The Experts below are selected from a list of 1131 Experts worldwide ranked by ideXlab platform
Takahisa Miyatake - One of the best experts on this subject based on the ideXlab platform.
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faster or slower developers have a shorter or longer circadian period in Bactrocera cucurbitae
Physiological Entomology, 2017Co-Authors: Takahisa MiyatakeAbstract:A clock controlling circadian rhythm may relate to another clock controlling development time. The relationship between the two clocks remains open to discussion. Genetic correlation between developmental and circadian periods is observed in two Dipteran species (Bactrocera cucurbitae and Drosophila melanogaster), whereas it is not observed in a Coleopteran species (Callosobruchus chinensis). No studies, however, are available that report on the phenotypic correlation between the two traits. In the present study, free-running circadian periods are compared between individuals that develop fastest and slowest within a population of B. cucurbitae. The measurement of circadian periods is replicated using five populations of B. cucurbitae with different geographical and rearing histories. The results demonstrate that the flies developing more slowly have significantly longer circadian periods compared with the flies developing more quickly in two of five populations examined in B. cucurbitae, and thus the phenotypic correlation is dependent on population.
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the clock gene cryptochrome of Bactrocera cucurbitae diptera tephritidae in strains with different mating times
Heredity, 2010Co-Authors: Taro Fuchikawa, Masaaki Yamagishi, Akira Matsumoto, Takashi Matsuyama, Teiichi Tanimura, S Sanada, R Nishio, Kenji Tomioka, Takahisa MiyatakeAbstract:Differences in mating time between populations can give rise to premating reproductive isolation. Tephritid fruit flies exhibit large variation in mating time among intra- or inter-specific populations. We previously cloned the clock gene period from two strains of melon fly, Bactrocera cucurbitae; in one the individuals mate early during the day, whereas in the other the individuals mate later. These strains were originally established by divergent artificial selection for developmental time, ‘short’ and ‘long’, with early and late mating times, respectively. The deduced amino acid sequences of PERIOD proteins for these two strains were reported to be identical. Here we cloned another clock gene cryptochrome (cry) from the two strains, and found two stable amino acid substitutions in the strains. In addition, the allele frequency at the two polymorphic sites of cry gene correlated with the circadian locomotor period (τ) across strains, whereas the expression pattern of cry mRNA in the heads of flies taken from the short strain significantly differed from that from the long strain. These findings suggest that variation in the cry gene is related to differences in the circadian behaviour in the two strains, thus implying that the cry gene may have an important role in reproductive isolation.
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male courtship song in circadian rhythm mutants of Bactrocera cucurbitae tephritidae diptera
Journal of Insect Physiology, 2004Co-Authors: Takahisa Miyatake, Kenkichi KanmiyaAbstract:Pulse train intervals (PTI) of courtship song were differentiated between circadian clock mutants of the melon fly, Bactrocera cucurbitae (Coquillett) (Tephritidae: Diptera). We analysed the male mating song of B. cucurbitae flies of two mutant strains that differed in circadian locomotor rhythm by a LabVIEW programming system. Flies with a short circadian rhythm (S-strain) had shorter PTI than those with a long circadian rhythm (L-strain) in the two age groups tested, young and old. Young flies showed longer PTI than old flies, but no interaction between strain and age was found in PTI. There was a significant interaction between strain and age for pulse train duration (PTD), whereas no stable difference was found in PTD between S- and L-strains. These results suggest a positive correlation between the length of the circadian locomotor rhythm and PTI of courtship song sounds in B. cucurbitae.
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eradication of the melon fly Bactrocera cucurbitae in japan importance of behavior ecology genetics and evolution
Annual Review of Entomology, 2004Co-Authors: Juro Koyama, Hiroyuki Kakinohana, Takahisa MiyatakeAbstract:The melon fly, Bactrocera cucurbitae, is a destructive insect of cucurbit and other fruits. It invaded the Southwestern Islands of Japan from 1919 to 1974. The sterile insect technique (SIT) was successfully applied from 1972 to 1993 to eradicate the melon fly. Technical research into SIT functions, such as suppression of density, mass-rearing, sterilization, shipment, release, evaluation of efficacy, and quality control of mass-reared insects, was conducted for this eradication project. Fundamental research into the dispersion, mating and oviposition behavior, population dynamics and estimation of density, eradication models, spatial distribution, genetics, and evolution of the melon fly was also undertaken and supported the success of the eradication project.
