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Thomas W Sappington - One of the best experts on this subject based on the ideXlab platform.
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population structure and genetic diversity of the Boll Weevil coleoptera curculionidae on gossypium in north america
Annals of The Entomological Society of America, 2012Co-Authors: Adam P Kuester, Thomas W Sappington, Kyung Seok Kim, Richard L Roehrdanz, Robert W Jones, Norman B Barr, Patti Senechal, John D NasonAbstract:ABSTRACT Although the Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a devastating pest in the United States and Mexico, its population structure and genetic diversity in Mexico on wild and cultivated cotton hosts (genus Gossypium) is poorly understood. Past studies using morphology, host use, and distribution records suggest that A. grandis grandis comprises three forms with host-associated characteristics: the southeastern form (from domesticated Gossypium hirsutum L., southeastern United States and northeastern Mexico), the thurberia form (from Gossypium thurberi Todaro, Arizona and northwestern Mexico), and the Mexican form (from multiple Gossypium species and other malvaceous plant genera in the remainder of Mexico and Central America). However, the phylogenetic relationships, host preferences, and distributions of these forms are not completely understood. An alternative hypothesis of an eastern and western form of the Boll Weevil is suggested by the suspected phylog...
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Molecular diagnostic for Boll Weevil (Coleoptera: Curculionidae) based on amplification of three species-specific microsatellites.
Journal of economic entomology, 2009Co-Authors: Kyung Seok Kim, Phillip G. Mulder, Zsofia Szendrei, Cesar Rodriguez-saona, Thomas W SappingtonAbstract:The Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a serious pest of cultivated cotton, Gossypium hirsutum L., in the Americas, and reinfestation of zones from which they have been eradicated is of perpetual concern. Extensive arrays of pheromone traps monitor for reintroductions, but occasionally the traps collect nontarget Weevils that can be misidentified by scouts. For example, the congeneric pepper Weevil, Anthonomus eugenii Cano, and other superficially similar Weevils are attracted to components of the Boll Weevil lure or trap color. Although morphologically distinguishable by trained personnel, the potential for misidentification is compounded when captured Weevils are dismembered or partially consumed by ants or ground beetles that sometimes feed on them in the traps. Because misidentification can have expensive consequences, a molecular diagnostic tool would be of great value to eradication managers. We demonstrate that a cocktail of three primer pairs in a single polymerase chain reaction (PCR) amplify species-specific microsatellites that unambiguously distinguish the Boll Weevil from three other Weevil species tested, including pepper Weevil; cranberry Weevil, Anthonomus eugenii musculus Say; and pecan Weevil, Curculio caryae Horn. However, it does not distinguish the Boll Weevil from the subspecific “thurberia” Weevil. A universal internal transcribed spacer primer pair included in the cocktail cross-amplifies DNA from all species, serving as a positive control. Furthermore, the diagnostic primers amplified the target microsatellites from various Boll Weevil adult body parts, indicating that the PCR technology using the primer cocktail is sensitive enough to positively identify a Boll Weevil even when the body is partly degraded.
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effects of photoperiod on Boll Weevil coleoptera curculionidae development survival and reproduction
Environmental Entomology, 2008Co-Authors: Shoil M. Greenberg, Thomas W Sappington, Tong-xian Liu, John J Adamczyk, Mamoudou SétamouAbstract:Effects of photoperiod on development, survival, feeding, and oviposition of Boll Weevils, Anthonomus grandis grandis Boheman, were assessed under five different photophases (24, 14, 12, 10, and 0 h) at a constant 27 degrees C temperature and 65% RH in the laboratory. Analyses of our results detected positive relationships between photoperiod and puncturing (mean numbers of oviposition and feeding punctures per day), and oviposition (oviposition punctures/oviposition+feeding punctures) activities, and the proportion of squares attacked by Boll Weevil females. When Boll Weevil females developed in light:darkness cycles, they produced a significantly higher percentage of eggs developing to adulthood than those developed in 24-h light or dark conditions. In long photoperiod (24:0 and 14:10 h), the number of female progeny was significantly higher and their development time was significantly shorter than those developed in short photoperiod (0:24 and 10:14 h). Lifetime oviposition was significantly highest at 12- and 14-h photophase, lowest at 0- and 10-h photophase, and intermediate at 24 h of light. Life table calculations indicated that Boll Weevil populations developed in a photoperiod of 14:10 and 12:12 (L:D) h will increase an average of two-fold each generation (Ro) compared with Boll Weevils developed in 24:0- and 10:14-h photoperiods and 15-fold compared with those at 0:24 h. Knowledge of the photoperiod-dependent population growth potential is critical for understanding population dynamics to better develop sampling protocols and timing insecticide applications.
