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Fernando E. Vega - One of the best experts on this subject based on the ideXlab platform.

Philippe Borsa - One of the best experts on this subject based on the ideXlab platform.

  • Single-stranded DNA conformation polymorphism at the Rdl locus in Hypothenemus hampei (Coleoptera: Scolytidae).
    Heredity, 1996
    Co-Authors: Philippe Borsa, Christine Coustau
    Abstract:

    Single-stranded DNA conformation polymorphism at the Rdl locus in Hypothenemus hampei (Coleoptera: Scolytidae)

  • Experimental evidence for pseudo-arrhenotoky in Hypothenemus hampei (Coleoptera: Scolytidae)
    Heredity, 1996
    Co-Authors: Philippe Borsa, Finn Kjellberg
    Abstract:

    Species breeding under local mate competition conditions have sex ratios biased towards females, a trait that is often associated with male haploidy (arrhenotoky). We used insecticide resistance as a genetic marker in Hypothenemus hampei , a local mate competing scolytid beetle that is cytologically diplo-diploid, for investigating the inheritance of nuclear genes. We confirmed that males express the resistance phenotype that they inherit from their mother, whatever their father. The segregation of resistance phenotypes in F_2 females significantly departed from the Mendelian model, and were in accordance with the arrhenotokous model, indicating that the parental genes were eliminated between F_1 and F_2. This finding (pseudo-arrhenotoky) constitutes a step towards an understanding of the mechanism by which diplo-diploidy evolves to arrhenotoky in local mate competing insects.

  • allozyme variation and an estimate of the inbreeding coefficient in the coffee berry borer Hypothenemus hampei coleoptera scolytidae
    Bulletin of Entomological Research, 1995
    Co-Authors: Philippe Borsa, Pierre D Gingerich
    Abstract:

    Seven presumed Mendelian enzyme loci (Est-2, Est-3, Gpi, Idh-I, Idh-2, Mdh-2 and Mpi) were characterized and tested for polymorphism in coffee berry borers, Hypothenemus hanzpei (Ferrari), sampled in Cote d'Ivoire, Mexico and New Caledonia. The average genetic diversity was H=0.080. Two loci, Mdh-2 and Mpi were poly- morphic, and thus usable as genetic markers. The population structure of H. hampei was analysed using Weir & Cockerham's estimators of Wright's F-statistics. A high degree of inbreeding (f=0.298) characterized the elementary geographic sampling unit, the coffee field. The estimate of gene flow between fields within a country was Nm =10.6 and that between countries was Nm =2. The population genetic structure in H. hampei could be related to its known population biological features and history. 21

D M Suckling - One of the best experts on this subject based on the ideXlab platform.

  • Cross resistance between insecticides in coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae) from New Caledonia.
    Bulletin of Entomological Research, 1994
    Co-Authors: Lucolivier Brun, Céline MARCILLAUD, V Gaudichon, D M Suckling
    Abstract:

    The responses of adult females of Hypothenemus hampei (Ferrari) from New Caledonia, which were either resistant or susceptible to endosulfan, were compared to a range of insecticides. High levels of cross resistance were present to organochlorines (aldrin, dieldrin and lindane). No cross resistance was evident to carbaryl or organophosphates (descending order of toxicity: fenitrothion > pirimiphos-methyl > chlorpyrifos > diazinon=malathion). Carbaryl, a carbamate, was the least toxic, and avermectin, a macrocyclic lactone, was the most toxic insecticide tested on H. hampei . No evidence of synergy from esterase (DEF) or microsomal oxidase (piperonyl butoxide) inhibitors was present.

  • Evaluation of a rapid bioassay for diagnosing endosulfan resistance in coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae)
    Tropical Pest Management, 1991
    Co-Authors: Lucolivier Brun, Céline MARCILLAUD, V Gaudichon, D M Suckling
    Abstract:

    Abstract The responses of adult female Hypothenemus hampei resistant and susceptible to endosulfan were compared using a vapour exposure method at five temperatures, from 22°C to 34°C, for up to 10 h. Susceptible insects showed a rapid increase in mortality 2–4 h after exposure to concentrations above 100 ppm. Resistant insects were largely unaffected at all combinations of temperature and exposure time. The LC50 of susceptibles declined with temperature, indicating a positive temperature coefficient. The method is recommended for early and reliable detection of endosulfan resistance after 6 h, at 25°C, with a concentration of 400 ppm.

Jean-yves Rasplus - One of the best experts on this subject based on the ideXlab platform.

  • Polymorphic microsatellite loci in the Coffee Berry Borer, Hypothenemus hampei (Coleoptera, Scolytidae)
    Molecular Ecology Notes, 2004
    Co-Authors: N. Gauthier, Jean-yves Rasplus
    Abstract:

    Microsatellite loci were isolated from the coffee berry borer, Hypothenemus hampei , which is regarded as the major pest in coffee cultures. Seven polymorphic loci were obtained from an enriched genomic library. A low to moderate genetic diversity was observed per locus, with an observed number of alleles ranging from two to five in the 39 unrelated individuals sampled from Ethiopia. A clear deficit of heterozygotes within the population (mean heterozygosities, H O = 0.10/ H E = 0.50) and an extreme inbreeding ( F IS , 0.70–1.00) were demonstrated. Cross-species amplifications showed that some of the markers could be useful in two closely related Hypothenemus species.

Maria Fatima Grossi-de-sa - One of the best experts on this subject based on the ideXlab platform.

  • Effect of a Bowman-Birk proteinase inhibitor from Phaseolus coccineus on Hypothenemus hampei gut proteinases in vitro.
    Journal of agricultural and food chemistry, 2007
    Co-Authors: Railene De Azevedo Pereira, Arnubio Valencia-jiménez, Cláudio P. Magalhães, Maura V. Prates, Jorge Alex Taquita Melo, Liziane M. Lima, Maurício P. Sales, Erich Y.t. Nakasu, Maria Cristina Mattar Da Silva, Maria Fatima Grossi-de-sa
    Abstract:

    The coffee berry borer, Hypothenemus hampei (Ferrari), is an important devastating coffee pest worldwide. Both trypsin and chymotrypsin enzyme activities from H. hampei larval midgut can be inactivated by proteinaceous enzyme-inhibitors. A serine proteinase inhibitor belonging to the Bowman-Birk class was purified from a wild accession of Phaseolus coccineus L. seeds. The inhibitor (PcBBI1) is a cysteine-rich protein that is heat-stable at alkaline pH. MALDI-TOF/MS analysis showed that PcBBI1 occurs in seeds as a monomer (8689 Da) or dimer (17,378 Da). Using in vitro inhibition assays, it was found that PcBBI1 has a high inhibitory activity against H. hampei trypsin-like enzymes, bovine pancreatic chymotrypsin, and trypsin. According to this, PcBBI1 could be a promising tool to make genetically modified coffee with resistance to coffee berry borer.