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Sample records for grasshopper zonocerus variegatus

  1. Secondary Metabolites of the Cuticular Abdominal Glands of Variegated Grasshopper (Zonocerus variegatus L.

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    O. U. Igwe

    2015-01-01

    Full Text Available Chemical compounds were extracted with petroleum ether from the cuticular abdominal glands of grasshopper (Zonocerus variegatus L. and eleven compounds were characterised using Gas Chromatography/Mass Spectrometry (GC/MS technique in combination with Fourier Transform-Infrared Spectroscopy (FT-IR. The compounds analysed were 2,7-dimethyloctane (3.21%, decane (5.33%, undecane (3.81%, tridecanoic acid methyl ester (4.76%, hexadecanoic acid (9.37%, 11-octadecenoic acid methyl ester (23.18%, pentadecanoic acid, 14-methyl-methyl ester (4.43%, (Z-13-docosenoic acid (10.71%, dodecyl pentafluoropropionate (9.52%, 2-dodecyl-1,3-propanediol (6.38%, and 1,12-tridecadiene (19.30%. FT-IR analysis of the extract showed peaks at 1270.17 (C–O and C–F, 1641.48 (C=C, 2937.68 (C–H, and 3430.51 (O–H cm−1 indicating the presence of ether, alkene, alkane, alcohol, carboxylic acid, and fluoric compounds. These compounds consisted of 32.37% ester, 31.65% hydrocarbons, 20.08% fatty acid, 9.52% halogenated ester, and 6.38% alcohol. The highest component was 11-octadecenoic acid methyl ester followed by 1,12-tridecadiene. Since behavioural bioassays were not carried out, the consideration of these compounds to be pheromone semiochemicals remains a hypothesis.

  2. Sexual differences in destructive capability and midgut enzyme activities in adult variegated grasshoppers Zonocerus variegatus (LINNAEUS, 1758 (Orthoptera: Pyrgomorphidae

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    Ademolu Kehinde O.

    2016-12-01

    Full Text Available The variegated grasshopper Zonocerus variegatus is a polyphagous insect, feeding on numerous food and cash crops. The present study aimed to investigate the sexual variations in the destructive capability of the adult insects and the composition of leaves damaged by them, as well as in the levels of midgut microbial flora and digestive enzymes (cellulase, amylase and α-glucosidase. The results showed that females consumed and caused more damage to cassava leaves than their male congeners. The leaves damaged by males contained more nutrients than those damaged by females. The gut microbial flora and enzyme assay showed that females had significantly larger colony forming units and a non-significant difference in enzyme activities. It can thus be concluded that adult females are more destructive than males.

  3. Microbial control of caged population of Zonocerus variegatus using ...

    African Journals Online (AJOL)

    Microbial control of caged populations of Zonocerus variegatus was carried out using indigenous fungal entomopathogens isolated from the grasshopper's cadaver. Bioassay response indicated a dose-dependent mortality coupled with drastic reduction in food consumption among spores infected grasshoppers. Lethal time ...

  4. Entomopathogenic fungi in population of Zonocerus variegatus (l) in ...

    African Journals Online (AJOL)

    Field survey of population of Zonocerus variegatus revealed a high fungal incidence of 76% when Sporulation tests were carried out on grasshoppers cadaver. Eight fungi with differing incidence rates were isolated. These are Fusarium sp. (8%); Beauveria bassiana (18%); Metarhizium sp. (20%); Aspergillus flavus (10%); ...

  5. Circadian variation in metabolite and enzyme activities in the femoral and thoracic muscles of adult variegated grasshoppers, Zonocerus variegatus (Linnaeus, 1758 (Orthoptera: Pyrgomorphidae

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    Ademolu Kehinde Olutoyin

    2018-03-01

    Full Text Available The African variegated grasshopper, Zonocerus variegatus, exhibits daily variations in its feeding and destructive activities. A study to investigate circadian variation in metabolites (lipids, protein, glucose, K+, Ca2+, Mg2+, Cl− concentrations and enzymes (lipase, amylase, proteinase, α-glucosidase activities in the femoral and thoracic muscles of adult Z. variegatus was carried out by collecting samples at 06:00, 12:00, 18:00 and 24:00 hrs GMT. The four enzymes were present throughout the day in both thoracic and femoral muscles but at varying levels. Significantly (p<0.05 higher enzymes activities were measured during the day (between 06:00 and 18:00 hours GMT (except proteinase than at night (24:00 hrs. Organic substances in the two tissues were present in significantly higher concentrations during the day than at night. Similarly, significantly more inorganic substances were recorded in the afternoon (12:00-18:00 hrs than at night in both femoral and thoracic muscles. It can thus be concluded that locomotor activities in Z. variegatus reach a peak during the day.

  6. Tolerating Toxins: Grasshoppers that Feast on Pyrrolizidine Alkaloids §.

    Science.gov (United States)

    Housecroft, Catherine E

    2018-03-30

    The elegant grasshopper (Zonocerus elegans) and the variegated grasshopper (Z. variegatus) are among insects that deliberately consume and store pyrrolizidine alkaloids which are subsequently used in defence mechanisms.

  7. The attraction of Zonocerus variegatus (Orthoptera: Pyrgomorphidae to different types of lure

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    A. Babatunde Idowu

    2001-06-01

    Full Text Available Zonocerus variegatus is a common grasshopper in parts of west and equtorial Africa.The distribution in Nigeria extends from the lowland rainforest zone to the savannah in the north. The influence of lure on the behaviour of grasshopper inside cages (120 insect per cage was investigated. Nymphs and adults of Zonocerus variegatus responded positively to intact leaves,crushed leaves and inflorescence of the common compositae weed Chromolaena odorata inside muslin bags, and intact plants. There were significant differences in the attraction recorded for starved nymphs, fed nymphs and starved adults. Attraction was more to intact leaves and is by olfaction. The increase in the attraction of starved nymphs is time dependent. Attraction to plant parts ceased after the plants were dried for 24 and 48 hours at room temperature and when plants were placed in transparent polythene bags. Gut motility and gut activity were higher during the day than at night. Nymphs, adults and egg pods placed separately inside muslin bags were not attractive to adults or nymphs.Zococerus variegatus es un saltamontes común en partes de Africa ecuatorial y oeste. La distribución en Nigeria se extiende desde la zona baja del bosque lluvioso hasta la sabana en el norte. La influencia del cebo sobre el comportamiento del saltamontes dentro de las jaulas (120 insectos por jaula fue investigada. Las ninfas y los adultos de Z. variegatus respondieron positivamente a hojas intactas, hojas aplastadas e inflorescencias de la hierba común compuesta Chromolaena odorata dentro de bolsas de muselina y a plantas intactas. Hubo diferencias significativas en la atracción registrada en ninfas mantenidas con hambre, ninfas alimentadas y adultos mantenidos con hambre. La atracción fue más hacia hojas intactas y fue por olfato. El aumento en la atracción de ninfas mantenidas con hambre fue tiempo-dependiente. La atracción a partes de plantas paró luego de que las plantas fueron secadas

  8. Nutritional evaluation of the giant grassropper (Zonocerus ...

    African Journals Online (AJOL)

    The biological value of giant grasshopper protein (Zonocerus variegatus) was evaluated by comparing the weight gained, food efficiency ratio (FER), protein efficiency ratio (PER) of rats fed standard laboratory chow with that of rats fed giant grasshopper, Soyabean(Glycine max) and crayfish. The effect of high fibre content ...

  9. Species composition of grasshoppers (Orthoptera) in open plots and farmlands in calabar metropolis, southern Nigeria.

    Science.gov (United States)

    Oku, E E; Arong, G A; Bassey, D A

    2011-04-15

    The grasshoppers are strategic in the welfare of man and may constitute a major threat when its population is not checked. A study on the distribution of grasshoppers in open plots and farmlands was carried out within Calabar Metropolis between August to November, 2010. A total of 295 grasshoppers belonging to 11 species grouped under 3 families (Tettigoniidae, Acrididae and Pyrgomorphidae) were collected from 8 study locations. Grasshoppers were collected weekly from all study sites using sweep nets between 11 a.m. to 4 p.m. The collection was done using sweep nets between 11 a.m. to 4 p.m. when grasshoppers baked themselves under the sun. The percentage abundance of these species were Spathosterrium pygmaeum (16.27%), Tettigonia viridissima (11.86%), Catantops spissus (11.19%) Acridaturita sp. (10.17%), Gastrimargus acrididae (9.83%), Schistocerca nitens (9.49%), Tylopsis sp. (7.46%), Zonocerus variegatus (6.78%), Omocestus viridulus (6.10%), Scudderia mexicana (5.76%) and Zonocerus elegans (5.08%). Tettigonia viridissima and Acridaturita sp. were largely distributed as it occurred in 7 of 8 study sites while Scudderia mexicana was the least distributed, as it was reported in 3 sites only. The dominant grasshopper species in open plot was Spathosterrium pygmaeum (19%) in relative abundance and the least was Zonocerus variegatus (0.64%). Zonocerus variegatus was the dominant species in farmland (14%) in relative abundance and the least was Schistocerca nitens (4%). Chi-square test showed a high significant difference between the distribution of grasshoppers in open plots and farmlands (p grasshopper species composition were attributed to lizard predation and management practices such as grass cutting, fertilizer and pesticide applications. It was therefore concluded that species abundance and population of grasshoppers could be enhanced by minimizing human activities that interfere with land use.

  10. Independent recruitment of a flavin-dependent monooxygenase for safe accumulation of sequestered pyrrolizidine alkaloids in grasshoppers and moths.

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    Linzhu Wang

    Full Text Available Several insect lineages have developed diverse strategies to sequester toxic pyrrolizidine alkaloids from food-plants for their own defense. Here, we show that in two highly divergent insect taxa, the hemimetabolous grasshoppers and the holometabolous butterflies, an almost identical strategy evolved independently for safe accumulation of pyrrolizidine alkaloids. This strategy involves a pyrrolizidine alkaloid N-oxygenase that transfers the pyrrolizidine alkaloids to their respective N-oxide, enabling the insects to avoid high concentrations of toxic pyrrolizidine alkaloids in the hemolymph. We have identified a pyrrolizidine alkaloid N-oxygenase, which is a flavin-dependent monooxygenase, of the grasshopper Zonocerus variegatus. After heterologous expression in E. coli, this enzyme shows high specificity for pyrrolizidine alkaloids of various structural types and for the tropane alkaloid atropine as substrates, a property that has been described previously for a pyrrolizidine alkaloid N-oxygenase of the arctiid moth Grammia geneura. Phylogenetic analyses of insect flavin-dependent monooxygenase sequences suggest that independent gene duplication events preceded the establishment of this specific enzyme in the lineages of the grasshoppers and of arctiid moths. Two further flavin-dependent monooxygenase sequences have been identified from Z. variegatus sharing amino acid identities of approximately 78% to the pyrrolizidine alkaloid N-oxygenase. After heterologous expression, both enzymes are also able to catalyze the N-oxygenation of pyrrolizidine alkaloids, albeit with a 400-fold lower specific activity. With respect to the high sequence identity between the three Z. variegatus sequences this ability to N-oxygenize pyrrolizidine alkaloids is interpreted as a relict of a former bifunctional ancestor gene of which one of the gene copies optimized this activity for the specific adaptation to pyrrolizidine alkaloid containing food plants.

  11. Independent recruitment of a flavin-dependent monooxygenase for safe accumulation of sequestered pyrrolizidine alkaloids in grasshoppers and moths.

    Science.gov (United States)

    Wang, Linzhu; Beuerle, Till; Timbilla, James; Ober, Dietrich

    2012-01-01

    Several insect lineages have developed diverse strategies to sequester toxic pyrrolizidine alkaloids from food-plants for their own defense. Here, we show that in two highly divergent insect taxa, the hemimetabolous grasshoppers and the holometabolous butterflies, an almost identical strategy evolved independently for safe accumulation of pyrrolizidine alkaloids. This strategy involves a pyrrolizidine alkaloid N-oxygenase that transfers the pyrrolizidine alkaloids to their respective N-oxide, enabling the insects to avoid high concentrations of toxic pyrrolizidine alkaloids in the hemolymph. We have identified a pyrrolizidine alkaloid N-oxygenase, which is a flavin-dependent monooxygenase, of the grasshopper Zonocerus variegatus. After heterologous expression in E. coli, this enzyme shows high specificity for pyrrolizidine alkaloids of various structural types and for the tropane alkaloid atropine as substrates, a property that has been described previously for a pyrrolizidine alkaloid N-oxygenase of the arctiid moth Grammia geneura. Phylogenetic analyses of insect flavin-dependent monooxygenase sequences suggest that independent gene duplication events preceded the establishment of this specific enzyme in the lineages of the grasshoppers and of arctiid moths. Two further flavin-dependent monooxygenase sequences have been identified from Z. variegatus sharing amino acid identities of approximately 78% to the pyrrolizidine alkaloid N-oxygenase. After heterologous expression, both enzymes are also able to catalyze the N-oxygenation of pyrrolizidine alkaloids, albeit with a 400-fold lower specific activity. With respect to the high sequence identity between the three Z. variegatus sequences this ability to N-oxygenize pyrrolizidine alkaloids is interpreted as a relict of a former bifunctional ancestor gene of which one of the gene copies optimized this activity for the specific adaptation to pyrrolizidine alkaloid containing food plants.

  12. The Contribution of food plants to the growth, development and ...

    African Journals Online (AJOL)

    The Contribution of food plants to the growth, development and fecundity of Zonocerus variegatus (L) ... African Journal of Biotechnology ... The performance of the variegated grasshopper, Zonocerus variegatus (L) fed on different food plants namely cassava (Manihot esculenta), pawpaw (Carica papaya) and acalypha ...

  13. Lumbriculus variegatus loading study

    Data.gov (United States)

    U.S. Environmental Protection Agency — Results from sediment bioaccumulation tests with Lumbriculus variegatus with evaluating the effects of organism loading density. This dataset is associated with the...

  14. A RANGELAND GRASSHOPPER INSURANCE PROGRAM

    OpenAIRE

    Skold, Melvin D.; Davis, Robert M.

    1995-01-01

    The incidence of benefits and costs from controlling rangeland grasshoppers on public grazing lands poses problems of economic efficiency and distributional equity. Public grasshopper control programs operate like public disaster assistance. However, grasshopper infestations are an insurable risk. This article proposes a rangeland grasshopper insurance program which reduces the economic inefficiencies and distributional inequities of the existing program.

  15. The microbial flora of the different gut regions of the variegated ...

    African Journals Online (AJOL)

    The microbial flora of the gut regions and gut contents of the variegated grasshopper Zonocerus variegatus instars was studied using the pour plate technique. The gut sections (Fore-, mid-, and hind-gut) harboured a variety organisms mainly bacteria, fungi and mould. Yeasts species isolated were Candida, ...

  16. Author Details

    African Journals Online (AJOL)

    Ezeakacha, FN. Vol 5, No 1 (2011) - Articles A Study on the Feeding and Growth Patterns of the Variegated Grasshopper Zonocerus Variegatus (L) in the Laboratory Abstract PDF. ISSN: 2070-0083. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL ...

  17. Author Details

    African Journals Online (AJOL)

    Development of a trap to contaminate variegated grasshoppers (Zonocerus variegatus L.) (Orthoptera: Pyrgomorphidae) with Metarrhyzium flavo-viride Gams & Rozsypal in the field. Details · Vol 40, No 1 (2007) - Articles Yam pests in the Ashanti and Brong Ahafo regions of Ghana: A study of farmers\\' indigenous technical ...

  18. A Study on the Feeding and Growth Patterns of the Variegated ...

    African Journals Online (AJOL)

    The feeding and growth patterns of the variegated grasshopper, Zonocerus variegatus (L) were studied in the laboratory to ascertain the amount of food intake, food assimilated and faeces excreted by its nymph and adult stages on a mixed diet of Cassava (Manihot esculenta) and Siam weed (Chromolaena odorata) leaves.

  19. Global Journal of Pure and Applied Sciences - Vol 8, No 4 (2002)

    African Journals Online (AJOL)

    The microbial flora of the different gut regions of the variegated grasshopper Zonocerus variegatus (L) (Orthoptera :Pyrgomorphidae) · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. A.B. Idowu, M. O. Edema, 447-454. http://dx.doi.org/10.4314/gjpas.v8i4.15992 ...

  20. Author Details

    African Journals Online (AJOL)

    A Study on the Feeding and Growth Patterns of the Variegated Grasshopper Zonocerus Variegatus (L) in the Laboratory Abstract PDF · Vol 5, No 1 (2011) - Articles Comparative Studies on the Larvicidal Action of Novaluron (Mosquiron® 100EC) and Moringa Oliefera (LAM) Seed Oil against Aedes Aegypti (Diptera: ...

  1. The radioactive grasshopper

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1966-06-15

    Full text: Grasshoppers are 'tagged' with radiation in order to trace their movements for purposes of agricultural research. They are fed on young wheat containing iridium-192; the radioactivity taken up by the grasshoppers can then be observed by a portable scintillation counter. Laboratory tests have shown the biological period of the iridium to be of the order of seven days, and that about one microcurie per insect is needed to enable them to be traced during two months. (author)

  2. The radioactive grasshopper

    International Nuclear Information System (INIS)

    1966-01-01

    Full text: Grasshoppers are 'tagged' with radiation in order to trace their movements for purposes of agricultural research. They are fed on young wheat containing iridium-192; the radioactivity taken up by the grasshoppers can then be observed by a portable scintillation counter. Laboratory tests have shown the biological period of the iridium to be of the order of seven days, and that about one microcurie per insect is needed to enable them to be traced during two months. (author)

  3. The grasshopper problem

    Science.gov (United States)

    Goulko, Olga; Kent, Adrian

    2017-11-01

    We introduce and physically motivate the following problem in geometric combinatorics, originally inspired by analysing Bell inequalities. A grasshopper lands at a random point on a planar lawn of area 1. It then jumps once, a fixed distance d, in a random direction. What shape should the lawn be to maximize the chance that the grasshopper remains on the lawn after jumping? We show that, perhaps surprisingly, a disc-shaped lawn is not optimal for any d>0. We investigate further by introducing a spin model whose ground state corresponds to the solution of a discrete version of the grasshopper problem. Simulated annealing and parallel tempering searches are consistent with the hypothesis that, for dcogs, where the integer n is close to π (arcsin⁡(√{π }d / 2 )) -1. We find transitions to other shapes for d ≳π-1 / 2.

  4. Households at Grasshopper Pueblo.

    Science.gov (United States)

    Reid, J. Jefferson; Whittlesey, Stephanie M.

    1982-01-01

    Describes the archaeological reconstruction of domestic life in Grasshopper, Arizona, a mogollon pueblo community which began around 1300 A.D. Categories of space and domestic activities are discussed. An analysis of variations in the patterns of household types within the pueblo is included. (AM)

  5. Comparative analysis of chromosomal localization of ribosomal and telomeric DNA markers in three species of Pyrgomorphidae grasshoppers

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    Olesya G. Buleu

    2017-09-01

    Full Text Available The karyotypes of three species of Pyrgomorphidae grasshoppers were studied: Zonocerus elegans (Thunberg, 1815, Pyrgomorpha guentheri (Burr, 1899 and Atractomorpha lata (Mochulsky, 1866. Data on karyotypes of P. guentheri and Z. elegans are reported here for the first time. All species have karyotypes consisting of 19 acrocentric chromosomes in males and 20 acrocentric chromosomes in females (2n♂=19, NF=19; 2n♀=20, NF=20 and X0/XX sex determination system. A comparative analysis of the localization of C-heterochromatin, clusters of ribosomal DNA, and telomere repeats revealed inter-species diversity in these cytogenetic markers. These differences indicate that the karyotype divergence in the species studied is not associated with structural chromosome rearrangements, but with the evolution of repeated DNA sequences.

  6. Grasshopper species composition shifts following a severe rangeland grasshopper outbreak

    Science.gov (United States)

    Little is known about how grasshopper species abundances shift during and following severe outbreaks, as sampling efforts usually end when outbreaks subside. Grasshopper densities, species composition and vegetation have infrequently been sampled during and after a severe outbreak in the western U.S...

  7. Grasshoppers as a food source? A review

    Directory of Open Access Journals (Sweden)

    Paul, A.

    2016-01-01

    Full Text Available Description of the subject. Current trends suggest an increasing future demand for conventional meats, which indicates a strong need to shift this dependency to other alternative protein sources such as insects. Literature. From a nutritional point of view, of all the insects consumed globally, grasshoppers are particularly important as a human food. Data from the literature regarding the nutrient composition, amino acid profile, fatty acid profile, mineral composition and vitamin content of grasshoppers as reviewed in this paper, suggest that a number of grasshopper species are a good source of nutrients. It also highlights some of the health related aspects that might arise from the consumption of grasshoppers, mostly linked to agricultural practices and the allergic response of sensitive individuals. The paper also summarizes some religious, social and economic factors that are associated with grasshopper consumption. Conclusions. The success of introducing grasshoppers as a novel food in western countries depends on changes in consumer attitudes. It would be interesting to develop food products derived from grasshoppers in a form acceptable to consumers. Furthermore, it is important to explore the food potential of some grasshopper species native to western countries and to develop their rearing methodologies to enhance availability.

  8. Ferocious fighting between male grasshoppers.

    Directory of Open Access Journals (Sweden)

    Kate D L Umbers

    Full Text Available Contests among individuals over mating opportunities are common across diverse taxa, yet physical conflict is relatively rare. Due to the potentially fatal consequences of physical fighting, most animals employ mechanisms of conflict resolution involving signalling and ritualistic assessment. Here we provide the first evidence of ubiquitous escalated fighting in grasshoppers. The chameleon grasshopper (Kosciuscola tristis is an Australian alpine specialist, in which males engage in highly aggressive combat over ovipositing females. We describe discrete agonistic behaviours including mandible flaring, mounting, grappling, kicking and biting, and their use depending on the individual's role as challenger or defender. We show that male role predicts damage, with challengers being more heavily damaged than males defending females (defenders. Challengers also possess wider mandibles than defenders, but are similar in other metrics of body size. Our data suggest that fights escalate between males matched in body size and that mandibles are used as weapons in this species. This system represents an exciting opportunity for future research into the evolution of costly fighting behaviour in an otherwise placid group.

  9. Ferocious Fighting between Male Grasshoppers

    Science.gov (United States)

    Umbers, Kate D. L.; Tatarnic, Nikolai J.; Holwell, Gregory I.; Herberstein, Marie E.

    2012-01-01

    Contests among individuals over mating opportunities are common across diverse taxa, yet physical conflict is relatively rare. Due to the potentially fatal consequences of physical fighting, most animals employ mechanisms of conflict resolution involving signalling and ritualistic assessment. Here we provide the first evidence of ubiquitous escalated fighting in grasshoppers. The chameleon grasshopper (Kosciuscola tristis) is an Australian alpine specialist, in which males engage in highly aggressive combat over ovipositing females. We describe discrete agonistic behaviours including mandible flaring, mounting, grappling, kicking and biting, and their use depending on the individual’s role as challenger or defender. We show that male role predicts damage, with challengers being more heavily damaged than males defending females (defenders). Challengers also possess wider mandibles than defenders, but are similar in other metrics of body size. Our data suggest that fights escalate between males matched in body size and that mandibles are used as weapons in this species. This system represents an exciting opportunity for future research into the evolution of costly fighting behaviour in an otherwise placid group. PMID:23166725

  10. [Applications of spectral analysis technique to monitoring grasshoppers].

    Science.gov (United States)

    Lu, Hui; Han, Jian-guo; Zhang, Lu-da

    2008-12-01

    Grasshopper monitoring is of great significance in protecting environment and reducing economic loss. However, how to predict grasshoppers accurately and effectively is a difficult problem for a long time. In the present paper, the importance of forecasting grasshoppers and its habitat is expounded, and the development in monitoring grasshopper populations and the common arithmetic of spectral analysis technique are illustrated. Meanwhile, the traditional methods are compared with the spectral technology. Remote sensing has been applied in monitoring the living, growing and breeding habitats of grasshopper population, and can be used to develop a forecast model combined with GIS. The NDVI values can be analyzed throughout the remote sensing data and be used in grasshopper forecasting. Hyper-spectra remote sensing technique which can be used to monitor grasshoppers more exactly has advantages in measuring the damage degree and classifying damage areas of grasshoppers, so it can be adopted to monitor the spatial distribution dynamic of rangeland grasshopper population. Differentialsmoothing can be used to reflect the relations between the characteristic parameters of hyper-spectra and leaf area index (LAI), and indicate the intensity of grasshopper damage. The technology of near infrared reflectance spectroscopy has been employed in judging grasshopper species, examining species occurrences and monitoring hatching places by measuring humidity and nutrient of soil, and can be used to investigate and observe grasshoppers in sample research. According to this paper, it is concluded that the spectral analysis technique could be used as a quick and exact tool in monitoring and forecasting the infestation of grasshoppers, and will become an important means in such kind of research for their advantages in determining spatial orientation, information extracting and processing. With the rapid development of spectral analysis methodology, the goal of sustainable monitoring

  11. Abundance and guild structure of grasshoppers (Orthoptera ...

    African Journals Online (AJOL)

    The lightly grazed area, characterised by tall vegetation and high aerial cover, low greenness of grass, and low frequency of forbs, was inhabited by grasshopper species associated with long and/or thick grass, that were mixed feeders or tough grass feeders. The mowed area, characterised by short vegetation and low ...

  12. Sublethal toxicity and biotransformation of pyrene in Lumbriculus variegatus (Oligochaeta)

    International Nuclear Information System (INIS)

    Maeenpaeae, K.; Leppaenen, M.T.; Kukkonen, J.V.K.

