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Marcelo L Larramendy - One of the best experts on this subject based on the ideXlab platform.
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chromosome determining system in Heteroptera
2016Co-Authors: Maria Jose Bressa, Alba G Papeschi, Liliana Maria Mola, Marcelo L LarramendyAbstract:The genus Dysdercus GueÂrin MeÂneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species from Dysdercus, including six species from the Old World and four species from the Neotropical Region have been cytogenetically analyzed. As is characteristic of Heteroptera, they possess holokinetic chromosomes and a prereductional type of meiosis. While the X1X20 sex chromosome system has been reported in all cytologically analyzed species of Dysdercus from the Old World, the system X0 has been found in all but one species from the New World, regardless of the number of autosomes in the complement. In the present study the male meiosis of D. albofasciatus Berg 1878 was studied in specimens from four different populations from Argentina. The diploid chromosome number was found to be 2n 10 neo-XY. The neo-X shows at each subterminal region a positively heteropycnotic and DAPI-bright segment which corresponds to the ancestral X-chromosome. The origin of this neo-XY system involved, most probably, a subterminal insertion of the ancestral X chromosome in an autosome, followed by a large inversion, which included part of the original X chromosome
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meiotic studies in Dysdercus guerin meneville 1831 heteroptera pyrrhocoridae ii evidence on variations of the diffuse stage between wild and laboratory inbred populations of Dysdercus chaquensis freiberg 1948
Hereditas, 2002Co-Authors: Maria Jose Bressa, Emiliano Fumagalli, Santiago Ituarte, Maria Victoria Frassa, Marcelo L LarramendyAbstract:Dysdercus Guerin Meneville, 1831 comprises insect species that are often serious pests of cotton both in the Old and New World, representing the only taxon from Pyrrhocoridae in the Neotropical Region. The genus is cytologically characterized by possession of holokinetic chromosomes and a prereductional type of meiosis. So far, only seven species from the Old World and five species from the Neotropical Region have been cytogenetically described. In the present report we compare the male meiosis from both natural and inbred populations of Dysdercus chaquensis Freiberg, 1948. Our results demonstrated that even though both populations share the same diploid chromosome number, the presence of a diffuse stage was found to be committed to the wild population of the species. Furthermore, the diffuse stage was found in a high frequency in all analysed wild specimens, indicating the long duration of this period among the regular meiosis of D. chaquensis. Taking into account that the diffuse stage is connected with an intense and long period of cellular growth, and with an important transcriptional activity, the absence of this stage in all the inbred specimens of D. chaquensis could be related with the lack of unfavourable physiological conditions due to the environmental uniformity along seven years of inbreeding.
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meiotic studies in Dysdercus guerin meneville 1831 heteroptera pyrrhocoridae i neo xy in Dysdercus albofasciatus berg 1878 a new sex chromosome determining system in heteroptera
Chromosome Research, 1999Co-Authors: Maria Jose Bressa, Alba G Papeschi, Liliana Maria Mola, Marcelo L LarramendyAbstract:The genus Dysdercus Guerin Meneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species from Dysdercus, including six species from the Old World and four species from the Neotropical Region have been cytogenetically analyzed. As is characteristic of Heteroptera, they possess holokinetic chromosomes and a prereductional type of meiosis. While the X1X20 sex chromosome system has been reported in all cytologically analyzed species of Dysdercus from the Old World, the system X0 has been found in all but one species from the New World, regardless of the number of autosomes in the complement. In the present study the male meiosis of D. Albofasciatus Berg 1878 was studied in specimens from four different populations from Argentina. The diploid chromosome number was found to be 2n = 10 + neo-XY. The neo-X shows at each subterminal region a positively heteropycnotic and DAPI-bright segment which corresponds to the ancestral X-chromosome. The origin of this neo-XY system involved, most probably, a subterminal insertion of the ancestral X chromosome in an autosome, followed by a large inversion, which included part of the original X chromosome.
Muhammad Mohsan - One of the best experts on this subject based on the ideXlab platform.
