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Ophiocordyceps dominicanus Poinar & Vega sp. nov. in Dominican amber and Polycephalomyces baltica Poinar & Vega sp. nov. (Hypocreales: Ophiocordycipitaceae) in Baltic amber are described as entomopathogenic fungi of bark lice (Psocoptera). The specimens possess several features unknown in extant synnematous entomopathogenic fungi such as a tubular dark synnema with a straight, pointed tip bearing spores over the entire surface in O. dominicanus, and a globular yellowish synnema developing on the tip of the host's antenna in P. baltica. These are the only known fossil entomopathogenic fungi of bark lice, making them unique not only for their characters but also in respect to their selection of developmental sites on their bark lice hosts.

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Abstract Background: Tarsus hyperflexion alters locomotion biomechanics in horses. This alteration is of frequent presentation in the Colombian creole horse (CCH). Objective: To determine the echographic alterations of lateral digital extensor (LDE) muscle, tendon, and synovial sheath in CCH with clinical signs of tarsus hyperflexion. Methods: Thirty horses were divided into two groups: 15 healthy horses with no history of locomotion defects (Group 1; control), and 15 horses with clinical signs of tarsus hyperflexion (Group 2). A cross-sectional and a longitudinal echocardiographic examination of the LDE muscle and tendon was performed in all horses, and a histopathological study was performed only to Group 2. Results: 86.7% of the horses showed echographic alterations, with 53.4% showing signs of adhesions in the LDE muscle and tendon in the lateral surface of the hock, where it crosses the tarsus. 33.3% presented increased tendon synovial sheath fluid. 13.3% showed no echographic alterations and 53.3% presented histopathological alterations. Conclusion: These findings may be related to the presentation of tarsus hyperflexion that could characterize the classic stringhalt in CCH.

Resumen Antecedentes: la hiperflexión del tarso (corvejon) altera la biomecánica del desplazamiento en los caballos. Esta alteración es de presentación frecuente en el caballo criollo colombiano (CCC). Objetivo: determinar las alteraciones ecográficas del músculo extensor digital lateral (EDL), tendón y vaina sinovial en CCC con signos clínicos de hiperflexión del corvejón. Métodos: treinta caballos fueron divididos en dos grupos: 15 equinos clínicamente sanos, sin historia de defectos de locomoción (Grupo 1; considerado como control), y 15 equinos con signos clínicos de hiperflexión del corvejón (Grupo 2). Se realizó un examen ecográfico transversal y longitudinal del músculo y tendón del EDL en todos los animales, y un estudio histopatológico solo al Grupo 2. Resultados: el 86,7% de los caballos mostraron alteraciones ecográficas. El 53,4% mostró signos de adherencias en el músculo y tendón del EDL, en donde la superficie lateral del corvejón se cruza con el tarso. El 33,3% presentó un aumento en el líquido de la vaina sinovial del tendón. El 13,3% no presentó ninguna alteración ecográfica, y el 53,3% mostró alteraciones histopatológicas. Conclusión: estos hallazgos podrían estar relacionados con la presentación de hiperflexión del tarso que puede caracterizar el arpeo clásico en el CCC.

Resumo Antecedentes: a hiperflexão do tarso altera a biomecânica da locomoção dos cavalos. Esta alteração é de frequente apresentação no cavalo crioulo colombiano (CCC). Objetivo: determinar as alterações no ultrassom do músculo extensor digital lateral (EDL), o tendão e a bainha sinovial em CCC com sinais clínicos de hiperflexão do jarrete. Métodos: trinta cavalos foram divididos em dois grupos: 15 cavalos clinicamente saudáveis sem histórico de alterações em locomoção (Grupo 1; considerada como controlo), e 15 cavalos com sinais clínicos de hiperflexão do jarrete (Grupo 2). Se realizaram avaliações ultrassonográficas transversais e longitudinais do músculo e do tendão do EDL na totalidade dos animais e estudo histopatológico só ao Grupo 2. Resultados: o 86.7% dos equinos mostraram alterações no ultrassom, o 53.4% mostrou aderências no tendão do EDL na proximidade onde cruza a superfície lateral do jarrete, o 33.3% apresentou aumento do líquido da bainha sinovial do tendão, o 13.3% não apresentou nenhuma alteração ultrassonográfica e o 53.3% mostrou alterações histopatológicas. Conclusão: esses achados podem estar relacionados à apresentação da hiperflexão do tarso que poderiam caracterizar o arpejamento clássico no CCC.