    2009-01-01

    The aim of this work was to study the toxicity and biotransformation of polyaromatic hydrocarbon (PAH) pyrene in the oligochaete aquatic worm, Lumbriculus variegatus. PAHs are ubiquitous environmental pollutants that pose a hazard to aquatic organisms, and metabolizing capability is poorly known in the case of many invertebrate species. To study the toxicity and biotransformation of pyrene, the worm was exposed for 15 days to various concentrations of water-borne pyrene. The dorsal blood vessel pulse rate was used as a sublethal endpoint. Pyrene biotransformation by L. variegatus was studied and the critical body residues (CBR) were estimated for pyrene toxicity. The toxicokinetics of pyrene uptake was evaluated. A combination of radiolabeled ( 14 C) and nonlabeled pyrene was used in the exposures, and liquid scintillation counting (LSC) and high-pressure liquid chromatography were employed in both water and tissue residue analyses. The results showed that L. variegatus was moderately able to metabolize pyrene to 1-hydroxypyrene (1-HP), thus demonstrating that the phase-I-like oxidizing enzyme system metabolizes pyrene in L. variegatus. The amount of the 1-HP was 1-2% of the amount of pyrene in the worm tissues. The exposure to pyrene reduced the blood vessel pulse rate significantly (p < 0.05), showing that pyrene had a narcotic effect. The estimated CBRs remained constant during the exposure time, varying from 0.120 to 0.174 mmol pyrene/kg worm wet weight. The bioconcentration factors (BCF) decreased as exposure concentration increased. It was suggested that the increased toxicity of pyrene accounted for the decrease in BCFs by lowering the activity of the organism

  13. Patterns of vegetation and grasshopper community composition.

    Science.gov (United States)

    Kemp, W P; Harvey, S J; O'Neill, K M

    1990-06-01

    A study was conducted to evaluate differences in rangeland grasshopper communities over environmental gradients in Gallatin Valley, Montana, USA. The concept of habitat type (Daubenmire 1966) was used as a basis for discriminating between groupings of patches based on vegetation. A total of 39 patches were selected that represented five recognized grassland habitat types (Mueggler and Stewart 1980), as well as two disturbed types (replanting within a known habitat type). Repeated sampling in 1988 of both the insect and plant communities yielded a total of 40 grasshopper (19 664 individuals) and 97 plant species. Detrended Correspondence Analysis (DCA) indicated that patch classifications based on presence and percent cover of plants were appropriate and showed good between-group (habitat type) separation for patches along gradients of precipitation/elevation and plant community complexity. Results from undisturbed habitats showed that plant and grasshopper species composition changed over observed environmental gradients and suggested that habitat type influenced not only species presence, but also relative abundance. Discussion is presented that relates results with patch-use and core and satellite species paradigms.

  14. Morphological aspects of placenta of the Bradypus variegatus Shinz, 1825

    OpenAIRE

    Amorin, Marleyne José Afonso Accyoli Lins; Miglino, Maria Angélica; Amorin Júnior, Adelmar Afonso; Santos, Tatiana Carlesso dos

    2003-01-01

    Estudaram-se os aspectos morfológicos da placenta e das membranas fetais de 03 placentas de bichos-preguiça (Bradypus variegatus), adultas e prenhes, originárias da Zona da Mata do Estado de Pernambuco. Essas estruturas foram obtidas de 03 fêmeas doadas pela Universidade Federal de Pernambuco, das quais duas encontravam-se congeladas e a terceira foi colhida mediante realização de cirurgia cesariana, onde mãe e feto foram preservados. Depois de descongeladas, as placentas foram fixadas em sol...

  15. Variable effects of dipteran parasitoids and management treatment on grasshopper fecundity in a tallgrass prairie.

    Science.gov (United States)

    Laws, A N; Joern, A

    2012-04-01

    Grasshoppers host a number of parasitoids, but little is known about their impact on grasshopper life history attributes or how those impacts may vary with land use. Here, we report on a three-year survey of nine grasshopper species in a tallgrass prairie managed with fire and bison grazing treatments. We measured parasitoid prevalence and the impact of parasitoid infection on grasshopper fecundity to determine if grasshopper-parasitoid interactions varied with management treatment. Adult female grasshoppers were collected every three weeks from eight watersheds managed with different prescribed burning and grazing treatments. Grasshopper fecundity with and without parasitoids was estimated through dissections of reproductive tracts. Dipteran parasitoids from two families (Nemestrinidae and Tachinidae) were observed infecting grasshoppers. We found significant effects of grazing treatment, but not burn interval, on grasshopper-parasitoid interactions. Parasitoids were three times more abundant in watersheds with bison grazing than in ungrazed watersheds, and the relative abundance of nemestrinid and tachinid flies varied with grazing treatment. Parasitoid prevalence varied among grasshopper species from grasshopper fecundity, with stronger effects on current reproduction than on past reproduction. Furthermore, current fecundity in parasitized grasshoppers was lower in grazed watersheds compared to ungrazed watersheds. Nemestrinid parasitoids generally had stronger impacts on grasshopper fecundity than tachinid parasitoids, the effects of which were more variable.

  16. Nymphal RNAi: systemic RNAi mediated gene knockdown in juvenile grasshopper

    Directory of Open Access Journals (Sweden)

    Dong Ying

    2005-10-01

    Full Text Available Abstract Background Grasshopper serves as important model system in neuroscience, development and evolution. Representatives of this primitive insect group are also highly relevant targets of pest control efforts. Unfortunately, the lack of genetics or gene specific molecular manipulation imposes major limitations to the study of grasshopper biology. Results We investigated whether juvenile instars of the grasshopper species Schistocerca americana are conducive to gene silencing via the systemic RNAi pathway. Injection of dsRNA corresponding to the eye colour gene vermilion into first instar nymphs triggered suppression of ommochrome formation in the eye lasting through two instars equivalent to 10–14 days in absolute time. QRT-PCR analysis revealed a two fold decrease of target transcript levels in affected animals. Control injections of EGFP dsRNA did not result in detectable phenotypic changes. RT-PCR and in situ hybridization detected ubiquitous expression of the grasshopper homolog of the dsRNA channel protein gene sid-1 in embryos, nymphs and adults. Conclusion Our results demonstrate that systemic dsRNA application elicits specific and long-term gene silencing in juvenile grasshopper instars. The conservation of systemic RNAi in the grasshopper suggests that this pathway can be exploited for gene specific manipulation of juvenile and adult instars in a wide range of primitive insects.

  17. Evaluation of PCB bioaccumulation by Lumbriculus variegatus in field-collected sediments

    Science.gov (United States)

    Sediment bioaccumulation tests with Lumbriculus variegatus were performed on polychlorinated biphenyl (PCBs) contaminated sediment samples from the Hudson, Grasse, and Fox Rivers Superfund sites with concurrent measurement of PCB concentrations in sediment interstitial water. Th...

  18. The tracks of the megaterium. Anatomical comparision between Eremotherium Rusconii and Bradypus Variegatus

    Directory of Open Access Journals (Sweden)

    Ricaurte Viveros

    2004-01-01

    Full Text Available Based on an anatomical comparison between Eremotherium rusconii and Bradypus variegatus and a literature review, similarities and differences between these species were established in an attempt to explain the extinction of E. rusconii. Proportions between femur and humerus, scall, hair, nails and metabolism were compared. Based on this, it appears that B. variegatus survival was related to its smaller size and feeding habits.

  19. Grasshopper Population Ecology: Catastrophe, Criticality, and Critique

    Directory of Open Access Journals (Sweden)

    Dale R. Lockwood

    2008-06-01

    Full Text Available Grasshopper population dynamics are an important part of the North American rangeland ecosystem and an important factor in the economies that derive from the rangeland. Outbreak dynamics have plagued management strategies in the rangeland, and attempts to find simple, linear and mechanistic solutions to both understanding and predicting the dynamics have proved fruitless. These efforts to ground theory in a correspondence with the "real" world, including whether the population dynamics are ultimately density dependent or density independent, have generated abundant heat but little light. We suggest that a pragmatic approach, in which theories are taken to be "tools" rather than competing claims of truth, has greater promise to move ecological research in a constructive direction. Two recent non-linear approaches exploiting the tools of complexity science provide insights relevant to explaining and forecasting population dynamics. Observation and data collection were used to structure models derived from catastrophe theory and self-organized criticality. These models indicate that nonlinear processes are important in the dynamics of the outbreaks. And the conceptual structures of these approaches provide clear, albeit constrained or contingent, implications for pest managers. We show that, although these two frameworks, catastrophe theory and self-organized criticality, are very different, the frequency distributions of time series from both systems result in power law relationships. Further, we show that a simple lattice-based model, similar to SOC but structured on the biology of the grasshoppers gives a spatial time series similar to data over a 50-year span and the frequency distribution is also a power law relationship. This demonstration exemplifies how a "both-and" rather than an "either-or" approach to ecological modeling, in which the useful elements of particular theories or conceptual structures are extracted, may provide a way forward

  20. Oviposition site selection by the grasshoppers Melanoplus borealis and M. sanguinipes (Orthoptera: Acrididae)

    Science.gov (United States)

    Female grasshoppers can affect the fitness of their offspring through their selection of oviposition sites. Successful embryological development depends on suitable temperature and moisture levels, factors which may vary considerably on a fine scale in natural environments where grasshoppers occur. ...

  1. Caution: Reptile pets shuttle grasshopper allergy and asthma into homes.

    Science.gov (United States)

    Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Jensen, Sebastian A F; Robibaro, Bruno; Kinaciyan, Tamar

    2015-01-01

    The numbers of reptiles in homes has at least doubled in the last decade in Europe and the USA. Reptile purchases are increasingly triggered by the attempt to avoid potentially allergenic fur pets like dogs and cats. Consequently, reptiles are today regarded as surrogate pets initiating a closer relationship with the owner than ever previously observed. Reptile pets are mostly fed with insects, especially grasshoppers and/or locusts, which are sources for aggressive airborne allergens, best known from occupational insect breeder allergies. Exposure in homes thus introduces a new form of domestic allergy to grasshoppers and related insects. Accordingly, an 8-year old boy developed severe bronchial hypersensitivity and asthma within 4 months after purchase of a bearded dragon. The reptile was held in the living room and regularly fed with living grasshoppers. In the absence of a serological allergy diagnosis test, an IgE immunoblot on grasshopper extract and prick-to-prick test confirmed specific sensitization to grasshoppers. After 4 years of allergen avoidance, a single respiratory exposure was sufficient to trigger a severe asthma attack again in the patient. Based on literature review and the clinical example we conclude that reptile keeping is associated with introducing potent insect allergens into home environments. Patient interviews during diagnostic procedure should therefore by default include the question about reptile pets in homes.

  2. Canalization of freeze tolerance in an alpine grasshopper.

    Science.gov (United States)

    Hawes, Timothy C

    2015-10-01

    In the Rock and Pillar Range, New Zealand, the alpine grasshopper, Sigaus australis Hutton, survives equilibrium freezing (EF) all-year round. A comparison of freeze tolerance (FT) in grasshoppers over four austral seasons for a 1 year period finds that: (a) the majority (>70%) of the sample population of grasshoppers survive single freeze-stress throughout the year; (b) exposure to increased freeze stress (multiple freeze-stress events) does not lead to a loss of freeze tolerance; and (c) responses to increased freeze stress reveal seasonal tuning of the FT adaptation to environmental temperatures. The Rock and Pillar sample population provides a clear example of the canalization of the FT adaptation. Seasonal variability in the extent of tolerance of multiple freezing events indicates that physiology is modulated to environmental temperatures by phenotypic plasticity - i.e. the FT adaptation is permanent and adjustable. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Field diet of the grasshopper Abracris dilecta Walker (Orthoptera, Acrididae

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    Carlos Frankl Sperber

    1996-01-01

    Full Text Available Abracris dilecta Walker, 1870 (Orthoptera, Acrididae, Ommatolampinae ate leafs of at least 14 plant species, in the families Asteraceae, Lamiaceae, Malvales (Sterculiaceae, Tiliaceae or Malvaceae, Poaceae, Fabaceae, Verbenaceae, Aristolochiaceae, Rubiaceae and Melastomataccae. Elephantopus mollis H.B.K. (Asteraceae and Hyptis suaveolens Poit. (Lamiaceae comprised 50% of the diet. The diet breadth of A. dilecta was compared to that of other 11 grasshopper species of the same sub-family, with rarefaction curves. The number of plant species eaten by A. dilecta was greater than that of nine other grasshopper species of the same sub-family (Rhachicreagra spp. but was lower then two others (Microptylopteryx hebardi Rehn, 1905 and Rhachicreagra astytophallus Jago & Rowell, 1981. This results are discussed in view of the broad geographical range and possession of developed wings by A. dilecta, which contrasts with most Ommatolampinae grasshoppers.

  4. Relationships between Plant Diversity and Grasshopper Diversity and Abundance in the Little Missouri National Grassland

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    David H. Branson

    2011-01-01

    Full Text Available A continuing challenge in orthopteran ecology is to understand what determines grasshopper species diversity at a given site. In this study, the objective was to determine if variation in grasshopper abundance and diversity between 23 sites in western North Dakota (USA could be explained by variation in plant species richness and diversity. In this system with relatively low plant diversity, grasshopper species richness and abundance were not significantly associated with plant species richness in either year. Although a number of significant associations between plant diversity and grasshopper diversity were found through regression analyses, results differed greatly between years indicating that plant species richness and diversity did not lead to strong effects on grasshopper diversity metrics. Plant species richness appears to be too coarse grained to lead to accurate predictions of grasshopper species richness in this system dominated by generalist grasshopper species.

  5. First Jurassic grasshopper (Insecta, Caelifera) from China.

    Science.gov (United States)

    Gu, Jun-Jie; Yue, Yanli; Shi, Fuming; Tian, He; Ren, Dong

    2016-09-20

    Orthoptera is divided into two suborders, the Ensifera (katydids, crickets and mole crickets) and the Caelifera (grasshoppers and pygmy mole crickets). The earliest definitive caeliferans are those found in the Triassic (Bethoux & Ross 2005). The extinct caeliferan families, such as Locustopsidae and Locustavidae, may prove to be stem groups to some of the modern superfamilies (Grimaldi & Engel 2005). Locustopsidae is known from the Late Triassic or Early Jurassic to Late Cretaceous, consisting of two subfamilies (Gorochov et al. 2006). They are recorded from Europe, England, Russia, central Asia, China, Egypt, North America, Brazil and Australia. Up to now, Late Mesozoic fossil deposits of China has been reported plenty taxa of orthopterids, e.g. ensiferans, phasmatodeans, grylloblattids (Cui et al. 2012; Gu et al. 2010; Gu et al. 2012a; Gu et al. 2012b; Ren et al. 2012; Wang et al. 2014); but, with few caeliferans records, only four species, Pseudoacrida costata Lin 1982, Mesolocustopsis sinica Hong 1990, Tachacris stenosis Lin 1977 and T. turgis Lin 1980, were reported from the Early Cretaceous of Ningxia, Shandong, Yunnan and Zhejiang of China.

  6. [Identification of the meiotic events in grasshopper spermatogenesis].

    Science.gov (United States)

    Liu, Meng-Hao; Zhao, Kai-Qiang; Wang, Ya-Dong; Yang, Meng-Ping; Zhao, Ning-Ning; Yang, Da-Xiang

    2012-12-01

    The grasshoppers are ideal materials to study various meiotic stages of spermatogenesis due to their easy availability, fairly large chromosomes, and fewer numbers of chromosomes. It is easy to make temporary squash preparation of grasshopper testes; however, it is usually difficult for the beginners to differentiate between stages of meiosis. In view of this, we demonstrated the method of identification of meiotic stages by chromosome number and chromosome conformation, taking spermatogonial meiosis of Locusta migratoria manilensis as an example. We described briefly the mitosis of spermatogonia and the spermatogenesis of this species as well.

  7. Sludge Reduction by Lumbriculus Variegatus in Ahvaz Wastewater Treatment Plant

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    Tim Hendrickx

    2012-08-01

    Full Text Available Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensivehealth hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm.The effects of changes in dissolved oxygen (DO concentration up to 3 mg/L (run 1 and up to 6 mg/L (run 2 were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. Theaverage sludge reductions were obtained as 33% (run 2 and 32% (run 1 in worm reactor,and 16% (run 1 and 12% (run 2 in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blankconditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing.

  8. Isolasi dan Karakterisasi Parsial Kolagen dari Teripang Gamma (Stichopus variegatus

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    Yusro Nuri Fawzya

    2016-06-01

    Full Text Available Isolasi dan karakterisasi parsial kolagen dari teripang gamma (Stichopus variegatus telah dilakukan. Isolasi dilakukan melalui tiga tahap yaitu preparasi, ekstraksi dan isolasi. Tahap preparasi meliputi tahapan penyiangan, pencucian dan perendaman dalam akuades, dalam alkohol, dalam larutan Tris-HCl dan etilenadiaminatetraasetat  (EDTA dan perendaman dalam larutan natrium hidroksida (NaOH. Ekstraksi dilakukan dengan perendaman asam asetat 0,5M. Isolasi dilakukan dengan cara pengendapan menggunakan NaCl dilanjutkan proses dialisis. Isolat kolagen teripang gamma yang diperoleh memiliki rendemen sebesar 16,40% (bobot kering, nilai pH 6,08 dan derajat putih 77,02%. Gugus fungsi kolagen terdiri dari amida A (3412 cm-1, B (2929 cm-1, I (1654 cm-1, II (1554 cm-1, dan III (1239 cm-1. Asam amino utama penyusun kolagen yaitu glisin, prolin, dan alanin, masing-masing sebesar 16,88%; 6,71%; dan 6,42%. Kolagen yang dihasilkan merupakan kolagen tipe I, diduga terdiri dari 3 rantai a1 yang homolog dengan berat molekul 130,33 kDa.

  9. A casual cantharophily: The meeting between Astylus variegatus (Coleoptera: Myleridae and Oxypetalum banksii (Apocynaceae: Asclepiadoideae

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    Fonseca, Rúbia

    2011-08-01

    Full Text Available Cantharophily is reported for the first time in a Brazilian asclepiad, involving the mylerid Astylus variegatus and the nectariferous flowers of Oxypetalum banksii, a plant mainly pollinated by wasps. The use of nectar as food by A. variegatus, considered pollinivorous and granivorous, is also novel. The mutual interaction described here is an example of a plant-pollinator interaction with generalist insects visiting a plant with a specialized pollination system. It’s also temporary and occasional and, therefore, is often overlooked in studies of plant-pollinator interactions. In this study, we found that the casual meeting between O. banksii and A. variegatus was a key event for the reproduction of both.

  10. Mesoherbivores affect grasshopper communities in a megaherbivore-dominated South African savannah.

    Science.gov (United States)

    van der Plas, Fons; Olff, Han

    2014-06-01

    African savannahs are among the few places on earth where diverse communities of mega- and meso-sized ungulate grazers dominate ecosystem functioning. Less conspicuous, but even more diverse, are the communities of herbivorous insects such as grasshoppers, which share the same food. Various studies investigated the community assembly of these groups separately, but it is poorly known how ungulate communities shape grasshopper communities. Here, we investigated how ungulate species of different body size alter grasshopper communities in a South African savannah. White rhino is the most abundant vertebrate herbivore in our study site. Other common mesoherbivores include buffalo, zebra and impala. We hypothesized that white rhinos would have greater impact than mesoherbivores on grasshopper communities. Using 10-year-old exclosures, at eight sites we compared the effects of ungulates on grasshopper communities in three nested treatments: (i) unfenced plots ('control plots') with all vertebrate herbivores present, (ii) plots with a low cable fence, excluding white rhino ('megaherbivore exclosures'), and (iii) plots with tall fences, excluding all herbivores larger than rodents ('complete ungulate exclosures'). In each plot, we collected data of vegetation structure, grass and grasshopper community composition. Complete ungulate exclosures contained 30% taller vegetation than megaherbivore exclosures and they were dominated by different grass and grasshopper species. Grasshoppers in complete ungulate exclosures were on average 3.5 mm longer than grasshoppers in megaherbivore exclosures, possibly due to changes in plant communities or vegetation structure. We conclude that surprisingly, in this megaherbivore hotspot, mesoherbivores, instead of megaherbivores, most strongly affect grasshopper communities.

  11. Breeding biology and nestling development of the Grasshopper Buzzard

    NARCIS (Netherlands)

    Buij, R.; Kortekaas, K.; Folkertsma, I.; Velde, van der M.; Komdeur, J.; Iongh, de H.H.

    2012-01-01

    Research into the effect of environmental variables on reproductive success of tropical raptors is often constrained by the lack of information on breeding biology. We provide the first detailed information of the breeding biology and nestling development of the Grasshopper Buzzard Butastur

  12. Modifications to improve entrance slit thermal stability for grasshopper monochromators

    Science.gov (United States)

    Wallace, Daniel J.; Rogers, Gregory C.; Crossley, Sherry L.

    1994-08-01

    As new monochromators are designed for high-flux storage rings, computer modeling and thermal engineering can be done to process increased heat loads and achieve mechanical stability. Several older monochromators, such as the Mark 2 and Mark 5 Grasshopper monochromators, which were designed in 1974, have thermal instabilities in their entrance slit mechanisms. The Grasshoppers operating with narrow slits experience closure of the entrance slit from thermal expansion. In extreme cases, the thermal expansion of the precision components has caused permanent mechanical damage, leaving the slit uncalibrated and/or inoperable. For the Mark 2 and Mark 5 Grasshopper monochromators at the Synchrotron Radiation Center, the original 440 stainless steel entrance slit jaws were retrofitted with an Invar (low expansion Fe, Ni alloy) slit jaw. To transfer the heat from the critical components, two flexible heat straps of Cu were attached. These changes allow safe operation with a 10 μm entrance slit width where the previous limit was 30 μm. After an initial 2 min equilibration, the slit remains stable to 10%, with 100 mA of beam current. Additional improvements in slit thermal stability are planned for a third Grasshopper.

  13. A comparison of the grasshopper fauna ( Orthoptera: Acridoidea ...

    African Journals Online (AJOL)

    The grasshopper fauna of the Uluguru Mountains and the East Usambara Mountains is compared. There is a marked relationship between habitat and similarity in species composition. The faunal similarity between sites rises with distance from the forest, evidently because the savannah species are widespread species ...

  14. The diversity of caeliferins in American grasshoppers, what possible function?

    Science.gov (United States)

    Caeliferins is a new class of compounds recently identified from regurgitant of the American grasshopper (Schistocerca americana)1. Two closely related caeliferins were shown to induce the release of volatiles in corn plants comparable to what earlier has been shown with volicitin and other fatty a...

  15. chromosome study of some grasshopper species from different

    African Journals Online (AJOL)

    Admin

    College of Natural Sciences, Addis Ababa University, 2012 ... ABSTRACT: Around 200 grasshopper species have been identified in ... degree of karyotypic conservatism. ... This leaves a gap in further molecular studies of .... various minor differences observed are briefly ... chromosome are of about equal size with only.

  16. LIFE-CYCLE TOXICITY OF BIS(TRIBUTYLTIN) OXIDE TO THE SHEEPSHEAD MINNOW (CYPRINODON VARIEGATUS)

    Science.gov (United States)

    The effects of tributyltin (TBT) to the life cycle of the estuarine fish C yprinodon variegatus were examined in a 180-day flow-through exposure. The study was initiated with embryos less than 24 h postfertilization and monitored through hatch, maturation, growth, and reproductio...

  17. Effects of terbutryn on aufwuchs and Lumbriculus variegatus in artificial indoor streams.

    Science.gov (United States)

    Brust, K; Licht, O; Hultsch, V; Jungmann, D; Nagel, R

    2001-09-01

    The effects of the herbicide terbutryn on a simple lotic food web were investigated during a 72-d exposure period in five artificial indoor streams in a greenhouse. The model compound terbutryn, an s-triazine and an inhibitor of photosynthesis, was applied once in each stream at nominal concentrations of 0.6, 6, 60, or 600 microg/L. Terbutryn concentrations in the water were analyzed by gas chromatography/mass spectrometry, and an overall time to 50% dissipation (DT50) of 28 d was calculated. The development of aufwuchs and the population growth and development of the oligochaete Lumbriculus variegatus were investigated. We determined that terbutryn was toxic to L. variegatus at 23.7 mg/L (96-h median lethal concentration [LC50]) and 16.5 mg/L (96-h median effective concentration [EC50]) in static acute toxicity tests. Terbutryn decreased aufwuchs production at 0.6 microg/L in the experimental streams. Population growth of L. variegatus was decreased by 50% at 6 microg/L. The effect of terbutryn on the aufwuchs was a direct effect of decreases in the periphyton. However, the effects on L. variegatus were an indirect effect of terbutryn as a consequence of decrease in the aufwuchs food source and occurred at three-orders-of-magnitude-lower concentrations of terbutryn than the acute toxicity effects. Our study demonstrates the utility of indoor lotic microcosm studies for evaluating both direct and indirect effects of contaminants on aquatic ecosystems.

  18. Grasshopper fecundity responses to grazing and fire in a tallgrass prairie.

    Science.gov (United States)

    Laws, Angela N; Joern, Anthony

    2011-10-01

    Grasshopper abundance and diversity vary with management practices such as fire and grazing. Understanding how grasshopper life history traits such as fecundity respond to management practices is key to predicting grasshopper population dynamics in heterogeneous environments. Landscape-level experimental fire and bison grazing treatments at the Konza Prairie Biological Station (Manhattan, KS) provide an opportunity to examine how management affects grasshopper fecundity. Here we report on grasshopper fecundity for nine common species at Konza Prairie. From 2007 to 2009, adult female grasshoppers were collected every 3 wk from eight watersheds that varied in fire and grazing treatments. Fecundity was measured by examining female reproductive tracts, which contain a record of past and current reproductive activity. Body size was a poor predictor of fecundity for all species. Despite large differences in vegetation structure and composition with management regime (grazing and fire interval), we observed little effect of management on grasshopper fecundity. Habitat characteristics (grasshopper density, vegetation biomass, and vegetation quality; measured in 2008 and 2009) were better predictors of past fecundity than current fecundity, with species-specific responses. Fecundity increased throughout the summer, indicating that grasshoppers were able to acquire sufficient nutritional resources for egg production in the early fall when vegetation quality is generally low. Because fecundity did not vary across management treatments, population stage structure may be more important for determining population level reproduction than management regime at Konza Prairie.

  19. Populations of the northern grasshopper, Melanoplus borealis (Orthoptera: Acrididae), in Alaska are rarely food limited.

    Science.gov (United States)

    Fielding, Dennis J; Zhang, Mingchu

    2011-06-01

    In some systems, grasshoppers appear to be food limited in most years, whereas in other systems top down forces, for example, predators, are more often implicated in population regulation. Sustainable strategies to manage grasshopper populations through habitat management require knowledge of the forces that regulate grasshopper populations. This experiment was undertaken to determine whether populations of Melanoplus borealis (Fieber), a common pest species in Alaska, are food-limited in Alaska. Cages were set up in a fallow field near Delta Junction, AK, in 3 yr (2007-2009). In 2007 and 2008, fertilizer was added to half the plots to increase primary production, and, in all years, cages within each plot were stocked with 0, 5, 9, or 13 fourth-instar M. borealis (equivalent to 0, 20, 36, or 52 grasshoppers/m(2)). Grasshoppers in each cage were counted weekly. Near the end of the growing season, surviving female grasshoppers (≈40% of the original number) were collected. Femur length was taken as a measure of adult size, and functional ovarioles were counted as a measure of current fecundity. If the grasshoppers were food limited, we expected to see significant effects of either density or fertilizer on grasshopper survival, size, or fecundity. The fertilizer treatment greatly increased primary production in both years. Neither fertilizer treatment nor grasshopper density had consistent effects on survival, size, or potential fecundity, leading us to conclude that food is seldom limiting to populations in the interior of Alaska at densities <50 m(-2).

  20. Allocation of Nutrients to Somatic Tissues in Young Ovariectomized Grasshoppers

    Science.gov (United States)

    Judd, Evan T.; Hatle, John D.; Drewry, Michelle D.; Wessels, Frank J.; Hahn, Daniel A.