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molecular genetic variation of Boll Weevil populations in north america estimated with microsatellites implications for patterns of dispersal
Genetica, 2006Co-Authors: Kyung Seok Kim, Thomas W SappingtonAbstract:The Boll Weevil (Anthonomus grandis Boheman) is an insect pest of cotton that underwent a welldocumented range expansion across the southeastern U.S. from Mexico beginning about 110 years ago. Eleven microsatellite loci were surveyed to infer the magnitude and pattern of genetic differentiation among Boll Weevil populations from 18 locations across eight U.S. states and northeast Mexico. Estimates of genetic diversity (allelic diversity and heterozygosity) were greater in Southern than Northern populations, and were greater in the west than the east among Northern populations. Boll Weevil populations were genetically structured as a whole across the geographic range sampled, with a global FST of 0.241. Southcentral populations exhibit classic isolation by distance, but evidence suggests that populations within the Eastern and Western regions have not yet reached genetic equilibrium. Gene flow appears to be relatively high among populations within the Eastern region. Population assignment data and estimates of gene flow indicate that migration between locations separated by <300 km is frequent. The database of microsatellite genotypes generated in this study now makes it possible, through population assignment techniques, to identify the most likely geographic source of a Boll Weevil reintroduced to an eradication zone, which will help action agencies decide the most appropriate mitigation response.
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Circadian rhythms of feeding, oviposition, and emergence of the Boll Weevil (Coleoptera: Curculionidae)
Insect Science, 2006Co-Authors: Shoil M. Greenberg, Thomas W Sappington, J. Scott Armstrong, Mamoudou Sétamou, Randy J. Coleman, Tong-xian LiuAbstract:Circadian rhythm of feeding, oviposition, and emergence of Boll Weevil adults were determined at five different photophases (24, 14, 12, 10, and 0 hours) and a constant 27 o C temperature, 65% RH in the laboratory. Squares from Petri dishes, where they were exposed to Boll Weevil females, were removed and examined for feeding and oviposition punctures every 4 hours during daylight (0700-1900 h) and every 12 h at night (1900-0700 h) over eight consecutive days. Cohorts of randomly selected egg-punctured squares were sampled from ovipositing females at 0700, 1100, 1500, and 1900 during 24 hours and under different photophase treatments, and maintained in Petri dishes at 27± 1 o C, 65% RH. Dishes were observed twice daily (1900 and 0700 h) for adults emerging at day or night. Circadian rhythm of oviposition was not affected by the length of the photophase. The Boll Weevil has round-the-clock circadian rhythm of oviposition, with a daytime preference. We observed that 82.4%-86.0% of the Boll Weevil eggs were deposited between 0700 and 1900 h, and 14.0%-17.6% between 1900 and 0700 h during a 24-h period. Feeding of Boll Weevil females in photoperiods 24: 0 h (complete light) and 0: 24 h (complete darkness) did not significantly change between 0700-1900 h versus 1900-0700 h, while the daily cycle of light and darkness in other photoperiods significantly increased the feeding punctures from 0700-1900 compared with 1900-0700 h. The circadian rhythm of emergence depended significantly on the time of oviposition and the length of the photophase. Investigation of Boll Weevil circadian rhythm provides a better understanding of Boll Weevil ecology and reveals potential weak links for improving control technologies targeting their reproductive strategies.
Marcio Alvesferreira - One of the best experts on this subject based on the ideXlab platform.
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transcriptome analysis of gossypium hirsutum flower buds infested by cotton Boll Weevil anthonomus grandis larvae
BMC Genomics, 2014Co-Authors: Sinara Artico, Leonardo L. P. Macedo, Maria Fatima Grossidesa, Marcelo Ribeiroalves, Osmundo B Oliveiraneto, Sylvia Rodrigues Da Silveira, Adriana Pinheiro Martinelli, Marcio AlvesferreiraAbstract:Background: Cotton is a major fibre crop grown worldwide that suffers extensive damage from chewing insects, including the cotton Boll Weevil larvae (Anthonomus grandis). Transcriptome analysis was performed to understand the molecular interactions between Gossypium hirsutum L. and cotton Boll Weevil larvae. The Illumina HiSeq 2000 platform was used to sequence the transcriptome of cotton flower buds infested with Boll Weevil larvae. Results: The analysis generated a total of 327,489,418 sequence reads that were aligned to the G. hirsutum reference transcriptome. The total number of expressed genes was over 21,697 per sample with an average length of 1,063 bp. The DEGseq analysis identified 443 differentially expressed genes (DEG) in cotton flower buds infected with Boll Weevil larvae. Among them, 402 (90.7%) were up-regulated, 41 (9.3%) were down-regulated and 432 (97.5%) were identified as orthologues of A. thaliana genes using Blastx. Mapman analysis of DEG indicated that many genes were involved in the biotic stress response spanning a range of functions, from a gene encoding a receptor-like kinase to genes involved in triggering defensive responses such as MAPK, transcription factors (WRKY and ERF) and signalling by ethylene (ET) and jasmonic acid (JA) hormones. Furthermore, the spatial expression pattern of 32 of the genes responsive to Boll Weevil larvae feeding was determined by “in situ” qPCR analysis from RNA isolated from two flower structures, the stamen and the carpel, by laser microdissection (LMD). Conclusion: A large number of cotton transcripts were significantly altered upon infestation by larvae. Among the changes in gene expression, we highlighted the transcription of receptors/sensors that recognise chitin or insect oral secretions; the altered regulation of transcripts encoding enzymes related to kinase cascades, transcription factors, Ca 2+ influxes, and reactive oxygen species; and the modulation of transcripts encoding enzymes from phytohormone signalling pathways. These data will aid in the selection of target genes to genetically engineer cotton to control the cotton Boll Weevil.
