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Sample records for gordura melinis minutiflora

  1. Henneguya melini n. sp. (Myxosporea: Myxobolidae), a parasite of Corydoras melini (Teleostei: Siluriformes) in the Amazon region: morphological and ultrastructural aspects.

    PubMed

    Mathews, Patrick D; Maia, Antônio A M; Adriano, Edson A

    2016-09-01

    A new species of myxozoan, Henneguya melini sp. n. (Myxosporea: Myxobolidae), was described based on morphologic and ultrastructural features. This is a parasite of the ornamental freshwater fish C. melini from the Rio Negro, and it was found in five of 30 (16.7 %) C. melini examined. The parasite was found in the gill filaments, and the plasmodia had form of round to ellipsoid, with mature and immature spores inside them. The average spore body was 15.5 ± 0.2 μm in length, 4.7 ± 0.1 μm in width, and the tail measured 25.3 ± 0.1 μm in length. The spores showed typical features of the genus Henneguya, with two valves of equal size and two symmetrical polar capsules of 4.8 ± 0.7 μm in length and 1.7 ± 0.3 μm in width. Each polar capsule had a polar filament with five to six turns. Based on morphology (morphologic and ultrastructural data) of the plasmodia and spores and the fact that this is the first report of a Henneguya species in a fish species of the genus Corydoras, it was considered a new myxozoan species. PMID:27206653

  2. Morphological and ultrastructural aspects of Myxobolus niger n. sp. (Myxozoa) gill parasite of Corydoras melini (Siluriformes: Callichthyidae) from Brazilian Amazon.

    PubMed

    Mathews, Patrick D; Maia, Antônio A M; Adriano, Edson A

    2016-06-01

    Myxobolus niger n. sp. (Myxozoa) is described in the connective tissue of the serosa layer of the gill arch of Corydoras melini (Callichthyidae) captured from the Negro River, Amazonas State, Brazil. The prevalence of the parasite was 20% and the range intensity was 1-2 cysts per fish. The plasmodia were white and spherical to ellipsoidal, measuring 175 μm in diameter and were surrounded by a well-defined capsule of host connective tissue, with distinct delicate and interlaced collagen fibers. The myxospores body was ellipsoidal in frontal view and biconvex in sutural view. Spore dimensions were 11.3 ± 0.4 μm in length, 6.8 ± 0.2 μm in width and 4.1 ± 0.2 μm in thickness. The valves were symmetrical and smooth. The two polar capsules were elongated as pyriform and equal in size, measure 5.0 ± 0.3 μm in length and 2.0 ± 0.1 μm in width. The polar capsule had six to seven polar filament turns. Some aberrant spores were round in shape and had three polar capsules. The sporoplasm was binucleated and contained moderated number of sporoplasmosomes. The development of the plasmodia was asynchronic, with mature and immature spores. The plasmodium had moderated pynocitic channels. There were no projections, no invaginations and no microvilli in the plasmodial wall. This study is the first description of Myxobolus species in the fish of the Callichthyidae family. PMID:26992296

  3. Ultrastructure and ssrRNA sequencing of Myxidium amazonense n. sp. a myxosporean parasite of Corydoras melini from the Rio Negro river, Amazonas state, Brazil.

