Debraj Adhikari | Tribhuvan University (IAAS) (original) (raw)

Papers by Debraj Adhikari

Acta agraria Debreceniensis, Jun 3, 2024

Journal of Agriculture and Environment

Problems of Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) in citrus orchards have been i... more Problems of Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) in citrus orchards have been increasing in Nepal. The reason behind the failure in CCF control is the lack of a clear and thorough understanding of the adult emergence period in different altitudes. Therefore, the pupae of CCF were collected from the soil below the infested sweet orange trees in Sunapati Rural Municipality, Ramechhap, Nepal and reared in containers of height 5 cm and diameter 6 cm (10 pupae per container) in randomized complete block design selecting different locations as treatments, viz. 1247 masl (Bethan), 1354 masl (Nagsiwa), 1443 masl (Aarukharka), 1561 masl (Sadi), 1650 masl (Dimipokhari) replicating four times. Early peak emergences of adult CCF (four weeks earlier in 4th week of April) occurred at lower altitudes as compared to the higher altitudes (in 4th week of May), where peak-emergence was recorded. Male: female ratio (range 1.05-1.37) did not differ significantly at different altitudes,...

Journal of the Institute of Agriculture and Animal Science

Chinese citrus fly is the major pest of sweet orange in citrus growing districts of Bagmati Provi... more Chinese citrus fly is the major pest of sweet orange in citrus growing districts of Bagmati Province Nepal. Farmer’s production constrains and production problems such as Chinese citrus fly problem in sweet orange are not well documented and studied. This study was conducted in Sindhuli, Ramechhap, Dolakha and Kavre districts of Bagmati Province in 2021 with aim to understand the farmer’s perception, knowledge about CCF and their management practices using semi-structured questionnaire. Collected survey data was analyzed using the SPSS-20 and MS Excel. The survey results depicted that the intensity of Chinese citrus fly damage has been decreased in Sindhuli district with the infestation level of < 20% in sweet orange orchard. However, CCF population as well as their damage level was in increasing trend of > 50% in sweet orange orchard in Ramechhap, and > 80% in Dolakha and Kavre district. Chinese citrus fly loss has been recorded up to 25% in Mandarin orange in Dolakha and ...

Journal of the Plant Protection Society

Fruit flies (Diptera: Tephritidae) are devastating pests in citrus orchards of Nepal causing huge... more Fruit flies (Diptera: Tephritidae) are devastating pests in citrus orchards of Nepal causing huge losses of fruits. A farmer's survey was carried from March to December, 2021 randomly selecting 40 citrus orchard owners, and at the same time, a field monitoring of fruit flies organised in randomized complete block design with 7 times replicated 3 treatments (Cue lure and malathion in Steiner trap, Methyl eugenol and malathion in Steiner trap and protein bait in McPhail trap) were conducted in Ramechhap district of Nepal. Survey revealed that Chinese citrus fly was the most problematic insect pest of citrus orchard. However, only few farmers were practising effective control measures against this pest. Nine species of fruit flies were trapped in different lures and protein bait, when the number of fruit flies differed significantly (p<0.05) except Bactrocera correcta and Zeugodacus cucurbitae, which were found attracted in negligible number in Methyl eugenol and Cue lure, respe...

Journal of the Plant Protection Society

Chinese citrus fly, Bactrocera minax (Enderlein) is a major pest of citrus fruits that causes sig... more Chinese citrus fly, Bactrocera minax (Enderlein) is a major pest of citrus fruits that causes significant fruit losses in citrus orchards in Nepal, China, Bhutan and India. In 2021, a field study was conducted to know the oviposition period of this pest in a sweet orange orchard in Sindhuli, Nepal. The pest deposits its eggs on 25-50 mm citrus fruits during June-July. The timing of egg laying is crucial in designing and deploy adult fly management such as protein bait in citrus orchards.

