Purpose: Sticky traps are effective for monitoring and managing insect pests. In addition to pest... more Purpose: Sticky traps are effective for monitoring and managing insect pests. In addition to pest insects, beneficial insects are also caught in sticky traps. Hence, it is necessary to use traps to catch pest insects selectively. The attraction of different insect groups to coloured sticky traps was studied as an attempt to suppress the insect populations selectively in the field. Research Method: Sticky traps: yellow, blue, luminous green, white, and transparent (control) were set in the field for 24 hours, and the insects caught in traps were collected and identified by their ecological role: pests, beneficial and neutral insects as well as the taxonomic group in relation to the trap colour. Findings: Significant variation was found among the total numbers of insects attracted to different colour traps (χ2 =107 df=4 P<0.05). The highest number of insects was found in the luminous green trap (29.1%) followed by yellow (22.0%), white (18.8%), blue (17.9%), and transparent (12.2%)...
Agricultural Research for Sustainable Food Systems in Sri Lanka, 2020
Commercial crop cultivation in Sri Lanka became evident in the colonial times along with the shif... more Commercial crop cultivation in Sri Lanka became evident in the colonial times along with the shift of sustainable mixed cultivation systems to monoculture system. Insect pest problems also became evident with the change of cultivation system drawing the attention of growers. Studies focusing on pest management were first conducted with tea and coffee, followed by other plantation crops. Well planned, formal research studies commenced and results were published upon the establishment of Department of Agriculture in 1912 followed by other research stations for tea, rubber, and coconut. Biology and ecology of the insect pest species, pest behavior, and practices for population management were the interest of studies, and the recommendations were implemented and monitored. Most of the plant protection strategies that we practiced today were initiated at the early part of the twentieth century. Nonchemical pest management practices such as use of resistant varieties, shifting of planting dates, use of physical barriers against insect activities, management of alternate hosts, and classical biological control have been attempted to manage the target pest populations. Insecticide application was the interest by the mid of the last century, which has continued to date. The possible non-target effects and development of resistance in insect population were studied along with the chemical control of insect pests. Integrated pest management was the approach in many crops, along with modern extension strategies such as farmer field school. Of the insect pest management practices, certain strategies have not been fully utilized, and future research should be aimed for effective utilization of such pest management tools. Biological control, especially the conservation biocontrol and augmentative biocontrol, including microbial control, has a great potential to be used in the Sri Lankan context. Use of resistant varieties is a classic pest management approach but yet has a great potential to be used even in modern agriculture. Collaborative research to produce resistant varieties with good agronomic characters and high yield is a timely need and an essential tool to manage the insect pests. Novel insecticides with low mammalian toxicity are encouraged with improved safety procedures and modern application technologies. Overall, the new directions of entomological research should be under the considerations of sustainability, and environment friendliness.
No: 494 Plant Science and Forestry 577 EFFECTS OF PROFENOPHOS AND NEEM EXTRACTS ON TRICHOGRAMMA C... more No: 494 Plant Science and Forestry 577 EFFECTS OF PROFENOPHOS AND NEEM EXTRACTS ON TRICHOGRAMMA CHILONIS AND TRICHOGRAMMA ACHAE, EGG PARASITOIDS OF TRICHOPLUSIA NI A.S. Edirisinghe* and K.S. Hemachandra Department of Agricultural Biology, Faculty of Agriculture, University of Peradeniya, Sri Lanka *anushaaedirisinghe@gmail.com Use of Trichogramma chilonis and Trichogramma achae has been proposed to manage Trichoplusia ni and other caterpillar species in cabbage through augmentation and release. However, use of insecticide is inevitable due to frequent infestation of pest species. For the successful use of T. chilonis and T. achae, it is necessary to understand how these insects respond to the insecticides. Along with this objective, effects of neem extracts (81%) and profenophos (500g/l EC) on parasitoids were examined in the laboratory. The direct effect of insecticides on different growth stages of the parasitoids and the indirect effect or effects of insecticide residues on the p...
The soft scale insects belong to one of 15 families of phytophagous scale insects of economic imp... more The soft scale insects belong to one of 15 families of phytophagous scale insects of economic importance. A field survey of perennial plants in 16 agro-ecological zones of Sri Lanka was conducted in 2011–2012 to identify the soft scale species present and their host ranges. Fourteen species belonging to eight genera were identified. Two introduced species, Ceroplastes sinensis Del Guercio and Pulvinaria urbicola Cockerell, were recorded from Sri Lanka for the first time. The distribution and host range of the recorded species are documented and their potential threat as crop pests is discussed. Published literature on soft scales is reviewed.