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Effects of selected synthetic insecticides on the total and differential populations of circulating haemocytes in adults of the red cotton stainer bug Dysdercus koenigii (Fabricius) (Hemiptera: Pyrrhocoridae)
Environmental Science and Pollution Research, 2018Co-Authors: Zahid Mahmood Sarwar, Mamuna Ijaz, Muhammad Altaf Sabri, Hasnain Yousaf, Muhammad MohsanAbstract:Red cotton bug, Dysdercus koenigii (Hemiptera: Pyrrhocoridae), has become the major insect pest of various crops, including cotton, and thereby reducing the yield qualitatively and quantitatively and synthetic insecticides belonging to different groups are the major control agents for such insect pests. A laboratory experiment was carried out to evaluate the effect of different conventional insecticides, i.e., imidacloprid, deltamethrin, lambda cyhalothrin, gamma cyhalothrin and cyfluthirn on haemocytes of D . koenigii . The individuals were exposed to insecticides separately and data was recorded after 30 and 60 min of the exposure. The findings of current study depicted chlorpyrifos to be more effective and significant alterations in total haemocyte counts and differential haemocyte counts were observed in the cyfluthirn treated D . koenigii . In addition to this, cell structure was also disrupted as an immune response. Similar studies would also be helpful to understand the defence mechanisms of insects against the xenobiotics which will help to device efficient management tools for D . koenigii .
Maria Jose Bressa - One of the best experts on this subject based on the ideXlab platform.
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chromosome determining system in Heteroptera
2016Co-Authors: Maria Jose Bressa, Alba G Papeschi, Liliana Maria Mola, Marcelo L LarramendyAbstract:The genus Dysdercus GueÂrin MeÂneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species from Dysdercus, including six species from the Old World and four species from the Neotropical Region have been cytogenetically analyzed. As is characteristic of Heteroptera, they possess holokinetic chromosomes and a prereductional type of meiosis. While the X1X20 sex chromosome system has been reported in all cytologically analyzed species of Dysdercus from the Old World, the system X0 has been found in all but one species from the New World, regardless of the number of autosomes in the complement. In the present study the male meiosis of D. albofasciatus Berg 1878 was studied in specimens from four different populations from Argentina. The diploid chromosome number was found to be 2n 10 neo-XY. The neo-X shows at each subterminal region a positively heteropycnotic and DAPI-bright segment which corresponds to the ancestral X-chromosome. The origin of this neo-XY system involved, most probably, a subterminal insertion of the ancestral X chromosome in an autosome, followed by a large inversion, which included part of the original X chromosome
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meiotic studies in Dysdercus guerin meneville 1831 heteroptera pyrrhocoridae ii evidence on variations of the diffuse stage between wild and laboratory inbred populations of Dysdercus chaquensis freiberg 1948
Hereditas, 2002Co-Authors: Maria Jose Bressa, Emiliano Fumagalli, Santiago Ituarte, Maria Victoria Frassa, Marcelo L LarramendyAbstract:Dysdercus Guerin Meneville, 1831 comprises insect species that are often serious pests of cotton both in the Old and New World, representing the only taxon from Pyrrhocoridae in the Neotropical Region. The genus is cytologically characterized by possession of holokinetic chromosomes and a prereductional type of meiosis. So far, only seven species from the Old World and five species from the Neotropical Region have been cytogenetically described. In the present report we compare the male meiosis from both natural and inbred populations of Dysdercus chaquensis Freiberg, 1948. Our results demonstrated that even though both populations share the same diploid chromosome number, the presence of a diffuse stage was found to be committed to the wild population of the species. Furthermore, the diffuse stage was found in a high frequency in all analysed wild specimens, indicating the long duration of this period among the regular meiosis of D. chaquensis. Taking into account that the diffuse stage is connected with an intense and long period of cellular growth, and with an important transcriptional activity, the absence of this stage in all the inbred specimens of D. chaquensis could be related with the lack of unfavourable physiological conditions due to the environmental uniformity along seven years of inbreeding.
