Seasonal Incidence of Head Borer, Hellula undalis Fabricius and Coccinellid Predators in Cabbage and Their Correlation with Weather Parameters

The investigation was conducted to study the seasonal incidence of cabbage head borer, Hellula undalis Fabricius at Regional Horticultural Research Station Farm, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India during 2021-22. The incidence of H. undalis on cabbage commenced from 48th Standard Meteorological Week (SMW) with its peak in the second SMW and then decreased gradually until 10th SMW, i.e., end of the crop growth period. The H. undalis larval population had highly significant negative correlation with maximum and minimum temperature and evaporation. There was 88.78 per cent association of the H. undalis population with significant weather parameters. Only coccinellid predators viz., Coccinella transversalis Fabricius and Cheilomenes sexmaculata Fabricius, were noticed in cabbage ecosystem during the crop growth period and none of the parasitoids were reported. The initial occurrence of coccinellids was noted during 48th SMW and the population increased gradually in successive weekly counts and reached the peak during second SMW and thereafter, population declined gradually until 10th SMW. The maximum and minimum temperature had significant negative correlation with the population of coccinellid beetles. The variation in abundance of coccinellids was contributed by significant abiotic factors by 85.30 per cent.