Selected field vegetable crop combinations and increasing dosage of bio-char application, togethe... more Selected field vegetable crop combinations and increasing dosage of bio-char application, together with other alternative agronomic components of ecological agriculture (EA) were compared with conventional agriculture (CA) during the first three seasons of transition from CA to EA under hothumid tropical conditions and sandy regasolic soils in Kalpitiya, Sri Lanka. The recommendations of the Department of Agriculture (Sri Lanka) was followed for managing conventional agriculture plots while alternative ecological options were followed for plant nutrient and pest managements. Original Research Article Gunaratne et al.; ARJA, 14(1): 1-9, 2021; Article no.ARJA.65409 2 Capsicum-beet, Okra-beet and mae-spinach and radish-onion crop combinations could be selected for intercropping under ecological as well as conventional cropping systems based on their yield performances (Land Equivalent Ratio -LER) or other yield components. Even though plant growth rates and crop yields were lower at th...
Two species of predatory hoverflies (Diptera: Syrphidae) belong to genus Syrphus Fabricius (1775)... more Two species of predatory hoverflies (Diptera: Syrphidae) belong to genus Syrphus Fabricius (1775) were identified by a survey in vegetable growing areas of mid country region of Sri Lanka. The Syrphus species 1 was collected from aphid colonies on brinjal (Solanum melongena), cabbage (Brassica oleracea var. capitata), long bean (Vigna sesquipedalis), pea (Pisum sativum) and wing bean (Psophocarpus tetragonolobus). The Syrphus species 2 was collected from aphid colonies on cabbage (Brassica oleracea var. capitata) and cauliflower (Brassica oleracea var. botrytis. One predatory brown lacewing (Neuroptera: Hemerobiidae) species belong to genus Micromus Rambur (1842) from aphid colonies on cabbage (Brassica oleracea var. capitata), and another carnivorous lepidopteran species (Lycaenidae) Spalgis epius (Westwood, 1852) from Pseudococcus colonies on Solanum xanthocarpum were also identified by the survey. INTRODUCTION Coccinellids are found to be the most abundant predatory insects in ve...
Purpose: Sticky traps are effective for monitoring and managing insect pests. In addition to pest... more Purpose: Sticky traps are effective for monitoring and managing insect pests. In addition to pest insects, beneficial insects are also caught in sticky traps. Hence, it is necessary to use traps to catch pest insects selectively. The attraction of different insect groups to coloured sticky traps was studied as an attempt to suppress the insect populations selectively in the field. Research Method: Sticky traps: yellow, blue, luminous green, white, and transparent (control) were set in the field for 24 hours, and the insects caught in traps were collected and identified by their ecological role: pests, beneficial and neutral insects as well as the taxonomic group in relation to the trap colour. Findings: Significant variation was found among the total numbers of insects attracted to different colour traps (χ2 =107 df=4 P<0.05). The highest number of insects was found in the luminous green trap (29.1%) followed by yellow (22.0%), white (18.8%), blue (17.9%), and transparent (12.2%)...
Agricultural Research for Sustainable Food Systems in Sri Lanka, 2020
Commercial crop cultivation in Sri Lanka became evident in the colonial times along with the shif... more Commercial crop cultivation in Sri Lanka became evident in the colonial times along with the shift of sustainable mixed cultivation systems to monoculture system. Insect pest problems also became evident with the change of cultivation system drawing the attention of growers. Studies focusing on pest management were first conducted with tea and coffee, followed by other plantation crops. Well planned, formal research studies commenced and results were published upon the establishment of Department of Agriculture in 1912 followed by other research stations for tea, rubber, and coconut. Biology and ecology of the insect pest species, pest behavior, and practices for population management were the interest of studies, and the recommendations were implemented and monitored. Most of the plant protection strategies that we practiced today were initiated at the early part of the twentieth century. Nonchemical pest management practices such as use of resistant varieties, shifting of planting dates, use of physical barriers against insect activities, management of alternate hosts, and classical biological control have been attempted to manage the target pest populations. Insecticide application was the interest by the mid of the last century, which has continued to date. The possible non-target effects and development of resistance in insect population were studied along with the chemical control of insect pests. Integrated pest management was the approach in many crops, along with modern extension strategies such as farmer field school. Of the insect pest management practices, certain strategies have not been fully utilized, and future research should be aimed for effective utilization of such pest management tools. Biological control, especially the conservation biocontrol and augmentative biocontrol, including microbial control, has a great potential to be used in the Sri Lankan context. Use of resistant varieties is a classic pest management approach but yet has a great potential to be used even in modern agriculture. Collaborative research to produce resistant varieties with good agronomic characters and high yield is a timely need and an essential tool to manage the insect pests. Novel insecticides with low mammalian toxicity are encouraged with improved safety procedures and modern application technologies. Overall, the new directions of entomological research should be under the considerations of sustainability, and environment friendliness.