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The period gene and allochronic reproductive isolation in Bactrocera cucurbitae.
Proceedings. Biological sciences, 2002Co-Authors: Takahisa Miyatake, Akira Matsumoto, Takashi Matsuyama, Hiroki R. Ueda, Tetsuya Toyosato, Teiichi TanimuraAbstract:Clock genes that pleiotropically control circadian rhythm and the time of mating may cause allochronic reproductive isolation in the melon fly Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). Flies with a shorter circadian period (ca. 22 h of locomotor activity rhythm) mated 5 h earlier in the day than those with a longer circadian period (ca. 30 h). Mate-choice tests demonstrated significant pre-mating isolation between populations with short and long circadian periods. Pre-mating isolation did not occur when the mating time was synchronized between the two populations by photoperiodic controls, indicating that reproductive isolation is due to variations in the time of mating and not any unidentified ethological difference between the two populations. We cloned the period (per) gene of B. cucurbitae that is homologous to the per gene in Drosophila. The relative level of per mRNA in the melon fly exhibited a robust daily fluctuation under light : dark conditions. The fluctuation of per expression under dark : dark conditions is closely correlated to the locomotor rhythm in B. cucurbitae. These results suggest that clock genes can cause reproductive isolation via the pleiotropic effect as a change of mating time.
Nripendra Laskar - One of the best experts on this subject based on the ideXlab platform.
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fruit infestation and larval density of melon fly Bactrocera cucurbitae coq as influenced by morphological traits of bitter gourd momordica charantia l
International journal of Bio-resource and Stress Management, 2013Co-Authors: Nripendra Laskar, Hirak ChatterjeeAbstract:Melon fly, Bactrocera cucurbitae (Coq.) (Diptera: Tephritidae) is one of the most important biotic constraints for reaping optimum yield potentiality of cucurbitaceous crops. Due to its peculiar life history and mode of damage it is very much difficult to manage the pest by implementing conventional tactics. Thus, it is important to search for plant characteristics that are associated with survivability and development of the pest. Ten bitter gourd cultivars including open pollinated, hybrids and local accessions were taken to study the effect of morphological traits on fruit infestation and larval density of melon fly. There exist significant variation in percent fruit infestation and larval density per infested fruit in different test cultivars and were correlated positively (r=0.48). Positive correlation of percent fruit infestation and larval density per fruit were derived with fruit weight (r=0.76 and 0.75), length (r=0.71 and 0.72) and diameter (r=0.68 and 0.60). On the contrary, negative correlation were observed with ribs density (r=-0.78 and -0.73), ribs depth (r=-0.24 and -0.18) and skin toughness (r=-0.80 and -0.84) of fruits. Multiple correlations on the impact of morphological traits of fruits on percent fruit infestation and larval density fruit−1 were also derived.
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biology and biometrics of melon fruit fly Bactrocera cucurbitae coq on bitter gourd momordica charantia l and pumpkin cucurbita pepo l
Current Biotica, 2013Co-Authors: Nripendra LaskarAbstract:Biology and biometrics of melon fly, Bactrocera cucurbitae (Coq.) was studied on bitter gourd and pumpkin fruit under laboratory conditions (temperature 26 o C- 30 o C and relative humidity 70-75%) at the, Uttar Banga Krishi Viswavidyalaya, West Bengal, India during 200708. Findings of the study revealed that average length and breadth of egg was more or less similar when reared on bitter gourd and pumpkin (1.28 ± 0.059 mm, 0.26±0.057mm and 1.26 ±0.060 mm, 0.25±0.053mm, respectively). The length of mature maggots also does not show much variation on both the hosts whereas weight of mature maggots was found to be slightly higher in bitter gourd as compared to that of pumpkin. Similarly length and breadth of pre-pupal stage was also noted slightly higher on bitter gourd (6.89±0.46mm. and 2.04±0.23mm. respectively) that pumpkin (6.70±0.60mm. and 1.99±0.22mm. respectively). In both bitter gourd and pumpkin, size of the females was larger than the males. Fecundity and hatchability were noted very close on bitter gourd (138.40±44.05 and 86.40±7.09% respectively) and pumpkin (135.60±33.04 and 89.60±6.07% respectively). Sex ratio (male : female) was recorded 1.102±0.136 and 0.976±0.104 on bitter gourd and pumpkin, respectively.