    2010-01-01

    The disposable soma hypothesis predicts that when reproduction is reduced, life span is increased because more nutrients are invested in the soma, increasing somatic repair. Rigorously testing the hypothesis requires tracking nutrients from ingestion to allocation to the soma or to reproduction. Fruit flies on life-extending dietary restriction increase allocation to the soma “relative” to reproduction, suggesting that allocation of nutrients can be associated with extension of life span. Here, we use stable isotopes to track ingested nutrients in ovariectomized grasshoppers during the first oviposition cycle. Previous work has shown that ovariectomy extends life span, but investment of protein in reproduction is not reduced until after the first clutch of eggs is laid. Because ovariectomy does not affect investment in reproduction at this age, the disposable soma hypothesis would predict that ovariectomy should also not affect investment in somatic tissues. We developed grasshopper diets with distinct signatures of 13C and 15N, but that produced equivalent reproductive outputs. These diets are, therefore, appropriate for the reciprocal switches in diet needed for tracking ingested nutrients. Incorporation of stable isotopes into eggs showed that grasshoppers are income breeders, especially for carbon. Allocation to the fat body of nitrogen ingested as adults was slightly increased by ovariectomy; this was our only result that was not consistent with the disposable soma hypothesis. In contrast, ovariectomy did not affect allocation of nitrogen to femoral muscles. Further, allocation of carbon to the fat body or femoral muscles did not appear to be affected by ovariectomy. Total anti-oxidant activities in the hemolymph and femoral muscles were not affected by ovariectomy. These experiments showed that allocation of nutrients was altered little by ovariectomy in young grasshoppers. Additional studies on older individuals are needed to further test the disposable

  1. Genomic gigantism: DNA loss is slow in mountain grasshoppers.

    Science.gov (United States)

    Bensasson, D; Petrov, D A; Zhang, D X; Hartl, D L; Hewitt, G M

    2001-02-01

    Several studies have shown DNA loss to be inversely correlated with genome size in animals. These studies include a comparison between Drosophila and the cricket, Laupala, but there has been no assessment of DNA loss in insects with very large genomes. Podisma pedestris, the brown mountain grasshopper, has a genome over 100 times as large as that of Drosophila and 10 times as large as that of Laupala. We used 58 paralogous nuclear pseudogenes of mitochondrial origin to study the characteristics of insertion, deletion, and point substitution in P. pedestris and Italopodisma. In animals, these pseudogenes are "dead on arrival"; they are abundant in many different eukaryotes, and their mitochondrial origin simplifies the identification of point substitutions accumulated in nuclear pseudogene lineages. There appears to be a mononucleotide repeat within the 643-bp pseudogene sequence studied that acts as a strong hot spot for insertions or deletions (indels). Because the data for other insect species did not contain such an unusual region, hot spots were excluded from species comparisons. The rate of DNA loss relative to point substitution appears to be considerably and significantly lower in the grasshoppers studied than in Drosophila or Laupala. This suggests that the inverse correlation between genome size and the rate of DNA loss can be extended to comparisons between insects with large or gigantic genomes (i.e., Laupala and Podisma). The low rate of DNA loss implies that in grasshoppers, the accumulation of point mutations is a more potent force for obscuring ancient pseudogenes than their loss through indel accumulation, whereas the reverse is true for Drosophila. The main factor contributing to the difference in the rates of DNA loss estimated for grasshoppers, crickets, and Drosophila appears to be deletion size. Large deletions are relatively rare in Podisma and Italopodisma.

  2. Micro-Evolution in Grasshoppers Mediated by Polymorphic Robertsonian Translocations

    Science.gov (United States)

    Colombo, Pablo C.

    2013-01-01

    This review focuses on grasshoppers that are polymorphic for Robertsonian translocations because in these organisms the clarity of meiotic figures allows the study of both chiasma distribution and the orientation of trivalents and multivalents in metaphase I. Only five species of such grasshoppers were found in the literature, and all of them were from the New World: Oedaleonotus enigma (Scudder) (Orthoptera: Acrididae), Leptysma argentina Bruner, Dichroplus pratensis Bruner, Sinipta dalmani Stål, and Cornops aquaticum Bruner. A general feature of these species (except O. enigma) is that fusion carriers suffer a marked reduction of proximal and interstitial (with respect to the centromere) chiasma frequency; this fact, along with the reduction in the number of linkage groups with the consequent loss of independent segregation, produces a marked decrease of recombination in fusion carriers. This reduction in recombination has led to the conclusion that Robertsonian polymorphic grasshopper species share some properties with inversion polymorphic species of Drosophila, such as the central-marginal pattern (marginal populations are monomorphic, central populations are highly polymorphic). This pattern might be present in D. pratensis, which is certainly the most complex Robertsonian polymorphism system in the present study. However, L. argentina and C. aquaticum do not display this pattern. This issue is open to further research. Since C. aquaticum is soon to be released in South Africa as a biological control, the latitudinal pattern found in South America may repeat there. This experiment's outcome is open and deserves to be followed. PMID:23909914

  3. Chemical cues from females trigger male courtship behaviour in grasshoppers.

    Science.gov (United States)

    Finck, Jonas; Kuntze, Janine; Ronacher, Bernhard

    2016-05-01

    Gomphocerine grasshoppers use species-specific calling songs for sex recognition and mate attraction. In two closely related species, Chorthippus biguttulus and C. mollis, acoustic communication is the only experimentally characterized communication channel that elicits male courtship behaviour. However, courtship in these species involves extensive close-range interactions that are likely to be mediated by other signalling modalities, in particular chemical cues. We developed a bioassay to determine if female cuticular hydrocarbons (CHCs) act as chemical cues that induce courtship behaviour, and if males assess variation in CHCs to determine whether or not to court a female. The results of this approach provide evidence that grasshopper males use species- and sex-specific information from CHC signals and respond with a courtship song to the CHC profile of conspecific females but not to the CHC profile of heterospecific females and conspecific males. We conclude that males of C. biguttulus and C. mollis use multimodal channels for mating decisions, based on both acoustic and olfactory cues. We discuss various factors that might favour the evolution of male choosiness in grasshoppers.

  4. Spatial autocorrelation in farmland grasshopper assemblages (Orthoptera: Acrididae) in western France.

    Science.gov (United States)

    Badenhausser, I; Gouat, M; Goarant, A; Cornulier, T; Bretagnolle, V

    2012-10-01

    Agricultural intensification in western Europe has caused a dramatic loss of grassland surfaces in farmlands, which have resulted in strong declines in grassland invertebrates, leading to cascade effects at higher trophic levels among consumers of invertebrates. Grasshoppers are important components of grassland invertebrate assemblages in European agricultural ecosystems, particularly as prey for bird species. Understanding how grasshopper populations are distributed in fragmented landscapes with low grassland availability is critical for both studies in biodiversity conservation and insect management. We assessed the range and strength of spatial autocorrelation for two grasshopper taxa (Gomphocerinae subfamily and Calliptamus italicus L.) across an intensive farmland in western France. Data from surveys carried out over 8 yr in 1,715 grassland fields were analyzed using geostatistics. Weak spatial patterns were observed at small spatial scales, suggesting important local effects of management practices on grasshopper densities. Spatial autocorrelation patterns for both grasshopper taxa were only detected at intermediate scales. For Gomphocerinae, the range of spatial autocorrelation varied from 802 to 2,613 m according to the year, depending both on grasshopper density and on grassland surfaces in the study site, whereas spatial patterns for the Italian locust were more variable and not related to grasshopper density or grassland surfaces. Spatial patterns in the distribution of Gomphocerinae supported our hypothesis that habitat availability was a major driver of grasshopper distribution in the landscape, and suggested it was related to density-dependent processes such as dispersal.

  5. Effects of nymph-overwintering grasshopper density on Ageneotettix deorum survival in a northern mixed grassland

    Science.gov (United States)

    Although most pest grasshopper species in North America hatch in late spring or early summer, some species hatch in late summer and become adults in late spring. It is not well understood how they impact densities of later developing pest grasshopper species. In an earlier study examining temporall...

  6. Positive interactions between large herbivores and grasshoppers, and their consequences for grassland plant diversity.

    Science.gov (United States)

    Zhong, Zhiwei; Wang, Deli; Zhu, Hui; Wang, Ling; Feng, Chao; Wang, Zhongnan

    2014-04-01

    Although the influence of positive interactions on plant and sessile communities has been well documented, surprisingly little is known about their role in structuring terrestrial animal communities. We evaluated beneficial interactions between two distantly related herbivore taxa, large vertebrate grazers (sheep) and smaller insect grazers (grasshoppers), using a set of field experiments in eastern Eurasian steppe of China. Grazing by large herbivores caused significantly higher grasshopper density, and this pattern persisted until the end of the experiment. Grasshoppers, in turn, increased the foraging time of larger herbivores, but such response occurred only during the peak of growing season (August). These reciprocal interactions were driven by differential herbivore foraging preferences for plant resources; namely, large herbivores preferred Artemisia forbs, whereas grasshoppers preferred Leymus grass. The enhancement of grasshopper density in areas grazed by large herbivores likely resulted from the selective consumption of Artemisia forbs by vertebrate grazers, which may potentially improve the host finding of grasshoppers. Likewise, grasshoppers appeared to benefit large herbivores by decreasing the cover and density of the dominant grass Leymus chinensis, which hampers large herbivores' access to palatable forbs. Moreover, we found that large herbivores grazing alone may significantly decrease plant diversity, yet grasshoppers appeared to mediate such negative effects when they grazed with large herbivores. Our results suggest that the positive, reciprocal interactions in terrestrial herbivore communities may be more prevalent and complex than previously thought.

  7. Effects of livestock grazing on grasshopper abundance on a native rangeland in Montana.

    Science.gov (United States)

    O'Neill, Kevin M; Olson, Bret E; Wallander, Roseann; Rolston, Marni G; Seibert, Catherine E

    2010-06-01

    Livestock grazing can affect habitat quality for grasshoppers through effects on food and oviposition site availability, microclimate, and other factors. Because of this, some authors have suggested that grazing programs can be used to help manage pest grasshopper populations. In a 6-yr study, we controlled access of cattle to replicated experimental plots on an Agropyron spicatum/Poa sandbergii pasture to create consistent year-to-year differences in postgrazing plant cover, with resultant affects on microclimate. After sampling grasshoppers multiple times after grazing treatments each summer, we found evidence of between-treatment differences in grasshopper abundance for the entire assemblage during 4 of the 6 yr. Some species, including Melanoplus sanguinipes (perhaps the worse rangeland grasshopper pest in the western United States), tended to be more abundant on ungrazed plots, whereas Melanoplus gladstoni often had greater densities on heavily-grazed plots. The effect of grazing on grasshopper densities in this study was lower in magnitude and less consistent among years than in a study we conducted simultaneously at a nearby site where the vegetation was dominated by the exotic species crested wheatgrass (Agropyron cristatum). Our results generally support proposals that grazing could be used to reduce pest grasshopper densities, although the effectiveness of a particular grazing scheme may vary among sites, years, and grasshopper and vegetation assemblages.

  8. Acquisition of nonspecific Bartonella strains by the northern grasshopper mouse (Onychomys leucogaster)

    Science.gov (United States)

    Bai, Y.; Kosoy, M.Y.; Cully, J.F.; Bala, T.; Ray, C.; Collinge, S.K.

    2007-01-01

    Rodent-associated Bartonella species are generally host-specific parasites in North America. Here evidence that Bartonella species can 'jump' between host species is presented. Northern grasshopper mice and other rodents were trapped in the western USA. A study of Bartonella infection in grasshopper mice demonstrated a high prevalence that varied from 25% to 90% by location. Bartonella infection was detected in other rodent species with a high prevalence as well. Sequence analyses of gltA identified 29 Bartonella variants in rodents, 10 of which were obtained from grasshopper mice. Among these 10, only six variants were specific to grasshopper mice, whereas four were identical to variants specific to deer mice or 13-lined ground squirrels. Fourteen of 90 sequenced isolates obtained from grasshopper mice were strains found more commonly in other rodent species and were apparently acquired from these animals. The ecological behavior of grasshopper mice may explain the occurrence of Bartonella strains in occasional hosts. The observed rate at which Bartonella jumps from a donor host species to the grasshopper mouse was directly proportional to a metric of donor host density and to the prevalence of Bartonella in the donor host, and inversely proportional to the same parameters for the grasshopper mouse. ?? 2007 Federation of European Microbiological Societies.

  9. Relationships between plant diversity and grasshopper diversity and abundance in the Little Missouri National Grassland

    Science.gov (United States)

    A continuing challenge in Orthoptera ecology is to understand what determines grasshopper species diversity at a given site. In this study, the objective was to determine if variation in grasshopper abundance and diversity between 23 sites in western North Dakota (USA) could be explained by variatio...

  10. Grasshopper responses to fire and postfire grazing in the northern Great Plains vary among species

    Science.gov (United States)

    Rangeland management practices such as burning and grazing management may affect grasshopper populations by impacting development, survival and reproduction. Experiments are lacking in the northern Great Plains examining the effects of fire and grazing intensity on grasshoppers. As part of a larger ...

  11. Diet influences rates of carbon and nitrogen mineralization from decomposing grasshopper frass and cadavers

    Science.gov (United States)

    Insect herbivory can produce a pulse of mineral nitrogen (N) in soil from the decomposition of frass and cadavers. In this study we examined how diet quality affects rates of N and carbon (C) mineralization from grasshopper frass and cadavers. Frass was collected from grasshoppers fed natural or mer...

  12. Infection of Melanoplus sanguinipes Grasshoppers following Ingestion of Rangeland Plant Species Harboring Vesicular Stomatitis Virus▿

    Science.gov (United States)

    Drolet, Barbara S.; Stuart, Melissa A.; Derner, Justin D.

    2009-01-01

    Knowledge of the many mechanisms of vesicular stomatitis virus (VSV) transmission is critical for understanding of the epidemiology of sporadic disease outbreaks in the western United States. Migratory grasshoppers [Melanoplus sanguinipes (Fabricius)] have been implicated as reservoirs and mechanical vectors of VSV. The grasshopper-cattle-grasshopper transmission cycle is based on the assumptions that (i) virus shed from clinically infected animals would contaminate pasture plants and remain infectious on plant surfaces and (ii) grasshoppers would become infected by eating the virus-contaminated plants. Our objectives were to determine the stability of VSV on common plant species of U.S. Northern Plains rangelands and to assess the potential of these plant species as a source of virus for grasshoppers. Fourteen plant species were exposed to VSV and assayed for infectious virus over time (0 to 24 h). The frequency of viable virus recovery at 24 h postexposure was as high as 73%. The two most common plant species in Northern Plains rangelands (western wheatgrass [Pascopyrum smithii] and needle and thread [Hesperostipa comata]) were fed to groups of grasshoppers. At 3 weeks postfeeding, the grasshopper infection rate was 44 to 50%. Exposure of VSV to a commonly used grasshopper pesticide resulted in complete viral inactivation. This is the first report demonstrating the stability of VSV on rangeland plant surfaces, and it suggests that a significant window of opportunity exists for grasshoppers to ingest VSV from contaminated plants. The use of grasshopper pesticides on pastures would decrease the incidence of a virus-amplifying mechanical vector and might also decontaminate pastures, thereby decreasing the inter- and intraherd spread of VSV. PMID:19286779

  13. Infection of Melanoplus sanguinipes grasshoppers following ingestion of rangeland plant species harboring vesicular stomatitis virus.

    Science.gov (United States)

    Drolet, Barbara S; Stuart, Melissa A; Derner, Justin D

    2009-05-01

    Knowledge of the many mechanisms of vesicular stomatitis virus (VSV) transmission is critical for understanding of the epidemiology of sporadic disease outbreaks in the western United States. Migratory grasshoppers [Melanoplus sanguinipes (Fabricius)] have been implicated as reservoirs and mechanical vectors of VSV. The grasshopper-cattle-grasshopper transmission cycle is based on the assumptions that (i) virus shed from clinically infected animals would contaminate pasture plants and remain infectious on plant surfaces and (ii) grasshoppers would become infected by eating the virus-contaminated plants. Our objectives were to determine the stability of VSV on common plant species of U.S. Northern Plains rangelands and to assess the potential of these plant species as a source of virus for grasshoppers. Fourteen plant species were exposed to VSV and assayed for infectious virus over time (0 to 24 h). The frequency of viable virus recovery at 24 h postexposure was as high as 73%. The two most common plant species in Northern Plains rangelands (western wheatgrass [Pascopyrum smithii] and needle and thread [Hesperostipa comata]) were fed to groups of grasshoppers. At 3 weeks postfeeding, the grasshopper infection rate was 44 to 50%. Exposure of VSV to a commonly used grasshopper pesticide resulted in complete viral inactivation. This is the first report demonstrating the stability of VSV on rangeland plant surfaces, and it suggests that a significant window of opportunity exists for grasshoppers to ingest VSV from contaminated plants. The use of grasshopper pesticides on pastures would decrease the incidence of a virus-amplifying mechanical vector and might also decontaminate pastures, thereby decreasing the inter- and intraherd spread of VSV.

  14. Growth, development, and nutritional physiology of grasshoppers from subarctic and temperate regions.

    Science.gov (United States)

    Fielding, Dennis J; Defoliart, Linda S

    2007-01-01

    Despite the importance of developmental rate, growth rate, and size at maturity in the life history of poikliotherms, the trade-offs among these traits and selection pressures involved in the evolution of these traits are not well understood. This study compared these traits in a grasshopper, Melanoplus sanguinipes F. (Orthoptera: Acrididae), from two contrasting geographical regions, subarctic Alaska and temperate Idaho. The growing season in the interior of Alaska is about 80 d shorter than at low-elevation sites in Idaho. We hypothesized that the Alaskan grasshoppers would show more rapid growth and development than grasshoppers from Idaho, at the cost of greater sensitivity to food quality. On a diet of lettuce and wheat bran, grasshoppers from Alaska developed from egg hatch to adult more rapidly than those from Idaho at each of three different temperature regimes. Averaged over all temperature treatments, the weight of the Alaskan grasshoppers was about 5% less than that of the Idaho grasshoppers at the adult molt. Feeding and digestive efficiencies were determined for the final two instars using two meridic diets: one with a high concentration of nutrients and the other with the same formulation but diluted with cellulose. Alaskan grasshoppers again developed more rapidly, weighed less, and had faster growth rates than those from Idaho. Alaskan grasshoppers supported their more rapid growth by increasing postingestive efficiencies; that is, they had higher conversion rates of digested matter to biomass on the high-quality diet, greater assimilation of food on the low-quality diet, and greater efficiency of nitrogen assimilation or retention on both diets. There was no evidence that performance of Alaskan grasshoppers suffered any more than that of the Idaho grasshoppers on the low-quality diet.

  15. Density mediates grasshopper performance in response to temperature manipulation and spider predation in tallgrass prairie.

    Science.gov (United States)

    Laws, A N; Joern, A

    2017-04-01

    Species interactions are often context-dependent, where outcomes require an understanding of influences among multiple biotic and abiotic factors. However, it remains unclear how abiotic factors such as temperature combine with important biotic factors such as density-dependent food limitation and predation to influence species interactions. Using a native grassland - grasshopper - wolf spider model food chain in tallgrass prairie, we conducted a manipulative field experiment to examine how predator-prey interactions respond to manipulations of temperature, grasshopper density, and food chain length. We find that grasshopper performance responses to temperature and predator treatments were density dependent. At high densities, grasshopper survival decreased with increased temperature when no spiders were present. When spiders were present, grasshopper survival was reduced, and this effect was strongest in the cooled treatment. In contrast, grasshopper survival did not vary significantly with spider presence or among temperature treatments at low grasshopper densities. Our results indicate that context-dependent species interactions are common and highlight the importance of understanding how and when key biotic and abiotic factors combine to influence species interactions.

  16. Horizontal transmission of Paranosema locustae (Microsporidia) in grasshopper populations via predatory natural enemies.

    Science.gov (United States)

    Wang-Peng, Shi; Zheng, Xuan; Jia, Wan-Tong; Li, Ao-Mei; Camara, Ibrahima; Chen, Hong-Xing; Tan, Shu-Qian; Liu, Yi-Qing; Ji, Rong

    2018-04-24

    Paranosema locustae Canning, 1953 (Microsporidia) provides effective control of grasshoppers. While horizontal transmission of P. locustae is known to occur, evidence for the mechanisms of such transmission via predatory natural enemies was found. We conducted a three-year laboratory and field study to assess the potential impact of feces both from grasshoppers Locusta migratoria L. and from their natural enemies on the persistence of P. locustae. We found that P. locustae persisted among grasshopper populations in treated areas and in adjacent untreated areas for up to two years, and the density of grasshoppers decreased in both areas. We showed that healthy grasshoppers could be infected by feeding on food contaminated by feces from their natural enemies. Predators of grasshoppers retained a large number of spores acquired from eating grasshoppers infected with P. locustae. Spores in the feces of the main natural enemy, the beetle Pterostichus gebleri Dejean 1828 in treated area showed clear viability. These results demonstrate that predatory natural enemies are important vectors for this microsporidian disease, and suggest that sustainable transmission and continuing population suppression might be achieved by horizontal transmission through natural enemies, which should be maximized to increase the effectiveness of P. locustae. This article is protected by copyright. All rights reserved.

  17. Grasshoppers of the Mascarene Islands: new species and new records (Orthoptera, Caelifera).

    Science.gov (United States)

    Hugel, Sylvain

    2014-12-23

    The grasshopper fauna of Mascarene Islands (Mauritius, Rodrigues and La Réunion), in South Western Indian ocean is examined. Numerous field surveys and examination of museum specimens recorded twenty species of Grasshoppers on the archipelago. Five of them are new records, including a new species: Odontomelus ancestrus n. sp. restricted to Round Island, a 2 km² islet North to Mauritius. Despite intensive searching, five of the non endemic species once recorded on the archipelago have not been recorded again and might correspond to temporary settlements/introductions. A key to Mascarene grasshoppers is given.

  18. Transcriptome profiling of ontogeny in the acridid grasshopper Chorthippus biguttulus.

    Science.gov (United States)

    Berdan, Emma L; Finck, Jonas; Johnston, Paul R; Waurick, Isabelle; Mazzoni, Camila J; Mayer, Frieder

    2017-01-01

    Acridid grasshoppers (Orthoptera:Acrididae) are widely used model organisms for developmental, evolutionary, and neurobiological research. Although there has been recent influx of orthopteran transcriptomic resources, many use pooled ontogenetic stages obscuring information about changes in gene expression during development. Here we developed a de novo transcriptome spanning 7 stages in the life cycle of the acridid grasshopper Chorthippus biguttulus. Samples from different stages encompassing embryonic development through adults were used for transcriptomic profiling, revealing patterns of differential gene expression that highlight processes in the different life stages. These patterns were validated with semi-quantitative RT-PCR. Embryonic development showed a strongly differentiated expression pattern compared to all of the other stages and genes upregulated in this stage were involved in signaling, cellular differentiation, and organ development. Our study is one of the first to examine gene expression during post-embryonic development in a hemimetabolous insect and we found that only the fourth and fifth instars had clusters of genes upregulated during these stages. These genes are involved in various processes ranging from synthesis of biogenic amines to chitin binding. These observations indicate that post-embryonic ontogeny is not a continuous process and that some instars are differentiated. Finally, genes upregulated in the imago were generally involved in aging and immunity. Our study highlights the importance of looking at ontogeny as a whole and indicates promising directions for future research in orthopteran development.

  19. Song variation and environmental auditory masking in the grasshopper sparrow

    Science.gov (United States)

    Lohr, Bernard; Dooling, Robert J.; Gill, Douglas E.

    2004-05-01

    Some grassland bird species, in particular grasshopper sparrows (Ammodramus savannarum), sing songs with especially high mean frequencies (7.0-8.0 kHz). Acoustic interference is one potential explanation for the evolution of high frequency vocalizations, particularly in open habitats. We tested predictions from a model of effective auditory communication distances to understand the potential effects of vocal production and environmental auditory masking on vocal behavior and territoriality. Variation in the spectral structure of songs and the size and shape of territories was measured for grasshopper sparrows in typical grassland habitats. Median territory areas were 1629 m2 at a site in the center of the species range in Nebraska, and 1466 m2 at our study site in Maryland, with average territory diameters measuring 20.2 m. Species densities and sound pressure levels also were determined for stridulating insects and other noise sources in the habitat. Based on current models of effective communication distances, known noise levels, and information on hearing abilities, our results suggest that auditory sensitivity and environmental noise could be factors influencing the mean frequency and spatial dynamics of territorial behavior in grassland birds. [Work supported by NIH and the CRFRC.

  20. Morphological differentiation despite gene flow in an endangered grasshopper.

    Science.gov (United States)

    Dowle, Eddy J; Morgan-Richards, Mary; Trewick, Steven A

    2014-10-16

    Gene flow is traditionally considered a limitation to speciation because selection is required to counter the homogenising effect of allele exchange. Here we report on two sympatric short-horned grasshoppers species in the South Island of New Zealand; one (Sigaus australis) widespread and the other (Sigaus childi) a narrow endemic. Of the 79 putatively neutral markers (mtDNA, microsatellite loci, ITS sequences and RAD-seq SNPs) all but one marker we examined showed extensive allele sharing, and similar or identical allele frequencies in the two species where they co-occur. We found no genetic evidence of deviation from random mating in the region of sympatry. However, analysis of morphological and geometric traits revealed no evidence of morphological introgression. Based on phenotype the two species are clearly distinct, but their genotypes thus far reveal no divergence. The best explanation for this is that some loci associated with the distinguishing morphological characters are under strong selection, but exchange of neutral loci is occurring freely between the two species. Although it is easier to define species as requiring a barrier between them, a dynamic model that accommodates gene flow is a biologically more reasonable explanation for these grasshoppers.

  1. Transferable Antibiotic Resistances in Marketed Edible Grasshoppers (Locusta migratoria migratorioides).

    Science.gov (United States)

    Osimani, Andrea; Garofalo, Cristiana; Aquilanti, Lucia; Milanović, Vesna; Cardinali, Federica; Taccari, Manuela; Pasquini, Marina; Tavoletti, Stefano; Clementi, Francesca

    2017-05-01

    Grasshoppers are the most commonly eaten insects by humans worldwide, as they are rich in proteins and micronutrients. This study aimed to assess the occurrence of transferable antibiotic resistance genes in commercialized edible grasshoppers. To this end, the prevalence of 12 selected genes [aac(6')-Ie aph(2″)-Ia, blaZ, erm(A), erm(B), erm(C), mecA, tet(M), tet(O), tet(S), tet(K), vanA, vanB] coding for resistance to antibiotics conventionally used in clinical practice was determined. The majority of samples were positive for tet(M) (70.0%), tet(K) (83.3%) and blaZ (83.3%). A low percentage of samples were positive for erm(B) (16.7%), erm(C) (26.7%), and aac(6')-Ie aph(2″)-Ia (13.3%), whereas no samples were positive for erm(A), vanA, vanB, tet(O), and mecA. Cluster analysis identified 4 main clusters, allowing a separation of samples on the basis of their country of origin. © 2017 Institute of Food Technologists®.