Fundamental and Applied Agriculture

The study was conducted to access the species diversity of fruit fly and their population dynamic... more The study was conducted to access the species diversity of fruit fly and their population dynamics, awareness among mandarin growers on the nature of damage, and factors affecting the awareness in the Jajarkot district of Nepal in 2021. The study consists of two parts: farmer’s survey and monitoring of fruit flies. The farmer’s survey was carried out in randomly selected sixty households whose orchards were at least five years old in command areas of citrus zone, Jajarkot. Fruit fly monitoring was done in three mandarin orchards of Kushe Rural Municipality and Bheri Municipality using cue-lure, methyl eugenol, and great fruit fly bait. The survey revealed that only thirty percent of the farmers were aware of the nature of fruit fly damage. Experience in mandarin cultivation was found to be significantly affecting the awareness of mandarin growers on fruit fly damage. The mandarin growers were practicing pruning, collection and destruction of fallen fruits, use of chemicals, and trap...

Journal of the Plant Protection Society

The study was carried out from April-August, 2017 to monitor the population of Tuta absoluta and ... more The study was carried out from April-August, 2017 to monitor the population of Tuta absoluta and to assess the management practices being adopted in Kavre, Nepal. Study consisted of two major parts: monitoring of insect population and farmer’s survey. The population of T. absoluta ranged from 51 to 972 in each Wota -T trap. The highest population of the insect in traps were recorded in Dhulikhel followed by Panauti and Banepa. Majority of tomato growers (78%) reported T. absoluta as the most problematic among other pests, diseases and disorders. The data from E-Plant clinic at Panchkhal revealed the degree of severity of T. absoluta in tomato crop. Tomato growers have adopted cultural, physical, mechanical, para-pheromone lures, quarantine, botanical and chemical methods for the management of this pest. Majority of them relied on chemical pesticide (94%) followed by cultural practices (86%) and Tomato Leaf Miner (TLM) lure (66%) based on cumulative percentage of respondents. Use of ...

Journal of the Plant Protection Society

Agricultural production has been challenged by various biotic and abiotic factors in Nepal. Losse... more Agricultural production has been challenged by various biotic and abiotic factors in Nepal. Losses incurred by different insect pests and diseases are remarkable. As a counter measure, Government of Nepal has implemented various activities through extension, research and academic institutions. Integrated Pest Management (IPM) has been the central approach of plant protection in Nepal. It was initiated in 1997 with an aim to reduce the excessive and injudicious use of chemical pesticides to enhance the crop production, paying due attention on gender mainstreaming, and social inclusion. Besides, plant clinic program is gaining popularity in Nepal to provide plant health extension advisory services. Being a signatory country of Rotterdam Convention and Stockholm Convention, Nepal has imposed ban on sixteen different types of chemical pesticides including persistent organic pollutants (POPs). Botanicals and bio-pesticides are also used in agriculture to manage pests and diseases of crop...

Journal of Agriculture and Environment, 2019

Nepal Journal of Science and Technology, 2015

A field investigation was carried out during July 2008 to April 2009 in a farmer’s field at Gunja... more A field investigation was carried out during July 2008 to April 2009 in a farmer’s field at Gunjanagar-5, Chitwan, Nepal to evaluate the influence of time and intensity of pruning on growth and flowering behaviour of cut rose cv. Super Tata (Rosa hybrida). The experiment was laid out in a completely randomized block design with nine treatment combinations and replicated thrice. The treatments comprised of three dates of pruning i.e. 30th July, 15th August and 30th August and three pruning intensities i.e. heavy (6 buds per plant), medium (12 buds per plant) and light (18 buds per plant). Both time and intensity of pruning significantly affected growth and yield attributing parameters. The plants pruned heavily on 30th July produced highest plant height, number, length and diameter of canes. Similarly, stem bud as well as floral initiation were also earlier as compared to other treatments. On the other hand, fresh and dry weight of leaf and leaf area index were highest from the plant...

International Journal of Environment

Chinese citrus fly, Bactrocera minax is a destructive and univoltine pest of citrus fruits. Geogr... more Chinese citrus fly, Bactrocera minax is a destructive and univoltine pest of citrus fruits. Geographical altitudinal gradients as well as prevailing climate affect the biology and ecology of insect. Hence, this study aimed to ascertain the effect of altitude on the adult emergence and morphological variations in various ecological settings of Ramechhap district of Nepal from February to June 2021 in citrus orchard. Six altitude ranges were selected in 50 m distance from 1200 to 1500 m above sea level (masl), ranging from 1201-1250 masl, 1251-1300 masl, 1301-1350 masl, 1351-1400 masl, 1401-1450 masl and 1451-1500 masl. The peak adult emergence periods were the 2nd, 3rd, 4th week of April in 1201-1250 masl, 1251-1300 masl, 1301-1350 masl, respectively, followed by 1st, 2nd and 3rd week of May in 1351-1400 masl, 1401-1450 masl, 1451-1500 masl, respectively. Morphometrics of Chinese citrus fly such as weight, length and width of pupa and adult were almost similar to the species collecte...