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transcriptome analysis of gossypium hirsutum flower buds infested by cotton Boll Weevil anthonomus grandis larvae
BMC Genomics, 2014Co-Authors: Sinara Artico, Maria Fatima Grossidesa, Marcelo Ribeiroalves, Osmundo B Oliveiraneto, Sylvia Rodrigues Da Silveira, Adriana Pinheiro Martinelli, Leonardo Lima Pepino De Macedo, Marcio AlvesferreiraAbstract:Cotton is a major fibre crop grown worldwide that suffers extensive damage from chewing insects, including the cotton Boll Weevil larvae (Anthonomus grandis). Transcriptome analysis was performed to understand the molecular interactions between Gossypium hirsutum L. and cotton Boll Weevil larvae. The Illumina HiSeq 2000 platform was used to sequence the transcriptome of cotton flower buds infested with Boll Weevil larvae. The analysis generated a total of 327,489,418 sequence reads that were aligned to the G. hirsutum reference transcriptome. The total number of expressed genes was over 21,697 per sample with an average length of 1,063 bp. The DEGseq analysis identified 443 differentially expressed genes (DEG) in cotton flower buds infected with Boll Weevil larvae. Among them, 402 (90.7%) were up-regulated, 41 (9.3%) were down-regulated and 432 (97.5%) were identified as orthologues of A. thaliana genes using Blastx. Mapman analysis of DEG indicated that many genes were involved in the biotic stress response spanning a range of functions, from a gene encoding a receptor-like kinase to genes involved in triggering defensive responses such as MAPK, transcription factors (WRKY and ERF) and signalling by ethylene (ET) and jasmonic acid (JA) hormones. Furthermore, the spatial expression pattern of 32 of the genes responsive to Boll Weevil larvae feeding was determined by “in situ” qPCR analysis from RNA isolated from two flower structures, the stamen and the carpel, by laser microdissection (LMD). A large number of cotton transcripts were significantly altered upon infestation by larvae. Among the changes in gene expression, we highlighted the transcription of receptors/sensors that recognise chitin or insect oral secretions; the altered regulation of transcripts encoding enzymes related to kinase cascades, transcription factors, Ca2+ influxes, and reactive oxygen species; and the modulation of transcripts encoding enzymes from phytohormone signalling pathways. These data will aid in the selection of target genes to genetically engineer cotton to control the cotton Boll Weevil.
Kyung Seok Kim - One of the best experts on this subject based on the ideXlab platform.
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population structure and genetic diversity of the Boll Weevil coleoptera curculionidae on gossypium in north america
Annals of The Entomological Society of America, 2012Co-Authors: Adam P Kuester, Thomas W Sappington, Kyung Seok Kim, Richard L Roehrdanz, Robert W Jones, Norman B Barr, Patti Senechal, John D NasonAbstract:ABSTRACT Although the Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a devastating pest in the United States and Mexico, its population structure and genetic diversity in Mexico on wild and cultivated cotton hosts (genus Gossypium) is poorly understood. Past studies using morphology, host use, and distribution records suggest that A. grandis grandis comprises three forms with host-associated characteristics: the southeastern form (from domesticated Gossypium hirsutum L., southeastern United States and northeastern Mexico), the thurberia form (from Gossypium thurberi Todaro, Arizona and northwestern Mexico), and the Mexican form (from multiple Gossypium species and other malvaceous plant genera in the remainder of Mexico and Central America). However, the phylogenetic relationships, host preferences, and distributions of these forms are not completely understood. An alternative hypothesis of an eastern and western form of the Boll Weevil is suggested by the suspected phylog...