  2. Phylogenetic Characterization of Encephalitozoon Romaleae (Microsporidia) from a Grasshopper Host: Relationship to Encephalitozoon spp. Infecting Humans

    Science.gov (United States)

    Encephalitozoon species are the most common microsporidian pathogens of humans and domesticated animals. We recently discovered a new microsporidium, Encephalitozoon romaleae, infecting the eastern lubber grasshopper Romalea microptera. To understand its evolutionary relationships, we compared par...

  3. Feeding preference of the sea urchin Lytechinus variegatus (Lamarck, 1816 on seaweeds

    Directory of Open Access Journals (Sweden)

    Camilla Ferreira Souza

    2008-09-01

    Full Text Available Seaweeds exhibit different strategies to minimize the damage caused by herbivores and also to influence the feeding preference of these consumers. This study evaluated the feeding preference of the sea urchin Lytechinus variegatus through multiple-choice experiments using the seaweeds Caulerpa racemosa, Dictyota menstrualis, Osmundaria obtusiloba, Plocamium brasiliense, Sargassum sp., and Ulva sp. In order to verify the importance of morphological and chemical aspects on this feeding preference, two assay-types were carried out using live and powdered macroalgae, respectively. Two different methods were employed to analyze the results obtained: comparison between biomass losses versus autogenic changes, and inclusion of autogenic values in biomass loss through herbivory. In both experiments a clear differential consumption of certain species of seaweeds by L. variegatus was observed, in the following decreasing order of preference: C. racemosa ≈ Ulva sp. > O. obtusiloba ≈ Sargassum sp. > P. brasiliense > D. menstrualis. It was also verified that both methods of analysis used yielded similar results. According to the results obtained, feeding preference of L. variegatus is probably established by the defensive chemicals produced by P. brasiliense and D. menstrualis, and by morphological aspects of C. racemosa, Ulva sp., O. obtusiloba and Sargassum sp.As macroalgas apresentam diversos tipos de estratégias para minimizar os danos gerados por herbívoros que influenciam a preferência alimentar dos consumidores. Este estudo avaliou a preferência alimentar do ouriço-do-mar Lytechinus variegatus em experimentos de múltipla escolha utilizando as macroalgas bentônicas Caulerpa racemosa, Dictyota menstrualis, Osmundaria obtusiloba, Plocamium brasiliense, Sargassum sp., e Ulva sp. Para verificar a importância dos aspectos morfológicos e químicos na preferência, os ensaios foram realizados com algas vivas e em pó, respectivamente. Foram

  4. Distribution of Grasshoppers (Insecta: Orthoptera among different host plants and habitats in two districts of Tamil Nadu, India

    Directory of Open Access Journals (Sweden)

    M.G. Paulraj

    2009-04-01

    Full Text Available In a survey of grasshoppers in nine localities of northeastern Tamil Nadu, carried out from August 2004 to December 2006, 33 grasshopper species grouped under four families were recorded. Family Acrididae was found to be the predominant group of grasshoppers represented by 21 species, which was 63.6% of the total species collected. The acridids collected can be classified under seven subfamilies and 15 genera. Family Tettigoniidae was the second largest group represented by six species falling under five genera and three subfamilies, and this family contributed 18.2% to the total grasshopper species recorded in this study. Among the different habitats, grasses supported the highest number of 18 species (54.6% while 11 species were surface grasshoppers. The painted grasshopper Poekilocerus pictus (Fab. was collected from many plants viz., Calotropis, curry leaf, grass, groundnut, okra, and on ground. The maximum number of species was recorded from Manimangalam in Kancheepuram District during the entire study period.

  5. Alimentación y fecundidad de Bufo variegatus (Anura: Bufonidae en Santa Cruz, Argentina

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    Rappi, Guillermina E.

    2000-04-01

    Full Text Available Se describe la alimentación de una población de Bufo variegatus procedente de la región de Lago del Desierto, provincia de Santa Cruz, Argentina. De los 11 ítems presa identificados, los más consumidos por los adultos (tanto machos como hembras fueron los coleópteros. En los machos la segunda categoría presa mas importante en la contribución a la dieta fueron los ácaros, mientras que en las hembras las hormigas y las larvas de insectos siguieron en importancia al consumo de coleópteros. En los especímenes juveniles, los ácaros fueron las presas más consumidas, quedando los coleópteros en segundo lugar en importancia relativa. Se demuestra la existencia de una correlación positiva significativa entre el volumen de las presas y el tamaño del depredador. Se aportan datos referentes a la fecundidad de B. variegatus y se comprueba la ausencia de correlación entre el tamaño de las hembras grávidas y el número de óvulos maduros. The diet of a population of Bufo variegatus from the region of Lago del Desierto, Santa Cruz province, Argentina, is described. Of the 11 prey items identified, Coleoptera was the most consumed prey both for males and females. In males, the second most important prey was Acarii, while in females they were the ants and insect larvae. Acarii was the most consumed prey for juveniles, followed by Coleoptera. A significant positive correlation was found between prey volume and predator body size. Fecundity information for B. variegwus is given, and a lack of correlation between snout-vent length of mature females and ovarian egg complement is demonstrated.

  6. Tongue papillae morphology of brown-throated sloth Bradypus variegatus (SCHINZ, 1825

    Directory of Open Access Journals (Sweden)

    D.M. Martins

    2014-10-01

    Full Text Available The Bradypus variegatus inhabits the forests of South America and feeds from leaves, branches and sprouts from different plants. Due to its diet and the lack of literature on the morphological aspect of Xenarthras, five Bradypus variegatus tongues from animals which died from natural causes were evaluated, and they came from Pará State Museum Emílio Goeldi and were donated to the Laboratory of Animal Morphological Research (LaPMA from UFRA, for revealing the different types of papillae and epithelial-connective tissue. Macroscopically, the tongues presented elongated shape, rounded apex, body, root, median sulcus in the root's apex, and two vallate papillae. The mucous membrane of the tongue revealed a keratinized stratified pavement epithelium, while the ventral surface of the tongue was thin and smooth, not provided with any type of papillae. However, the dorsal surface of the tongue was irregular with the presence of three types of papillae: filiform, fungiform and vallate papillae. The filiform papillae found were of a simple type, presenting a rounded base, irregularly distributed with a larger concentration and development on the tongue's apex and body. The fungiform papilla showed a practically smooth surface with irregular format, with the presence of gustatory pores; these were found all over the dorsal surface, with larger concentration at the rostral part of the apex. Only two vallate papillae were observed disposed in the root of the tongue, surrounded by a deep groove, and revealing several taste buds. The tongues from Bradypus variegatus presented gustatory papillae similar to the ones described for other Xenarthras species and wild mammals.

  7. Response of barley to grasshopper defoliation in interior Alaska: dry matter and grain yield.

    Science.gov (United States)

    Begna, Sultan H; Fielding, Dennis J

    2005-12-01

    Barley, Hordeum vulgare L., is well adapted to subarctic Alaska growing conditions, but little is known about its response to grasshopper defoliation. A field experiment was conducted to study dry matter and grain yield in response to a combination of grasshopper defoliation and weeds in 2002 and 2003 near Delta Junction, AK (63 degrees 55' N, 145 degrees 20' W). Barley plants at third to fourth leaf stage were exposed to a combination of two levels of weeds (present or absent) and four densities of grasshoppers (equivalent to 0, 25, 50, and 75 grasshoppers per m2) of third to fourth instars of Melanoplus sanguinipes (F). Dry matter accumulation by the barley plants was determined at three times during the growing seasons: approximately 10 d after introduction of the grasshoppers, shortly after anthesis, and at maturity. Dry matter accumulation and grain yield were much lower in 2003 than in 2002, probably due to very low levels of soil moisture early in the growing season of 2003. Head clipping accounted for a greater portion of yield loss in 2003 than in 2002. The percentage of reduction in harvestable yield due to grasshoppers remained fairly constant between years (1.9 and 1.4 g per grasshopper per m2 in 2002 and 2003, respectively) despite a large difference in overall yield. Examination of the yield components suggest that yields were reduced by the early season drought in 2003 primarily through fewer seeds per head, whereas grasshoppers in both years reduced average seed weight, but not numbers of seeds.

  8. Mechanical Vectors Enhance Fungal Entomopathogen Reduction of the Grasshopper Pest Camnula pellucida (Orthoptera: Acrididae).

    Science.gov (United States)

    Kistner, Erica J; Saums, Marielle; Belovsky, Gary E

    2015-02-01

    Mounting scientific evidence indicates that pathogens can regulate insect populations. However, limited dispersal and sensitivity to abiotic conditions often restricts pathogen regulation of host populations. While it is well established that arthropod biological vectors increase pathogen incidence in host populations, few studies have examined whether arthropod mechanical vectors (an organism that transmits pathogens but is not essential to the life cycle of the pathogen) influence host-pathogen dynamics. The importance of mechanical dispersal by ant scavengers, Formica fusca (L.), in a grasshopper-fungal entomopathogen system was investigated. We examined the ability of ants to mechanically disperse and transmit the pathogen, Entomophaga grylli (Fresenius) pathotype 1, to its host, the pest grasshopper Camnula pellucida (Scudder), in a series of laboratory experiments. Fungal spores were dispersed either externally on the ant's body surface or internally through fecal deposition. In addition, a third of all grasshoppers housed with fungal-inoculated ants became infected, indicating that ants can act as mechanical vectors of E. grylli. The effect of ant mechanical vectors on E. grylli incidence was also examined in a field experiment. Ant access to pathogen-exposed experimental grasshopper populations was restricted using organic ant repellent, thereby allowing us to directly compare mechanical and natural transmission. Ants increased grasshopper pathogen mortality by 58%, which led to greater pathogen reductions of grasshopper survival than natural transmission. Taken together, our results indicate that ants enhance E. grylli reduction of grasshopper pest numbers. Therefore, mechanical transmission of pathogens may be an important overlooking component of this grasshopper-fungal pathogen system. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Aspectos morfológicos da placenta da preguiça, Bradypus variegatus Shinz, 1825

    OpenAIRE

    Marleyne José Afonso Accyoli Lins Amorin; Maria Angélica Miglino; Adelmar Afonso Amorin Júnior; Tatiana Carlesso dos Santos

    2003-01-01

    Estudaram-se os aspectos morfológicos da placenta e das membranas fetais de 03 placentas de bichos-preguiça (Bradypus variegatus), adultas e prenhes, originárias da Zona da Mata do Estado de Pernambuco. Essas estruturas foram obtidas de 03 fêmeas doadas pela Universidade Federal de Pernambuco, das quais duas encontravam-se congeladas e a terceira foi colhida mediante realização de cirurgia cesariana, onde mãe e feto foram preservados. Depois de descongeladas, as placentas foram fixadas em sol...

  10. Analysis of Spatial Pattern among Grasshopper and Vegetation in Heihe based on GIS

    Science.gov (United States)

    Zhou, Wei; Wang, KeMing; Zhao, Chengzhang; Zhang, Qi-peng

    Geostatistics was used to analyze the grasshopper and dominant plants population spatial pattern and their relationship in the upper reaches of Heihe River under GIS platform. The results showed that the plants and grasshoppers populations have strong spatial correlation in study area. The Semivariogram curve of Chorthippus brunneus huabeiensis, Filchnerella, Aneurolepidium dasystanchys and Artemisia dalailamae is spherical model, Gomphocerus licenti and Stipa krylovii's Semivariogram curve is exponential and Gaussian model respectively, and their spatial autocorrelation scope is 10.8, 11.3, 11.5, 12.4, 23.5 and 59.7 meters respectively. Stipa krylovii and Artemisia dalailamae spatial distribution was patchy, Aneurolepidium dasystanchys showed flaky distribution; Gomphocerus licenti and Chorthippus brunneus huabeiensis mainly located in southeast areas with high coverage of Stipa krylovii and Aneurolepidium dasystanchys. Filchnerella nearly located in North areas with high coverage of Artemisia dalailamae, but were rarely found in south and east areas. The effects of different plants coverage on grasshopper abundance are significantly different. Filchnerella abundance and Artemisia dalailamae coverage showed significantly positive correlation, Chorthippus brunneus huabeiensis and Gomphocerus licenti positively correlated with Aneurolepidium dasystanchys and Stipa krylovii. Grasshopper spatial patterns and occurrence numbers are both influenced by grasshopper biological characteristics and plant community composition, which reflected complex coupled relation between grasshopper and plant.

  11. Different levels of shade on population of grasshoppers and its oviposition preference on heliconias

    Directory of Open Access Journals (Sweden)

    Ana Cristina Bittar

    2018-02-01

    Full Text Available ABSTRACT: Grasshoppers of the families Acrididae and Romaleidae (Orthoptera are among the insects that defoliate heliconias and have been gaining status as pests of commercial crops of these plants in Brazil. The objectives of the present study were to identify the grasshopper defoliating heliconias in the municipality of Santo Antônio de Pádua, RJ (Brazil, to evaluate the effect of different levels of shade on the population of this grasshopper and the production parameters of heliconias, and to determine if this grasshopper has an oviposition preference among the heliconias evaluated. The experiment was in a completely randomized block design, in subdivided plots (four levels of shade in the plot, 0%, 30%, 50% and 80%, and four species of Heliconia: H. psittacorum, H. stricta, H. wagneriana and H. psittacorum x H. spathocircinata ‘Golden Torch’ in the subplot, with four replications. The grasshopper was identified as Cornops frenatum frenatum (Acrididae. An increase in shade resulted in a decrease in the number of oviposition holes from the grasshopper and the number of lateral buds. Shade did not influence the number of C. f. frenatum nymphs and adults and the number of flower stems. H. wagneriana was the most preferred species for oviposition by C. f. frenatum. Results suggested using screens to shade heliconia plants can help control C. f. frenatum populations, however, the light requirements of the heliconias should be considered to guarantee productivity.

  12. Prey change behaviour with predation threat, but demographic effects vary with prey density: experiments with grasshoppers and birds.

    Science.gov (United States)

    Belovsky, Gary E; Laws, Angela Nardoni; Slade, Jennifer B

    2011-04-01

    Increasingly, ecologists emphasize that prey frequently change behaviour in the presence of predators and these behavioural changes can reduce prey survival and reproduction as much or more than predation itself. However, the effects of behavioural changes on survival and reproduction may vary with prey density due to intraspecific competition. In field experiments, we varied grasshopper density and threat of avian predation and measured grasshopper behaviour, survival and reproduction. Grasshopper behaviour changed with the threat of predation and these behavioural changes were invariant with grasshopper density. Behavioural changes with the threat of predation decreased per capita reproduction over all grasshopper densities; whereas the behavioural changes increased survival at low grasshopper densities and then decreased survival at high densities. At low grasshopper densities, the total reproductive output of the grasshopper population remained unchanged with predation threat, but declined at higher densities. The effects of behavioural changes with predation threat varied with grasshopper density because of a trade-off between survival and reproduction as intraspecific competition increased with density. Therefore, resource availability may need to be considered when assessing how prey behavioural changes with predation threat affect population and food web dynamics. © 2011 Blackwell Publishing Ltd/CNRS.

  13. Grasshopper beam line for utilization of synchrotron radiation

    International Nuclear Information System (INIS)

    Saito, Norio; Suzuki, I.H.; Onuki, Hideo; Nishi, Morotake

    1989-01-01

    Optical characteristics of a new beam line consisting of a pre-mirror, a Grasshopper monochromator and a re-focusing mirror have been investigated. A ray-tracing calculation was performed for designing the mirrors so as to optimize the photon intensity and the spot size at the sample point. The intensity of the monochromatic soft x-ray was about 10 8 photons/(sec·100mA) at 25 A under the storage electron energy of 600 MeV with the minimum slit width which corresponded to a resolution of about 500. The sum of stray light and higher order components was less than 10% of the total intensity except around the C-K edge. Using an appropriate filter, it was reduced to less than a few percent. (author)

  14. γ-rays kill grasshopper primary spermatocytes in groups

    International Nuclear Information System (INIS)

    Al-Taweel, A.A.; Shawkit, M.A.; Fox, D.P.

    1985-01-01

    Primary spermatocyte killing by γ-rays was studied in the grasshopper Heteracris littoralis in which spermatogenic development occurs in cysts containing a maximum of 64 cells during the first meiotic division. Cell killing at this stage is not random and mainly involves the death of whole cysts. The dose-response curve for cell killing has complex kinetics with at least two components but lacks any shoulder at low doses, thus indicating no repair of the lethal damage. Cell loss is apparent from surviving cysts as early as 45 min post irradiation but loss of > 24 cells is incompatible with cyst survival. Loss of fewer than 24 cells also is not random since certain values for cell loss are frequently observed while other, interspersed values are not seen at all. (Auth.)

  15. Adverse effects of fullerenes (nC{sub 60}) spiked to sediments on Lumbriculus variegatus (Oligochaeta)

    Energy Technology Data Exchange (ETDEWEB)

    Pakarinen, K., E-mail: kukka.tervonen@uef.fi [Department of Biology, University of Eastern Finland, 80101 Joensuu (Finland); Petersen, E.J. [Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD (United States); Leppaenen, M.T.; Akkanen, J.; Kukkonen, J.V.K. [Department of Biology, University of Eastern Finland, 80101 Joensuu (Finland)

    2011-12-15

    Effects of fullerene-spiked sediment on a benthic organism, Lumbriculus variegatus (Oligochaeta), were investigated. Survival, growth, reproduction, and feeding rates were measured to assess possible adverse effects of fullerene agglomerates produced by water stirring and then spiked to a natural sediment. L. variegatus were exposed to 10 and 50 mg fullerenes/kg sediment dry mass for 28 d. These concentrations did not impact worm survival or reproduction compared to the control. Feeding activities were slightly decreased for both concentrations indicating fullerenes' disruptive effect on feeding. Depuration efficiency decreased in the high concentration only. Electron and light microscopy and extraction of the worm fecal pellets revealed fullerene agglomerates in the gut tract but not absorption into gut epithelial cells. Micrographs also indicated that 16% of the epidermal cuticle fibers of the worms were not present in the 50 mg/kg exposures, which may make worms susceptible to other contaminants. - Highlights: > Effects of fullerene-spiked sediment on black worms were investigated. > Survival, growth, reproduction, and feeding rates were measured. > Exposure did not impact worm survival or reproduction. > Feeding rates and depuration efficiency were decreased. > Worms transferred fullerenes from the sediment to the sediment surface. - Exposure to fullerene-spiked sediment decreased black worms' feeding and depuration efficiency, but fullerenes did not appear to be absorbed into the microvilli.

  16. Fecal estradiol and progesterone metabolite levels in the three-toed sloth (Bradypus variegatus

    Directory of Open Access Journals (Sweden)

    M. Mühlbauer

    2006-02-01

    Full Text Available The present study was carried out to assess the possibility of measuring fecal steroid hormone metabolites as a noninvasive technique for monitoring reproductive function in the three-toed sloth, Bradypus variegatus. Levels of the estradiol (E2 and progesterone (P4 metabolites were measured by radioimmunoassay in fecal samples collected over 12 weeks from 4 captive female B. variegatus sloths. The validation of the radioimmunoassay for evaluation of fecal steroid metabolites was carried out by collecting 10 blood samples on the same day as defecation. There was a significant direct correlation between the plasma and fecal E2 and P4 levels (P < 0.05, Pearson's test, thereby validating this noninvasive technique for the study of the estrous cycle in these animals. Ovulation was detected in two sloths (SL03 and SL04 whose E2 levels reached 2237.43 and 6713.26 pg/g wet feces weight, respectively, for over four weeks, followed by an increase in P4 metabolites reaching 33.54 and 3242.68 ng/g wet feces weight, respectively. Interestingly, SL04, which presented higher levels of E2 and P4 metabolites, later gave birth to a healthy baby sloth. The results obtained indicate that this is a reliable technique for recording gonadal steroid secretion and thereby reproduction in sloths.

  17. Can behavioural responses of Lumbriculus variegatus (Oligochaeta) assess sediment toxicity? A case study with sediments exposed to acid mine drainage

    International Nuclear Information System (INIS)

    Sardo, A.M.; Soares, A.M.V.M.

    2010-01-01

    The Sao Domingos mine (Portugal) is, potentially, a good site for ecotoxicological studies, due to a pH and metal gradient of acid mine drainage. In this study, the toxicity of several mine sediments was evaluated using the aquatic oligochaete Lumbriculus variegatus as a test organism. Our hypothesis was that exposure to contaminated sediments would cause behavioural early warning responses in L. variegatus. Five sites, with pH ranging from 2.5 to 6.5, and with associated metals, were investigated. The results showed poor sediment quality in most of the collected sediments and Fe, S and As were the dominant elements in the samples. High mortalities were observed, ranging from 32.6 to 100%, indicating severe contamination. The collected sediments did not support good L. variegatus growth and significantly changed its behaviour. Early warning responses consisted of decreased locomotion and decreased peristaltic movements. A behaviour inhibition will affect the ecosystem balance by limiting the organisms' ability to avoid capture, which leads to a higher risk of predation. - Behavioural responses of the aquatic oligochaeta Lumbriculus variegatus may be used to detect early warning responses.

  18. Effects of feeding and organism loading rate on PCB accumulation by Lumbriculus variegatus in sediment bioaccumulation testing

    Science.gov (United States)

    Sediment bioaccumulation test methods published by USEPA and ASTM in 2000 specify that the Lumbriculus variegatus, a freshwater oligochaete, should not be fed during the 28-day exposure and recommends an organism loading rate of total organic carbon in sediment to organism dry we...

  19. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus

    NARCIS (Netherlands)

    Laarhoven, Bob; Elissen, H.J.H.; Temmink, H.; Buisman, C.J.N.

    2016-01-01

    An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv). The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water

  20. Chronic exposure of the oligochaete Lumbriculus variegatus to Polycyclic Aromatic Compounds (PACs): Bioavailability and effects on reproduction

    NARCIS (Netherlands)

    León Paumen, M.; Stol, P.; ter Laak, T.L.; Kraak, M.H.S.; van Gestel, C.A.M.; Admiraal, W.

    2008-01-01

    This study aimed to monitor PAC availability to the oligochaete Lumbriculus variegatus during 28 days of exposure to spiked sediments, in order to obtain reliable chronic effect concentrations for reproduction. Sediment toxicity tests were performed using three pairs of PAC isomers: two homocyclic

  1. Chronic exposure of the oligochaete Lumbriculus variegatus to polycyclic aromatic compounds (PACs): bioavailability and effects on reproduction.

    NARCIS (Netherlands)

    Leon Paumen, M.; Stol, P.; ter Laak, T.L.; Kraak, M.H.S.; van Gestel, C.A.M.; Admiraal, W.

    2008-01-01

    This study aimed to monitor PAC availability to the oligochaete Lumbriculus variegatus during 28 days of exposure to spiked sediments, in order to obtain reliable chronic effect concentrations for reproduction. Sediment toxicity tests were performed using three pairs of PAC isomers: two homocyclic

  2. Molecular Ecological Basis of Grasshopper (Oedaleus asiaticus) Phenotypic Plasticity under Environmental Selection

    Science.gov (United States)

    Qin, Xinghu; Hao, Kun; Ma, Jingchuan; Huang, Xunbing; Tu, Xiongbing; Ali, Md. Panna; Pittendrigh, Barry R.; Cao, Guangchun; Wang, Guangjun; Nong, Xiangqun; Whitman, Douglas W.; Zhang, Zehua

    2017-01-01

    While ecological adaptation in insects can be reflected by plasticity of phenotype, determining the causes and molecular mechanisms for phenotypic plasticity (PP) remains a crucial and still difficult question in ecology, especially where control of insect pests is involved. Oedaleus asiaticus is one of the most dominant pests in the Inner Mongolia steppe and represents an excellent system to study phenotypic plasticity. To better understand ecological factors affecting grasshopper phenotypic plasticity and its molecular control, we conducted a full transcriptional screening of O. asiaticus grasshoppers reared in four different grassland patches in Inner Mongolia. Grasshoppers showed different degrees of PP associated with unique gene expressions and different habitat plant community compositions. Grasshopper performance variables were susceptible to habitat environment conditions and closely associated with plant architectures. Intriguingly, eco-transcriptome analysis revealed five potential candidate genes playing important roles in grasshopper performance, with gene expression closely relating to PP and plant community factors. By linking the grasshopper performances to gene profiles and ecological factors using canonical regression, we first demonstrated the eco-transcriptomic architecture (ETA) of grasshopper phenotypic traits (ETAGPTs). ETAGPTs revealed plant food type, plant density, coverage, and height were the main ecological factors influencing PP, while insect cuticle protein (ICP), negative elongation factor A (NELFA), and lactase-phlorizin hydrolase (LCT) were the key genes associated with PP. Our study gives a clear picture of gene-environment interaction in the formation and maintenance of PP and enriches our understanding of the transcriptional events underlying molecular control of rapid phenotypic plasticity associated with environmental variability. The findings of this study may also provide new targets for pest control and highlight the

  3. Molecular Ecological Basis of Grasshopper (Oedaleus asiaticus Phenotypic Plasticity under Environmental Selection

    Directory of Open Access Journals (Sweden)

    Xinghu Qin

    2017-10-01

    Full Text Available While ecological adaptation in insects can be reflected by plasticity of phenotype, determining the causes and molecular mechanisms for phenotypic plasticity (PP remains a crucial and still difficult question in ecology, especially where control of insect pests is involved. Oedaleus asiaticus is one of the most dominant pests in the Inner Mongolia steppe and represents an excellent system to study phenotypic plasticity. To better understand ecological factors affecting grasshopper phenotypic plasticity and its molecular control, we conducted a full transcriptional screening of O. asiaticus grasshoppers reared in four different grassland patches in Inner Mongolia. Grasshoppers showed different degrees of PP associated with unique gene expressions and different habitat plant community compositions. Grasshopper performance variables were susceptible to habitat environment conditions and closely associated with plant architectures. Intriguingly, eco-transcriptome analysis revealed five potential candidate genes playing important roles in grasshopper performance, with gene expression closely relating to PP and plant community factors. By linking the grasshopper performances to gene profiles and ecological factors using canonical regression, we first demonstrated the eco-transcriptomic architecture (ETA of grasshopper phenotypic traits (ETAGPTs. ETAGPTs revealed plant food type, plant density, coverage, and height were the main ecological factors influencing PP, while insect cuticle protein (ICP, negative elongation factor A (NELFA, and lactase-phlorizin hydrolase (LCT were the key genes associated with PP. Our study gives a clear picture of gene-environment interaction in the formation and maintenance of PP and enriches our understanding of the transcriptional events underlying molecular control of rapid phenotypic plasticity associated with environmental variability. The findings of this study may also provide new targets for pest control and

  4. Construction of a GeogDetector-based model system to indicate the potential occurrence of grasshoppers in Inner Mongolia steppe habitats.