International Journal of Entomology Research, 2021

Journal of the Plant Protection Society

Morphometric study of adult Chinese citrus fly, Bactrocera minax (Enderlein) was carried out on M... more Morphometric study of adult Chinese citrus fly, Bactrocera minax (Enderlein) was carried out on May, 2020 at Sindhuli, Nepal. The mean body length of female recorded significantly higher, 14.29 ± 0.20 mm, than male, 12.52 ± 0.26 mm, with the mean difference of 1.77 mm (p = ≤ 0.001). Females had a wider body (3.90 ± 0.06 mm) compared to males (3.39 ± 0.05 mm) (p = ≤ 0.001) which differed significantly by 0.51 mm. Adult female possessed a wider wingspan, i.e. 23.51 ± 0.23 mm significantly different than adult male, i.e. 22.80 ± 0.19 mm with the mean difference of 0.71 mm (p = ≤ 0.05). Similarly, the average wing length measured 8.82 ± 0.13mm in male and 9.05 ± 0.11 mm in female with the mean difference of 0.23 mm. The ovipositor length recorded 4.52 ± 0.12 mm. This information is useful to distinguish between Chinese citrus fly and other fruit fly species of citrus orchards and useful in planning of the suitable management options.

Journal of Agriculture and Environment

Chinese citrus fly, Bactrocera minax (Enderlein) (Diptera: Tephritidae) is one of the important ... more Chinese citrus fly, Bactrocera minax (Enderlein) (Diptera: Tephritidae) is one of the important citrus pests in Nepal, India and Bhutan including China where it was originated. Since 2014/15, the problem of B. minax in sweet orange fruit is being faced by citrus growers in Sindhuli, Nepal. To mitigate the problem of B. minax, Chinese citrus fly in the orchards, afield practice of area wide control program (AWCP) was piloted in the selected 231 citrus orchards for the first time in Sindhuli in 2018 which has been adopted by 1153 citrus growers in 2019. The obvious recessions of mean fruit damage percentages due to B. minax in the sweet orange orchards at different locations in 2018 (range: 3.9 ± 1.1% to 29.7 ± 9.6%) and 2019 (range: 2.6 ± 0.8% to 7.5 ± 2.3%) have been achieved by virtue of B. minax management through AWCP with poisonous protein bait component and sanitation measure in the citrus orchards.

International Journal of Environment, 2020

Carnation (Dianthus caryophyllus L.) is one of the most commercially important cut flowers of the... more Carnation (Dianthus caryophyllus L.) is one of the most commercially important cut flowers of the world. It can be used for cut flowers, bedding, edging, boarders, pots and rock garden. Four Spanish carnation varieties were tested with three levels of boron under ultra-violet stabilized polytunnels from August 2017 to April 2018 at Godawari, Nepal. The objective of the research was to evaluate vegetative, floral, and vase life parameters in relations to growth, yield and quality of carnation. The research was conducted in a randomized complete block design with 3 replications. The variety Baltico had the maximum leaf length (19.3 cm), numbers of lateral branches (10.5), internodal length (5.1 cm), flower diameter (8.6 cm), and vase life (24.0 days). The numbers of nodes (5) and flower weight (25.4 g) were highest in the variety Vinco with the lowest cracked area on the stem (0.2 cm2/ crack). The numbers of stem cracks per plant significantly (p ≤0.01) reduced with an increasing leve...