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Molecular diagnostic for Boll Weevil (Coleoptera: Curculionidae) based on amplification of three species-specific microsatellites.
Journal of economic entomology, 2009Co-Authors: Kyung Seok Kim, Phillip G. Mulder, Zsofia Szendrei, Cesar Rodriguez-saona, Thomas W SappingtonAbstract:The Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a serious pest of cultivated cotton, Gossypium hirsutum L., in the Americas, and reinfestation of zones from which they have been eradicated is of perpetual concern. Extensive arrays of pheromone traps monitor for reintroductions, but occasionally the traps collect nontarget Weevils that can be misidentified by scouts. For example, the congeneric pepper Weevil, Anthonomus eugenii Cano, and other superficially similar Weevils are attracted to components of the Boll Weevil lure or trap color. Although morphologically distinguishable by trained personnel, the potential for misidentification is compounded when captured Weevils are dismembered or partially consumed by ants or ground beetles that sometimes feed on them in the traps. Because misidentification can have expensive consequences, a molecular diagnostic tool would be of great value to eradication managers. We demonstrate that a cocktail of three primer pairs in a single polymerase chain reaction (PCR) amplify species-specific microsatellites that unambiguously distinguish the Boll Weevil from three other Weevil species tested, including pepper Weevil; cranberry Weevil, Anthonomus eugenii musculus Say; and pecan Weevil, Curculio caryae Horn. However, it does not distinguish the Boll Weevil from the subspecific “thurberia” Weevil. A universal internal transcribed spacer primer pair included in the cocktail cross-amplifies DNA from all species, serving as a positive control. Furthermore, the diagnostic primers amplified the target microsatellites from various Boll Weevil adult body parts, indicating that the PCR technology using the primer cocktail is sensitive enough to positively identify a Boll Weevil even when the body is partly degraded.
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molecular genetic variation of Boll Weevil populations in north america estimated with microsatellites implications for patterns of dispersal
Genetica, 2006Co-Authors: Kyung Seok Kim, Thomas W SappingtonAbstract:The Boll Weevil (Anthonomus grandis Boheman) is an insect pest of cotton that underwent a welldocumented range expansion across the southeastern U.S. from Mexico beginning about 110 years ago. Eleven microsatellite loci were surveyed to infer the magnitude and pattern of genetic differentiation among Boll Weevil populations from 18 locations across eight U.S. states and northeast Mexico. Estimates of genetic diversity (allelic diversity and heterozygosity) were greater in Southern than Northern populations, and were greater in the west than the east among Northern populations. Boll Weevil populations were genetically structured as a whole across the geographic range sampled, with a global FST of 0.241. Southcentral populations exhibit classic isolation by distance, but evidence suggests that populations within the Eastern and Western regions have not yet reached genetic equilibrium. Gene flow appears to be relatively high among populations within the Eastern region. Population assignment data and estimates of gene flow indicate that migration between locations separated by <300 km is frequent. The database of microsatellite genotypes generated in this study now makes it possible, through population assignment techniques, to identify the most likely geographic source of a Boll Weevil reintroduced to an eradication zone, which will help action agencies decide the most appropriate mitigation response.
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genetic structuring of Boll Weevil populations in the us based on rapd markers
Insect Molecular Biology, 2004Co-Authors: Kyung Seok Kim, Thomas W SappingtonAbstract:Abstract Randomly amplified polymorphic DNA (RAPD) analysis was performed to infer the magnitude and pattern of genetic differentiation among Boll Weevil populations from eighteen locations across eight US states and north-east Mexico. Sixty-seven reproducible bands from six random primers were analysed for genetic variation within and between Weevil populations. Genetic and geographical distances among all populations were positively correlated, reflecting a pattern of isolation by distance within a larger metapopulation. Gene flow between south-central, western and eastern regions is limited, but migration between locations within regions appears to be relatively frequent up to distances of approximately 300-400 km. However, estimates of effective migration were much lower than those estimated from mtDNA-RFLP data reported previously.