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The common bean is the most important food legume in the world. We examined the potential of the fungal entomopathogens Beauveria bassiana and Metarhizium anisopliae applied as seed treatments for their endophytic establishment in the common bean. Endophytic colonization in sterile sand:peat averaged ca. 40% higher for fungus treatments and ca. six times higher for volunteer fungi (other fungal endophytes naturally occurring in our samples), relative to sterile vermiculite. Colonization by B. bassiana and M. anisopliae was least variable in sterile vermiculite and most variable in sterile soil:sand:peat. The impact of soil sterilization on endophytic colonization was assessed in a separate experiment using six different field-collected soils. Soil sterilization was the variable with the largest impact on colonization (70.8% of its total variance), while the fungal isolate used to inoculate seeds explained 8.4% of the variance. Under natural microbial soil conditions experienced by common bean farmers, seed inoculations with B. bassiana and M. anisopliae are unlikely to yield predictable levels of endophytic colonization.

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We investigated the fungal entomopathogens Beauveria bassiana and Metarhizium anisopliae to determine if endophytic colonization could be achieved in cassava. An inoculation method based on drenching the soil around cassava stem cuttings using conidial suspensions resulted in endophytic colonization of cassava roots by both entomopathogens, though neither was found in the leaves or stems of the treated cassava plants. Both fungal entomopathogens were detected more often in the proximal end of the root than in the distal end. Colonization levels of B. bassiana were higher when plants were sampled at 7-9 days post-inoculation (84%) compared to 47-49 days post-inoculation (40%). In contrast, the colonization levels of M. anisopliae remained constant from 7-9 days post-inoculation (80%) to 47-49 days post-inoculation (80%), which suggests M. anisopliae is better able to persist in the soil, or as an endophyte in cassava roots over time. Differences in colonization success and plant growth were found among the fungal entomopathogen treatments.

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We conducted a survey of fungal endophytes in 582 germinated seeds belonging to 11 Colombian cultivars of the common bean (Phaseolus vulgaris). The survey yielded 394 endophytic isolates belonging to 42 taxa, as identified by sequence analysis of the ribosomal DNA internal transcribed spacer (ITS) region. Aureobasidium pullulans was the dominant endophyte, isolated from 46.7 % of the samples. Also common were Fusarium oxysporum, Xylaria sp., and Cladosporium cladosporioides, but found in only 13.4 %, 11.7 %, and 7.6 % of seedlings, respectively. Endophytic colonization differed significantly among common bean cultivars and seedling parts, with the highest colonization occurring in the first true leaves of the seedlings.

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Beauveria bassiana is a fungal entomopathogen with the ability to colonize plants endophytically. As an endophyte, B. bassiana may play a role in protecting plants from herbivory and disease. This protocol demonstrates two inoculation methods to establish B. bassiana endophytically in the common bean (Phaseolus vulgaris), in preparation for subsequent evaluations of endophytic biological control. Plants are grown from surface-sterilized seeds for two weeks before receiving a B. bassiana treatment of 10(8) conidia/ml (or water) applied either as a foliar spray or a soil drench. Two weeks later, the plants are harvested and their leaves, stems and roots are sampled to evaluate endophytic fungal colonization. For this, samples are individually surface sterilized, cut into multiple sections, and incubated in potato dextrose agar media for 20 days. The media is inspected every 2-3 days to observe fungal growth associated with plant sections and record the occurrence of B. bassiana to estimate the extent of its endophytic colonization. Analyses of inoculation success compare the occurrence of B. bassiana within a given plant part (i.e. leaves, stems or roots) across treatments and controls. In addition to the inoculation method, the specific outcome of the experiment may depend on the target crop species or variety, the fungal entomopathogen species strain or isolate used, and the plant's growing conditions.

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The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is the most important coffee pest worldwide. Beauveria bassiana is a generalist entomopathogenic fungus widely used by coffee farmers to control this pest and Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) is an African endoparasitoid of H. hampei adults, recently imported to several Latin American and Caribbean countries to aid in the coffee berry borer control. The objective of this study was to determine if B. bassiana is detrimental to P. coffea. The susceptibility of the parasitoid was evaluated in terms of adult survivorship, mean lethal concentration (LC50), mean lethal time (LT50), reproduction and immature mortality. The main effect of the fungus resulted in reduction of adult longevity and mortality of 100% for immature stages of this parasitoid. The LC50 for adults was 0.11% equivalent to 9.53 x 10(7) conidia/ml of B. bassiana and a LT50 of 29.4h, equivalent to reduction of 22% of its normal longevity as an adult. P. coffea was capable of disseminating spores of B. bassiana to non-infected H. hampei adults, which could indirectly cause the death of its own progeny. These results could be valuable when considering the use of both organisms in the field, especially in an integrated pest management program.