    PubMed

    Mathews, Patrick D; Silva, Marcia R M; Maia, Antônio A M; Adriano, Edson A

    2015-12-01

    In a survey of myxozoan parasites of ornamental freshwater fish from the Rio Negro river, it was found that seven of 30 (23.3 %) Corydoras melini specimens examined had plasmodia of a new Myxidium species (Myxidium amazonense n. sp.) in the gallbladder. The fish were caught in the Rio Negro river, in the municipality of Santa Isabel do Rio Negro, in the state of Amazonas, Brazil. The plasmodia had a tubular shape, which was organized as a spiral spring with several turns in the gallbladder. The development of the myxospores was asynchronic, with disporic pansporoblasts. Mature myxospores were elongated, with 17.0 ± 0.9 (16.1-17.9) μm in length and 3.7 ± 0.7 (3.0-4.4) μm in width, and lightly arcuate from the valval view, with their bodies tapering slowly until ending in rounded extremities. The valval surface had nine to ten grooves in each valve. The polar capsules, one at either end of the spore, had a length of 5.4 ± 0.5 (4.9-5.9) μm and a width of 3.4 ± 0.6 (2.8-4.0) μm. Ultrastructural analysis showed that the wall of the plasmodia had numerous microvilli-like structures, pinocytotic canals, and cytoplasmic bridges connecting the pansporoblasts to each other and to the ectoplasm zone. Phylogenetic analysis, based on a small subunit ribosomal RNA (ssrRNA), identified the new species as a sister species of Myxidiumceccarelli, the unique South American Myxidium species whose ssrRNA sequence is available in the NCBI database. This study is the first description of Myxidium species in ornamental freshwater fish from Amazon. PMID:26341802

  4. Long-term impacts of invasive grasses and subsequent fire in seasonally dry Hawaiian woodlands.

    PubMed

    D'Antonio, Carla M; Hughes, R F; Tunison, J T

    2011-07-01

    Invasive nonnative grasses have altered the composition of seasonally dry shrublands and woodlands throughout the world. In many areas they coexist with native woody species until fire occurs, after which they become dominant. Yet it is not clear how long their impacts persist in the absence of further fire. We evaluated the long-term impacts of grass invasions and subsequent fire in seasonally dry submontane habitats on Hawai'i, USA. We recensused transects in invaded unburned woodland and woodland that had burned in exotic grass-fueled fires in 1970 and 1987 and had last been censused in 1991. In the unburned woodlands, we found that the dominant understory grass invader, Schizachyrium condensatum, had declined by 40%, while native understory species were abundant and largely unchanged from measurements 17 years ago. In burned woodland, exotic grass cover also declined, but overall values remained high and recruitment of native species was poor. Sites that had converted to exotic grassland after a 1970 fire remained dominated by exotic grasses with no increase in native cover despite 37 years without fire. Grass-dominated sites that had burned twice also showed limited recovery despite 20 years of fire suppression. We found limited evidence for "invasional meltdown": Exotic richness remained low across burned sites, and the dominant species in 1991, Melinis minutiflora, is still dominant today. Twice-burned sites are, however, being invaded by the nitrogen-fixing tree Morella faya, an introduced species with the potential to greatly alter the successional trajectory on young volcanic soils. In summary, despite decades of fire suppression, native species show little recovery in burned Hawaiian woodlands. Thus, burned sites appear to be beyond a threshold for "natural recovery" (e.g., passive restoration). PMID:21830706

  5. Exploiting phytochemicals for developing a 'push-pull' crop protection strategy for cereal farmers in Africa.

    PubMed

    Khan, Zeyaur R; Midega, Charles A O; Bruce, Toby J A; Hooper, Antony M; Pickett, John A

    2010-10-01

    Lepidopteran stemborers and parasitic weeds in the genus Striga are major constraints to efficient production of cereals, the most important staple food crops in Africa. Smallholder farmers are resource constrained and unable to afford expensive chemicals for crop protection. Development of a push-pull approach for integrated pest and weed management is reviewed here. Appropriate plants were discovered that naturally emit signalling chemicals (semiochemicals). Plants highly attractive for egg laying by stemborer pests were selected and employed as trap crops (pull), to draw pests away from the main crop. Of these, Napier grass, Pennisetum purpureum (Schumach), despite its attractiveness, supported minimal survival of the pests' immature stages. Plants that repelled stemborer pests, notably molasses grass, Melinis minutiflora P. Beauv., and forage legumes in the genus Desmodium, were selected as intercrops (push). Desmodium intercrops suppress Striga hermonthica (Del.) Benth. through an allelopathic mechanism. Their root exudates contain novel flavonoid compounds, which stimulate suicidal germination of S. hermonthica seeds and dramatically inhibit its attachment to host roots. The companion crops provide valuable forage for farm animals while the leguminous intercrops also improve soil fertility and moisture retention. The system is appropriate as it is based on locally available plants, not expensive external inputs, and fits well with traditional mixed cropping systems in Africa. To date it has been adopted by more than 30,000 smallholder farmers in East Africa where maize yields have increased from ∼1 t ha(-1) to 3.5 t ha(-1). Future directions for semiochemical delivery by plants including biotechnological opportunities are discussed.