No: 494 Plant Science and Forestry 577 EFFECTS OF PROFENOPHOS AND NEEM EXTRACTS ON TRICHOGRAMMA C... more No: 494 Plant Science and Forestry 577 EFFECTS OF PROFENOPHOS AND NEEM EXTRACTS ON TRICHOGRAMMA CHILONIS AND TRICHOGRAMMA ACHAE, EGG PARASITOIDS OF TRICHOPLUSIA NI A.S. Edirisinghe* and K.S. Hemachandra Department of Agricultural Biology, Faculty of Agriculture, University of Peradeniya, Sri Lanka *anushaaedirisinghe@gmail.com Use of Trichogramma chilonis and Trichogramma achae has been proposed to manage Trichoplusia ni and other caterpillar species in cabbage through augmentation and release. However, use of insecticide is inevitable due to frequent infestation of pest species. For the successful use of T. chilonis and T. achae, it is necessary to understand how these insects respond to the insecticides. Along with this objective, effects of neem extracts (81%) and profenophos (500g/l EC) on parasitoids were examined in the laboratory. The direct effect of insecticides on different growth stages of the parasitoids and the indirect effect or effects of insecticide residues on the p...
The soft scale insects belong to one of 15 families of phytophagous scale insects of economic imp... more The soft scale insects belong to one of 15 families of phytophagous scale insects of economic importance. A field survey of perennial plants in 16 agro-ecological zones of Sri Lanka was conducted in 2011–2012 to identify the soft scale species present and their host ranges. Fourteen species belonging to eight genera were identified. Two introduced species, Ceroplastes sinensis Del Guercio and Pulvinaria urbicola Cockerell, were recorded from Sri Lanka for the first time. The distribution and host range of the recorded species are documented and their potential threat as crop pests is discussed. Published literature on soft scales is reviewed.
Selected field vegetable crop combinations and increasing dosage of bio-char application, togethe... more Selected field vegetable crop combinations and increasing dosage of bio-char application, together with other alternative agronomic components of ecological agriculture (EA) were compared with conventional agriculture (CA) during the first three seasons of transition from CA to EA under hothumid tropical conditions and sandy regasolic soils in Kalpitiya, Sri Lanka. The recommendations of the Department of Agriculture (Sri Lanka) was followed for managing conventional agriculture plots while alternative ecological options were followed for plant nutrient and pest managements. Original Research Article Gunaratne et al.; ARJA, 14(1): 1-9, 2021; Article no.ARJA.65409 2 Capsicum-beet, Okra-beet and mae-spinach and radish-onion crop combinations could be selected for intercropping under ecological as well as conventional cropping systems based on their yield performances (Land Equivalent Ratio -LER) or other yield components. Even though plant growth rates and crop yields were lower at th...
Two species of predatory hoverflies (Diptera: Syrphidae) belong to genus Syrphus Fabricius (1775)... more Two species of predatory hoverflies (Diptera: Syrphidae) belong to genus Syrphus Fabricius (1775) were identified by a survey in vegetable growing areas of mid country region of Sri Lanka. The Syrphus species 1 was collected from aphid colonies on brinjal (Solanum melongena), cabbage (Brassica oleracea var. capitata), long bean (Vigna sesquipedalis), pea (Pisum sativum) and wing bean (Psophocarpus tetragonolobus). The Syrphus species 2 was collected from aphid colonies on cabbage (Brassica oleracea var. capitata) and cauliflower (Brassica oleracea var. botrytis. One predatory brown lacewing (Neuroptera: Hemerobiidae) species belong to genus Micromus Rambur (1842) from aphid colonies on cabbage (Brassica oleracea var. capitata), and another carnivorous lepidopteran species (Lycaenidae) Spalgis epius (Westwood, 1852) from Pseudococcus colonies on Solanum xanthocarpum were also identified by the survey. INTRODUCTION Coccinellids are found to be the most abundant predatory insects in ve...
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