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meiotic studies in Dysdercus guerin meneville 1831 heteroptera pyrrhocoridae i neo xy in Dysdercus albofasciatus berg 1878 a new sex chromosome determining system in heteroptera
Chromosome Research, 1999Co-Authors: Maria Jose Bressa, Alba G Papeschi, Liliana Maria Mola, Marcelo L LarramendyAbstract:The genus Dysdercus Guerin Meneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species from Dysdercus, including six species from the Old World and four species from the Neotropical Region have been cytogenetically analyzed. As is characteristic of Heteroptera, they possess holokinetic chromosomes and a prereductional type of meiosis. While the X1X20 sex chromosome system has been reported in all cytologically analyzed species of Dysdercus from the Old World, the system X0 has been found in all but one species from the New World, regardless of the number of autosomes in the complement. In the present study the male meiosis of D. Albofasciatus Berg 1878 was studied in specimens from four different populations from Argentina. The diploid chromosome number was found to be 2n = 10 + neo-XY. The neo-X shows at each subterminal region a positively heteropycnotic and DAPI-bright segment which corresponds to the ancestral X-chromosome. The origin of this neo-XY system involved, most probably, a subterminal insertion of the ancestral X chromosome in an autosome, followed by a large inversion, which included part of the original X chromosome.
Nogueira, Jeane Andréia Pedrosa - One of the best experts on this subject based on the ideXlab platform.
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Avaliação da bioatividade e estudo da composição química do óleo essencial das folhas de zanthoxylum tingoassuiba A. St. Hil
Niterói, 2017Co-Authors: Nogueira, Jeane Andréia PedrosaAbstract:Zanthoxylum tingoassuiba é uma espécie da família Rutaceae, popularmente conhecida como guando-do-mato, mamica-de-porca e limãozinho. Este trabalho descreve a análise da composição química do óleo essencial das folhas, sendo silvestreno identificado como constituinte majoritário através da análise por CG/EM. É a primeira vez que os constituintes muurola-4,5-trans-dieno e isodauceno são identificados no óleo essencial desta espécie. Para a atividade inseticida do óleo essencial desta espécie frente ao inseto Rhodnius prolixus, um dos vetores da doença de Chagas, foi observada alta taxa de mortalidade, mal formação e paralisia em ninfas de quinto estádio deste inseto. A atividade inseticida foi também avaliada frente aos fitófagos Dysdercus peruvianus e Oncopeltus fasciatus, insetos praga de lavoura. Em Dysdercus peruvianus o processo de metamorfose e período intermuda foram afetados e ocorreram deformações em alguns insetos tratados, além de mostrar uma alta taxa de mortalidade. Nos insetos Oncopeltus fasciatus, o tratamento com óleo puro e nas diluições de 500 mg/mL e 250mg/mL apresentou mortalidade de 100%. Na avaliação da atividade acaricida, ocorreu alteração na oviposição, diminuição da eclodibilidade dos ovos e 100% de mortalidade na concentração de 5%, além de mostrar que a eficácia do óleo essencial é dose dependente. Estes resultados sugerem que o óleo essencial das folhas de Z. tingoassuiba pode futuramente ser utilizado como ativo em formulações bioacaricidas, fazendo parte da terapêutica do carrapato do boi, um bioagente responsável por causar enormes danos a pecuária. Neste trabalho é relatado às atividades inseticida e carrapaticida para Zanthoxylum tingoassuiba, demonstrando que esta espécie possui um potencial biotecnológico a ser mais estudadoCoordenação de Aperfeiçoamento de Pessoal de Nível SuperiorZanthoxylum tingoassuiba is a species from the Rutaceae family, commonly known as “guando-do-mato”, “mamica - de - porca” e “limãozinho”. This work describes the analysis of the essential chemical composition of its leaves oil having identified the sylvestrene as a major component, through CGMS analysis. It is the first time that constituents muurola - trans - 4,5 - diene and isodaucene are identified in an essential oil from this species. It was observed, for insecticidal activity of the essential oil against the insect Rhodnius prolixus, one of the vectors of Chagas disease, a high mortality rate, malformation and paralysis in fifth instar nymphs. It was also evaluated against phytophagous Oncopeltus fasciatus and Dysdercus peruvianus, that are insects pests of crops. In Dysdercus peruvianus the process of metamorphosis