    Science.gov (United States)

    Shen, J; Zhang, N; Gexigeduren; He, B; Liu, C-Y; Li, Y; Zhang, H-Y; Chen, X-Y; Lin, H

    2015-06-01

    Grasshopper plagues have seriously disturbed grassland ecosystems in Inner Mongolia, China. The accurate prediction of grasshopper infestations and control of grasshopper plagues have become urgent needs. We sampled 234, 342, 335, and 369 plots in Xianghuangqi County of Xilingol League in 2010, 2011, 2012, and 2013, respectively, and measured the density of the most dominant grasshopper species, Oedaleus decorus asiaticus, and the latitude, longitude, and associated relatively stable habitat factors at each plot. We used Excel-GeogDetector software to explore the effects of individual habitat factors and the two-factor interactions on grasshopper density. We estimated the membership of each grasshopper density rank and determined the weights of each habitat category. These results were used to construct a model system evaluating grasshopper habitat suitability. The results showed that our evaluation system was reliable and the fuzzy evaluation scores of grasshopper habitat suitability were good indicators of potential occurrence of grasshoppers. The effects of the two-factor interactions on grasshopper density were greater than the effects of any individual factors. O. d. asiaticus was most likely to be found at elevations of 1300-1400 m, flat terrain or slopes of 4-6°, typical chestnut soil with 70-80% sand content in the top 5 cm of soil, and medium-coverage grassland. The species preferred temperate bunchgrass steppe dominated by Stipa krylovii and Cleistogenes squarrosa. These findings may be used to improve models to predict grasshopper occurrence and to develop management guidelines to control grasshopper plagues by changing habitats.

  5. Rapid top-down regulation of plant C:N:P stoichiometry by grasshoppers in an Inner Mongolia grassland ecosystem.

    Science.gov (United States)

    Zhang, Guangming; Han, Xingguo; Elser, James J

    2011-05-01

    Understanding how food web interactions alter the processing of limiting nutrient elements is an important goal of ecosystem ecology. An experiment manipulating densities of the grasshopper Oedaleus asiaticus was performed to assess top-down effects of grasshoppers on C:N:P stoichiometry of plants and soil in a grassland ecosystem in Inner Mongolia (China). With increased grasshopper feeding, plant biomass declined fourfold, litter abundance increased 30%, and the plant community became dominated by non-host plant taxa. Plant stoichiometric response depended on whether or not the plant was a grasshopper host food species: C:N and C:P ratios increased with increasing grasshopper density (GD) for host plants but decreased in non-host plants. These data suggest either a direct transfer of grasshopper-recycled nutrients from host to non-host plants or a release of non-host plants from nutrient competition with heavily grazed host plants. Litterfall C:N and C:P decreased across moderate levels of grasshopper density but no effects on C:N:P stoichiometry in the surface soil were observed, possibly due to the short experimental period. Our observations of divergent C:N:P stoichiometric response among plant species highlight the important role of grasshopper herbivory in regulating plant community structure and nutrient cycling in grassland ecosystems.

  6. Infection of two non-target grasshoppers by the biological control agent Metarhizium anisopliae var. acridum in the Sahel

    DEFF Research Database (Denmark)

    Fisker, E. N.; Eilenberg, J.; Langewald, J.

    2006-01-01

    Fungal isolates from grasshoppers of the family Acrididae are suspected to be less virulent to grasshoppers of the family Pyrgomorphidae. The biological control agent Metarhizium anisopliae var. acridum was isolated from an acridid and is thus hypothesized to be less virulent to pyrgomorphids. Th...

  7. Phylogeography and genetic identification of the newly-discovered populations of torrent salamanders (Rhyacotriton cascade and R. variegatus) in the central Cascades (USA)

    Science.gov (United States)

    Wagner, R.S.; Miller, Mark P.; Haig, Susan M.

    2006-01-01

    Newly discovered populations of Rhyacotritonidae were investigated for taxonomic identity, hybridization, and sympatry. Species in the genus Rhyacotriton have been historically difficult to identify using morphological characters. Mitochondrial (mtDNA) 16S ribosomal RNA sequences (491 bp) and allozymes (6 loci) were used to identify the distribution of populations occurring intermediate between the previously described ranges of R. variegatus and R. cascadae in the central Cascade Mountain region of Oregon. Allozyme and mitochondrial sequence data both indicated the presence of two distinct evolutionary lineages, with each lineage corresponding to the allopatric distribution of R. cascadae and R. variegatus. Results suggest the Willamette River acts as a phylogeographic barrier limiting the distribution of both species, although we cannot exclude the possibility that reproductive isolation also exists that reinforces species' distributions. This study extends the previously described geographical ranges of both R. cascadae and R. variegatus and defines an eastern range limit for R. variegatus conservation efforts.

  8. "Ant" and "grasshopper" life-history strategies in Saccharomyces cerevisiae.

    Science.gov (United States)

    Spor, Aymé; Wang, Shaoxiao; Dillmann, Christine; de Vienne, Dominique; Sicard, Delphine

    2008-02-13

    From the evolutionary and ecological points of view, it is essential to distinguish between the genetic and environmental components of the variability of life-history traits and of their trade-offs. Among the factors affecting this variability, the resource uptake rate deserves particular attention, because it depends on both the environment and the genetic background of the individuals. In order to unravel the bases of the life-history strategies in yeast, we grew a collection of twelve strains of Saccharomyces cerevisiae from different industrial and geographical origins in three culture media differing for their glucose content. Using a population dynamics model to fit the change of population size over time, we estimated the intrinsic growth rate (r), the carrying capacity (K), the mean cell size and the glucose consumption rate per cell. The life-history traits, as well as the glucose consumption rate, displayed large genetic and plastic variability and genetic-by-environment interactions. Within each medium, growth rate and carrying capacity were not correlated, but a marked trade-off between these traits was observed over the media, with high K and low r in the glucose rich medium and low K and high r in the other media. The cell size was tightly negatively correlated to carrying capacity in all conditions. The resource consumption rate appeared to be a clear-cut determinant of both the carrying capacity and the cell size in all media, since it accounted for 37% to 84% of the variation of those traits. In a given medium, the strains that consume glucose at high rate have large cell size and low carrying capacity, while the strains that consume glucose at low rate have small cell size but high carrying capacity. These two contrasted behaviors may be metaphorically defined as "ant" and "grasshopper" strategies of resource utilization. Interestingly, a strain may be "ant" in one medium and "grasshopper" in another. These life-history strategies are discussed

  9. Sex chromosome diversity in Armenian toad grasshoppers (Orthoptera, Acridoidea, Pamphagidae)

    Science.gov (United States)

    Bugrov, Alexander G.; Jetybayev, Ilyas E.; Karagyan, Gayane H.; Rubtsov, Nicolay B.

    2016-01-01

    Abstract Although previous cytogenetic analysis of Pamphagidae grasshoppers pointed to considerable karyotype uniformity among most of the species in the family, our study of species from Armenia has discovered other, previously unknown karyotypes, differing from the standard for Pamphagidae mainly in having unusual sets of sex chromosomes. Asiotmethis turritus (Fischer von Waldheim, 1833), Paranocaracris rubripes (Fischer von Waldheim, 1846), and Nocaracris cyanipes (Fischer von Waldheim, 1846) were found to have the karyotype 2n♂=16+neo-XY and 2n♀=16+neo-XX, the neo-X chromosome being the result of centromeric fusion of an ancient acrocentric X chromosome and a large acrocentric autosome. The karyotype of Paranothrotes opacus (Brunner von Wattenwyl, 1882) was found to be 2n♂=14+X1X2Y and 2n♀=14+X1X1X2X2., the result of an additional chromosome rearrangement involving translocation of the neo-Y and another large autosome. Furthermore, evolution of the sex chromosomes in these species has involved different variants of heterochromatinization and miniaturization of the neo-Y. The karyotype of Eremopeza festiva (Saussure, 1884), in turn, appeared to have the standard sex determination system described earlier for Pamphagidae grasshoppers, 2n♂=18+X0 and 2n♀=18+XX, but all the chromosomes of this species were found to have small second C-positive arms. Using fluorescent in situ hybridization (FISH) with 18S rDNA and telomeric (TTAGG)n DNA repeats to yield new data on the structural organization of chromosomes in the species studied, we found that for most of them, clusters of repeats homologous to 18S rDNA localize on two, three or four pairs of autosomes and on the X. In Eremopeza festiva, however, FISH with labelled 18S rDNA painted C-positive regions of all autosomes and the X chromosome; clusters of telomeric repeats localized primarily on the ends of the chromosome arms. Overall, we conclude that the different stages of neo-Y degradation revealed in

  10. "Ant" and "grasshopper" life-history strategies in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Aymé Spor

    Full Text Available From the evolutionary and ecological points of view, it is essential to distinguish between the genetic and environmental components of the variability of life-history traits and of their trade-offs. Among the factors affecting this variability, the resource uptake rate deserves particular attention, because it depends on both the environment and the genetic background of the individuals. In order to unravel the bases of the life-history strategies in yeast, we grew a collection of twelve strains of Saccharomyces cerevisiae from different industrial and geographical origins in three culture media differing for their glucose content. Using a population dynamics model to fit the change of population size over time, we estimated the intrinsic growth rate (r, the carrying capacity (K, the mean cell size and the glucose consumption rate per cell. The life-history traits, as well as the glucose consumption rate, displayed large genetic and plastic variability and genetic-by-environment interactions. Within each medium, growth rate and carrying capacity were not correlated, but a marked trade-off between these traits was observed over the media, with high K and low r in the glucose rich medium and low K and high r in the other media. The cell size was tightly negatively correlated to carrying capacity in all conditions. The resource consumption rate appeared to be a clear-cut determinant of both the carrying capacity and the cell size in all media, since it accounted for 37% to 84% of the variation of those traits. In a given medium, the strains that consume glucose at high rate have large cell size and low carrying capacity, while the strains that consume glucose at low rate have small cell size but high carrying capacity. These two contrasted behaviors may be metaphorically defined as "ant" and "grasshopper" strategies of resource utilization. Interestingly, a strain may be "ant" in one medium and "grasshopper" in another. These life

  11. EXTENDING THE VIABILITY OF SPERMATOZOA AND EGGS OF THE SEA URCHIN LYTECHINUS VARIEGATUS.

    Science.gov (United States)

    Malgarin, Jéssica; Resgalla, Charrid

    2015-01-01

    The storage of spermatozoa and eggs of the sea urchin Lytecninus variegatus can meet the demand of different human activities. To develop a protocol easy to reproduce for spermatozoa cryopreservation and cooling of the eggs of the sea urchin. Different formulations of artificial sea water were tested for their effectiveness in the freezing of sea urchin spermatozoa and storage of the eggs. Protocol for freezing of spermatozoa in liquid nitrogen presented the positive results when the cryoprotectant solution was diluted in artificial seawater free of calcium and magnesium. For the conservation of the eggs by cooling, the calcium-free artificial sea water, the calcium- and magnesium-free sea water, and the low-sodium water proved more efficient in preserving the integrity of the eggs. The results showed success in the freezing protocol of spermatozoa and cooling of the eggs mainly in artificial calcium- and magnesium-free sea water.

  12. A kinematic study of pulsation in the dorsal blood vessel of the blackworm, Lumbriculus variegatus

    Directory of Open Access Journals (Sweden)

    Kameko Halfmann

    2011-01-01

    Full Text Available The aquatic oligochaete Lumbriculus variegatus has a segmented, dorsal blood vessel (DBV that acts as a peristaltic pump to move blood through the animal's closed circulatory system. We conducted a kinematic study using videography and computational modeling as a first step toward understanding the control of DBV pulsation. Results suggested that pulse rates were highest in the posterior segments, while interpulse intervals and intersegmental delays were longest in the midbody segments. Differences in the interpulse interval distributions across regions suggest that some peristaltic waves initiated in the posterior segments do not propagate all the way to the anterior segments. A simple model consisting of a chain of excitable neuromuscular units replicated these kinetics. This model may be useful in future research aimed at understanding the modulatory effect of biogenic amines on peristalsis of the DBV. Moreover, research into the mechanisms of peristalsis of the DBV may lead to insights into disorders of peristalsis in human and veterinary medicine

  13. Isolation Of Compounds Of Steroids Teripang Gamat (Stichopus variegatus With Various Types Of Solvents

    Directory of Open Access Journals (Sweden)

    Meydia Meydia

    2016-12-01

    Full Text Available Sea cucumber is one of the fisheries commodity that has an important economic value. Generally istraded in dried form (beche-de-mer. One of thebioactive substances contained in sea cucumber is steroidcompounds that serves as an aphrodisiac and sex reversal. The purpose of this study was to extract thesteroid of the gamma sea cucumber by using three types of solvents (methanol, ethyl acetate and hexaneand get the best solvent in producing the highest yield of the steroids. The study revealed that steroid ofgamma sea cucumber (Stichopus variegatus dissolved completely ethyl acetate (semi-polar solvent duringthe first phase, second phase and the third phase of extraction. In the methanol (polar solvent steroids onlydissolved in the first extraction phase, while using the hexane (non polar solvent steroid was undetectable.Fractionation by thin layer chromatography was obtained two fractions that identified as cholesterol (Rf =0.96 and testosterone (Rf = 0.91.

  14. Aktivitas Inhibitor Enzim Pengubah Angiotensin (ACE dan Antioksidan Peptida Kolagen dari Teripang Gama (Stichopus variegatus

    Directory of Open Access Journals (Sweden)

    M. Habbib Khirzin

    2015-05-01

    Full Text Available Teripang merupakan salah satu echinodermata yang memiliki kandungan protein tinggi dan sekitar 70% dari proteinnya merupakan kolagen. Tujuan penelitian ini adalah untuk mengetahui aktivitas inhibitor Angiotensin Converting Enzyme (ACE dan antioksidan dari peptida kolagen teripang Gama (Stichopus variegatus. Ekstraksi kolagen dilakukan menggunakan asam asetat 0,5 M. Peptida kolagen diperoleh melalui hidrolisis kolagen menggunakan enzim pepsin dengan konsentrasi 0,1 U/g kolagen, selama 0; 30; 60; 90; 120; 180; dan 240 menit. Aktivitas inhibitor ACE dan antioksidan peptida kolagen diuji dengan metode spektroskopi. Kolagen yang dihasilkan memiliki rendemen 16,40% dengan berat molekul 130,33 kDa. Aktivitas inhibitor ACE tertinggi dihasilkan dari proses hidrolisis selama 180 menit dengan penghambatan sebesar 82,31%, sedangkan aktivitas antioksidan tertinggi dihasilkan oleh peptida kolagen dari hidrolisis kolagen selama 120 menit dengan nilai IC50 1,9 mg/ml.

  15. Effects of Moringa oleifera leaf extract on morphological and ...

    African Journals Online (AJOL)

    Zonocerus variegatus infestation has been found to cause a lot of devastation in the production of cassava crop plants in tropical and subtropical areas. Understanding the efficacy of Moringa oleifera leaf extract on controlling Z. variegatus is desired. The present study was conducted in the Department of Crop Science ...

  16. Monitoring grasshopper and locust habitats in Sahelian Africa using GIS and remote sensing technology

    Science.gov (United States)

    Tappan, G. Gray; Moore, Donald G.; Knauseberger, Walter I.

    1991-01-01

    Development programmes in Sahelian Africa are beginning to use geographic information system (GIS) technology. One of the GIS and remote sensing programmes introduced to the region in the late 1980s was the use of seasonal vegetation maps made from satellite data to support grasshopper and locust control. Following serious outbreaks of these pests in 1987, the programme addressed a critical need, by national and international crop protection organizations, to monitor site-specific dynamic vegetation conditions associated with grasshopper and locust breeding. The primary products used in assessing vegetation conditions were vegetation index (greenness) image maps derived from National Oceanic and Atmospheric Administration satellite imagery. Vegetation index data were integrated in a GIS with digital cartographic data of individual Sahelian countries. These near-real-time image maps were used regularly in 10 countries for locating potential grasshopper and locust habitats. The programme to monitor vegetation conditions is currently being institutionalized in the Sahel.

  17. Morphometric Variations in the Grasshopper, Chromacris speciosa from Two Localities of Pernambuco in Northeastern Brazil

    Science.gov (United States)

    Cisneiros, Roberta Araújo; de Almeida, Argus Vasconcelos; de Melo, Gabriel Rivas; da Câmara, Cláudio Augusto Gomes

    2012-01-01

    The present study describes morphometric variations in the grasshopper, Chromacris speciosa (Thunberg, 1824) (Orthoptera: Acridoidea: Romaleidae) from two locations in the state of Pernambuco, Brazil. The distance between the sites chosen for collections (Recife and São Lourenço da Mata) is approximately 16 km. The investigation was based on a comparative study of external morphological characteristics of the grasshoppers. Morphometric measurements took into account the different body parts and appendages. Statistical analysis of the measurements revealed significant differences in the size of the specimens between the two locations. Homogeneity tests of the covariance and equality matrices between mean vectors of the results revealed that the grasshopper populations in Recife and São Lourenço da Mata are distinctly different. These findings provide morphological evidence for intraspecific variation in morphological characteristics of the C. speciosa populations from the two locations. PMID:23421530

  18. Metabolism by grasshoppers of volatile chemical constituents from Mangifera indica and Solanum paniculatum leaves.

    Science.gov (United States)

    Ramos, Clécio S; Ramos, Natália S M; Da Silva, Rodolfo R; Da Câmara, Cláudio A G; Almeida, Argus V

    2012-12-01

    The chemical volatiles from plant leaves and their biological activities have been extensively studied. However, no studies have addressed plant-chemical volatiles after undergoing the digestive process in host insects. Here we describe for the first time chemical profiles of volatile constituents from Solanum paniculatum and Mangifera indica leaves metabolized by grasshoppers. Both profiles were qualitatively and quantitatively different from the profiles of non-metabolized leaves. The amount of nerolidol, the major constituent of S. paniculatum leaves, decreased and other sesquiterpenes, such as spathulenol, were formed during the digestive process of the grasshopper Chromacris speciosa. In M. indica, the presence of phenylpropanoids was observed (dillapiole, Z-asarone, E-asarone and γ-asarone) in the leaves metabolized by the grasshopper Tropidacris collaris, but these compounds were not found in the non-metabolized leaves. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Human population, grasshopper and plant species richness in European countries

    Science.gov (United States)

    Steck, Claude E.; Pautasso, Marco

    2008-11-01

    Surprisingly, several studies over large scales have reported a positive spatial correlation of people and biodiversity. This pattern has important implications for conservation and has been documented for well studied taxa such as plants, amphibians, reptiles, birds and mammals. However, it is unknown whether the pattern applies also to invertebrates other than butterflies and more work is needed to establish whether the species-people relationship is explained by both variables correlating with other environmental factors. We studied whether grasshopper species richness (Orthoptera, suborder Caelifera) is related to human population size in European countries. As expected, the number of Caelifera species increases significantly with increasing human population size. But this is not the case when controlling for country area, latitude and number of plant species. Variations in Caelifera species richness are primarily associated with variations in plant species richness. Caelifera species richness also increases with decreasing mean annual precipitation, Gross Domestic Product per capita (used as an indicator for economic development) and net fertility rate of the human population. Our analysis confirms the hypothesis that the broad-scale human population-biodiversity correlations can be explained by concurrent variations in factors other than human population size such as plant species richness, environmental productivity, or habitat heterogeneity. Nonetheless, more populated countries in Europe still have more Caelifera species than less populated countries and this poses a particular challenge for conservation.

  20. Synchrotron imaging of the grasshopper tracheal system: morphological and physiological components of tracheal hypermetry

    International Nuclear Information System (INIS)

    Greenlee, K.J.; Henry, J.R.; Kirkton, S.D.; Westneat, M.W.; Fezzaa, K.; Lee, W.; Harrison, J.F.

    2009-01-01

    As grasshoppers increase in size during ontogeny, they have mass specifically greater whole body tracheal and tidal volumes and ventilation than predicted by an isometric relationship with body mass and body volume. However, the morphological and physiological bases to this respiratory hypermetry are unknown. In this study, we use synchrotron imaging to demonstrate that tracheal hypermetry in developing grasshoppers (Schistocerca americana) is due to increases in air sacs and tracheae and occurs in all three body segments, providing evidence against the hypothesis that hypermetry is due to gaining flight ability. We also assessed the scaling of air sac structure and function by assessing volume changes of focal abdominal air sacs. Ventilatory frequencies increased in larger animals during hypoxia (5% O 2 ) but did not scale in normoxia. For grasshoppers in normoxia, inflated and deflated air sac volumes and ventilation scaled hypermetrically. During hypoxia (5% O 2 ), many grasshoppers compressed air sacs nearly completely regardless of body size, and air sac volumes scaled isometrically. Together, these results demonstrate that whole body tracheal hypermetry and enhanced ventilation in larger/older grasshoppers are primarily due to proportionally larger air sacs and higher ventilation frequencies in larger animals during hypoxia. Prior studies showed reduced whole body tracheal volumes and tidal volume in late-stage grasshoppers, suggesting that tissue growth compresses air sacs. In contrast, we found that inflated volumes, percent volume changes, and ventilation were identical in abdominal air sacs of late-stage fifth instar and early-stage animals, suggesting that decreasing volume of the tracheal system later in the instar occurs in other body regions that have harder exoskeleton.

  1. Grasshopper community response to climatic change: variation along an elevational gradient.

    Science.gov (United States)

    Nufio, César R; McGuire, Chris R; Bowers, M Deane; Guralnick, Robert P

    2010-09-23

    The impacts of climate change on phenological responses of species and communities are well-documented; however, many such studies are correlational and so less effective at assessing the causal links between changes in climate and changes in phenology. Using grasshopper communities found along an elevational gradient, we present an ideal system along the Front Range of Colorado USA that provides a mechanistic link between climate and phenology. This study utilizes past (1959-1960) and present (2006-2008) surveys of grasshopper communities and daily temperature records to quantify the relationship between amount and timing of warming across years and elevations, and grasshopper timing to adulthood. Grasshopper communities were surveyed at four sites, Chautauqua Mesa (1752 m), A1 (2195 m), B1 (2591 m), and C1 (3048 m), located in prairie, lower montane, upper montane, and subalpine life zones, respectively. Changes to earlier first appearance of adults depended on the degree to which a site warmed. The lowest site showed little warming and little phenological advancement. The next highest site (A1) warmed a small, but significant, amount and grasshopper species there showed inconsistent phenological advancements. The two highest sites warmed the most, and at these sites grasshoppers showed significant phenological advancements. At these sites, late-developing species showed the greatest advancements, a pattern that correlated with an increase in rate of late-season warming. The number of growing degree days (GDDs) associated with the time to adulthood for a species was unchanged across the past and present surveys, suggesting that phenological advancement depended on when a set number of GDDs is reached during a season. Our analyses provide clear evidence that variation in amount and timing of warming over the growing season explains the vast majority of phenological variation in this system. Our results move past simple correlation and provide a stronger process

  2. Grasshopper community response to climatic change: variation along an elevational gradient.

    Directory of Open Access Journals (Sweden)

    César R Nufio

    2010-09-01

    Full Text Available The impacts of climate change on phenological responses of species and communities are well-documented; however, many such studies are correlational and so less effective at assessing the causal links between changes in climate and changes in phenology. Using grasshopper communities found along an elevational gradient, we present an ideal system along the Front Range of Colorado USA that provides a mechanistic link between climate and phenology.This study utilizes past (1959-1960 and present (2006-2008 surveys of grasshopper communities and daily temperature records to quantify the relationship between amount and timing of warming across years and elevations, and grasshopper timing to adulthood. Grasshopper communities were surveyed at four sites, Chautauqua Mesa (1752 m, A1 (2195 m, B1 (2591 m, and C1 (3048 m, located in prairie, lower montane, upper montane, and subalpine life zones, respectively. Changes to earlier first appearance of adults depended on the degree to which a site warmed. The lowest site showed little warming and little phenological advancement. The next highest site (A1 warmed a small, but significant, amount and grasshopper species there showed inconsistent phenological advancements. The two highest sites warmed the most, and at these sites grasshoppers showed significant phenological advancements. At these sites, late-developing species showed the greatest advancements, a pattern that correlated with an increase in rate of late-season warming. The number of growing degree days (GDDs associated with the time to adulthood for a species was unchanged across the past and present surveys, suggesting that phenological advancement depended on when a set number of GDDs is reached during a season.Our analyses provide clear evidence that variation in amount and timing of warming over the growing season explains the vast majority of phenological variation in this system. Our results move past simple correlation and provide a stronger

  3. Influence of weather variables and plant communities on grasshopper density in the Southern Pampas, Argentina.

    Science.gov (United States)

    de Wysiecki, María Laura; Arturi, Marcelo; Torrusio, Sandra; Cigliano, María Marta

    2011-01-01

    A study was conducted to evaluate the influence of weather (precipitation and temperature) and plant communities on grasshopper density over a 14-year period (1996-2009) in Benito Juárez County, Southern Pampas, Argentina. Total density strongly varied among plant communities. Highest values were registered in 2001 and 2003 in highly disturbed pastures and in 2002 and 2009 in halophilous grasslands. Native grasslands had the lowest density values. Seasonal precipitation and temperature had no significant effect on total grasshopper density. Dichroplus elongatus (Giglio-Tos) (Orthoptera: Acridoidea), Covasacris pallidinota (Bruner), Dichroplus pratensis Bruner, Scotussa lemniscata Stål, Borellia bruneri (Rehn) and Dichroplus maculipennis (Blanchard) comprised, on average, 64% of the grasshopper assemblages during low density years and 79% during high density years. Dichroplus elongatus, S. lemniscata and C. pallidinota were the most abundant species in 2001, 2002 and 2003, while D. elongatus, B. brunneri and C. pallidinota in 2009. Dichroplus elongatus and D. pratensis, mixed feeders species, were positively affected by summer rainfall. This suggests that the increase in summer precipitation had a positive effect on the quantity and quality forage production, affecting these grasshopper populations. Scotussa lemniscata and C. pallidinota were negatively affected by winter and fall temperature, possibly affecting the embryonic development before diapause and hatching. Dichroplus elongatus and D. pratensis were associated with highly disturbed pastures, S. lemniscata with pastures and B. bruneri and D. maculipennis with halophilous grasslands. Covasacris pallidinota was closely associated with halophilous grasslands and moderately disturbed pastures. Weather conditions changed over the years, with 2001, 2002 and 2003 having excessive rainfall while 2008 and 2009 were the driest years since the study started. We suggest that although seasonal precipitation and

  4. [Diversity and distribution of grasshoppers (Orthoptera: Acridoidea) in grasslands of the Southern Pampas region, Argentina].