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Boll Weevil anthonomus grandis boheman coleoptera curculionidae dispersal in the southern united states evidence from mitochondrial dna variation
Environmental Entomology, 2004Co-Authors: Kyung Seok Kim, Thomas W SappingtonAbstract:An understanding of Boll Weevil (Anthonomus grandis Boheman) dispersal behavior is essential to characterizing and responding to the threat of migration into eradication zones. Genetic variation in Boll Weevil mitochondrial DNA (mtDNA) was sampled and analyzed to make inferences on the magnitude and geographic pattern of genetic differentiation among Weevil populations from 20 locations across eight U.S. states and northeast Mexico. Polymerase chain reaction (PCR)-restriction fragment length polymorphisms (RFLPs) analysis was conducted on a 12.4-kb amplicon of mtDNA from each of 419 individuals. A total of 28 distinct mtDNA haplotypes, 17 of which were unique to single locations, were identified from restriction reactions of 10 informative endonucleases. Haplotype and nucleotide diversity was generally greater in southern than northern populations and was greater in the east than the west among northern populations. Genetic differentiation between eastern and western populations was pronounced, and phylogenetic analyses revealed two major clades corresponding to these regions. These results are consistent with historical Boll Weevil range expansion into the southeastern United States from Mexico and a secondary colonization of the High Plains. Evidence suggests that gene flow is limited between eastern and western populations but is relatively high among populations within the eastern region. In addition, estimates of gene flow indicate that migration between locations separated by <300 km is frequent.
Maria Fatima Grossidesa - One of the best experts on this subject based on the ideXlab platform.
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transcriptome analysis of gossypium hirsutum flower buds infested by cotton Boll Weevil anthonomus grandis larvae
BMC Genomics, 2014Co-Authors: Sinara Artico, Maria Fatima Grossidesa, Marcelo Ribeiroalves, Osmundo B Oliveiraneto, Sylvia Rodrigues Da Silveira, Adriana Pinheiro Martinelli, Leonardo Lima Pepino De Macedo, Marcio AlvesferreiraAbstract:Cotton is a major fibre crop grown worldwide that suffers extensive damage from chewing insects, including the cotton Boll Weevil larvae (Anthonomus grandis). Transcriptome analysis was performed to understand the molecular interactions between Gossypium hirsutum L. and cotton Boll Weevil larvae. The Illumina HiSeq 2000 platform was used to sequence the transcriptome of cotton flower buds infested with Boll Weevil larvae. The analysis generated a total of 327,489,418 sequence reads that were aligned to the G. hirsutum reference transcriptome. The total number of expressed genes was over 21,697 per sample with an average length of 1,063 bp. The DEGseq analysis identified 443 differentially expressed genes (DEG) in cotton flower buds infected with Boll Weevil larvae. Among them, 402 (90.7%) were up-regulated, 41 (9.3%) were down-regulated and 432 (97.5%) were identified as orthologues of A. thaliana genes using Blastx. Mapman analysis of DEG indicated that many genes were involved in the biotic stress response spanning a range of functions, from a gene encoding a receptor-like kinase to genes involved in triggering defensive responses such as MAPK, transcription factors (WRKY and ERF) and signalling by ethylene (ET) and jasmonic acid (JA) hormones. Furthermore, the spatial expression pattern of 32 of the genes responsive to Boll Weevil larvae feeding was determined by “in situ” qPCR analysis from RNA isolated from two flower structures, the stamen and the carpel, by laser microdissection (LMD). A large number of cotton transcripts were significantly altered upon infestation by larvae. Among the changes in gene expression, we highlighted the transcription of receptors/sensors that recognise chitin or insect oral secretions; the altered regulation of transcripts encoding enzymes related to kinase cascades, transcription factors, Ca2+ influxes, and reactive oxygen species; and the modulation of transcripts encoding enzymes from phytohormone signalling pathways. These data will aid in the selection of target genes to genetically engineer cotton to control the cotton Boll Weevil.
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transcriptome analysis of gossypium hirsutum flower buds infested by cotton Boll Weevil anthonomus grandis larvae
BMC Genomics, 2014Co-Authors: Sinara Artico, Leonardo L. P. Macedo, Maria Fatima Grossidesa, Marcelo Ribeiroalves, Osmundo B Oliveiraneto, Sylvia Rodrigues Da Silveira, Adriana Pinheiro Martinelli, Marcio AlvesferreiraAbstract:Background: Cotton is a major fibre crop grown worldwide that suffers extensive damage from chewing insects, including the cotton Boll Weevil larvae (Anthonomus grandis). Transcriptome analysis was performed to understand the molecular interactions between Gossypium hirsutum L. and cotton Boll Weevil larvae. The Illumina HiSeq 2000 platform was used to sequence the transcriptome of cotton flower buds infested with Boll Weevil larvae. Results: The analysis generated a total of 327,489,418 sequence reads that were aligned to the G. hirsutum reference transcriptome. The total number of expressed genes was over 21,697 per sample with an average length of 1,063 bp. The DEGseq analysis identified 443 differentially expressed genes (DEG) in cotton flower buds infected with Boll Weevil larvae. Among them, 402 (90.7%) were up-regulated, 41 (9.3%) were down-regulated and 432 (97.5%) were identified as orthologues of A. thaliana genes using Blastx. Mapman analysis of DEG indicated that many genes were involved in the biotic stress response spanning a range of functions, from a gene encoding a receptor-like kinase to genes involved in triggering defensive responses such as MAPK, transcription factors (WRKY and ERF) and signalling by ethylene (ET) and jasmonic acid (JA) hormones. Furthermore, the spatial expression pattern of 32 of the genes responsive to Boll Weevil larvae feeding was determined by “in situ” qPCR analysis from RNA isolated from two flower structures, the stamen and the carpel, by laser microdissection (LMD). Conclusion: A large number of cotton transcripts were significantly altered upon infestation by larvae. Among the changes in gene expression, we highlighted the transcription of receptors/sensors that recognise chitin or insect oral secretions; the altered regulation of transcripts encoding enzymes related to kinase cascades, transcription factors, Ca 2+ influxes, and reactive oxygen species; and the modulation of transcripts encoding enzymes from phytohormone signalling pathways. These data will aid in the selection of target genes to genetically engineer cotton to control the cotton Boll Weevil.