and intermolt period were affected, some of the treated insects presented malformation and a high mortality rate. In Oncopeltus fasciatus, the treatment with pure oil and dilutions of 250.00mg/mL and 500.00mg/mL presented 100% mortality rate. In the acaricidal activity evaluation, changes occurred in oviposition, decreased hatchability of eggs and 100 % mortality at a concentration of 5 %. It also shows that the effectiveness of the essential oil is dose dependent. These results suggests that the essential oil from leaves Z. tingoassuiba can be used as actives in bioacaricidal formulations in the future, being part of the cattle tick therapeutics, a bioagent that causes huge damage to livestock. This work reports the insecticidal and acaricidal activities for Zanthoxylum tingoassuiba, showing that the species has a biotechnological potential for further studie
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Avaliação da bioatividade e estudo da composição química do óleo essencial das folhas de zanthoxylum tingoassuiba A. St. Hil
2017Co-Authors: Nogueira, Jeane Andréia PedrosaAbstract:Zanthoxylum tingoassuiba é uma espécie da família Rutaceae, popularmente conhecida como guando-do-mato, mamica-de-porca e limãozinho. Este trabalho descreve a análise da composição química do óleo essencial das folhas, sendo silvestreno identificado como constituinte majoritário através da análise por CG/EM. É a primeira vez que os constituintes muurola-4,5-trans-dieno e isodauceno são identificados no óleo essencial desta espécie. Para a atividade inseticida do óleo essencial desta espécie frente ao inseto Rhodnius prolixus, um dos vetores da doença de Chagas, foi observada alta taxa de mortalidade, mal formação e paralisia em ninfas de quinto estádio deste inseto. A atividade inseticida foi também avaliada frente aos fitófagos Dysdercus peruvianus e Oncopeltus fasciatus, insetos praga de lavoura. Em Dysdercus peruvianus o processo de metamorfose e período intermuda foram afetados e ocorreram deformações em alguns insetos tratados, além de mostrar uma alta taxa de mortalidade. Nos insetos Oncopeltus fasciatus, o tratamento com óleo puro e nas diluições de 500 mg/mL e 250mg/mL apresentou mortalidade de 100%. Na avaliação da atividade acaricida, ocorreu alteração na oviposição, diminuição da eclodibilidade dos ovos e 100% de mortalidade na concentração de 5%, além de mostrar que a eficácia do óleo essencial é dose dependente. Estes resultados sugerem que o óleo essencial das folhas de Z. tingoassuiba pode futuramente ser utilizado como ativo em formulações bioacaricidas, fazendo parte da terapêutica do carrapato do boi, um bioagente responsável por causar enormes danos a pecuária. Neste trabalho é relatado às atividades inseticida e carrapaticida para Zanthoxylum tingoassuiba, demonstrando que esta espécie possui um potencial biotecnológico a ser mais estudad
Zahid Mahmood Sarwar - One of the best experts on this subject based on the ideXlab platform.
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Effects of selected synthetic insecticides on the total and differential populations of circulating haemocytes in adults of the red cotton stainer bug Dysdercus koenigii (Fabricius) (Hemiptera: Pyrrhocoridae)
Environmental Science and Pollution Research, 2018Co-Authors: Zahid Mahmood Sarwar, Mamuna Ijaz, Muhammad Altaf Sabri, Hasnain Yousaf, Muhammad MohsanAbstract:Red cotton bug, Dysdercus koenigii (Hemiptera: Pyrrhocoridae), has become the major insect pest of various crops, including cotton, and thereby reducing the yield qualitatively and quantitatively and synthetic insecticides belonging to different groups are the major control agents for such insect pests. A laboratory experiment was carried out to evaluate the effect of different conventional insecticides, i.e., imidacloprid, deltamethrin, lambda cyhalothrin, gamma cyhalothrin and cyfluthirn on haemocytes of D . koenigii . The individuals were exposed to insecticides separately and data was recorded after 30 and 60 min of the exposure. The findings of current study depicted chlorpyrifos to be more effective and significant alterations in total haemocyte counts and differential haemocyte counts were observed in the cyfluthirn treated D . koenigii . In addition to this, cell structure was also disrupted as an immune response. Similar studies would also be helpful to understand the defence mechanisms of insects against the xenobiotics which will help to device efficient management tools for D . koenigii .