    Science.gov (United States)

    Mariottini, Yanina; De Wysiecki, María Laura; Lange, Carlos Ernesto

    2013-03-01

    In Argentina, the grasslands of Pampas region comprise approximately 15% of the country. As in other grasslands of the world, grasshoppers are among the most important native herbivores. Their economic importance has been recognized in Argentina since the mid to late nineteenth century, since outbreaks of different species have become recurrent phenomena. Therefore, the main objective of this work was to study their diversity and distribution in grasslands of the Southern Pampas region (Laprida county, Buenos Aires province), as one of the most affected areas. The study was conducted during five seasons (2005-10). Sampling sites were represented by the most common plant communities in this area, classified in four categories: native grasslands, disturbed grasslands, implanted pastures and halophilous grasslands. The samplings were conducted from mid-spring to early autumn, with five or six samples per season. We estimated the following population descriptors: species richness (S), eveness (E), dominance (J), and diversity index (H'). In order to evaluate the similitude of the grasshopper communities present in the different plant communities, we used qualitative and quantitative coefficients of similitude. A total of 22 species of grasshoppers were collected, of which 21 belong to the family Acrididae. The subfamily Melanoplinae was the most diverse with eight species. The largest species richness was recorded in native grasslands (18). The different communities of grasshoppers had similar indices of evenness and dominance (p>0.05). Considering all plant communities, the average value of Shannon-Wiener index was 1.58+/-0.075. There was a positive correlation between evenness index and species richness (pgrasshoppers species richness, and diversity of grasshoppers. According to the qualitative indices applied, the similitude between different grasshopper communities was higher than 60%. In general, the species that had a higher frequency of occurrence showed greater

  5. A test of the thermal melanism hypothesis in the wingless grasshopper Phaulacridium vittatum.

    Science.gov (United States)

    Harris, Rebecca M; McQuillan, Peter; Hughes, Lesley

    2013-01-01

    Altitudinal clines in melanism are generally assumed to reflect the fitness benefits resulting from thermal differences between colour morphs, yet differences in thermal quality are not always discernible. The intra-specific application of the thermal melanism hypothesis was tested in the wingless grasshopper Phaulacridium vittatum (Sjöstedt) (Orthoptera: Acrididae) first by measuring the thermal properties of the different colour morphs in the laboratory, and second by testing for differences in average reflectance and spectral characteristics of populations along 14 altitudinal gradients. Correlations between reflectance, body size, and climatic variables were also tested to investigate the underlying causes of clines in melanism. Melanism in P. vittatum represents a gradation in colour rather than distinct colour morphs, with reflectance ranging from 2.49 to 5.65%. In unstriped grasshoppers, darker morphs warmed more rapidly than lighter morphs and reached a higher maximum temperature (lower temperature excess). In contrast, significant differences in thermal quality were not found between the colour morphs of striped grasshoppers. In support of the thermal melanism hypothesis, grasshoppers were, on average, darker at higher altitudes, there were differences in the spectral properties of brightness and chroma between high and low altitudes, and temperature variables were significant influences on the average reflectance of female grasshoppers. However, altitudinal gradients do not represent predictable variation in temperature, and the relationship between melanism and altitude was not consistent across all gradients. Grasshoppers generally became darker at altitudes above 800 m a.s.l., but on several gradients reflectance declined with altitude and then increased at the highest altitude.

  6. Synchrotron imaging of the grasshopper tracheal system : morphological and physiological components of tracheal hypermetry.

    Energy Technology Data Exchange (ETDEWEB)

    Greenlee, K. J.; Henry, J. R.; Kirkton, S. D.; Westneat, M. W.; Fezzaa, K.; Lee, W.; Harrison, J. F.; North Dakota State Univ.; Arizona State Univ.; Union Coll.; Field Museum of Natural History

    2009-11-01

    As grasshoppers increase in size during ontogeny, they have mass specifically greater whole body tracheal and tidal volumes and ventilation than predicted by an isometric relationship with body mass and body volume. However, the morphological and physiological bases to this respiratory hypermetry are unknown. In this study, we use synchrotron imaging to demonstrate that tracheal hypermetry in developing grasshoppers (Schistocerca americana) is due to increases in air sacs and tracheae and occurs in all three body segments, providing evidence against the hypothesis that hypermetry is due to gaining flight ability. We also assessed the scaling of air sac structure and function by assessing volume changes of focal abdominal air sacs. Ventilatory frequencies increased in larger animals during hypoxia (5% O{sub 2}) but did not scale in normoxia. For grasshoppers in normoxia, inflated and deflated air sac volumes and ventilation scaled hypermetrically. During hypoxia (5% O{sub 2}), many grasshoppers compressed air sacs nearly completely regardless of body size, and air sac volumes scaled isometrically. Together, these results demonstrate that whole body tracheal hypermetry and enhanced ventilation in larger/older grasshoppers are primarily due to proportionally larger air sacs and higher ventilation frequencies in larger animals during hypoxia. Prior studies showed reduced whole body tracheal volumes and tidal volume in late-stage grasshoppers, suggesting that tissue growth compresses air sacs. In contrast, we found that inflated volumes, percent volume changes, and ventilation were identical in abdominal air sacs of late-stage fifth instar and early-stage animals, suggesting that decreasing volume of the tracheal system later in the instar occurs in other body regions that have harder exoskeleton.

  7. Revision of the grasshopper genus Sedulia Stål, 1878 (Acrididae: Catantopinae) from Malay Peninsula.

    Science.gov (United States)

    Tan, Ming Kai; Robillard, Tony; Kamaruddin, Khairul Nizam

    2016-05-02

    Southeast Asia is a highly biodiverse region with many species of grasshoppers described since the 19th century. Historical species descriptions are however often not comprehensive and do not meet the modern criteria of taxonomy. Previously used characters for identification need to be re-examined. Here, we aim to revise the taxonomy of the grasshopper genus Sedulia Stål, 1878. Using morphology and simple morphometry, we compared and investigated interspecific and intraspecific variations among the two species of Sedulia. We also redescribed both species and constructed a key to species and closely related genera.

  8. Stable Isotope Systematics in Grasshopper Assemblages Along an Elevation Gradient, Colorado

    Science.gov (United States)

    Kohn, M. J.; Evans, S.; Dean, J.; Nufio, C.

    2012-12-01

    Insects comprise over three quarters of all animal species, yet studies of body water isotopic composition are limited to only the cockroach, the hoverfly, and chironomid flies. These studies suggest that oxygen and hydrogen isotopic compositions in body water are primarily controlled by dietary water sources, with modification from respiratory and metabolic processes. In particular, outward diffusion of isotopically depleted water vapor through insect spiracles at low humidity enriches residual body water in 18O and 2H (D). Stable isotope compositions (δ18O and δD) also respond to gradients in elevation and humidity, but these influences remain poorly understood. In this study, we measured grasshopper body water and local vegetation isotopic compositions along an elevation gradient in Colorado to evaluate three hypotheses: 1) Insect body water isotopic composition is directly related to food source water composition 2) Water vapor transport alters body water isotopic compositions relative to original diet sources, and 3) Elevation gradients influence isotopic compositions in insect body water. Thirty-five species of grasshopper were collected from 14 locations in Colorado grasslands, ranging in elevation from 450 to 800 meters (n=131). Body water was distilled from previously frozen grasshopper specimens using a vacuum extraction line, furnaces (90 °C), and liquid nitrogen traps. Water samples were then analyzed for δ18O and δD on an LGR Liquid Water Isotope Analyzer, housed in the Department of Geosciences, Boise State University. Grasshopper body water isotopic compositions show wide variation, with values ranging between -76.64‰ to +42.82‰ in δD and -3.06‰ to +26.78‰ in δ18O. Precipitation δ18O values over the entire Earth excluding the poles vary by approximately 30‰, comparable to the total range measured in our single study area. Most grasshopper values deviate from the global meteoric water line relating δ18O and δD in precipitation

  9. Floral biology of Tropaeolum majus L. (Tropaeolaceae and its relation with Astylus variegatus activity (Germar 1824 (Coleoptera: Melyridae

    Directory of Open Access Journals (Sweden)

    Maria Emilia P.F. Silva

    2011-12-01

    Full Text Available Tropaeolum majus L. (nasturtium is a culture popularly known by its medicinal, ornamental and culinary utility. This work aimed to evaluate the interaction between Astylus variegatus (Germar 1824 (Coleoptera: Melyridae and the nasturtium flowers associated to the weeks of flourishing, in order to conceive the floral mechanims used by the species to attract A. variegatus. The insects collection was achieved with an entomologic net by the sweeping method, during the weekly flowering, at two hours, from 7am to 5pm. The studies of floral biology were carried out in twenty flowers by the analysis of measures and the arrangement of the floral parts. The nasturtium flower offers pollen and nectar to the insect as a compensation. However, it was observed that A. variegatus only collects pollen as a nutritious resource. Tropaeolum majus presents several flowers for each individual and, during the visits, A. variegatus walked throughout the interior of the flower, among the stamens and contacting the ventral region of its body, and while passing through the stigma it lodged the pollen. Sometimes, it uses the internal cavity for sheltering and mating. The visits occurred preferably on the second and fifth weeks of flourishing, with a populational fluctuation between 9am and 11am.Tropaeolum majus L. (capuchinha é uma cultura muito conhecida pelo seu valor medicinal, ornamental e culinário. O objetivo do trabalho foi avaliar a interação entre Astylus variegatus (Germar 1824 (Melyridae com as flores de capuchinha, associado às semanas de florescimento, visando entender os mecanismos florais utilizados pela espécie na atração de A. variegatus. A coleta dos insetos foi realizada com rede entomológica pelo método varredura durante a floração, semanalmente, a cada duas horas, no período de 7 às 17 horas. Os estudos da biologia floral foram realizados em vinte flores, analisando as medidas e disposição das peças florais. A flor de capuchinha

  10. Postzygotic incompatibilities between the pupfishes, Cyprinodon elegans and Cyprinodon variegatus: hybrid male sterility and sex ratio bias.

    Science.gov (United States)

    Tech, C

    2006-11-01

    I examined the intrinsic postzygotic incompatibilities between two pupfishes, Cyprinodon elegans and Cyprinodon variegatus. Laboratory hybridization experiments revealed evidence of strong postzygotic isolation. Male hybrids have very low fertility, and the survival of backcrosses into C. elegans was substantially reduced. In addition, several crosses produced female-biased sex ratios. Crosses involving C. elegans females and C. variegatus males produced only females, and in backcrosses involving hybrid females and C. elegans males, males made up approximately 25% of the offspring. All other crosses produced approximately 50% males. These sex ratios could be explained by genetic incompatibilities that occur, at least in part, on sex chromosomes. Thus, these results provide strong albeit indirect evidence that pupfish have XY chromosomal sex determination. The results of this study provide insight on the evolution of reproductive isolating mechanisms, particularly the role of Haldane's rule and the 'faster-male' theory in taxa lacking well-differentiated sex chromosomes.

  11. An experimental analysis of grasshopper community responses to fire and livestock grazing in a northern mixed-grass prairie.

    Science.gov (United States)

    Branson, David H; Sword, Gregory A

    2010-10-01

    The outcomes of grasshopper responses to both vertebrate grazing and fire vary across grassland ecosystems, and are strongly influenced by local climactic factors. Thus, the possible application of grazing and fire as components of an ecologically based grasshopper management strategy must be investigated in regional studies. In this study, we examined the effects of grazing and fire on grasshopper population density and community composition in a northern Great Plains mixed-grass prairie. We employed a large-scale, replicated, and fully-factorial manipulative experimental design across 4 yr to examine the separate and interactive effects of three grazing systems in burned and unburned habitats. Grasshopper densities were low throughout the 4-yr study and 1 yr of pretreatment sampling. There was a significant fire by grazing interaction effect on cumulative density and community composition, resulting from burned season long grazing pastures having higher densities than unburned pastures. Shannon diversity and grasshopper species richness were significantly higher with twice-over rotational livestock grazing. The ability to draw strong conclusions regarding the nature of species composition shifts and population changes in the presence of fire and grazing is complicated by the large site differences and low grasshopper densities. The results reinforce the importance of long-term research to examine the effects of habitat manipulation on grasshopper population dynamics.

  12. Influence of a large late summer precipitation event on food limitation and grasshopper population dynamics in a northern Great Plains grassland.

    Science.gov (United States)

    Branson, David H

    2008-06-01

    The complex interplay between grasshoppers, weather conditions, and plants that cause fluctuations in grasshopper populations remains poorly understood, and little is known about the ecological processes that generate grasshopper outbreaks. Grasshopper populations respond to interacting extrinsic and intrinsic factors, with yearly and decadal weather patterns and the timing of precipitation all potentially important. The effects of initial and increasing grasshopper densities on grasshopper survival and reproductive correlates were examined at a northern mixed-grass prairie site through manipulations of grasshopper densities inside 10-m2 cages. High-quality grass growth occurred after a 9.1-cm mid-August rain. Reduced proportional survival was apparent in the two higher density treatments before the rain, indicative of food-limited density-dependent mortality. However, the large late summer rainfall event mediated the effects of exploitative competition on demographic characteristics because of the high-quality vegetation growth. This led to weaker effects of food limitation on survival and reproduction at the end of the experiment. The results indicate a direct link between weather variation, resource quality and grasshopper population dynamics led to a severe grasshopper outbreak and show that infrequent large precipitation events can have significant effects on population dynamics. Additional research is needed to examine the importance of infrequent large precipitation events on grasshopper population dynamics in grassland ecosystems.

  13. A new genus of Tetratermini (Hymenoptera: Braconidae: Lysiterminae) parasitic on grasshoppers (Gryllacrididae)

    NARCIS (Netherlands)

    Achterberg, van C.; Steiner, H.

    1996-01-01

    The new genus Katytermus from Malaysia (type species: Katytermus palmicola spec. nov.) is described and illustrated. The new genus belongs to a new tribe, Tetratermini, of the subfamily Lysiterminae. The type species has been reared as a gregarious endoparasite of a "katydid" longhorn grasshopper

  14. A technique for studying digestion by grasshoppers using a 103Ruthenium-labelled marker

    International Nuclear Information System (INIS)

    Gandar, M.V.

    1981-01-01

    103 Ru-labelled tris (I,10-phenanthroline) ruthenium (II) chloride has proved to be a convenient marker in investigating digestion in grasshoppers. Assimilation efficiencies and the retension time of the food in the gut were measured. It is surmised that the technique described in this paper will be applicable to studies of a variety of chewing herbivorous insects. (author)

  15. Mesoherbivores affect grasshopper communities in a megaherbivore-dominated South African savannah

    NARCIS (Netherlands)

    van der Plas, Fons; Olff, Han

    African savannahs are among the few places on earth where diverse communities of mega- and meso-sized ungulate grazers dominate ecosystem functioning. Less conspicuous, but even more diverse, are the communities of herbivorous insects such as grasshoppers, which share the same food. Various studies

  16. The Fifth Enemy of the Ottoman Empire During World War I: Grasshoppers

    Directory of Open Access Journals (Sweden)

    Mehmet Ali YILDIRIM

    2014-12-01

    Full Text Available In Ottoman States there had always been grasshopper infestation now and then; and this caused some socio-economic problems and famine as a result. However, in the last years of the state, especially during World War I, the grasshoppers vastly influenced West and South Anatolia along with Aleppo and Syria regions; and the residents in these locations were negatively influenced. Acting to prevent a more destructive disaster, the Ministry of Agriculture and Commerce ensured that the law and regulations related to grasshopper problem - enacted in 1912 - were strictly implemented with the aim of a centralized control. Later, in 1916, an organization under the leadership of German experts arose. This way, despite the problems of war conditions, a more efficient, informed and institutional struggle started. Despite insufficient technological infrastructure and transportation and the lack of financial resources, a considerable amount of time and money were spent on the combat efforts against grasshoppers. During the war, the authorities pushed on fighting with limited sources available at hand. They strived for effective implementation of modern mass destroying methods together with traditional methods; raising awareness of the people for a full scale campaign; and ensuring their participation to the fight with every means at hand. The local civilian and military staffs were exploited to the maximum extent for the purpose. Finally, the efforts were not wasted and this campaign became successful. As a result of the efforts, important results were accomplished

  17. Embryonic development rates of northern grasshoppers (Orthoptera: Acrididae): implications for climate change and habitat management

    Science.gov (United States)

    Temperature-dependent rates of embryonic development are a primary determinant of the life cycle of many species of grasshoppers which, in cold climates, spend two winters in the egg stage. Knowledge of embryonic developmental rates is important for an assessment of the effects of climate change and...

  18. Grasshoppers regulate N:p stoichiometric homeostasis by changing phosphorus contents in their frass.

    Science.gov (United States)

    Zhang, Zijia; Elser, James J; Cease, Arianne J; Zhang, Ximei; Yu, Qiang; Han, Xingguo; Zhang, Guangming

    2014-01-01

    Nitrogen (N) and phosphorus (P) are important limiting nutrients for plant production and consumer performance in a variety of ecosystems. As a result, the N:P stoichiometry of herbivores has received increased attention in ecology. However, the mechanisms by which herbivores maintain N:P stoichiometric homeostasis are poorly understood. Here, using a field manipulation experiment we show that the grasshopper Oedaleus asiaticus maintains strong N:P stoichiometric homeostasis regardless of whether grasshoppers were reared at low or high density. Grasshoppers maintained homeostasis by increasing P excretion when eating plants with higher P contents. However, while grasshoppers also maintained constant body N contents, we found no changes in N excretion in response to changing plant N content over the range measured. These results suggest that O. asiaticus maintains P homeostasis primarily by changing P absorption and excretion rates, but that other mechanisms may be more important for regulating N homeostasis. Our findings improve our understanding of consumer-driven P recycling and may help in understanding the factors affecting plant-herbivore interactions and ecosystem processes in grasslands.

  19. Heat dosage and oviposition depth influence egg mortality of two common rangeland grasshopper species

    Science.gov (United States)

    Rangeland fire is a common naturally occurring event and management tool, with the amount and structure of biomass controlling transfer of heat belowground. Temperatures grasshopper eggs are exposed to during rangeland fires are mediated by species specific oviposition traits. This experiment examin...

  20. Densidad y estructura poblacional de Cebus capucinus curtus (Primates: Cebidae y Bradypus variegatus gorgon (Pilosa: Bradypodidae, en Isla Gorgona , Colombia

    Directory of Open Access Journals (Sweden)

    Mario Fernando Garcés-Restrepo

    2014-02-01

    Full Text Available En Isla Gorgona se registran dos subespecies endémicas de mamíferos arbóreos, el Mono capuchino de pecho blanco (Cebus capucinus curtus y el Perezoso de tres dedos de garganta marrón (Bradypus variegatus gorgon, especies importante para la conservación debido a su carácter endémico y papel ecológico como dispersores de semillas en el PNN Gorgona. En este trabajo se presenta información sobre la ecología poblacional de estas dos subespecies, utilizando el método de muestreo por distancia con transectos lineales para establecer la densidad, además se describió la estructura etaria general de cada población con base en los muestreos y observaciones directas. La densidad de C. capucinus curtus en isla Gorgona fue de 170,6 ind/km² (IC 95%=122,0-238,4 ind/km² mientras que para B. variegatus gorgon fue de 2,6 ind/km² (IC 95%=1,3-4,9 ind/km². El registro de densidad de C. capucinus curtus en isla Gorgona es el más alto para la especie en todo su rango de distribución geográfica, mientras que el de B. variegatus gorgon es el más bajo reportado para la especie. La alta densidad de C. capucinus curtus estaría relacionada con un efecto sinérgico entre la baja depredación natural y la continua disponibilidad de alimento, mientras que la baja densidad de B. variegatus gorgon estaría relacionada con la presión de caza realizada en el pasado, la baja tasa reproductiva de la especie y una pandemia ocurrida en el año 2005. Se recomienda el monitoreo constante de las poblaciones y estudios de salud poblacional para B. variegatus gorgon.

  1. Effects of the toxic benthic dinoflagellate Ostreopsis cf. ovata on fertilization and early development of the sea urchin Lytechinus variegatus.

    Science.gov (United States)

    Neves, Raquel A F; Contins, Mariana; Nascimento, Silvia M

    2018-04-01

    Blooms of the benthic dinoflagellate Ostreopsis cf. ovata have been recorded with increasing frequency, intensity and geographic distribution. This dinoflagellate produces potent toxins that may cause mortality of marine invertebrates. Adults of sea urchins are commonly affected by O. cf. ovata exposure with evidence of spines loss and high mortality during periods of high dinoflagellate abundances. Here, we report on the effects of the toxic dinoflagellate O. cf. ovata on fertilization and early development of the sea urchin Lytechinus variegatus, a key ecological herbivore. Lytechinus variegatus eggs and sperm were experimentally exposed to different concentrations of Ostreopsis cf. ovata (4, 40, 400, and 4000 cells ml -1 ) to test the hypothesis that fertilization success, embryonic and larval development of the sea urchin are negatively affected by the toxic dinoflagellate even at low abundances. Reduced fertilization, developmental failures, embryo and larval mortality, and occurrence of abnormal offspring were evident after exposure to O. cf. ovata. Fertilization decreased when gametes were exposed to high O. cf. ovata abundances (400 and 4000 cells ml -1 ), but just the exposure to the highest abundance significantly reduced fertilization success. Sea urchin early development was affected by O. cf. ovata in a dose-dependent way, high dinoflagellate abundances fully inhibited the early development of L. variegatus. Ostreopsis cf. ovata significantly increased the mortality of sea urchin eggs and embryos in the first hours of exposure (∼1-3 h), regardless of dinoflagellate abundance. Abundances of 400 and 4000 O. cf. ovata cells ml -1 induced significantly higher mortality on sea urchin initial stages in the first hours, and no egg or embryo was found in these treatments after 18 h of incubation. The early echinopluteus larva was only reached in the control and in treatments with low Ostreopsis cf. ovata abundances (4 and 40 cells ml -1 ). The

  2. Status assessment and conservation plan for the Grasshopper Sparrow (Ammodramus savannarum)

    Science.gov (United States)

    Ruth, Janet M.

    2015-01-01

    The Grasshopper Sparrow (Ammodramus savannarum) breeds in grassland habitats throughout much of the U.S., southern and southeastern Canada, and northern Mexico. Additional subspecies are resident in Central America, northern South America, and the Caribbean. It winters primarily in the coastal states of the southeastern U.S., southern portions of the southwestern states, and in Mexico, Central America, and the Caribbean. The species prefers relatively open grassland with intermediate grass height and density and patchy bare ground; because it is widely distributed across different grassland types in North America, it selects different vegetation structure and species composition depending on what is available. In the winter, they use a broader range of grassland habitats including open grasslands, as well as weedy fields and grasslands with woody vegetation. Analyses show significant range-wide population declines from the late 1960s through the present, primarily caused by habitat loss, degradation, and fragmentation. Grasshopper Sparrow is still a relatively common and broadly distributed species, but because of significant population declines and stakeholder concerns, the species is considered of conservation concern nationally and at the state level for numerous states. Many factors, often related to different grassland management practices (e.g., grazing, burning, mowing, management of shrub encroachment, etc.) throughout the species’ range, have impacts on Grasshopper Sparrow distribution, abundance, and reproduction and may represent limiting factors or threats given steep declines in this species’ population. Because of the concerns for this species, Grasshopper Sparrow has been identified as a focal species by the U.S. Fish and Wildlife Service (USFWS) and this Status Assessment and Conservation Plan for Grasshopper Sparrow has been developed. Through literature searches and input from stakeholders across its range, this plan presents information about

  3. [An evaluation of potential occurrence of grasshopper plague in Xianghuangqi grasslands of Inner Mongolia, North China].

    Science.gov (United States)

    Zhang, Hong-Yan; Zhang, Na; Chen, Xiao-Yan

    2012-01-01

    In this study, the key climatic factors in spawning, overwintering, and hatching periods of grasshopper were taken as the main factors to establish the climatic suitability index of potential occurrence of grasshopper (POG) in Inner Mongolia, and an evaluation was conducted on the climatic suitability of POG in Xianghuangqi County of Inner Mongolia in 2010. Based on the field investigation data collected in early and mid July 2010, seven relatively stable habitat factors including elevation, aspect, soil type, soil sand content, vegetation type, vegetation coverage, and land cover type were selected, and the habitat suitability for POG throughout the County was estimated by using fuzzy evaluation combining with 3S (GIS, RS, and GPS) technology. The POG ranks in 2010 were estimated by integrating the climatic and habitat suitability for POG. The simulated locations where grasshopper occurred were verified by the field investigation data in 2010, and the simulated areas infected by grasshopper were verified by historical data from 2001 to 2010. The results confirmed that the estimated POG ranks were reliable. The climatic suitability for POG was very homogeneous over the study area, and the vast majority of the study area was in the rank of "suitable". The spatial heterogeneity of the potential locations where the grasshopper might occur was mainly related to habitat factors. The highest POG rank was found at the locations with elevation 1300-1400 m, flat or aspect of east or south, typical chestnut soil, soil sand content 60%-80%, and vegetation coverage 30%-50% in temperate bunchgrass steppe.

  4. Predator-Prey Interactions are Context Dependent in a Grassland Plant-Grasshopper-Wolf Spider Food Chain.

    Science.gov (United States)

    Laws, Angela N; Joern, Anthony

    2015-06-01

    Species interactions are often context dependent, where outcomes vary in response to one or more environmental factors. It remains unclear how abiotic conditions like temperature combine with biotic factors such as consumer density or food quality to affect resource availability or influence species interactions. Using the large grasshopper Melanoplus bivittatus (Say) and a common wolf spider [Rabidosa rabida (Walkenaer)], we conducted manipulative field experiments in tallgrass prairie to examine how spider-grasshopper interactions respond to manipulations of temperature, grasshopper density, and food quality. Grasshopper survival was density dependent, as were the effects of spider presence and food quality in context-dependent ways. In high grasshopper density treatments, predation resulted in increased grasshopper survival, likely as a result of reduced intraspecific competition in the presence of spiders. Spiders had no effect on grasshopper survival when grasshoppers were stocked at low densities. Effects of the experimental treatments were often interdependent so that effects were only observed when examined together with other treatments. The occurrence of trophic cascades was context dependent, where the effects of food quality and spider presence varied with temperature under high-density treatments. Temperature weakly affected the impact of spider presence on M. bivittatus survivorship when all treatments were considered simultaneously, but different context-dependent responses to spider presence and food quality were observed among the three temperature treatments under high-density conditions. Our results indicate that context-dependent species interactions are common and highlight the importance of understanding how key biotic and abiotic factors combine to influence species interactions. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Assessment of microplastic toxicity to embryonic development of the sea urchin Lytechinus variegatus (Echinodermata: Echinoidea).