Nepalese Horticulture, 2020

Chinese citrus fly, Bactrocera minax (Enderlein), is one of the most important pests of citrus. T... more Chinese citrus fly, Bactrocera minax (Enderlein), is one of the most important pests of citrus. The pest is more problematic in the eastern part of the country, Nepal. Because of the difficulties associated with the control of this pest by chemical insecticides, farmers had experienced great losses in Sweet Orange. Therefore, a participatory field survey was conducted under farmer field conditions to assess losses and measure the efficacy of different local and recommended management options to address the problem of this pest. Study consisted of two major parts: monitoring of pest population and farmer’s survey. For monitoring three orchards were selected located at different altitude i.e. 1200 masl, 1300 masl and 1400 masl. Great Fruit fly Bait (25% protein hydrolysate and 0.1% abamectin) in McPhail traps were used for monitoring. Monitoring was done in every 7 days interval and lures were changed in every 15 days for the effectiveness. Only 18.3% farmers were using protein bait f...

Archives of Agriculture and Environmental Science, 2020

Unlike other Tephrid flies, the Chinese citrus fly (Bactrocera minax Enderlein) is univoltine and... more Unlike other Tephrid flies, the Chinese citrus fly (Bactrocera minax Enderlein) is univoltine and oligophagous species strictly restricted to citrus fruits. It has been a serious threat to the citrus industry in China, Bhutan, India and Nepal causing up to 100% of fruit drop before the harvest. Citrus groves, especially tight-skinned cultivars, sweet orange (Citrus sinensis L. Osbeck) in mid-hill districts like Ramechhap, Sindhuli, Dolakha, Kavre, Syangja, Gulmi, etc. have been threatened while in some pockets, lemon, acid lime, and mandarin have vanished due to the Chinese citrus fly (CCF). The driver behind the spread of this invasive pest seems to be poor research works on the phenology of the pest, ill-equipped management practices, flying nature of adult fly and easy movement of infested fruits. Therefore, with reviewing published data, this study aimed to figure out the most appropriate management technology for curbing the CCF and make comprehensive material for safeguarding ...

American Journal of Agricultural and Biological Sciences, 2020

Citrus plays a significant role in providing nutrition to people and generating income for the ci... more Citrus plays a significant role in providing nutrition to people and generating income for the citrus farmers in Nepal. Among various biotic problems in citriculture, Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) (Diptera: Tephritidae) has become a major threat to the production of the tight skin citrus fruits, viz. sweet orange, lemon and lime in recent years. This invasive species originated in China and seems to have entered into northeastern Nepal through Bhutan and Sikkim (India). The damage to sweet orange (Citrus sinensis (L.) Osbeck) by CCF has shown a yearly increasing pattern since 2014 in the central hilly citrus orchards in the districts of Sindhuli and Ramechhap. Sindhuli district holds the first position in terms of sweet orange acreage and its production in Nepal. Conventional pest control measures including pesticide cover spray seemed to have resulted in limited effect in controlling CCF. Thus, as a pilot program, an Area-Wide Control Program (AWCP) of this pest was conducted in 40 ha of sweet orange orchards at Golanjor Rural Municipality-4, Tinkanya in Sindhuli, Nepal to minimize the fruit damages by maggots of B. minax. AWCP focused on the life cycle based management strategy of this pest, targeting the female adult fly population. Formulated protein bait (Great Fruit Fly Bait) containing 25% protein hydrolysate and 0.1% Abamectin was used as spot application underside of the 0.5 to 1 m 2 leaf for 10 times at a weekly interval from May to July 2018 as per the protocol developed by Ecoman Biotech, China. The result revealed that the leaf underside spot treatment with the protein bait was highly efficient to minimize the sweet orange fruit losses from 56.7 to 10.9%. Coordination among stakeholders along with sound technical aspect and managerial function seemed essential for the successful implementation of B. minax AWCP.

Journal of Natural History Museum, 2018

Protocol based fruit fly surveillance made in 2014-15 in citrus orchards in Sindhuli district rev... more Protocol based fruit fly surveillance made in 2014-15 in citrus orchards in Sindhuli district revealed six species of Bactrocera flies, namely Bactrocera minax (Enderlein), B. cucurbitaeCoquillett, B. dorsalis (Hendel), B. zonata (Saunders), B. tau Walker and B. scutellaris (Bezzi),and one species of Dacus longicornis Weidman. Except B. minax, other fruit flies we recollected in male lure traps, while B. minax fruit flies were also reared to adults from infested sweet oranges. Each species of fruit flies has been morphologically identified up to species level for field identification purpose. D. longicornis is reported for the first time from Nepal.