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employing in vitro directed molecular evolution for the selection of α amylase variant inhibitors with activity toward cotton Boll Weevil enzyme
Journal of Biotechnology, 2013Co-Authors: Maria Cristina Mattar Da Silva, Daniel J. Rigden, Erika V.s. Albuquerque, Rafael Perseghini Del Sarto, Wagner Alexandre Lucena, F R Teixeira, Caroline De Andrade Bezerra, Maria Fatima GrossidesaAbstract:Numerous species of insect pests attack cotton plants, out of which the cotton Boll Weevil (Anthonomus grandis) is the main insect in Brazil and must be controlled to avert large economic losses. Like other insect pests, A. grandis secretes a high level of α-amylases in the midgut lumen, which are required for digestion of carbohydrates. Thus, α-amylase inhibitors (α-AIs) represent a powerful tool to apply in the control of insect pests. Here, we applied DNA shuffling and phage display techniques and obtained a combinatorial library containing 108α-AI variant forms. From this library, variants were selected exhibiting in vitro affinity for cotton Boll Weevil α-amylases. Twenty-six variant sequences were cloned into plant expression vectors and expressed in Arabidopsis thaliana. Transformed plant extracts were assayed in vitro to select specific and potent α-amylase inhibitors against Boll Weevil amylases. While the wild type inhibitors, used to create the shuffled library, did not inhibit the A. grandis α-amylases, three α-AI mutants, named α-AIC3, α-AIA11 and α-AIG4 revealed high inhibitory activities against A. grandis α-amylases in an in vitro assay. In summary, data reported here shown the potential biotechnology of new α-AI variant genes for cotton Boll Weevil control.
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toxicity to cotton Boll Weevil anthonomus grandis of a trypsin inhibitor from chickpea seeds
Comparative Biochemistry and Physiology B, 2005Co-Authors: Angelica De P G Gomes, Rose Gomes Monnerat, Simoni Campos Dias, Carlos Bloch, Francislete R Melo, Maria Fatima Grossidesa, Jose R Furtado, Octavio L FrancoAbstract:Cotton (Gossypium hirsutum L.) is an important agricultural commodity, which is attacked by several pests such as the cotton Boll Weevil Anthonomus grandis. Adult A. grandis feed on fruits and leaf petioles, reducing drastically the crop production. The predominance of Boll Weevil digestive serine proteinases has motivated inhibitor screenings in order to discover new ones with the capability to reduce the digestion process. The present study describes a novel proteinase inhibitor from chickpea seeds (Cicer arietinum L.) and its effects against A. grandis. This inhibitor, named CaTI, was purified by using affinity Red-Sepharose Cl-6B chromatography, followed by reversed-phase HPLC (Vydac C18-TP). SDS-PAGE and MALDI-TOF analyses, showed a unique monomeric protein with a mass of 12,877 Da. Purified CaTI showed significant inhibitory activity against larval cotton Boll Weevil serine proteinases (78%) and against bovine pancreatic trypsin (73%), when analyzed by fluorimetric assays. Although the molecular mass of CaTI corresponded to α-amylase/trypsin bifunctional inhibitors masses, no inhibitory activity against insect and mammalian α-amylases was observed. In order to observe CaTI in vivo effects, an inhibitor rich fraction was added to an artificial diet at different concentrations. At 1.5% (w/w), CaTI caused severe development delay, several deformities and a mortality rate of approximately 45%. These results suggested that CaTI could be useful in the production of transgenic cotton plants with enhanced resistance toward cotton Boll Weevil.