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La broca del café, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), es la plaga mas importante del cultivo de café en el mundo. Beauveria bassiana es un hongo entomopatógeno generalista ampliamente utilizado por los productores de café para controlar a H. hampei. Phymastichus coffea LaSalle es un endoparasitoide africano de adultos de la broca, recién importado a varios países de Latinoamérica y del Caribe para el control de esta plaga. En el presente estudio se realizaron bioensayos de laboratorio con el objetivo de determinar si B. bassiana es detrimental para el parasitoide P. coffea. La susceptibilidad del parasitoide fue evaluada en términos de supervivencia de adultos, concentración letal media (CL50), tiempo letal medio (TL50), reproducción y mortalidad de su progenie. El principal efecto del hongo resultó en la disminución de la longevidad de los adultos y en la mortalidad del 100 por ciento de los inmaduros del parasitoide. La CL50 para adultos de P. coffea fue de 0.11 por ciento equivalente a 9.53 x 10(7) conidias/ml de B. bassiana y una TL50 de 29.4h, equivalente a la reducción del 22 por ciento de su longevidad normal como adulto. P. coffea fue capaz de transmitir esporas de B. bassiana a brocas no infectadas con el hongo y originar indirectamente la muerte de su progenie. Este trabajo servirá de referencia cuando se contemple el empleo de ambos organismos a nivel de campo, especialmente dentro de un plan de manejo integral de la plaga.

The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is the most important coffee pest worldwide. Beauveria bassiana is a generalist entomopathogenic fungus widely used by coffee farmers to control this pest and Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) is an African endoparasitoid of H. hampei adults, recently imported to several Latin American and Caribbean countries to aid in the coffee berry borer control. The objective of this study was to determine if B. bassiana is detrimental to P. coffea. The susceptibility of the parasitoid was evaluated in terms of adult survivorship, mean lethal concentration (LC50), mean lethal time (LT50), reproduction and immature mortality. The main effect of the fungus resulted in reduction of adult longevity and mortality of 100 percent for immature stages of this parasitoid. The LC50 for adults was 0.11 percent equivalent to 9.53 x 10(7) conidia/ml of B. bassiana and a LT50 of 29.4h, equivalent to reduction of 22 percent of its normal longevity as an adult. P. coffea was capable of disseminating spores of B. bassiana to non-infected H. hampei adults, which could indirectly cause the death of its own progeny. These results could be valuable when considering the use of both organisms in the field, especially in an integrated pest management program.

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Coffee is predicted to be severely affected by climate change. We determined the thermal tolerance of the coffee berry borer, Hypothenemus hampei, the most devastating pest of coffee worldwide, and make inferences on the possible effects of climate change using climatic data from Colombia, Kenya, Tanzania, and Ethiopia. For this, the effect of eight temperature regimes (15, 20, 23, 25, 27, 30, 33 and 35 degrees C) on the bionomics of H. hampei was studied. Successful egg to adult development occurred between 20-30 degrees C. Using linear regression and a modified Logan model, the lower and upper thresholds for development were estimated at 14.9 and 32 degrees C, respectively. In Kenya and Colombia, the number of pest generations per year was considerably and positively correlated with the warming tolerance. Analysing 32 years of climatic data from Jimma (Ethiopia) revealed that before 1984 it was too cold for H. hampei to complete even one generation per year, but thereafter, because of rising temperatures in the area, 1-2 generations per year/coffee season could be completed. Calculated data on warming tolerance and thermal safety margins of H. hampei for the three East African locations showed considerably high variability compared to the Colombian site. The model indicates that for every 1 degrees C rise in thermal optimum (T(opt.)), the maximum intrinsic rate of increase (r(max)) will increase by an average of 8.5%. The effects of climate change on the further range of H. hampei distribution and possible adaption strategies are discussed. Abstracts in Spanish and French are provided as supplementary material Abstract S1 and Abstract S2.

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A phylogenetic epidemiological study of Beauveria bassiana s.l. was conducted for African and Neotropical pathogens of the coffee berry borer (CBB), Hypothenemus hampei, based on inferences from two nuclear intergenic regions, EFutr and Bloc. CBB pathogens were distributed among four terminal clades, however, the majority of African and Neotropical isolates cluster in a well-supported monophyletic group, informally designated AFNEO_1. Although the relationship between African and Neotropical AFNEO_1 is unresolved, the majority of alleles detected were exclusive to either the African or the Neotropical populations. These fixed genetic differences suggest that their disjunction predates the world trade in coffee. Neotropical AFNEO_1 have a broad host range and CBB pathogens are intermixed phylogenetically with isolates from diverse indigenous insects. Several Neotropical AFNEO_1 isolates were isolated from coffee plants as epiphytes or endophytes, thus plants themselves may potentially serve as reservoirs of pathogens against their insect pests. Topological incongruence between the EFutr and Bloc phylogenies of Neotropical AFNEO_1 may signify that individuals within this population are recombining.

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