Acta agraria Debreceniensis, Jun 3, 2024

Journal of Agriculture and Environment

Problems of Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) in citrus orchards have been i... more Problems of Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) in citrus orchards have been increasing in Nepal. The reason behind the failure in CCF control is the lack of a clear and thorough understanding of the adult emergence period in different altitudes. Therefore, the pupae of CCF were collected from the soil below the infested sweet orange trees in Sunapati Rural Municipality, Ramechhap, Nepal and reared in containers of height 5 cm and diameter 6 cm (10 pupae per container) in randomized complete block design selecting different locations as treatments, viz. 1247 masl (Bethan), 1354 masl (Nagsiwa), 1443 masl (Aarukharka), 1561 masl (Sadi), 1650 masl (Dimipokhari) replicating four times. Early peak emergences of adult CCF (four weeks earlier in 4th week of April) occurred at lower altitudes as compared to the higher altitudes (in 4th week of May), where peak-emergence was recorded. Male: female ratio (range 1.05-1.37) did not differ significantly at different altitudes,...

Journal of the Institute of Agriculture and Animal Science

Chinese citrus fly is the major pest of sweet orange in citrus growing districts of Bagmati Provi... more Chinese citrus fly is the major pest of sweet orange in citrus growing districts of Bagmati Province Nepal. Farmer’s production constrains and production problems such as Chinese citrus fly problem in sweet orange are not well documented and studied. This study was conducted in Sindhuli, Ramechhap, Dolakha and Kavre districts of Bagmati Province in 2021 with aim to understand the farmer’s perception, knowledge about CCF and their management practices using semi-structured questionnaire. Collected survey data was analyzed using the SPSS-20 and MS Excel. The survey results depicted that the intensity of Chinese citrus fly damage has been decreased in Sindhuli district with the infestation level of < 20% in sweet orange orchard. However, CCF population as well as their damage level was in increasing trend of > 50% in sweet orange orchard in Ramechhap, and > 80% in Dolakha and Kavre district. Chinese citrus fly loss has been recorded up to 25% in Mandarin orange in Dolakha and ...

Journal of the Plant Protection Society

Fruit flies (Diptera: Tephritidae) are devastating pests in citrus orchards of Nepal causing huge... more Fruit flies (Diptera: Tephritidae) are devastating pests in citrus orchards of Nepal causing huge losses of fruits. A farmer's survey was carried from March to December, 2021 randomly selecting 40 citrus orchard owners, and at the same time, a field monitoring of fruit flies organised in randomized complete block design with 7 times replicated 3 treatments (Cue lure and malathion in Steiner trap, Methyl eugenol and malathion in Steiner trap and protein bait in McPhail trap) were conducted in Ramechhap district of Nepal. Survey revealed that Chinese citrus fly was the most problematic insect pest of citrus orchard. However, only few farmers were practising effective control measures against this pest. Nine species of fruit flies were trapped in different lures and protein bait, when the number of fruit flies differed significantly (p<0.05) except Bactrocera correcta and Zeugodacus cucurbitae, which were found attracted in negligible number in Methyl eugenol and Cue lure, respe...

Journal of the Plant Protection Society

Chinese citrus fly, Bactrocera minax (Enderlein) is a major pest of citrus fruits that causes sig... more Chinese citrus fly, Bactrocera minax (Enderlein) is a major pest of citrus fruits that causes significant fruit losses in citrus orchards in Nepal, China, Bhutan and India. In 2021, a field study was conducted to know the oviposition period of this pest in a sweet orange orchard in Sindhuli, Nepal. The pest deposits its eggs on 25-50 mm citrus fruits during June-July. The timing of egg laying is crucial in designing and deploy adult fly management such as protein bait in citrus orchards.

Fundamental and Applied Agriculture

The study was conducted to access the species diversity of fruit fly and their population dynamic... more The study was conducted to access the species diversity of fruit fly and their population dynamics, awareness among mandarin growers on the nature of damage, and factors affecting the awareness in the Jajarkot district of Nepal in 2021. The study consists of two parts: farmer’s survey and monitoring of fruit flies. The farmer’s survey was carried out in randomly selected sixty households whose orchards were at least five years old in command areas of citrus zone, Jajarkot. Fruit fly monitoring was done in three mandarin orchards of Kushe Rural Municipality and Bheri Municipality using cue-lure, methyl eugenol, and great fruit fly bait. The survey revealed that only thirty percent of the farmers were aware of the nature of fruit fly damage. Experience in mandarin cultivation was found to be significantly affecting the awareness of mandarin growers on fruit fly damage. The mandarin growers were practicing pruning, collection and destruction of fallen fruits, use of chemicals, and trap...