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effects of soybean kunitz trypsin inhibitor on the cotton Boll Weevil a nthonomus grandis
Phytochemistry, 2004Co-Authors: Rose Gomes Monnerat, Octavio L Franco, Simoni Campos Dias, Claudio P Magalhaes, Ana C S Monteiro, Carlos Bloch, Francislete R Melo, O B Oliveiraneto, Maria Fatima GrossidesaAbstract:The cotton Boll Weevil, Anthonomus grandis, is an economically important pest of cotton in tropical and subtropical areas of several countries in the Americas, causing severe losses due to their damage in cotton floral buds. Enzymatic assays using gut extracts from larval and adult Boll Weevil have demonstrated the presence of digestive serine proteinase-like activities. Furthermore, in vitro assays showed that soybean Kunitz trypsin inhibitor (SKTI) was able to inhibit these enzymes. Previously, in vivo effects of black-eyed pea trypsin chymotrypsin inhibitor (BTCI) have been demonstrated towards the Boll Weevil pest. Here, when neonate larvae were reared on an artificial diet containing SKTI at three different concentrations, a reduction of larval weight of up to 64% was observed for highest SKTI concentration 500 μM. The presence of SKTI caused an increase in mortality and severe deformities of larvae, pupae and adult insects. This work therefore represents the first observation of a Kunitz trypsin inhibitor active in vivo and in vitro against A. grandis. Bioassays suggested that SKTI could be used as a tool in engineering crop plants, which might exhibit increased resistance against cotton Boll Weevil.
Charles P.-c. Suh - One of the best experts on this subject based on the ideXlab platform.
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population genomics and phylogeography of the Boll Weevil anthonomus grandis boheman coleoptera curculionidae in the united states northern mexico and argentina
Evolutionary Applications, 2021Co-Authors: Tyler J Raszick, Charles P.-c. Suh, Lindsey C Perkin, Ashley E Tessnow, Raul Ruizarce, Theodore N Boratynski, Michael C Dickens, Marcelo R Falco, Spencer J Johnston, Gregory A SwordAbstract:The Boll Weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), is an important pest of commercial cotton across the Americas. In the United States, eradication of this species is complicated by re-infestations of areas where eradication has been previously successful and by the existence of morphologically similar variants that can confound identification efforts. To date, no study has applied a high-throughput sequencing approach to better understand the population genetic structure of the Boll Weevil. Furthermore, only a single study has investigated genetic relationships between populations in North and South America. We used double digest restriction site-associated DNA sequencing (ddRADseq) to resolve the population genomic structure of the Boll Weevil in the southern United States, northern Mexico, and Argentina. Additionally, we assembled the first complete mitochondrial genome for this species and generated a preliminary whole genome assembly, both of which were used to improve the identification of informative loci. Downstream analyses revealed two main lineages-one consisting of populations found geographically west of the Sierra Madre Occidental mountain range and the second consisting of populations found to the east-were revealed, and both were sub-structured. Population geographic structure was consistent with the isolation by distance model, indicating that geogrpahic distance is likely a primary mechanism driving divergence in this species. Boll Weevil populations from Argentina were found to be more closely related to the eastern lineage, suggesting a recent colonization of South America by the eastern lineage, but additional sampling across Mexico, Central America and South America is needed to further clarify their origin. Finally, we uncovered an instance of population turnover or replacement, highlighting the temporal instability of population structure.
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population genomics and phylogeography of the Boll Weevil anthonomus grandis boheman coleoptera curculionidae in the united states northern mexico and argentina
Authorea Preprints, 2020Co-Authors: Tyler J Raszick, Charles P.-c. Suh, C Dickens, Lindsey C Perkin, Ashley E Tessnow, Raul Ruizarce, Theodore N Boratynski, Marcelo Falco, Spencer Johnston, Gregory A SwordAbstract:Despite the success of the United States (US) Boll Weevil Eradication Program, the Boll Weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), remains a threat to cotton production in the southern US and is arguably the most important cotton pest in Central and South America. Management of this species is complicated by the existence of morphologically similar variants and re-infestations of areas where eradication had been successful. To date, no study has applied a high-throughput sequencing approach to better understand the population genetic structure of the Boll Weevil. Furthermore, only a single study has investigated genetic relationships between populations in North and South America. Here, we used double digest restriction site-associated DNA sequencing (ddRADseq) to resolve the population genomic structure of the Boll Weevil in the southern US, northern Mexico, and Argentina, test the two-form and three-form hypotheses of Boll Weevil variation in North America using a phylogeographic approach, and determine the relationship of the South American populations to the North. Our results supported the two-form hypothesis of Boll Weevil variation in North America wherein there are two major genetic lineages – one consisting of populations found geographically west of the Sierra Madre Occidental mountain range and the second consisting of populations found to the east – both are highly sub-structured across space and time. Boll Weevil populations from Argentina were more closely related to the eastern lineage, suggesting a range expansion by the eastern lineage, but additional sampling across Central and South America is needed to determine a probable origin.