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field evaluation of bait components in attracting melon fly Bactrocera cucurbitae coq tephritidae diptera in sub himalayan foot hills of north eastern india
Pakistan Entomologist, 2010Co-Authors: Nripendra Laskar, Hirak ChatterjeeAbstract:Efficacy of some locally available food lures such as molasses, sugar, country liquor and date palm juice (fresh and fermented) as bait components in attracting melon fly, Bactrocera cucurbitae (Coq.) were tested. Cypermthrin 10EC, chlorpyrifos 20 EC, spinosad 45SC, malathion 50EC, chlorpyrifos 50% + cypermethrin 5% and endosulfan 35 EC in cuelure bait were also used in bucket trap in a separate experiments. Both trials were conducted at the field of Instructional Farm, Uttar Banga Krishi Viswavidyalaya, Cooch Behar, West Bengal, India during 2007-2008. Results showed that the number of adult flies attracted per bait per day varied significantly in different baits being highest (3.22) in molasses followed by fermented date palm juice (3.18) and country liquor (2.11), whereas the lowest (0.67) was recorded in sugar. Highest number of flies was trapped in malathion traps (12.33) which had non-significant difference with chlorpyrifos + cypermethrin (11.67) and spinosad (10.67). Initial high number of flies trapped in various traps in both experiments decreased gradually over time.
Hirak Chatterjee - One of the best experts on this subject based on the ideXlab platform.
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fruit infestation and larval density of melon fly Bactrocera cucurbitae coq as influenced by morphological traits of bitter gourd momordica charantia l
International journal of Bio-resource and Stress Management, 2013Co-Authors: Nripendra Laskar, Hirak ChatterjeeAbstract:Melon fly, Bactrocera cucurbitae (Coq.) (Diptera: Tephritidae) is one of the most important biotic constraints for reaping optimum yield potentiality of cucurbitaceous crops. Due to its peculiar life history and mode of damage it is very much difficult to manage the pest by implementing conventional tactics. Thus, it is important to search for plant characteristics that are associated with survivability and development of the pest. Ten bitter gourd cultivars including open pollinated, hybrids and local accessions were taken to study the effect of morphological traits on fruit infestation and larval density of melon fly. There exist significant variation in percent fruit infestation and larval density per infested fruit in different test cultivars and were correlated positively (r=0.48). Positive correlation of percent fruit infestation and larval density per fruit were derived with fruit weight (r=0.76 and 0.75), length (r=0.71 and 0.72) and diameter (r=0.68 and 0.60). On the contrary, negative correlation were observed with ribs density (r=-0.78 and -0.73), ribs depth (r=-0.24 and -0.18) and skin toughness (r=-0.80 and -0.84) of fruits. Multiple correlations on the impact of morphological traits of fruits on percent fruit infestation and larval density fruit−1 were also derived.
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field evaluation of bait components in attracting melon fly Bactrocera cucurbitae coq tephritidae diptera in sub himalayan foot hills of north eastern india
Pakistan Entomologist, 2010Co-Authors: Nripendra Laskar, Hirak ChatterjeeAbstract:Efficacy of some locally available food lures such as molasses, sugar, country liquor and date palm juice (fresh and fermented) as bait components in attracting melon fly, Bactrocera cucurbitae (Coq.) were tested. Cypermthrin 10EC, chlorpyrifos 20 EC, spinosad 45SC, malathion 50EC, chlorpyrifos 50% + cypermethrin 5% and endosulfan 35 EC in cuelure bait were also used in bucket trap in a separate experiments. Both trials were conducted at the field of Instructional Farm, Uttar Banga Krishi Viswavidyalaya, Cooch Behar, West Bengal, India during 2007-2008. Results showed that the number of adult flies attracted per bait per day varied significantly in different baits being highest (3.22) in molasses followed by fermented date palm juice (3.18) and country liquor (2.11), whereas the lowest (0.67) was recorded in sugar. Highest number of flies was trapped in malathion traps (12.33) which had non-significant difference with chlorpyrifos + cypermethrin (11.67) and spinosad (10.67). Initial high number of flies trapped in various traps in both experiments decreased gradually over time.
Scott M Geib - One of the best experts on this subject based on the ideXlab platform.