Journal of the Plant Protection Society

The study was carried out from April-August, 2017 to monitor the population of Tuta absoluta and ... more The study was carried out from April-August, 2017 to monitor the population of Tuta absoluta and to assess the management practices being adopted in Kavre, Nepal. Study consisted of two major parts: monitoring of insect population and farmer’s survey. The population of T. absoluta ranged from 51 to 972 in each Wota -T trap. The highest population of the insect in traps were recorded in Dhulikhel followed by Panauti and Banepa. Majority of tomato growers (78%) reported T. absoluta as the most problematic among other pests, diseases and disorders. The data from E-Plant clinic at Panchkhal revealed the degree of severity of T. absoluta in tomato crop. Tomato growers have adopted cultural, physical, mechanical, para-pheromone lures, quarantine, botanical and chemical methods for the management of this pest. Majority of them relied on chemical pesticide (94%) followed by cultural practices (86%) and Tomato Leaf Miner (TLM) lure (66%) based on cumulative percentage of respondents. Use of ...

Journal of the Plant Protection Society

Agricultural production has been challenged by various biotic and abiotic factors in Nepal. Losse... more Agricultural production has been challenged by various biotic and abiotic factors in Nepal. Losses incurred by different insect pests and diseases are remarkable. As a counter measure, Government of Nepal has implemented various activities through extension, research and academic institutions. Integrated Pest Management (IPM) has been the central approach of plant protection in Nepal. It was initiated in 1997 with an aim to reduce the excessive and injudicious use of chemical pesticides to enhance the crop production, paying due attention on gender mainstreaming, and social inclusion. Besides, plant clinic program is gaining popularity in Nepal to provide plant health extension advisory services. Being a signatory country of Rotterdam Convention and Stockholm Convention, Nepal has imposed ban on sixteen different types of chemical pesticides including persistent organic pollutants (POPs). Botanicals and bio-pesticides are also used in agriculture to manage pests and diseases of crop...

Journal of Agriculture and Environment, 2019

Nepal Journal of Science and Technology, 2015

A field investigation was carried out during July 2008 to April 2009 in a farmer’s field at Gunja... more A field investigation was carried out during July 2008 to April 2009 in a farmer’s field at Gunjanagar-5, Chitwan, Nepal to evaluate the influence of time and intensity of pruning on growth and flowering behaviour of cut rose cv. Super Tata (Rosa hybrida). The experiment was laid out in a completely randomized block design with nine treatment combinations and replicated thrice. The treatments comprised of three dates of pruning i.e. 30th July, 15th August and 30th August and three pruning intensities i.e. heavy (6 buds per plant), medium (12 buds per plant) and light (18 buds per plant). Both time and intensity of pruning significantly affected growth and yield attributing parameters. The plants pruned heavily on 30th July produced highest plant height, number, length and diameter of canes. Similarly, stem bud as well as floral initiation were also earlier as compared to other treatments. On the other hand, fresh and dry weight of leaf and leaf area index were highest from the plant...

International Journal of Environment

Chinese citrus fly, Bactrocera minax is a destructive and univoltine pest of citrus fruits. Geogr... more Chinese citrus fly, Bactrocera minax is a destructive and univoltine pest of citrus fruits. Geographical altitudinal gradients as well as prevailing climate affect the biology and ecology of insect. Hence, this study aimed to ascertain the effect of altitude on the adult emergence and morphological variations in various ecological settings of Ramechhap district of Nepal from February to June 2021 in citrus orchard. Six altitude ranges were selected in 50 m distance from 1200 to 1500 m above sea level (masl), ranging from 1201-1250 masl, 1251-1300 masl, 1301-1350 masl, 1351-1400 masl, 1401-1450 masl and 1451-1500 masl. The peak adult emergence periods were the 2nd, 3rd, 4th week of April in 1201-1250 masl, 1251-1300 masl, 1301-1350 masl, respectively, followed by 1st, 2nd and 3rd week of May in 1351-1400 masl, 1401-1450 masl, 1451-1500 masl, respectively. Morphometrics of Chinese citrus fly such as weight, length and width of pupa and adult were almost similar to the species collecte...