  6. EXPLOITING CHEMICAL ECOLOGY FOR LIVELIHOOD IMPROVEMENT OF SMALL HOLDER FARMERS IN KENYA.

    PubMed

    Winter, E; Midega, C; Bruce, T; Hummel, H E; Langner, S S; Leithold, G; Khan, Z; Pickett, J

    2014-01-01

    "Push-Pull" is an inexpensive and eminently practical strategy designed for developing countries in order to exploit sound principles of chemical ecology for agricultural pest management. This strategy is specifically suitable for small holder farmers. Their experience can easily be integrated into existing farming practices in their immediate environment. "Push-pull" within one and a half decades became widely established and meanwhile is greatly beneficial to practitioners in East Africa, mainly Kenya. The classical push-pull approach used for applied plant-insect management was pioneered by Khan and Pickett (2000) and subsequent papers of Pickett (2003) and Khan et al. (2006, 2008). Relevant plant species explored so far were maize or sorghum intercropped with other East African plants (Desmodium spp. resp. Melinis minutiflora) possessing natural chemicals repellent resp. attractive for stem borer moths Chilo partellus (Lepidoptera), whereby Desmodium spp. was grown inside the maize rows while M. minutiflora surrounded it. Both simultaneous actions combined resulted in a significant decrease of stem borers in the area to be protected. A benefit to cost ratio of 2.5 was realized. Within a period of 15 years the number of subscribing farmers substantially increased from a few dozen to more than 80,000 in 2014. Two experiments along the paths of chemical ecology were undertaken between Sept 2012 and Feb 2013: One was designed to investigate if the legume D. intortum known to produce repellent volatiles against stem borer moths induces defence in Zea mays varieties. We looked at two open-pollinated farmers' varieties and two commercial hybrid varieties suspecting the farmers' varieties to be responsive rather than the hybrids. However, no defence induction was detected in this study so far. This could be explained by an insufficient production of defence inducing volatiles in leaves of D. intortum whereas flowers might produce a sufficient response. More detailed

  7. EXPLOITING CHEMICAL ECOLOGY FOR LIVELIHOOD IMPROVEMENT OF SMALL HOLDER FARMERS IN KENYA.

    PubMed

    Winter, E; Midega, C; Bruce, T; Hummel, H E; Langner, S S; Leithold, G; Khan, Z; Pickett, J

    2014-01-01

    "Push-Pull" is an inexpensive and eminently practical strategy designed for developing countries in order to exploit sound principles of chemical ecology for agricultural pest management. This strategy is specifically suitable for small holder farmers. Their experience can easily be integrated into existing farming practices in their immediate environment. "Push-pull" within one and a half decades became widely established and meanwhile is greatly beneficial to practitioners in East Africa, mainly Kenya. The classical push-pull approach used for applied plant-insect management was pioneered by Khan and Pickett (2000) and subsequent papers of Pickett (2003) and Khan et al. (2006, 2008). Relevant plant species explored so far were maize or sorghum intercropped with other East African plants (Desmodium spp. resp. Melinis minutiflora) possessing natural chemicals repellent resp. attractive for stem borer moths Chilo partellus (Lepidoptera), whereby Desmodium spp. was grown inside the maize rows while M. minutiflora surrounded it. Both simultaneous actions combined resulted in a significant decrease of stem borers in the area to be protected. A benefit to cost ratio of 2.5 was realized. Within a period of 15 years the number of subscribing farmers substantially increased from a few dozen to more than 80,000 in 2014. Two experiments along the paths of chemical ecology were undertaken between Sept 2012 and Feb 2013: One was designed to investigate if the legume D. intortum known to produce repellent volatiles against stem borer moths induces defence in Zea mays varieties. We looked at two open-pollinated farmers' varieties and two commercial hybrid varieties suspecting the farmers' varieties to be responsive rather than the hybrids. However, no defence induction was detected in this study so far. This could be explained by an insufficient production of defence inducing volatiles in leaves of D. intortum whereas flowers might produce a sufficient response. More detailed