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population genomics and comparisons of selective signatures in two invasions of melon fly Bactrocera cucurbitae diptera tephritidae
Biological Invasions, 2018Co-Authors: Luc Leblanc, Julian R Dupuis, Sheina B Sim, Michael San Jose, Aftab M Hoassain, Daniel Rubinoff, Scott M GeibAbstract:Population genetics is a powerful tool for invasion biology and pest management, and useful for a range of questions from tracing invasion pathways to informing management decisions with inference of population demographics. Genomics greatly increases the resolution of population-scale analyses, yet outside of model species with extensive genomic resources, few studies have used population genomics in invasion biology. We use genome-wide single nucleotide polymorphisms (SNPs) to investigate population genomic structure with samples from across the range of melon fly, Bactrocera cucurbitae (Coquillett, 1849), a highly polyphagous pest of commercial produce. We then make use of a chromosome-scale genome assembly and gene set to compare signatures of selection across the melon fly’s genome, both across our sampling as a whole and in the context of two independent, established introductions. Using multiple approaches, we find support for six genetic clusters across melon fly’s distribution. Some of these agree with previously identified genetic clusters using microsatellites, but consensus of clusters in mainland and oceanic southeast Asia is confounded by variable sampling between studies. We find few adaptive signatures across the genome, and virtually no unique signatures when comparing the two independent introductions, which suggests that similar management strategies are appropriate across melon fly’s range. This is the first use of genome-wide data to characterize population structure in tephritid fruit fly pests, and our SNP dataset provides a foundation for objective and cost-effective genotyping of previously collected melon fly specimens. Future research needs to focus on truly comprehensive sampling across melon fly’s range to overcome the historic variability of range-wide estimates of population structure for this pest.
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a chromosome scale assembly of the Bactrocera cucurbitae genome provides insight to the genetic basis of white pupae
G3: Genes Genomes Genetics, 2017Co-Authors: Sheina B Sim, Scott M GeibAbstract:Genetic sexing strains (GSS) used in sterile insect technique (SIT) programs are textbook examples of how classical Mendelian genetics can be directly implemented in the management of agricultural insect pests. Although the foundation of traditionally developed GSS are single locus, autosomal recessive traits, their genetic basis are largely unknown. With the advent of modern genomic techniques, the genetic basis of sexing traits in GSS can now be further investigated. This study is the first of its kind to integrate traditional genetic techniques with emerging genomics to characterize a GSS using the tephritid fruit fly pest Bactrocera cucurbitae as a model. These techniques include whole-genome sequencing, the development of a mapping population and linkage map, and quantitative trait analysis. The experiment designed to map the genetic sexing trait in B. cucurbitae, white pupae (wp), also enabled the generation of a chromosome-scale genome assembly by integrating the linkage map with the assembly. Quantitative trait loci analysis revealed SNP loci near position 42 MB on chromosome 3 to be tightly linked to wp. Gene annotation and synteny analysis show a near perfect relationship between chromosomes in B. cucurbitae and Muller elements A–E in Drosophila melanogaster. This chromosome-scale genome assembly is complete, has high contiguity, was generated using a minimal input DNA, and will be used to further characterize the genetic mechanisms underlying wp. Knowledge of the genetic basis of genetic sexing traits can be used to improve SIT in this species and expand it to other economically important Diptera.
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reconstructing a comprehensive transcriptome assembly of a white pupal translocated strain of the pest fruit fly Bactrocera cucurbitae
GigaScience, 2015Co-Authors: Sheina B Sim, Bernarda Calla, Brian Hall, Theodore Derego, Scott M GeibAbstract:Background: Bactrocera cucurbitae is a serious global agricultural pest. Basic genomic information is lacking for this species, and this would be useful to inform methods of control, damage mitigation, and eradication efforts. Here, we have sequenced, assembled, and annotated a comprehensive transcriptome for a mass-rearing sexing strain of this species. This forms a foundational genomic and transcriptomic resource that can be used to better understand the physiology and biochemistry of this insect as well as being a useful tool for population genetics. Findings: A transcriptome assembly was constructed containing 17,654 transcript isoforms derived from 10,425 unigenes. This transcriptome size is similar to reports from other Tephritid species and probably includes about 70-80% of the protein-coding genes in the genome. The dataset is publicly available in NCBI and GigaDB as a resource for researchers. Conclusions: Foundational knowledge on the protein-coding genes in B. cucurbitae will lead to improved resources for this species. Through comparison with a model system such as Drosophila as well as a growing number of related Tephritid transcriptomes, improved strategies can be developed to control this pest.
Sheina B Sim - One of the best experts on this subject based on the ideXlab platform.