International Journal of Entomology Research, 2021

Journal of the Plant Protection Society

Morphometric study of adult Chinese citrus fly, Bactrocera minax (Enderlein) was carried out on M... more Morphometric study of adult Chinese citrus fly, Bactrocera minax (Enderlein) was carried out on May, 2020 at Sindhuli, Nepal. The mean body length of female recorded significantly higher, 14.29 ± 0.20 mm, than male, 12.52 ± 0.26 mm, with the mean difference of 1.77 mm (p = ≤ 0.001). Females had a wider body (3.90 ± 0.06 mm) compared to males (3.39 ± 0.05 mm) (p = ≤ 0.001) which differed significantly by 0.51 mm. Adult female possessed a wider wingspan, i.e. 23.51 ± 0.23 mm significantly different than adult male, i.e. 22.80 ± 0.19 mm with the mean difference of 0.71 mm (p = ≤ 0.05). Similarly, the average wing length measured 8.82 ± 0.13mm in male and 9.05 ± 0.11 mm in female with the mean difference of 0.23 mm. The ovipositor length recorded 4.52 ± 0.12 mm. This information is useful to distinguish between Chinese citrus fly and other fruit fly species of citrus orchards and useful in planning of the suitable management options.

Journal of Agriculture and Environment

Chinese citrus fly, Bactrocera minax (Enderlein) (Diptera: Tephritidae) is one of the important ... more Chinese citrus fly, Bactrocera minax (Enderlein) (Diptera: Tephritidae) is one of the important citrus pests in Nepal, India and Bhutan including China where it was originated. Since 2014/15, the problem of B. minax in sweet orange fruit is being faced by citrus growers in Sindhuli, Nepal. To mitigate the problem of B. minax, Chinese citrus fly in the orchards, afield practice of area wide control program (AWCP) was piloted in the selected 231 citrus orchards for the first time in Sindhuli in 2018 which has been adopted by 1153 citrus growers in 2019. The obvious recessions of mean fruit damage percentages due to B. minax in the sweet orange orchards at different locations in 2018 (range: 3.9 ± 1.1% to 29.7 ± 9.6%) and 2019 (range: 2.6 ± 0.8% to 7.5 ± 2.3%) have been achieved by virtue of B. minax management through AWCP with poisonous protein bait component and sanitation measure in the citrus orchards.

International Journal of Environment, 2020

Carnation (Dianthus caryophyllus L.) is one of the most commercially important cut flowers of the... more Carnation (Dianthus caryophyllus L.) is one of the most commercially important cut flowers of the world. It can be used for cut flowers, bedding, edging, boarders, pots and rock garden. Four Spanish carnation varieties were tested with three levels of boron under ultra-violet stabilized polytunnels from August 2017 to April 2018 at Godawari, Nepal. The objective of the research was to evaluate vegetative, floral, and vase life parameters in relations to growth, yield and quality of carnation. The research was conducted in a randomized complete block design with 3 replications. The variety Baltico had the maximum leaf length (19.3 cm), numbers of lateral branches (10.5), internodal length (5.1 cm), flower diameter (8.6 cm), and vase life (24.0 days). The numbers of nodes (5) and flower weight (25.4 g) were highest in the variety Vinco with the lowest cracked area on the stem (0.2 cm2/ crack). The numbers of stem cracks per plant significantly (p ≤0.01) reduced with an increasing leve...

