Population dynamics and management of major insect-pests on cabbage

Loading...
Thumbnail Image
Date
2019
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
The present studies on population dynamics and management of insect-pests on cabbage were conducted at Experimental Area, Department of Entomology, CCS Haryana agricultural University, Hisar during 2017-18 and 2018-19. The population dynamics studies of major insect-pests revealed that the peak population of diamondback moth (Plutella xylostella), semilooper (Trichoplusia ni) and aphid (Brevicoryne brassicae) was observed in 11th and 12th SMW (Standard Meteorological Weeks) last week of March, 2017-18 and 2018-19 whereas, the peak population of cabbage butterfly (Pieris brassicae) was observed in 13th SMW i.e., first week of April in both the years. The correlation studies revealed that the population of diamondback moth, semilooper and aphid had a positive and significant correlation with maximum and minimum temperature and negative but significant correlation with morning and evening relative humidity during 2017-18. In 2018-19 the population of diamondback moth and aphid had a positive and significant correlation with maximum temperature and sunshine hours and negative but significant correlation with evening RH in both the years. Population of semilooper showed the positive and significant correlation with temperature (both maximum and minimum) and sunshine hours and negative but significant correlation with relative humidity (both morning and evening) in both the years. Coccinellids, syrphid fly and spiders were recorded as natural enemies along with the population of insect-pests. Peak incidence of natural enemies was recorded in 12th and 13th SMW i.e., last week of March and 1st week of April. The efficacy studies of insecticides showed that the lowest population of diamondback moth, semilooper and cabbage butterfly was observed in chlorantraniliprole 18.5 SC @ 50 ml and the highest population of these pests was observed in nimbecidine 0.03 EC during both the years. While in the case of aphids malathion 50 EC proved to be the best insecticide and Bacillus thuringiensis was proved to be the least effective insecticides in reducing the population of pest in both the years. The cumulative effect of all the treatments indicated that the maximum yield was recorded in chlorantraniliprole 18.5 SC @ 50 ml i.e., 194.70 q/ha (pooled) and the lowest in nimbecidine 0.03 EC i.e., 157.70 q/ha (pooled). The IPM modules studies revealed that module M2 was proved to be the effective module against diamonback moth, semilooper and cabbage butterfly during both the years with 3.41, 1.01 and 17.18 larvae/plant, respectively followed by module M3 which recorded 3.51, 1.13 and 18.74, respectively. Module M1 proved to be the least effective module (4.10, 1.24 and 19.14 larvae/plant, respectively) but superior over control. In case of aphid, module M3 was the most effective module followed by module M1 (11.59 aphids/plant). Module M2 (11.91 aphids/plant) proved to be the least effective module but effective over control. The cumulative effect of two years data revealed that the maximum yield was recorded in module M2 (198.90 q/ha) statistically at par with module M3 (191.64 q/ha) and the lowest yield was recorded in module M1 (183.14 q/ha). The residues of chlorantraniliprole 18.5 SC (50 ml and 100 ml/ha) and malathion 50 EC (1 L and 2 L/ha) were determined at different intervals i.e., 0 (1 hr), 3, 5, 7, 10 and 15 days after application of insecticides. Chlorantraniliprole 18.5 SC was dissipated faster than malathion 50 EC. The residue level of malathion was found below MRL (Maximum Residue Limit) i.e., 3.0 mg kg-1on 0 day at single and double dose whereas, the residue level of chlorantraniliprole was found below MRL i.e., 0.03 mg kg-1 after 7th day at single dose and after 10th day at double dose.
Description
Keywords
null
Citation
Collections