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population genomics and comparisons of selective signatures in two invasions of melon fly Bactrocera cucurbitae diptera tephritidae
Biological Invasions, 2018Co-Authors: Luc Leblanc, Julian R Dupuis, Sheina B Sim, Michael San Jose, Aftab M Hoassain, Daniel Rubinoff, Scott M GeibAbstract:Population genetics is a powerful tool for invasion biology and pest management, and useful for a range of questions from tracing invasion pathways to informing management decisions with inference of population demographics. Genomics greatly increases the resolution of population-scale analyses, yet outside of model species with extensive genomic resources, few studies have used population genomics in invasion biology. We use genome-wide single nucleotide polymorphisms (SNPs) to investigate population genomic structure with samples from across the range of melon fly, Bactrocera cucurbitae (Coquillett, 1849), a highly polyphagous pest of commercial produce. We then make use of a chromosome-scale genome assembly and gene set to compare signatures of selection across the melon fly’s genome, both across our sampling as a whole and in the context of two independent, established introductions. Using multiple approaches, we find support for six genetic clusters across melon fly’s distribution. Some of these agree with previously identified genetic clusters using microsatellites, but consensus of clusters in mainland and oceanic southeast Asia is confounded by variable sampling between studies. We find few adaptive signatures across the genome, and virtually no unique signatures when comparing the two independent introductions, which suggests that similar management strategies are appropriate across melon fly’s range. This is the first use of genome-wide data to characterize population structure in tephritid fruit fly pests, and our SNP dataset provides a foundation for objective and cost-effective genotyping of previously collected melon fly specimens. Future research needs to focus on truly comprehensive sampling across melon fly’s range to overcome the historic variability of range-wide estimates of population structure for this pest.
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a chromosome scale assembly of the Bactrocera cucurbitae genome provides insight to the genetic basis of white pupae
G3: Genes Genomes Genetics, 2017Co-Authors: Sheina B Sim, Scott M GeibAbstract:Genetic sexing strains (GSS) used in sterile insect technique (SIT) programs are textbook examples of how classical Mendelian genetics can be directly implemented in the management of agricultural insect pests. Although the foundation of traditionally developed GSS are single locus, autosomal recessive traits, their genetic basis are largely unknown. With the advent of modern genomic techniques, the genetic basis of sexing traits in GSS can now be further investigated. This study is the first of its kind to integrate traditional genetic techniques with emerging genomics to characterize a GSS using the tephritid fruit fly pest Bactrocera cucurbitae as a model. These techniques include whole-genome sequencing, the development of a mapping population and linkage map, and quantitative trait analysis. The experiment designed to map the genetic sexing trait in B. cucurbitae, white pupae (wp), also enabled the generation of a chromosome-scale genome assembly by integrating the linkage map with the assembly. Quantitative trait loci analysis revealed SNP loci near position 42 MB on chromosome 3 to be tightly linked to wp. Gene annotation and synteny analysis show a near perfect relationship between chromosomes in B. cucurbitae and Muller elements A–E in Drosophila melanogaster. This chromosome-scale genome assembly is complete, has high contiguity, was generated using a minimal input DNA, and will be used to further characterize the genetic mechanisms underlying wp. Knowledge of the genetic basis of genetic sexing traits can be used to improve SIT in this species and expand it to other economically important Diptera.
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reconstructing a comprehensive transcriptome assembly of a white pupal translocated strain of the pest fruit fly Bactrocera cucurbitae
GigaScience, 2015Co-Authors: Sheina B Sim, Bernarda Calla, Brian Hall, Theodore Derego, Scott M GeibAbstract:Background: Bactrocera cucurbitae is a serious global agricultural pest. Basic genomic information is lacking for this species, and this would be useful to inform methods of control, damage mitigation, and eradication efforts. Here, we have sequenced, assembled, and annotated a comprehensive transcriptome for a mass-rearing sexing strain of this species. This forms a foundational genomic and transcriptomic resource that can be used to better understand the physiology and biochemistry of this insect as well as being a useful tool for population genetics. Findings: A transcriptome assembly was constructed containing 17,654 transcript isoforms derived from 10,425 unigenes. This transcriptome size is similar to reports from other Tephritid species and probably includes about 70-80% of the protein-coding genes in the genome. The dataset is publicly available in NCBI and GigaDB as a resource for researchers. Conclusions: Foundational knowledge on the protein-coding genes in B. cucurbitae will lead to improved resources for this species. Through comparison with a model system such as Drosophila as well as a growing number of related Tephritid transcriptomes, improved strategies can be developed to control this pest.