Nepalese Horticulture, 2020

Chinese citrus fly, Bactrocera minax (Enderlein), is one of the most important pests of citrus. T... more Chinese citrus fly, Bactrocera minax (Enderlein), is one of the most important pests of citrus. The pest is more problematic in the eastern part of the country, Nepal. Because of the difficulties associated with the control of this pest by chemical insecticides, farmers had experienced great losses in Sweet Orange. Therefore, a participatory field survey was conducted under farmer field conditions to assess losses and measure the efficacy of different local and recommended management options to address the problem of this pest. Study consisted of two major parts: monitoring of pest population and farmer’s survey. For monitoring three orchards were selected located at different altitude i.e. 1200 masl, 1300 masl and 1400 masl. Great Fruit fly Bait (25% protein hydrolysate and 0.1% abamectin) in McPhail traps were used for monitoring. Monitoring was done in every 7 days interval and lures were changed in every 15 days for the effectiveness. Only 18.3% farmers were using protein bait f...

Archives of Agriculture and Environmental Science, 2020

Unlike other Tephrid flies, the Chinese citrus fly (Bactrocera minax Enderlein) is univoltine and... more Unlike other Tephrid flies, the Chinese citrus fly (Bactrocera minax Enderlein) is univoltine and oligophagous species strictly restricted to citrus fruits. It has been a serious threat to the citrus industry in China, Bhutan, India and Nepal causing up to 100% of fruit drop before the harvest. Citrus groves, especially tight-skinned cultivars, sweet orange (Citrus sinensis L. Osbeck) in mid-hill districts like Ramechhap, Sindhuli, Dolakha, Kavre, Syangja, Gulmi, etc. have been threatened while in some pockets, lemon, acid lime, and mandarin have vanished due to the Chinese citrus fly (CCF). The driver behind the spread of this invasive pest seems to be poor research works on the phenology of the pest, ill-equipped management practices, flying nature of adult fly and easy movement of infested fruits. Therefore, with reviewing published data, this study aimed to figure out the most appropriate management technology for curbing the CCF and make comprehensive material for safeguarding ...

American Journal of Agricultural and Biological Sciences, 2020

Citrus plays a significant role in providing nutrition to people and generating income for the ci... more Citrus plays a significant role in providing nutrition to people and generating income for the citrus farmers in Nepal. Among various biotic problems in citriculture, Chinese Citrus Fly (CCF), Bactrocera minax (Enderlein) (Diptera: Tephritidae) has become a major threat to the production of the tight skin citrus fruits, viz. sweet orange, lemon and lime in recent years. This invasive species originated in China and seems to have entered into northeastern Nepal through Bhutan and Sikkim (India). The damage to sweet orange (Citrus sinensis (L.) Osbeck) by CCF has shown a yearly increasing pattern since 2014 in the central hilly citrus orchards in the districts of Sindhuli and Ramechhap. Sindhuli district holds the first position in terms of sweet orange acreage and its production in Nepal. Conventional pest control measures including pesticide cover spray seemed to have resulted in limited effect in controlling CCF. Thus, as a pilot program, an Area-Wide Control Program (AWCP) of this pest was conducted in 40 ha of sweet orange orchards at Golanjor Rural Municipality-4, Tinkanya in Sindhuli, Nepal to minimize the fruit damages by maggots of B. minax. AWCP focused on the life cycle based management strategy of this pest, targeting the female adult fly population. Formulated protein bait (Great Fruit Fly Bait) containing 25% protein hydrolysate and 0.1% Abamectin was used as spot application underside of the 0.5 to 1 m 2 leaf for 10 times at a weekly interval from May to July 2018 as per the protocol developed by Ecoman Biotech, China. The result revealed that the leaf underside spot treatment with the protein bait was highly efficient to minimize the sweet orange fruit losses from 56.7 to 10.9%. Coordination among stakeholders along with sound technical aspect and managerial function seemed essential for the successful implementation of B. minax AWCP.

Journal of Natural History Museum, 2018

Protocol based fruit fly surveillance made in 2014-15 in citrus orchards in Sindhuli district rev... more Protocol based fruit fly surveillance made in 2014-15 in citrus orchards in Sindhuli district revealed six species of Bactrocera flies, namely Bactrocera minax (Enderlein), B. cucurbitaeCoquillett, B. dorsalis (Hendel), B. zonata (Saunders), B. tau Walker and B. scutellaris (Bezzi),and one species of Dacus longicornis Weidman. Except B. minax, other fruit flies we recollected in male lure traps, while B. minax fruit flies were also reared to adults from infested sweet oranges. Each species of fruit flies has been morphologically identified up to species level for field identification purpose. D. longicornis is reported for the first time from Nepal.