak population in 49th SMW. Mustard sawfly population reached its peak in 1st SMW. Thereafter, the population was declined and it was not appeared in 4th SMW (last week of January). The appearance of leaf webber population was initiated from 49th SMW to 5th SMW. The population of Natural enemies viz., coccinellid (Coccinella septempunctata) (3.60 number/plant) and mustard aphid parasitoid (Diaeretiella rapae) (50.35%) also seen from 52nd SMW to 9th SMW.