Compatibility between entomopathogenic fungi and biorational insecticides in toxicity against Ronderosia bergi under laboratory conditions

Our aim was to evaluate the efficacy of combinations between two biorational insecticides (luphenuron, methoxyfenozide), a new synthetic chemical pesticide (rynaxypyr), and three entomopathogenic fungi strains (Beauveria bassianaLPSc 1067, LPSc1082), and Metarhizium anisopliae (LPSc 907) in the biocontrol of the pest grasshopper Ronderosia bergi (Stål) under laboratory conditions. The insecticides were tested at three concentrations: the average concentration recommended for application in the field (100%) and 50% and finally 25% of that level. The fungal strains used were adjusted to 1×108, 1×106, and 1×104conidia ml-1. The combinations of those insecticides with B. bassiana (LPSc 1067, LPSc 1082) and M. anisopliae (LPSc 907) caused higher mortality to R. bergi nymphs than any of the individual agents used alone. The three insecticides tested did not affect the isolates of the two species of entomopathogenic fungi employed. In conclusion, the use of these biorational insecticides in an IPM program aimed at control of the grasshopper R. bergicould be of value

Pathogenic ability and saline stress tolerance of two Fusarium isolates from Odontesthes bonariensis eggs

Background Several fungal species represent a potential risk to embryos ofOdontesthes bonariensis(Cuvier and Valenciennes, 1835), a euryhaline freshwater fish that lives in the Pampean inland waters and has potential economic relevance. Aims To identify two fungi isolated fromO. bonariensiseggs exposed to saline conditions and to characterize their pathogenicity and tolerance to sodium chloride solutions. Methods The isolates were identified by morphological features, and a preliminar phylogenetic analysis using sequences of translation elongation factor 1-alpha (EF-1α) and calmodulin (CAM) was performed. Koch's postulates were tested to identify the causative agent of fungal infection. The influence of NaCl on the fungal growth was evaluated in in vitro assays. Results The isolates LPSC 1001 and 1002 were identified as representatives of the genusFusarium, and belonging to theFusarium incarnatum-Fusarium equisetispecies complex (FIESC) and theFusarium solanispecies complex (FSSC), respectively. Histological observations on eggs exposed in vitro to both isolates in infectivity assays confirmed the ability of the fungal isolates to penetrate to egg's chorionic membrane, leading to the death of embryos. Increasing NaCl concentration in the culture medium reduced the growth of the isolates LPSC 1001 and 1002, being completely inhibited at 160 and 120g/l NaCl respectively. Conclusions The isolates LPSC 1001 (FIESC) and 1002 (FSSC) were identified as fungal pathogens toO. bonariensiseggs. The use of NaCl solutions as antifungal treatment was not effective to control the infection with these strains.Antecedentes Diversas especies de hongos pueden representar un riesgo importante para los embriones deOdontesthes bonariensis(Cuvier & Valenciennes 1835), un pez de agua dulce eurihalino que vive en las aguas interiores pampeanas y tiene una relevancia económica potencial. Objetivos Identificar dos especies de hongos de huevos deO. bonariensisexpuestos a condiciones salinas y caracterizar su patogenicidad y tolerancia a las soluciones de cloruro de sodio. Métodos Se identificaron los aislamientos por sus características morfológicas, y se realizó un análisis filogenético preliminar utilizando secuencias de traslación del factor 1 alfa elongación (EF- 1α) y calmodulina (CAM). Se llevaron a cabo los postulados de Koch para identificar el agente causante de la infección fúngica. La influencia de NaCl sobre el crecimiento fúngico se evaluó en ensayos in vitro. Resultados Se identificaron los aislamientos LPSC 1001 y 1002 como representantes del géneroFusarium, y pertenecientes al complejo de especiesFusarium incarnatum-Fusarium equiseti(FIESC) y al complejo de especies deFusarium solani(FSSC), respectivamente. Las observaciones histológicas en los huevos expuestos in vitro a ambos aislamientos en los ensayos de infectividad confirmaron la capacidad de estos para penetrar en la membrana coriónica, lo que condujo a la muerte de los embriones. El aumento de la concentración de NaCl en el medio de cultivo redujo el crecimiento de los aislamientos LPSC 1001 y 1002, quedando completamente inhibidos a 160 y 120g/l de NaCl, respectivamente. Conclusiones Se identificaron los aislamientos LPSC 1001 (FIESC) y 1002 (FSSC) como hongos patógenos para los huevos deO. bonariensis; el uso de soluciones de NaCl como tratamiento antifúngico no resultó eficaz para el control de la infección con estas cepas.dia y mes probable de publicaió

Curriculum corruption? : On the place of subjects in secondary school curriculum making

The production of a W boson in association with a single charm quark is studied using 4.6 fb-1 of pp collision data at 1as = 7TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+-00.30 at Q2 = 1.9 GeV, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally the cross-section ratio \u3c3(W+ + c)/\u3c3(W- +c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s\u2013s quark asymmetry