  8. Plant and root endophyte assembly history: interactive effects on native and exotic plants.

    PubMed

    Sikes, Benjamin A; Hawkes, Christine V; Fukami, Tadashi

    2016-02-01

    Differences in the arrival timing of plants and soil biota may result in different plant communities through priority effects, potentially affecting the success of native vs. exotic plants, but experimental evidence is largely lacking. We conducted a greenhouse experiment to investigate whether the assembly history of plants and fungal root endophytes could interact to influence plant emergence and biomass. We introduced a grass species and eight fungal species from one of three land-use types (undisturbed, disturbed, or pasture sites in a Florida scrubland) in factorial combinations. We then introduced all plants and fungi from the other land-use types 2 weeks later. Plant emergence was monitored for 6 months, and final plant biomass and fungal species composition assessed. The emergence and growth of the exotic Melinis repens and the native Schizacharyium niveum were affected negatively when introduced early with their "home" fungi, but early introduction of a different plant species or fungi from a different site type eliminated these negative effects, providing evidence for interactive priority effects. Interactive effects of plant and fungal arrival history may be an overlooked determinant of plant community structure and may provide an effective management tool to inhibit biological invasion and aid ecosystem restoration. PMID:27145622

  9. Plant and root endophyte assembly history: interactive effects on native and exotic plants.

    PubMed

    Sikes, Benjamin A; Hawkes, Christine V; Fukami, Tadashi

    2016-02-01

    Differences in the arrival timing of plants and soil biota may result in different plant communities through priority effects, potentially affecting the success of native vs. exotic plants, but experimental evidence is largely lacking. We conducted a greenhouse experiment to investigate whether the assembly history of plants and fungal root endophytes could interact to influence plant emergence and biomass. We introduced a grass species and eight fungal species from one of three land-use types (undisturbed, disturbed, or pasture sites in a Florida scrubland) in factorial combinations. We then introduced all plants and fungi from the other land-use types 2 weeks later. Plant emergence was monitored for 6 months, and final plant biomass and fungal species composition assessed. The emergence and growth of the exotic Melinis repens and the native Schizacharyium niveum were affected negatively when introduced early with their "home" fungi, but early introduction of a different plant species or fungi from a different site type eliminated these negative effects, providing evidence for interactive priority effects. Interactive effects of plant and fungal arrival history may be an overlooked determinant of plant community structure and may provide an effective management tool to inhibit biological invasion and aid ecosystem restoration.

  10. Environmental Attributes Influencing the Distribution of Burkholderia pseudomallei in Northern Australia

    PubMed Central

    Baker, Anthony L.; Ezzahir, Jessica; Gardiner, Christopher; Shipton, Warren; Warner, Jeffrey M.

    2015-01-01

    Factors responsible for the spatial and temporal clustering of Burkholderia pseudomallei in the environment remain to be elucidated. Whilst laboratory based experiments have been performed to analyse survival of the organism in various soil types, such approaches are strongly influenced by alterations to the soil micro ecology during soil sanitisation and translocation. During the monsoonal season in Townsville, Australia, B. pseudomallei is discharged from Castle Hill (an area with a very high soil prevalence of the organism) by groundwater seeps and is washed through a nearby area where intensive sampling in the dry season has been unable to detect the organism. We undertook environmental sampling and soil and plant characterisation in both areas to ascertain physiochemical and macro-floral differences between the two sites that may affect the prevalence of B. pseudomallei. In contrast to previous studies, the presence of B. pseudomallei was correlated with a low gravimetric water content and low nutrient availability (nitrogen and sulphur) and higher exchangeable potassium in soils favouring recovery. Relatively low levels of copper, iron and zinc favoured survival. The prevalence of the organism was found to be highest under the grasses Aristida sp. and Heteropogon contortus and to a lesser extent under Melinis repens. The findings of this study indicate that a greater variety of factors influence the endemicity of melioidosis than has previously been reported, and suggest that biogeographical boundaries to the organisms’ distribution involve complex interactions. PMID:26398904

  11. CAT: the INGV Tsunami Alert Center

    NASA Astrophysics Data System (ADS)

    Michelini, A.