    Science.gov (United States)

    Nobre, C R; Santana, M F M; Maluf, A; Cortez, F S; Cesar, A; Pereira, C D S; Turra, A

    2015-03-15

    Apart from the physiological impacts on marine organisms caused by ingesting microplastics, the toxicity caused by substances leaching from these particles into the environment requires investigation. To understand this potential risk, we evaluated the toxicity of virgin (raw) and beach-stranded plastic pellets to the development of embryos of Lytechinus variegatus, simulating transfers of chemical compounds to interstitial water and water column by assays of pellet-water interface and elutriate, respectively. Both assays showed that virgin pellets had toxic effects, increasing anomalous embryonic development by 58.1% and 66.5%, respectively. The toxicity of stranded pellets was lower than virgin pellets, and was observed only for pellet-water interface assay. These results show that (i) plastic pellets act as a vector of pollutants, especially for plastic additives found on virgin particles; and that (ii) the toxicity of leached chemicals from pellets depends on the exposure pathway and on the environmental compartment in which pellets accumulate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Isolation Of Compounds Of Steroids Teripang Gamat (Stichopus variegatus With Various Types Of Solvents

    Directory of Open Access Journals (Sweden)

    Meydia Meydia

    2017-02-01

    Full Text Available AbstractSea cucumber is one of the fisheries commodity that has an important economic value. Generally is traded in dried form (beche-de-mer. One of thebioactive substances contained in sea cucumber is steroid compounds that serves as an aphrodisiac and sex reversal. The purpose of this study was to extract the steroid of the gamma sea cucumber by using three types of solvents (methanol, ethyl acetate and hexane and get the best solvent in producing the highest yield of the steroids. The study revealed that steroid of gamma sea cucumber (Stichopus variegatus dissolved completely ethyl acetate (semi-polar solvent during the first phase, second phase and the third phase of extraction. In the methanol (polar solvent steroids only dissolved in the first extraction phase, while using the hexane (non polar solvent steroid was undetectable. Fractionation by thin layer chromatography was obtained two fractions that identified as cholesterol (Rf = 0.96 and testosterone (Rf = 0.91.

  7. Endogenous lentivirus in Malayan colugo (Galeopterus variegatus), a close relative of primates.

    Science.gov (United States)

    Hron, Tomáš; Fábryová, Helena; Pačes, Jan; Elleder, Daniel

    2014-10-04

    A significant fraction of mammalian genomes is composed of endogenous retroviral (ERV) sequences that are formed by germline infiltration of various retroviruses. In contrast to other retroviral genera, lentiviruses only rarely form ERV copies. We performed a computational search aimed at identification of novel endogenous lentiviruses in vertebrate genomes. Using the in silico strategy, we have screened 104 publicly available vertebrate genomes for the presence of endogenous lentivirus sequences. In addition to the previously described cases, the search revealed the presence of endogenous lentivirus in the genome of Malayan colugo (Galeopterus variegatus). At least three complete copies of this virus, denoted ELVgv, were detected in the colugo genome, and approximately one hundred solo LTR sequences. The assembled consensus sequence of ELVgv had typical lentivirus genome organization including three predicted accessory genes. Phylogenetic analysis placed this virus as a distinct subgroup within the lentivirus genus. The time of insertion into the dermopteran lineage was estimated to be more than thirteen million years ago. We report the discovery of the first endogenous lentivirus in the mammalian order Dermoptera, which is a taxon close to the Primates. Lentiviruses have infiltrated the mammalian germline several times across millions of years. The colugo virus described here represents possibly the oldest documented endogenization event and its discovery can lead to new insights into lentivirus evolution. This is also the first report of an endogenous lentivirus in an Asian mammal, indicating a long-term presence of this retrovirus family in Asian continent.

  8. Intraspecific variation in 137Cs activity concentration in sporocarps of Suillus variegatus in seven Swedish populations

    International Nuclear Information System (INIS)

    Dahlberg, Anders; Nikolova, Ivanka; Johanson, K.-J.

    1997-01-01

    Following the Chernobyl accident in 1986, sporocarps of Suillus variegatus in Sweden showed a large amount of individual variation in concentration of 137 Cs activity. Our aim was to determine the degrees to which this variability in sporocarp 137 Cs levels could be explained by differences between (i) local populations, (ii) fungal genets and (iii) locations within genets. Five populations in a 100-yr-old Scots pine forest, located within a 1 km 2 area, and two populations in Scots pine/Norway spruce forest, located 40 km north-west of Uppsala, were investigated. In total, 154 sporocarps were analysed to determine their 137 Cs content. Of these, the genetic affiliations of 86 were successfully characterized using somatic incompatibility reactions. Twenty-six genets were found which, on average, consisted of 6.5 sporocarps. The genets averaged 7.5 m in size, measured as the length between the most distant sporocarps. The mean sporocarp 137 Cs level was 67.1 ± 2.8 kBq kgsup(-1) D.W. (range between 13.6 and 182). According to analyses of variance, within-population variation accounted for 60% of the total variation in 137 Cs levels, while 40% was ascribed to variation among populations. Within a population, 137 Cs levels did not generally differ significantly between genets. Plausible reasons for intraspecific variation in radiocaesium content in sporocarps are discussed. (author)

  9. Plant functional traits reveal the relative contribution of habitat and food preferences to the diet of grasshoppers.

    Science.gov (United States)

    Ibanez, Sébastien; Manneville, Olivier; Miquel, Christian; Taberlet, Pierre; Valentini, Alice; Aubert, Serge; Coissac, Eric; Colace, Marie-Pascale; Duparc, Quentin; Lavorel, Sandra; Moretti, Marco

    2013-12-01

    Food preferences and food availability are two major determinants of the diet of generalist herbivores and of their spatial distribution. How do these factors interact and eventually lead to diet differentiation in co-occurring herbivores? We quantified the diet of four grasshopper species co-occurring in subalpine grasslands using DNA barcoding of the plants contained in the faeces of individuals sampled in the field. The food preferences of each grasshopper species were assessed by a choice (cafeteria) experiment from among 24 plant species common in five grassland plots, in which the four grasshoppers were collected, while the habitat was described by the relative abundance of plant species in the grassland plots. Plant species were characterised by their leaf economics spectrum (LES), quantifying their nutrient vs. structural tissue content. The grasshoppers' diet, described by the mean LES of the plants eaten, could be explained by their plant preferences but not by the available plants in their habitat. The diet differed significantly across four grasshopper species pairs out of six, which validates food preferences assessed in standardised conditions as indicators for diet partitioning in nature. In contrast, variation of the functional diversity (FD) for LES in the diet was mostly correlated to the FD of the available plants in the habitat, suggesting that diet mixing depends on the environment and is not an intrinsic property of the grasshopper species. This study sheds light on the mechanisms determining the feeding niche of herbivores, showing that food preferences influence niche position whereas habitat diversity affects niche breadth.

  10. Effects of Altered Seasonality of Precipitation on Grass Production and Grasshopper Performance in a Northern Mixed Prairie.

    Science.gov (United States)

    Branson, David H

    2017-06-01

    Climatic changes are leading to differing patterns and timing of precipitation in grassland ecosystems, with the seasonal timing of precipitation affecting plant biomass and plant composition. No previous studies have examined how drought seasonality affects grasshopper performance and the impact of herbivory on vegetation. We modified seasonal patterns of precipitation and grasshopper density in a manipulative experiment to examine if seasonality of drought combined with herbivory affected plant biomass, nitrogen content, and grasshopper performance. Grass biomass was affected by both precipitation and grasshopper density treatments, while nitrogen content of grass was higher with early-season drought. Proportional survival was negatively affected by initial density, while survival was higher with early drought than with full-season drought. Drought timing affected the outcome, with early summer drought increasing grass nitrogen content and grasshopper survival, while season-long and late-season drought did not. The results support arguments that our knowledge of plant responses to seasonal short-term variation in climate is limited and illustrate the importance of experiments manipulating precipitation phenology. The results confirm that understanding the season of drought is critical for predicting grasshopper population dynamics, as extreme early summer drought may be required to strongly affect Melanoplus sanguinipes (F.) performance. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

  11. Effects of cadmium on hypoxia-induced expression of hemoglobin and erythropoietin in larval sheepshead minnow, Cyprinodon variegatus

    Energy Technology Data Exchange (ETDEWEB)

    Dangre, A.J.; Manning, S. [Department of Coastal Sciences, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564 (United States); Brouwer, M., E-mail: marius.brouwer@usm.edu [Department of Coastal Sciences, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564 (United States)

    2010-08-15

    Hypoxia and toxic metals are two common stressors found in the estuarine environment. To date little information is available on the combined effects of these stressors on early larval development in fish. We investigated the effect of cadmium and hypoxia exposure alone as well in combination on larval Cyprinodon variegatus. The LC{sub 10} for cadmium was determined to be 0.3 ppm in a 96 h acute exposure. This concentration was used in all studies. Cadmium in larvae increased significantly with exposure time (1, 3, 5 and 7 days post-hatch). The increase was proportional to body weight and not affected by hypoxia. Cadmium responsive genes were identified by suppression subtractive hybridization (SSH) in Cyprinodonvariegatus larvae after exposure to cadmium for 1, 3, 5 and 7 days. We obtained over 700 sequences from the cadmium cDNA library. Blast search of ESTs suggested that cadmium modulates multiple physiological processes. Pertinent to this study, cadmium was found to down-regulate both embryonic {alpha} and {beta} globin, which are expressed in erythrocytes generated during the first, or primitive, wave of erythropoiesis in teleosts. Hemoglobin (Hb) and erythropoietin (Epo) (the hormone that promotes red blood cell production) are known hypoxia-inducible genes. To explore the possibility that cadmium might offset the hypoxia-induced expression of Hb and Epo, we investigated the expression of both genes following hypoxia, cadmium and combined exposures for 1, 3, 5 and 7 days post-hatch. Since Epo had not yet been identified in C. variegatus we first successfully cloned a partial coding sequence of the C. variegatus hormone. Subsequent studies revealed that expression levels of Hb and Epo remained unchanged in the normoxic controls during the time course of the study. Hypoxia increased Epo expression relative to normoxic controls, on days 3, 5 and 7, while cadmium in hypoxia inhibited the increase. Only the changes on days 5 and 7 were statistically significant

  12. Comparison of elliptical and spherical mirrors for the grasshopper monochromators at SSRL

    International Nuclear Information System (INIS)

    Waldhauer, A.P.

    1989-01-01

    A comparison of the performance of a spherical and elliptical mirror in the grasshopper monochromator is presented. The problem was studied by ray tracing and then tested using visible (λ=633 nm) laser light. Calculations using ideal optics yield an improvement in flux by a factor of up to 2.7, while tests with visible light show an increase by a factor of 5 because the old spherical mirror is compared to a new, perfect elliptical one. The FWHM of the measured focus is 90 μm with a spherical mirror, and 25 μm with an elliptical one. Elliptical mirrors have been acquired and are now being installed in the two grasshoppers at SSRL

  13. Characterization of the mitochondrial genome of the montane grasshopper, Qinlingacris elaeodes (Orthoptera: Catantopidae).

    Science.gov (United States)

    Li, Ran; Jiang, Guo-Fang; Liang, Ai-Ping; Zhong, Xin-Tong; Liu, Ying

    2016-05-01

    Qinlingacris elaeodes is the dominant grasshopper at an altitude of 3000 meters and above, and is a representative species of the genus Qinlingacris endemic to China. The sequenced mitochondrial genome of this grasshopper is 14,818 bp in length, including 13 protein-coding genes (ND1-6, COI-III, ATP6, ATP8, ND4L, CTYB), 21 transfer RNAs, and 2 ribosomal RNAs (12S and 16S). The orientation and gene order of these genes are identical to those found in the putative ancestral insect mitogenome. The 13 PCGs start with a typical ATN codon as their start codons. The usual TAA and TAG termination codons are found for 12 PCGs. However, the ND5 gene has an incomplete termination codon (T).

  14. The neuroblast of the grasshopper embryo as a new mutagen test system. Pt. 1

    International Nuclear Information System (INIS)

    Liang, J.C.; Gaulden, M.E.

    1982-01-01

    The neuroblasts of the grasshopper embryo (Chortophaga viridifasciata De Geer) are being studied to determine their suitability for detecting environmental clastogens (chromosome-breaking agents). They are very sensitive to the induction of chromosome breakage by radiation in viro. Their sensitvity, 0.011 break/cell/R, is 4-5 times higher than pollen mother cells of Tradescantia (micronuclei), 10 times higher than either human lymphocytes or Chinese hamster cells (metaphase chromosome aberrations), and 15 times higher than mouse erythroblasts (micronuclei). Furthermore, they have no spontaneous chromosome breakage, which facilitates the detection of agents that break chromosomes. The present study shows that Chortophaga embryos maintain normal mitotic activity in vitro for 5 cell cycles at 38 0 C (20 h), and that neuroblasts of embryos grown in vitro have the same radiosensitivity as those of embryos in vivo. Thus in vitro exposure of grasshopper embryos is a promising method for obtaining data on the response of neuroblasts to chemical clastogens. (orig.)

  15. Physical mapping of the Period gene on meiotic chromosomes of South American grasshoppers (Acridomorpha, Orthoptera).

    Science.gov (United States)

    Souza, T E; Oliveira, D L; Santos, J F; Rieger, T T

    2014-12-19

    The single-copy gene Period was located in five grasshopper species belonging to the Acridomorpha group through permanent in situ hybridization (PISH). The mapping revealed one copy of this gene in the L1 chromosome pair in Ommexecha virens, Xyleus discoideus angulatus, Tropidacris collaris, Schistocerca pallens, and Stiphra robusta. A possible second copy was mapped on the L2 chromosome pair in S. robusta, which should be confirmed by further studies. Except for the latter case, the chromosomal position of the Period gene was highly conserved among the four families studied. The S. robusta karyotype also differs from the others both in chromosome number and morphology. The position conservation of the single-copy gene Period contrasts with the location diversification of multigene families in these species. The localization of single-copy genes by PISH can provide new insights about the genomic content and chromosomal evolution of grasshoppers and others insects.

  16. Neuroblast of the grasshopper embryo as a new mutagen test system. Pt. 1. In vitro radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Liang, J C; Gaulden, M E [Texas Univ., Dallas (USA). Dept. of Radiology

    1982-04-01

    The neuroblasts of the grasshopper embryo (Chortophaga viridifasciata De Geer) are being studied to determine their suitability for detecting environmental clastogens (chromosome-breaking agents). They are very sensitive to the induction of chromosome breakage by radiation in vitro. Their sensitvity, 0.011 break/cell/R, is 4-5 times higher than pollen mother cells of Tradescantia (micronuclei), 10 times higher than either human lymphocytes or Chinese hamster cells (metaphase chromosome aberrations), and 15 times higher than mouse erythroblasts (micronuclei). Furthermore, they have no spontaneous chromosome breakage, which facilitates the detection of agents that break chromosomes. The present study shows that Chortophaga embryos maintain normal mitotic activity in vitro for 5 cell cycles at 38/sup 0/C (20 h), and that neuroblasts of embryos grown in vitro have the same radiosensitivity as those of embryos in vivo. Thus in vitro exposure of grasshopper embryos is a promising method for obtaining data on the response of neuroblasts to chemical clastogens.

  17. Reproduction-related sound production of grasshoppers regulated by internal state and actual sensory environment

    Directory of Open Access Journals (Sweden)

    Ralf eHeinrich

    2012-06-01

    Full Text Available The interplay of neural and hormonal mechanisms activated by entero- and exteroreceptors biases the selection of actions by decision making neuronal circuits. The reproductive behaviour of acoustically communicating grasshoppers, which is regulated by short-term neural and longer-term hormonal mechanisms, has frequently been used to study the cellular and physiological processes that select particular actions from the species-specific repertoire of behaviours. Various grasshoppers communicate with species- and situation-specific songs in order to attract and court mating partners, to signal reproductive readiness or to fend off competitors. Selection and coordination of type, intensity and timing of sound signals is mediated by the central complex, a highly structured brain neuropil known to integrate multimodal pre-processed sensory information by a large number of chemical messengers. In addition, reproductive activity including sound production critically depends on maturation, previous mating experience and oviposition cycles. In this regard, juvenile hormone released from the corpora allata has been identified as a decisive hormonal signal necessary to establish reproductive motivation in grasshopper females. Both regulatory systems, the central complex mediating short-term regulation and the corpora allata mediating longer-term regulation of reproduction related sound production mutually influence each other’s activity in order to generate a coherent state of excitation that promotes or suppresses reproductive behaviour in respective appropriate or inappropriate situations.This review summarizes our current knowledge about extrinsic and intrinsic factors that influence grasshopper reproductive motivation, their representation in the nervous system and their integrative processing that mediates the initiation or suppression of reproductive behaviors.

  18. On the origin of grasshopper oviposition behavior: structural homology in pregenital and genital motor systems.

    Science.gov (United States)

    Thompson, Karen J; Jones, Alaine D; Miller, Sandra A

    2014-01-01

    In female grasshoppers, oviposition is a highly specialized behavior involving a rhythm-generating neural circuit, the oviposition central pattern generator, unusual abdominal appendages, and dedicated muscles. This study of Schistocerca americana (Drury) grasshoppers was undertaken to determine whether the simpler pregenital abdominal segments, which do not contain ovipositor appendages, share common features with the genital segment, suggesting a roadmap for the genesis of oviposition behavior. Our study revealed that although 5 of the standard pregenital body wall muscles were missing in the female genital segment, homologous lateral nerves were, indeed, present and served 4 ovipositor muscles. Retrograde labeling of the corresponding pregenital nerve branches in male and female grasshoppers revealed motor neurons, dorsal unpaired median neurons, and common inhibitor neurons which appear to be structural homologues of those filled from ovipositor muscles. Some pregenital motor neurons displayed pronounced contralateral neurites; in contrast, some ovipositor motor neurons were exclusively ipsilateral. Strong evidence of structural homology was also obtained for pregenital and ovipositor skeletal muscles supplied by the identified neurons and of the pregenital and ovipositor skeletons. For example, transient embryonic segmental appendages were maintained in the female genital segments, giving rise to ovipositor valves, but were lost in pregenital abdominal segments. Significant proportional differences in sternal apodemes and plates were observed, which partially obscure the similarities between the pregenital and genital skeletons. Other changes in reorganization included genital muscles that displayed adult hypertrophy, 1 genital muscle that appeared to represent 2 fused pregenital muscles, and the insertion points of 2 ovipositor muscles that appeared to have been relocated. Together, the comparisons support the idea that the oviposition behavior of genital

  19. Reproduction-Related Sound Production of Grasshoppers Regulated by Internal State and Actual Sensory Environment

    Science.gov (United States)

    Heinrich, Ralf; Kunst, Michael; Wirmer, Andrea

    2012-01-01

    The interplay of neural and hormonal mechanisms activated by entero- and extero-receptors biases the selection of actions by decision making neuronal circuits. The reproductive behavior of acoustically communicating grasshoppers, which is regulated by short-term neural and longer-term hormonal mechanisms, has frequently been used to study the cellular and physiological processes that select particular actions from the species-specific repertoire of behaviors. Various grasshoppers communicate with species- and situation-specific songs in order to attract and court mating partners, to signal reproductive readiness, or to fend off competitors. Selection and coordination of type, intensity, and timing of sound signals is mediated by the central complex, a highly structured brain neuropil known to integrate multimodal pre-processed sensory information by a large number of chemical messengers. In addition, reproductive activity including sound production critically depends on maturation, previous mating experience, and oviposition cycles. In this regard, juvenile hormone released from the corpora allata has been identified as a decisive hormonal signal necessary to establish reproductive motivation in grasshopper females. Both regulatory systems, the central complex mediating short-term regulation and the corpora allata mediating longer-term regulation of reproduction-related sound production mutually influence each other’s activity in order to generate a coherent state of excitation that promotes or suppresses reproductive behavior in respective appropriate or inappropriate situations. This review summarizes our current knowledge about extrinsic and intrinsic factors that influence grasshopper reproductive motivation, their representation in the nervous system and their integrative processing that mediates the initiation or suppression of reproductive behaviors. PMID:22737107

  20. High plant species diversity indirectly mitigates CO 2- and N-induced effects on grasshopper growth

    Science.gov (United States)

    Strengbom, Joachim; Reich, Peter B.; Ritchie, Mark E.

    2008-09-01

    We examined how elevated atmospheric [CO 2] and higher rate of nitrogen (N) input may influence grasshopper growth by changing food plant quality and how such effects may be modified by species diversity of the plant community. We reared grasshopper nymphs ( Melanoplus femurrubrum) on Poa pratensis from field-grown monocultures or polycultures (16 species) that were subjected to either ambient or elevated levels of CO 2 and N. Grasshopper growth rate was higher on P. pratensis leaves grown in monocultures than in polycultures, higher on P. pratensis grown under elevated than under ambient [CO 2], and higher on P. pratensis grown under elevated than under ambient [N]. The higher growth rate observed on P. pratensis exposed to elevated [CO 2] was, however, less pronounced for polyculture- than monoculture-grown P. pratensis. Growth rate of the grasshoppers was positively correlated with leaf [N], [C], and concentration of soluble carbohydrates + lipids. Concentration of non-structural carbohydrates + lipids was higher in leaves grown under elevated than under ambient [CO 2], and the difference between P. pratensis grown under ambient and elevated [CO 2] was greater for monoculture- than polyculture-grown P. pratensis. In addition, leaf N concentration was higher in P. pratensis grown in monocultures than in polycultures, suggesting that plant species richness, indirectly, may influence insect performance by changed nutritional value of the plants. Because we found interactive effects between all factors included ([CO 2], [N], and plant species diversity), our results suggest that these parameters may influence plant-insect interactions in a complex way that is not predictable from the sum of single factor manipulations.

  1. Nitrogen limitation and life history adaptation in the grasshopper "Omocestus viridulus"

    OpenAIRE

    Berner, Daniel

    2005-01-01

    The role of plant-mediated constraints to herbivore populations in terrestrial ecosystems remains relatively poorly understood. One aim of this study was therefore to explore the effects of low host plant nitrogen (N) content on herbivore performance and feeding behaviour, and thereby to evaluate the utility of the N limitation and nutrient balance concepts. The grass-feeding grasshopper Omocestus viridulus (Orthoptera: Acrididae) provided a well-suited model system as the species exhibits hi...

  2. Circadian rhythms in blood pressure in free-ranging three-toed sloths (Bradypus variegatus

    Directory of Open Access Journals (Sweden)

    Duarte D.P.F.

    2003-01-01

    Full Text Available Blood pressure (BP profiles were monitored in nine free-ranging sloths (Bradypus variegatus by coupling one common carotid artery to a BP telemetry transmitter. Animals moved freely in an isolated and temperature-controlled room (24ºC with 12/12-h artificial light-dark cycles and behaviors were observed during resting, eating and moving. Systolic (SBP and diastolic (DBP blood pressures were sampled for 1 min every 15 min for 24 h. BP rhythm over 24 h was analyzed by the cosinor method and the mesor, amplitude, acrophase and percent rhythm were calculated. A total of 764 measurements were made in the light cycle and 721 in the dark cycle. Twenty-four-hour values (mean ± SD were obtained for SBP (121 ± 22 mmHg, DBP (86 ± 17 mmHg, mean BP (MBP, 98 ± 18 mmHg and heart rate (73 ± 16 bpm. The SBP, DBP and MBP were significantly higher (unpaired Student t-test during the light period (125 ± 21, 88 ± 15 and 100 ± 17 mmHg, respectively than during the dark period (120 ± 21, 85 ± 17 and 97 ± 17 mmHg, respectively and the acrophase occurred between 16:00 and 17:45 h. This circadian variation is similar to that observed in cats, dogs and marmosets. The BP decreased during "behavioral sleep" (MBP down from 110 ± 19 to 90 ± 19 mmHg at 21:00 to 8:00 h. Both feeding and moving induced an increase in MBP (96 ± 17 to 119 ± 17 mmHg at 17:00 h and 97 ± 19 to 105 ± 12 mmHg at 15:00 h, respectively. The results show that conscious sloths present biphasic circadian fluctuations in BP levels, which are higher during the light period and are mainly synchronized with feeding.

  3. Short-Term Dynamics of Behavioral Thermoregulation by Adults of the Grasshopper Melanoplus sanguinipes

    Science.gov (United States)

    O'Neill, Kevin M.; Rolston, Marni G.

    2007-01-01

    The short-term behavioral responses of adult grasshoppers, Melanoplus sanguinipes (F.) (Orthoptera: Acrididae), were examined after they experienced changes in microclimate when beingforced to change positions in their habitat. It was also determined if and when behavioral tactics allowed adults to achieve body temperatures within their preferred range. The preferred or set-point range, here taken as the interquartile range of temperatures selected on a laboratory thermal gradient, was estimated to be 37.4–40.5°C. In the field, adults progressed through a relatively consistent daily sequence of behaviors, basking on the soil early in the day, but moving onto vegetation as temperatures increased. Although basking allowed grasshoppers to maximize body temperature within the available range, as much as 7°C in excess of air temperature, they could not attain preferred body temperatures until soil surface temperatures reach about 35°C. Basking was more effective in grazed than ungrazed pastures due to a lower degree of shading of the soil surface. As soil surface temperatures exceeded 35°C, grasshoppers could achieve body temperatures within the preferred range by moving to the appropriate height on vegetation. These results illustrate the advantage of assessing behavior in the field in relation to preferred body temperatures determined in the laboratory. PMID:20302531

  4. Diet alters performance and transcription patterns in Oedaleus asiaticus (Orthoptera: Acrididae) grasshoppers.

    Science.gov (United States)

    Huang, Xunbing; Whitman, Douglas W; Ma, Jingchuan; McNeill, Mark Richard; Zhang, Zehua

    2017-01-01

    We reared Oedaleus asiaticus grasshoppers under four different single-plant diets to examine the relationships among diet, performance, stress, and transcription patterns. Grasshoppers fed only Artemisia frigida (Asteraceae) were stressed, as indicated by their lower growth, size, development, and survival, in comparison to grasshoppers fed on any of three grasses, Cleistogenes squarrosa, Leymus chinensis, or Stipa krylovii (all Poaceae). We then used transcriptome analysis to examine how gene expression levels in O. asiaticus were altered by feeding on these diets. Nymphs fed A. frigida had the largest variation in gene expression profiles with a total of 299 genes significantly up- or down-regulated compared to those feeding on the three grasses: down-regulated genes included those involved in cuticle biosynthesis, DNA replication, biosynthesis and metabolism of nutrition. The up-regulated genes included stress-resistant and detoxifying enzymes. GO and KEGG enrichment analysis also showed that feeding on A. frigida could down-regulate biosynthesis and metabolism related pathways, and up-regulate stress-resistant and detoxification terms and pathways. Our results show that diet significantly altered gene-expression, and that unfavorable, stressful diets induce more transcriptional changes than favorable diets. Altered gene-expression represents phenotypic plasticity, and many such changes appear to be evolved, adaptive responses. The ease and regularity by which individuals shift phenotypes via altered transcription suggests that populations consist not of similar, fixed phenotypes, but of a collection of ever-changing, divergent phenotypes.

  5. Grasshopper sparrow reproductive success and habitat use on reclaimed surface mines varies by age of reclamation

    Science.gov (United States)

    Wood, Petra; Ammer, Frank K.

