Examinando por Materia "Paratrioza"

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  • Miniatura
    PublicaciónAcceso abierto
    Activity of two entomopathogenic fungi, molecularly identified, on bactericera cockerelli.
    (Universidad del Valle, 2017-06-30) Villegas Rodríguez, Fabiola; Díaz Gómez, Ovidio; Casas Flores, J. Sergio; Monreal Vargas, Clara Teresa; Tamayo Mejía, Fernando; Aguilar Medel, Sotero; Sociedad Colombiana de Entomología - Socolen; Universidad del Valle
    The potato psyllid Bactericera cockerelli affects solanaceous causes direct damage to crops in Mexico, as well as transmitting prokaryotic pathogens such as Candidatus Liberibacter solanacerum (psyllaurous). In the past, it has been controlled mainly using chemical products, while recent management strategies seek different strategies, including the use of enthomopathogenic fungi. The goal of this study was to evaluate the susceptibility of the potato psyllid to commercial and native Metarizhium anisopliae and Be. bassiana strains, and to determine the identity of these fungi through molecular techniques. Bioassays were done under laboratory conditions using the wild type (MA25) of anisopliae, the commercials strain (Metabich®, MA28), the Be. bassiana BB42 wild type strain, and the commercial strain Bassianil® BB09. Five different conidia concentrations were tested against third instar nymphs of Bactericera cockerelli, and their corresponding LC50 and LC95 were determined. The strains tested were pathogenic against the potato psyllid, with the highest virulence obtained using BB09 followed by BB42 and MA28. Using the highest concentrations of the strains, mortality varied between 90 and 100%, with the most virulent being BB09 with a LC50 of 2.99 x 104 conidia per ml, and the least virulent being MA25, with a LC50 of 6.34 x 105 conidia per ml. Previously, the Be. bassiana and M. anisopliae wild type strains were identified using conventional methods; this report confirms them through molecular techniques based on the cloning and sequencing of their rDNA 18S gene.
  • Miniatura
    PublicaciónAcceso abierto
    Morphometric of immatures and life tables of Bactericera cockerelli (Hemiptera: Triozidae) from populations of Northeastern Mexico.
    (Universidad del Valle, 2018-07-08) Cerna Chávez, Ernesto; Hernández Bautista, Omegar; Ochoa Fuentes, Yisa María; Landeros Flores, Jerónimo; Aguirre Uribe, Luis Alberto; Hernández Juárez, Agustín; Sociedad Colombiana de Entomología - Socolen; Universidad del Valle; Montoya Lerma, James
    Several parameters have been previously reported for Bactericera cockerelli biology that are influenced by the management, host and environmental conditions in which it develops. Therefore, the present study aimed to determine the population parameters of B. cockerelli from three field populations of northeastern Mexico and one laboratory population. Samples were collected in production areas of San Luis Potosi, Aguascalientes and Coahuila-Nuevo Leon, which were subsequently taken to a greenhouse and laboratory for data reading. The results show that the population from San Luis Potosi was the one that registered the highest number of eggs, with an average of 178.5 eggs at the time of revision, with the longest time required to complete the immature stage being 31.75 days; therefore, the longest time necessary for population doubling was an average of 11.07 days. The Aguascalientes population had the highest survival values, with 13 % of individuals reaching adulthood, as well as the parameters Σmx: 405, Ro: 10.53, rm: 0.089 y λ: 1.093. Finally, concerning fertility and pre-oviposition period, no significant differences between populations were recorded. The above demonstrates that populations exposed to selection pressure by pesticides change their population parameters.