    2014-12-01

    After the big 2004 Sumatra earthquake, the tsunami threat posed by large earthquakes occurring in the Mediterranean sea was formally taken into account by many countries around the Mediterranean basin. In the past, large earthquakes that originated significant tsunamis occurred nearly once per century (Maramai et al., 2014, Annals of Geophysics). The Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO) received a mandate from the international community to coordinate the establishment of the ICG/NEAMTWS (http://neamtic.ioc-unesco.org) through Resolution IOC-XXIII-14. Since then, several countries (France, Turkey, Greece) have started operating as candidate Tsunami Watch Provider (cTWP) in the Mediterranean. Italy started operating as cTWP on October 1st, 2014. The Italian cTWP is formed by INGV ("Istituto Nazionale di Geofisica e Vulcanologia)", DPC ("Dipartimento di Protezione Civile") and ISPRA ("Istituto Superiore per la Protezione e la Ricerca Ambientale"). INGV is in charge of issuing the alert for potentially tsunamigenic earthquakes, ISPRA provides the sea level recordings and DPC is in charge of disseminating the alert. INGV established the tsunami alert center (CAT, "Centro di Allerta Tsunami") at the end of 2013. CAT is co-located with the INGV national seismic surveillance center operated since many years. In this work, we show the technical and personnel organization of CAT, its response to recent earthquakes, and the new procedures under development for implementation. (*) INGV-CAT WG: Amato A., Basili R., Bernardi F., Bono A., Danecek P., De Martini P.M., Govoni A., Graziani L., Lauciani V., Lomax, A., Lorito S., Maramai A., Mele F., Melini D., Molinari I., Nostro C., Piatanesi A., Pintore S., Quintiliani M., Romano F., Selva J., Selvaggi G., Sorrentino D., Tonini R.

  12. Cardiovascular risk factors in children and adolescents with anxiety disorders and their association with disease severity.

    PubMed

    Cheuiche Pires, Gabriela; Camboim Rockett, Fernanda; Abrahão Salum Júnior, Giovanni; Gus Manfro, Gisele; Bosa, Vera Lúcia

    2005-01-01

    Introducción: Evidencias sugieren que la ansiedad es una prediciente independiente de los eventos cardiovasculares adversos. Entretanto, pocos estudios evaluaron la presencia de factores de riesgo (FR) para estas enfermedades en ninos y adolescentes. Objetivos: Identificar la prevalencia de FR cardiovasculares en ninos y adolescentes diagnosticados con disturbio de ansiedad y su asociacion con la gravedad de la enfermedad. Metodología: Estudio transversal que avaluo FR nutricional, antropometricos, % de gordura corporal (CG), presion arterial (PA), nivel de actividad fisica y escalas de sintomas y gravedad de la ansiedad. Resultados: 65 ninos y adolescentes (8.6 } 1.7 anos) fueron incluidos en el estudio. Cuanto a los FR, el consumo excesivo de acidos grasos saturados (52.3%), indice de masa corporal alto (50.8%), PA alterada (50.8%) y la falta de ejercicio fisico (50.0%) fueron los mas prevalecientes. Hubo asociacion significativa entre la mayor gravedad del disturbio y el acumulo de ≥ 6 FR (p=0,026), exceso de gordura abdominal medida por la circunferencia de cintura (p=0.019) y por el indice de conicidad (p=0.053) y exceso en el % GC (p=0.044). Conclusión: Los resultados encontrados indican que hay una alta prevalencia de FR cardiovascular en la amuestra estudiada y los pacientes mas graves presentaron mayor riesgo. La caracterizacion del perfil de riesgo en las poblaciones con predisposicion a las enfermedades cardiovasculares es crucial para la elaboracion de estrategias de intervencion que oportunicen la reduccion en la prevalencia de estas enfermedades.