INVESTIGATION ON USE PATTERN, EFFICACY AND PERSISTENCE OF INSECTICIDES IN/ON CAPSICUM GROWN IN POLYHOUSE
Loading...
Date
2018
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Mahatma Phule Krishi Vidyapeeth, Rahuri.
Abstract
Investigation on use pattern, efficacy and persistence of certain insecticides in capsicum grown in polyhouse, were undertaken at Mahatma Phule Krishi Vidyapeeth, Rahuri (M.S.) during 2016-17 and 2017-18. The usage pattern of insecticides in capsicum was studied by undertaking a survey at Western Maharashtra (Ahmednagar, Pune and Nasik). Capsicum growing farmers (65 farmers from each district: polyhouse – 40, shadenet – 15 and open field - 10) were randomly surveyed using a structured questionnaire. Results showed that, either in polyhouse or in shadenet/ open field, farmers mainly relied on conventional insecticides (65.11 & 72.38%) followed by novel insecticides (21.98 & 24.50%) and biopesticides (12.92 & 3.11%) for the pest management. Farmers from Ahmednagar used higher quantity of insecticides as compared to Nasik and Pune farmers. In addition, insecticides were used at higher quantity in polyhouses as compared to open field. The commonly used insecticides based on their use intensity were chlorpyrifos, profenophos (organophosphates), lambda cyhalothrin and deltamethrin (pyrethroids). Further, farmers from Nasik (mainly polyhouse capsicum growers) were aware of proper handling of the pesticides as compared to other two districts.
Majority of the farmers (>50%) from the surveyed region were able to identify different pests. Based on their response, the commonly occurring pests were sucking pests like mites, thrips, aphids, etc. Among them mites (20-39%), thrips (26-32%) and aphids (12.79-23.08%) were severe. Farmers were also aware of natural enemies and bioagents, whereas, very few farmers (<15%) were aware of recommended insecticides in capsicum either in polyhouse or open field. Though, majority of the farmers (>40%) knew about toxic effects of pesticide residues, still few farmers (<25%) were aware of safe waiting period.
Studies on bioefficacy of newer molecules against major sucking pests, were conducted on farmer’s field at Kangoni, Newasa (Tq), Ahmednagar (Dist) of Maharashtra. The results revealed that imidacloprid 17.8SL was the effective insecticide against aphids with 63.75% reduction in population and registered highest yield (34.43 t/ha) and C:B ratio. As against thrips, cyantraniliprole 10.26 OD found most promising by higher population reduction (81.55% reduction) with highest yield (43.60 t/ha). It was followed by fipronil 80 WG (77.88% reduction). Fenpyroximate 5EC (83.98% reduction) proved highly effective against mites followed by hexythiazox 5.45EC and spiromesifen 22.9SC. The yield and cost economics data showed that fenpyroximate registered highest yield (38.43 t/ha) and proved cost effective with higher C:B ratio. Among the biopesticides, nimbecidine proved effective against all these sucking pests, followed by L. lecanii.
Insecticides like chlorpyriphos, ethion, triazophos, quinalphos, profenophos, deltamethrin, imidacloprid and spiromesifen were studied for their dissipation kinetics, at recommended and double the recommended dose. The laboratory studies on dissipation of insecticide residues were carried out at AINP on Pesticide Residues Laboratory, Department of Agricultural Entomology, M.P.K.V., Rahuri. Results revealed that, insecticide residues persisted upto 5 to 7 days in open field, whereas it took 15 to 25 days in polyhouse to reach to below quantification limit. In polyhouse, chlorpyriphos residues persisted up to 15 to 20 days with a half life of 3.43 to 5.09 days, as against in open field the residues persisted upto 3 to 5 days with half life of 1.39 to 2.09 days. As regards ethion, the residues in polyhouse capsicum persisted upto 10 to 15 days with half life of 2.39 to 3.07 days. Whereas, in open field the residues persisted upto 3 to 5 days with a half-life of 1.61 to 1.78 days.
Initial residues of triazophos persisted upto 15 to 20 days in polyhouse with half life of 2.96 to 3.92 days, whereas in open field, residues persisted upto 5 to 7 days with a half life of 1.49 to 2.07 days. As regards quinalphos, the residues persisted upto 15 to 20 days with half life of 3.26 to 3.95 days in polyhouse as against in open field, the residues persisted upto 5 to 7 days with a half life of 1.27 to 1.86 days. In polyhouse capsicum, profenophos residues persisted upto 10 to 15 days with a half life of 2.45 and 3.49 days. Whereas, in open field, residues persisted upto 5 to 7 days with half life of 1.52 and 1.72 days. Deltamethrin residues persisted upto 7 to 10 days with half life of 2.05 and 2.45 days in polyhouse, whereas, in open field, residues persisted upto 3 to 5 days with a half life of 1.51 to 1.86 days. Initial residues of imidacloprid persisted upto 7 to 10 days, with a half life of 1.88 to 2.61 days in polyhouse grown capsicum. Whereas, its metabolite 6-chloronicotinic acid was not detected. As regards spiromesifen, the initial residues persisted upto 7 to 10 days, with a half life of 1.72 to 2.64 days. All the studied insecticides followed dissipation pattern of first order kinetics and the residues were not detected in the soil samples collected at harvest.
It may be inferred that there is need to create awareness among the capsicum growers regarding good agricultural practices (GAP). To mitigate the identified problems, Regulatory authorities, farmers and Agrochemical Dealers must form a common platform and create awareness about proper and safe handling of pesticides to produce residue free capsicum from the point of consumer safety.
Description
Keywords
null