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diapause response of the Boll Weevil coleoptera curculionidae to selected diets
Journal of Entomological Science, 2019Co-Authors: D W Spurgeon, Charles P.-c. Suh, J F EsquivelAbstract:The Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), once the dominant pest of cotton (Gossypium spp.) in the United States, is now the most serious pest of South American cotton. Despite eradication efforts in the United States, intractable populations in southern Texas and northern Mexico remain a threat to adjoining regions. A key to eliminating this pest from the subtropics may lie in better understanding mechanisms facilitating survival through the non–cotton season. We examined the diapause response to diet regimes by evaluating the influences of food type (square, Boll), size, and replacement interval, under photoperiod (13:11 [L:D] h) and temperature conditions (29.4°C) considered to suppress diapause. Female Weevils exhibited diapause characters earlier than did males on all diets, and physiological status was not reliably evaluated until adults were 9 d old. When squares fed to groups of Weevils were replaced thrice weekly, most Weevils responded with symptoms of starvation instead of diapause. In other feeding regimes, incidence of diapause increased with increasing food development, which may reflect the Weevil perception of host maturity. These results are consistent with accounts of seasonality of diapause and host utilization in the subtropics and tropics, as well as accounts of lateseason Weevil ecology in temperate regions prior to the widespread adoption of mechanized harvest and determinant cotton cultivars. These findings, combined with earlier demonstrations of extended host-free longevity and lack of a photoperiod response, identify food characteristics as important determinants of Boll Weevil reproductive diapause irrespective of other environmental cues.
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Termination of Diapause in the Boll Weevil (Coleoptera: Curculionidae).
Journal of economic entomology, 2018Co-Authors: Dale W. Spurgeon, Charles P.-c. SuhAbstract:The Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a major pest of cotton (Gossypium spp. (Malvales: Malvaceae)) in Mexico, South America, and South Texas in the United States. The ability of the Boll Weevil to survive extended cotton-free periods has been key to its persistence as a pest despite intensive control efforts. However, the mechanism facilitating survival has been subject to debate. Whereas adult diapause has long been considered the principal survival mechanism, some authors have characterized the dormancy as a quiescence. We induced dormancy in the Weevil and examined whether food type, enforced starvation, or induced flight influenced termination of the dormancy. Providing dormant adult Weevils a diet favoring reproduction for 7-14 d prompted a modest termination response in female Weevils and virtually no response in males. Some Weevils starved ≥21 d resumed reproduction after exposure to a favorable diet, but most Weevils remained dormant. Induced flight followed by exposure to a favorable diet prompted >50% of the Weevils to terminate the dormancy. Patterns of feeding and oviposition were also useful in interpreting the termination response. These results indicate that the dormancy exhibited by the Weevil is a diapause of variable intensity rather than a quiescence. A conceptual model recognizing population heterogeneity in diapause induction and intensity is consistent with reports of host-free survival and accommodates perceived differences in Boll Weevil ecology among temperate, subtropical, and tropical regions. This model provides a framework that will be valuable to research, management, and eradication efforts in the tropics and subtropics.
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diapause response of the Boll Weevil coleoptera curculionidae to feeding period duration and cotton square size
Journal of Insect Science, 2018Co-Authors: D W Spurgeon, Charles P.-c. Suh, J F EsquivelAbstract:Distribution of the Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), in the United States has been greatly reduced by eradication efforts. Still, it remains a key pest of cotton (Gossypium spp., [Malvales: Malvaceae]) in the New World, and has proven difficult to eliminate from Mexico and from southern Texas. In those regions, improved knowledge of Boll Weevil overwintering ecology may benefit efforts by eradication and management programs. Adult diapause in the Boll Weevil is well documented, but influences of the feeding period duration between adult eclosion and assessment of diapause remain unstudied. We examined diapause incidence and associated survival for Weevils fed for 7, 14, or 21 d after adult eclosion. Diapause incidence of females was less influenced by feeding duration compared with males. For males, highest diapause incidence occurred after 14 d of feeding compared with 7 or 21 d. Host-free survival tended to be higher after 14 d of feeding compared with 7 or 21 d, although many Weevils were long-lived (≥80 d) after each feeding period duration. Males exhibited higher survival compared with females, and survival was higher for Weevils fed large flower buds (squares) compared with smaller squares. Survival was most influenced by temperature; longevity increased with decreasing temperature except at the lowest temperature (12.8°C). These results suggest an optimal feeding period for induction of diapause and maximized host-free longevity. These findings may permit improved timing of late-season insecticide treatments aimed at reducing overwintering populations, and thereby improve effectiveness of eradication and management programs.