    2015-01-01

    We studied 3 mountaintop mining–valley fill (MTMVF) complexes in southern West Virginia, USA to examine grasshopper sparrow (Ammodramus savannarum pratensis) demographic response to different age classes of mine land reclamation. For 71 nests monitored during the 2001–2002 breeding seasons, overall nest success (36%) was within the range of nest success rates previously reported for this species, but it was highest on more recently reclaimed sites (56%). Nest density and clutch size did not differ (P > 0.30) among reclamation age classes, whereas number of fledglings was greater (P = 0.01) on more recently reclaimed sites. We measured vegetation variables at 70 nest subplots and at 96 systematic subplots to compare nest vegetation with vegetation available on the plots. We found that nests occurred in areas with more bare ground near the nest, greater vegetation height–density surrounding the nest site, lower grass height, and fewer woody stems, similar to previous studies. As postreclamation age increased, vegetation height–density and maximum grass height increased, and sericea (Lespedeza cuneata) became more dominant. Nest success declined with increasing vegetation height–density at the nest. The grasslands available on these reclaimed mine complexes are of sufficient quality to support breeding populations of grasshopper sparrows, but nest success decreased on the older reclaimed areas. Without active management, grasslands on reclaimed MTMVF mines become less suitable for nesting grasshopper sparrows about 10 years after reclamation.

  6. A conserved plan for wiring up the fan-shaped body in the grasshopper and Drosophila.

    Science.gov (United States)

    Boyan, George; Liu, Yu; Khalsa, Sat Kartar; Hartenstein, Volker

    2017-07-01

    The central complex comprises an elaborate system of modular neuropils which mediate spatial orientation and sensory-motor integration in insects such as the grasshopper and Drosophila. The neuroarchitecture of the largest of these modules, the fan-shaped body, is characterized by its stereotypic set of decussating fiber bundles. These are generated during development by axons from four homologous protocerebral lineages which enter the commissural system and subsequently decussate at stereotypic locations across the brain midline. Since the commissural organization prior to fan-shaped body formation has not been previously analyzed in either species, it was not clear how the decussating bundles relate to individual lineages, or if the projection pattern is conserved across species. In this study, we trace the axonal projections from the homologous central complex lineages into the commissural system of the embryonic and larval brains of both the grasshopper and Drosophila. Projections into the primordial commissures of both species are found to be lineage-specific and allow putatively equivalent fascicles to be identified. Comparison of the projection pattern before and after the commencement of axon decussation in both species reveals that equivalent commissural fascicles are involved in generating the columnar neuroarchitecture of the fan-shaped body. Further, the tract-specific columns in both the grasshopper and Drosophila can be shown to contain axons from identical combinations of central complex lineages, suggesting that this columnar neuroarchitecture is also conserved.

  7. Reduced predation risk for melanistic pygmy grasshoppers in post-fire environments

    Science.gov (United States)

    Karpestam, Einat; Merilaita, Sami; Forsman, Anders

    2012-01-01

    The existence of melanistic (black) color forms in many species represents interesting model systems that have played important roles for our understanding of selective processes, evolution of adaptations, and the maintenance of variation. A recent study reported on rapid evolutionary shifts in frequencies of the melanistic forms in replicated populations of Tetrix subulata pygmy grasshoppers; the incidence of the melanistic form was higher in recently burned areas with backgrounds blackened by fire than in nonburned areas, and it declined over time in postfire environments. Here, we tested the hypothesis that the frequency shifts of the black color variant were driven, at least in part, by changes in the selective regime imposed by visual predators. To study detectability of the melanistic form, we presented human “predators” with images of black grasshoppers and samples of the natural habitat on computer screens. We demonstrate that the protective value of black coloration differs between burnt and nonburnt environments and gradually increases in habitats that have been more blackened by fire. These findings support the notion that a black color pattern provides improved protection from visually oriented predators against blackened backgrounds and implicate camouflage and predation as important drivers of fire melanism in pygmy grasshoppers. PMID:23139879

  8. The effectiveness of common thermo-regulatory behaviours in a cool temperate grasshopper.

    Science.gov (United States)

    Harris, Rebecca M B; McQuillan, Peter; Hughes, Lesley

    2015-08-01

    Behavioural thermoregulation has the potential to alleviate the short-term impacts of climate change on some small ectotherms, without the need for changes to species distributions or genetic adaptation. We illustrate this by measuring the effect of behaviour in a cool temperate species of grasshopper (Phaulacridium vittatum) over a range of spatial and temporal scales in laboratory and natural field experiments. Microhabitat selection at the site scale was tested in free-ranging grasshoppers and related to changing thermal quality over a daily period. Artificial warming experiments were then used to measure the temperature at which common thermoregulatory behaviours are initiated and the subsequent reductions in body temperature. Behavioural means such as timing of activity, choice of substrates with optimum surface temperatures, shade seeking and postural adjustments (e.g. stilting, vertical orientation) were found to be highly effective at maintaining preferred body temperature. The maximum voluntarily tolerated temperature (MVT) was determined to be 44°C±0.4°C, indicating the upper bounds of thermal flexibility in this species. Behavioural thermoregulation effectively enables small ectotherms to regulate exposure to changing environmental temperatures and utilize the spatially and temporally heterogeneous environments they occupy. Species such as the wingless grasshopper, although adapted to cool temperate conditions, are likely to be well equipped to respond successfully to coarse scale climate change. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Genome size variation affects song attractiveness in grasshoppers: evidence for sexual selection against large genomes.

    Science.gov (United States)

    Schielzeth, Holger; Streitner, Corinna; Lampe, Ulrike; Franzke, Alexandra; Reinhold, Klaus

    2014-12-01

    Genome size is largely uncorrelated to organismal complexity and adaptive scenarios. Genetic drift as well as intragenomic conflict have been put forward to explain this observation. We here study the impact of genome size on sexual attractiveness in the bow-winged grasshopper Chorthippus biguttulus. Grasshoppers show particularly large variation in genome size due to the high prevalence of supernumerary chromosomes that are considered (mildly) selfish, as evidenced by non-Mendelian inheritance and fitness costs if present in high numbers. We ranked male grasshoppers by song characteristics that are known to affect female preferences in this species and scored genome sizes of attractive and unattractive individuals from the extremes of this distribution. We find that attractive singers have significantly smaller genomes, demonstrating that genome size is reflected in male courtship songs and that females prefer songs of males with small genomes. Such a genome size dependent mate preference effectively selects against selfish genetic elements that tend to increase genome size. The data therefore provide a novel example of how sexual selection can reinforce natural selection and can act as an agent in an intragenomic arms race. Furthermore, our findings indicate an underappreciated route of how choosy females could gain indirect benefits. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  10. Effects of zinc and female aging on nymphal life history in a grasshopper from polluted sites.

    Science.gov (United States)

    Augustyniak, Maria; Babczyńska, Agnieszka; Kozłowski, Michał; Sawczyn, Tomasz; Augustyniak, Michał

    2008-01-01

    Insect reproduction is influenced by various factors, including food quality and quantity, temperature, population density and female age. Contamination, including heavy metals, may disturb reproductive processes. The aim of this work was to assess interactions between effects of aging in female Chorthippus brunneus and environmental pollution on their reproduction measured in number of laid eggs. We also compared basic developmental parameters (number of hatchlings, body mass, embryonic developmental rate) in grasshopper nymphs additionally exposed to zinc during diapause. Aging grasshoppers from heavily polluted areas (Olkusz and Szopienice) lay significantly fewer eggs than insects from the reference site (Pilica). Zinc application caused the decrease in hatching success and duration of embryogenesis in insects from each site. This suggests a cumulative effect of female age, pollutants and additional stressing factors. The intensity of this process differed between populations. In insects from the reference site, it was shown in a moderate degree. In insects from Szopienice, an additional stressor exerted a weaker effect than in insects from Pilica. In grasshoppers from Olkusz, we found the strongest decrease of hatching percentage and increase in duration of embryogenesis after zinc intoxication. This may indicate that the population from Olkusz exists at the limit of its energetic abilities.

  11. Endocrine modulation and toxic effects of two commonly used UV screens on the aquatic invertebrates Potamopyrgus antipodarum and Lumbriculus variegatus

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Claudia [Johann Wolfgang Goethe-University, Department Aquatic Ecotoxicology, Siesmayerstrasse 70, 60323 Frankfurt (Germany)], E-mail: claudia.schmitt@ua.ac.be; Oetken, Matthias; Dittberner, Olaf; Wagner, Martin; Oehlmann, Joerg [Johann Wolfgang Goethe-University, Department Aquatic Ecotoxicology, Siesmayerstrasse 70, 60323 Frankfurt (Germany)

    2008-03-15

    The two UV screens 3-benzylidene-camphor (3-BC) and 3-(4'-methylbenzylidene)-camphor (4-MBC) were tested regarding their toxicity and estrogenic activity. The Yeast Estrogen Screen (YES) and two sediment assays with the freshwater invertebrates Lumbriculus variegatus and Potamopyrgus antipodarum were performed. In the YES, both substances activated the human estrogen receptor {alpha} with EC{sub 50} values of 44.2 {mu}M for 3-BC and 44.3 {mu}M for 4-MBC, whereby 4-MBC attained only 8% of the maximal response of 17{beta}-estradiol. For P. antipodarum embryo production increased after exposure to both substances (EC{sub 50} of 4.60 {mu}M 4-MBC = 1.17 mg kg{sup -1} dw) while mortality increased at high concentrations. The reproduction of L. variegatus was decreased by 3-BC with an EC{sub 50} of 5.95 {mu}M (=1.43 mg kg{sup -1} dw) and also by 4-MBC, where no EC{sub 50} could be calculated. While reproduction decreased, the worms' weight increased after exposure to 3-BC with an EC{sub 50} of 26.9 {mu}M (= 6.46 mg kg{sup -1} dw), hence the total biomass remained unaffected. - UV screens can have a significant impact on reproduction and development of aquatic invertebrates.

  12. Bioaccumulation of glyphosate and its formulation Roundup Ultra in Lumbriculus variegatus and its effects on biotransformation and antioxidant enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Contardo-Jara, Valeska [Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department of Inland Fisheries, Biochemical Regulation, Mueggelseedamm 301, 12587 Berlin (Germany)], E-mail: contardo@igb-berlin.de; Klingelmann, Eva [Technische Universitaet Berlin/Berlin Institute of Technology, Department of Ecology, Chair of Soil Protection, Salzufer 12, 10587 Berlin (Germany)], E-mail: eva.klingelmann@TU-Berlin.de; Wiegand, Claudia [Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department of Inland Fisheries, Biochemical Regulation, Mueggelseedamm 301, 12587 Berlin (Germany); Humboldt University Berlin, Faculty of Biology, Unter den Linden 6, 10099 Berlin (Germany)], E-mail: cwiegand@igb-berlin.de

    2009-01-15

    The bioaccumulation potential of glyphosate and the formulation Roundup Ultra, as well as possible effects on biotransformation and antioxidant enzymes in Lumbriculus variegatus were compared by four days exposure to concentrations between 0.05 and 5 mg L{sup -1} pure glyphosate and its formulation. Bioaccumulation was determined using {sup 14}C labeled glyphosate. The bioaccumulation factor (BCF) varied between 1.4 and 5.9 for the different concentrations, and was higher than estimated from log P{sub ow}. Glyphosate and its surfactant POEA caused elevation of biotransformation enzyme soluble glutathione S-transferase at non-toxic concentrations. Membrane bound glutathione S-transferase activity was significantly elevated in Roundup Ultra exposed worms, compared to treatment with equal glyphosate concentrations, but did not significantly differ from the control. Antioxidant enzyme superoxide dismutase was significantly increased by glyphosate but in particular by Roundup Ultra exposure indicating oxidative stress. The results show that the formulation Roundup Ultra is of more ecotoxicological relevance than the glyphosate itself. - Roundup Ultra is of more ecotoxicological relevance than the active ingredient, glyphosate, to Lumbriculus variegatus regarding accumulation potential and enzymatic responses.

  13. Bioaccumulation of glyphosate and its formulation Roundup Ultra in Lumbriculus variegatus and its effects on biotransformation and antioxidant enzymes

    International Nuclear Information System (INIS)

    Contardo-Jara, Valeska; Klingelmann, Eva; Wiegand, Claudia

    2009-01-01

    The bioaccumulation potential of glyphosate and the formulation Roundup Ultra, as well as possible effects on biotransformation and antioxidant enzymes in Lumbriculus variegatus were compared by four days exposure to concentrations between 0.05 and 5 mg L -1 pure glyphosate and its formulation. Bioaccumulation was determined using 14 C labeled glyphosate. The bioaccumulation factor (BCF) varied between 1.4 and 5.9 for the different concentrations, and was higher than estimated from log P ow . Glyphosate and its surfactant POEA caused elevation of biotransformation enzyme soluble glutathione S-transferase at non-toxic concentrations. Membrane bound glutathione S-transferase activity was significantly elevated in Roundup Ultra exposed worms, compared to treatment with equal glyphosate concentrations, but did not significantly differ from the control. Antioxidant enzyme superoxide dismutase was significantly increased by glyphosate but in particular by Roundup Ultra exposure indicating oxidative stress. The results show that the formulation Roundup Ultra is of more ecotoxicological relevance than the glyphosate itself. - Roundup Ultra is of more ecotoxicological relevance than the active ingredient, glyphosate, to Lumbriculus variegatus regarding accumulation potential and enzymatic responses

  14. The potential of TiO2 nanoparticles as carriers for cadmium uptake in Lumbriculus variegatus and Daphnia magna

    DEFF Research Database (Denmark)

    Hartmann, Nanna Isabella Bloch; Legros, Samuel; Von der Kammer, Frank

    2012-01-01

    variegatus, was investigated both in the absence and presence of titanium dioxide (TiO2) nanoparticles (P25 Evonic Degussa, d: 30nm). The uptake of cadmium in sub-lethal concentrations was also studied in the absence and presence of 2mg/L TiO2 nanoparticles. Formation of larger nanoparticles aggregates...

  15. Quantitative analysis of diet structure by real-time PCR, reveals different feeding patterns by two dominant grasshopper species

    Science.gov (United States)

    Huang, Xunbing; Wu, Huihui; McNeill, Mark Richard; Qin, Xinghu; Ma, Jingchuan; Tu, Xiongbing; Cao, Guangchun; Wang, Guangjun; Nong, Xiangqun; Zhang, Zehua

    2016-01-01

    Studies on grasshopper diets have historically employed a range of methodologies, each with certain advantages and disadvantages. For example, some methodologies are qualitative instead of quantitative. Others require long experimental periods or examine population-level effects, only. In this study, we used real-time PCR to examine diets of individual grasshoppers. The method has the advantage of being both fast and quantitative. Using two grasshopper species, Oedaleus asiaticus and Dasyhippus barbipes, we designed ITS primer sequences for their three main host plants, Stipa krylovii, Leymus chinensis and Cleistogenes squarrosa and used real-time PCR method to test diet structure both qualitatively and quantitatively. The lowest detection efficiency of the three grass species was ~80% with a strong correlation between actual and PCR-measured food intake. We found that Oedaleus asiaticus maintained an unchanged diet structure across grasslands with different grass communities. By comparison, Dasyhippus barbipes changed its diet structure. These results revealed why O. asiaticus distribution is mainly confined to Stipa-dominated grassland, and D. barbipes is more widely distributed across Inner Mongolia. Overall, real-time PCR was shown to be a useful tool for investigating grasshopper diets, which in turn offers some insight into grasshopper distributions and improved pest management. PMID:27562455

  16. Life-cycle toxicity of bis(tributyltin) oxide to the sheepshead minnow (Cyprinodon variegatus).

    Science.gov (United States)

    Manning, C S; Lytle, T F; Walker, W W; Lytle, J S

    1999-08-01

    The effects of tributyltin (TBT) to the life cycle of the estuarine fish Cyprinodon variegatus were examined in a 180-day flow-through exposure. The study was initiated with embryos less than 24 h postfertilization and monitored through hatch, maturation, growth, and reproduction under continuous exposure to mean measured TBT concentrations of 5.4, 3.2, 1.3, 0.66, and 0.41 microg TBT/L. Progeny isolated at the onset of reproduction by the parental generation (F0) were monitored for survival as embryos, survival as fry/juveniles, and growth 30 days postisolation. TBT, at a concentration of 5.4 microg/L, significantly reduced embryo survival of the F0 generation sheepshead minnows. By day 145 of the exposure, significant effects to the survival of this generation increased and included all test concentrations >/=0.66 microg/L. Survival of 0.66 microg/L was reduced 59% relative to control survival by termination of the F0 generation. Growth of F0 generation organisms as measured by standard length was significantly reduced only on day 90 at 3.2 microg/L, however no significant reductions of wet or dry weight related to treatment concentration were detected. Due to complete mortality of organisms exposed to 5.4 microg/L by study day 7, effects to fecundity and progeny were monitored at measured concentrations of 3.2, 1.3, 0.66, and 0.41 microg TBT/L. Fecundity, as measured by the production of viable eggs produced per female per day, was unaffected by any of the test treatments. All F1 generation embryos isolated from treatment chambers into 3.2 microg/L died. Survival, standard length, wet and dry weight of the F1 generation at the remaining treatment concentrations were unaffected. The results of this study indicate that exposure to TBT reduced survival of the F0 generation sheepshead minnow and establishes the lowest observed effect concentration (LOEC) as 0.66 microg TBT/L, and the no observed effect concentration (NOEC) as 0.41 microg TBT/L for this species

  17. Aspectos morfológicos da placenta da preguiça, Bradypus variegatus Shinz, 1825

    Directory of Open Access Journals (Sweden)

    Marleyne José Afonso Accyoli Lins Amorin

    2003-01-01

    Full Text Available Estudaram-se os aspectos morfológicos da placenta e das membranas fetais de 03 placentas de bichos-preguiça (Bradypus variegatus, adultas e prenhes, originárias da Zona da Mata do Estado de Pernambuco. Essas estruturas foram obtidas de 03 fêmeas doadas pela Universidade Federal de Pernambuco, das quais duas encontravam-se congeladas e a terceira foi colhida mediante realização de cirurgia cesariana, onde mãe e feto foram preservados. Depois de descongeladas, as placentas foram fixadas em solução aquosa de formol 10,00%. Da placenta obtida da cesariana colheram-se pequenos fragmentos da região placentária e do funículo umbilical, os quais foram fixados em paraformoldeido 4,00%, tampão fosfato pH 7,4. Os fragmentos passaram pela rotina histológica, onde foram coradas em Hematoxilina e Eosina e Tricrômio de Masson. A placenta da preguiça é corioamniótica, com o cório viloso constituindo os lobos placentários, que se localizam na região fúndica do útero, e o cório liso relacionando-se com a face interna do útero. Nas placentas de final de prenhez os lobos aglomeram-se e fundem-se aumentando de tamanho, formando uma massa principal discóide, caracterizando uma placenta zonária discoidal, que se une ao feto pelo funículo umbilical, constituído por duas artérias e uma veia umbilical. Os resultados histológicos demonstraram que a placenta desses animais é labiríntica e endoteliocorial. Assim, a placenta da preguiça pode ser classificada como labiríntica, endoteliocorial, múltipla, discóide (a termo e corioamniótica.

  18. Grazing damage to plants and gastropod and grasshopper densities in a CO 2-enrichment experiment on calcareous grassland

    Science.gov (United States)

    Ledergerber, Stephan; Thommen, G. Heinrich; Baur, Bruno

    Plant-herbivore interactions may change as atmospheric CO 2 concentrations continue to rise. We examined the effects of elevated atmospheric CO 2 and CO 2-exposure chambers on the grazing damage to plants, and on the abundances of potential herbivores (terrestrial gastropods and grasshoppers) in a calcareous grassland in the Jura mountains of Switzerland (village of Nenzlingen). Individuals of most plant species examined showed slight grazing damage. However, plots with CO 2 enrichment and plots with ambient atmosphere did not differ in the extent of grazing damage. Similarly, plots with CO 2 enrichment and plots with ambient atmosphere did not differ in either gastropod or grasshopper density. Experimental plots with and without chambers did not differ in the number of gastropods. However, the densities of gastropods and grasshoppers and extent of grazing damage to plants were generally lower in the experimental area than in the grassland outside the experimental field.

  19. Control of grasshoppers by combined application of Paranosema locustae and an insect growth regulator (IGR) (cascade) in rangelands in China.

    Science.gov (United States)

    Guo, Yanyan; An, Zhao; Shi, Wangpeng

    2012-12-01

    The relatively low direct mortality caused by Paranosema locustae (Canning) has limited its application for controlling grasshopper when densities are high, and this study sought to determine if the simultaneous use of this pathogen and the IGR, Flufenoxuron (Cascade) could provide effective control. Nine treatments were tested: 45% Malathion EC at 1500 ml/ha, 5% Cascade at 150 ml/ha, 5% Cascade at 75 ml/ha, 5% Cascade at 37.5 ml/ha, P. locustae at 7.5 x 10(9) spores/ha, combinations of 5% Cascade at 75 ml/ha and P. locustae at 7.5 x 10(9) spores/ha, applied in different rations (1:1, 1:2, 1:3) in the same plot, the untreated control. P. locustae was applied on nonoverlapping plots with the IGR. The different in-plot combinations of P. locustae and Cascade in different ratios provided significantly better overall control of grasshoppers (all species) than the treatment of 5% Cascade of 150 ml/ha after 5d, but combinations were not significantly different from the other concentrations of Cascade after 12 and 31 d. When results were examined separately for specific species of grasshoppers, reduction of Dasyhippus harbipes (Fischer-Waldheim), was higher than that of Myrmeleotettix palpalis (Zubovsky). While combinations showed significant differences in the infection of different grasshopper species at 5 and 12 d posttreatment, no significant differences in rate of infection among the primary species (M. palpalis, D. harbipes, and Oedaleus asiaticus Bei-Bienko) were detected 31 d posttreatment. Our study found that P. locustae by itself could control grasshopper populations at medium densities but the combined application of P. locustae and Cascade at a ratio of 1:2 was more effective against high-density grasshopper populations.

  20. Vitellogenin-RNAi and ovariectomy each increase lifespan, increase protein storage, and decrease feeding, but are not additive in grasshoppers.

    Science.gov (United States)

    Tetlak, Alicia G; Burnett, Jacob B; Hahn, Daniel A; Hatle, John D

    2015-12-01

    Reduced reproduction has been shown to increase lifespan in many animals, yet the mechanisms behind this trade-off are unclear. We addressed this question by combining two distinct, direct means of life-extension via reduced reproduction, to test whether they were additive. In the lubber grasshopper, Romalea microptera, ovariectomized (OVX) individuals had a ~20% increase in lifespan and a doubling of storage relative to controls (Sham operated). Similarly, young female grasshoppers treated with RNAi against vitellogenin (the precursor to egg yolk protein) had increased fat body mass and halted ovarian growth. In this study, we compared VgRNAi to two control groups that do not reduce reproduction, namely buffer injection (Buffer) and injection with RNAi against a hexameric storage protein (Hex90RNAi). Each injection treatment was tested with and without ovariectomy. Hence, we tested feeding, storage, and lifespans in six groups: OVX and Buffer, OVX and Hex90RNAi, OVX and VgRNAi, Sham and Buffer, Sham and Hex90RNAi, and Sham and VgRNAi. Ovariectomized grasshoppers and VgRNAi grasshoppers each had similar reductions in feeding (~40%), increases in protein storage in the hemolymph (150-300%), and extensions in lifespan (13-21%). Ovariectomized grasshoppers had higher vitellogenin protein levels than did VgRNAi grasshoppers. Last but not least, when ovariectomy and VgRNAi were applied together, there was no greater effect on feeding, protein storage, or longevity. Hence, feeding regulation, and protein storage in insects, may be conserved components of life-extension via reduced reproduction.

  1. Grasshopper (Orthoptera: Acrididae) community composition in the rangeland of the northern slopes of The Qilian Mountains in northwestern China.

    Science.gov (United States)

    Sun, T; Liu, Z Y; Qin, L P; Long, R J

    2015-01-01

    In order to describe grasshopper (Orthoptera: Acrididae) species composition, diversity, abundance, and density of four rangelands types, we compared the grasshopper community composition and dynamics in the rangeland of the northern slopes of the Qilian Mountains. In total, 55 grasshopper species were collected from 2007 to 2009, representing three families and six subfamilies. The subfamily Oedipodinae was dominant, followed by Gomphocerinae and Catantopinae. Species abundance varied among rangeland types (RTs). The greatest abundance of grasshoppers was found in mountain rangeland, while the lowest abundance of grasshoppers was caught in alpine shrublands. Three species (Chorthippus cf. brunneus (Thunberg) (Acrididae), Chorthippus Dubius (Zubovski), and Gomphocerus licenti (Chang) were broadly distributed in the four RTs and constituted 7.5% of all grasshoppers collected. Ch. dubius was very abundant in desert rangeland and alpine shrubland. Bryodema dolichoptera Yin et Feng Eremippus qilianshanensis Lian and Zheng, and Filchnerella qilianshanensis Xi and Zheng (Pamphagidae) were endemic to the region of the Qilian Mountains. Species similarity between RTs ranged from 17.8 to 51.6 based on the Renkonen index. Similarly, the Sörensen index indicated a wide separation in species composition among RTs. The abundance of the eight most common species showed obvious differences among RTs and years. On average, mountain rangeland had the highest density values in 2007 and 2008, and alpine shrubland supported the smallest density. The densities in desert and mountain rangeland in 2007 were significantly higher than in 2008, while alpine rangeland and shrublands did not present obvious differences among years. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

  2. Microsatellite Markers for the Chameleon Grasshopper (Kosciuscola tristis (Orthoptera: Acrididae, an Australian Alpine Specialist

    Directory of Open Access Journals (Sweden)

    Ange-Marie Risterucci

    2012-09-01

    Full Text Available A set of polymorphic loci was characterised using an enrichment library for the Australian alpine specialist, the chameleon grasshopper (Kosciuscola tristis, an atypical grasshopper known for its remarkable temperature-controlled colour change. The number of alleles per locus ranged from three to 20 and observed heterozygosity from 0.16 to 0.76. These are the first microsatellite markers for a non-endangered Australian alpine animal and will inform questions of gene flow across the sky islands of this unique and threatened region.

  3. Change in the Chemical Profile of Mangifera indica Leaves after their Metabolism in the Tropidacris collaris Grasshopper.

    Science.gov (United States)

    da Silva, Rodolfo R; Moraes, Marcilio M; Camara, Claudio A G; Ramos, Clécio S

    2015-11-01

    This present work addresses research on the discovery of new compounds from natural sources. It is based on a study of Mangifera indica leaf metabolism by the Tropidacris collaris grasshopper. We found that the grasshopper hydrolyzed the flavonoid isoquercitrin to quercetin when the O-glycosidic bond was broken and sugar released as a probable energy source for the insect. There was not, however, hydrolysis of the major compound in the leaves, mangiferin, which contains the C-glycosidic bond. All compounds were isolated and their chemical structure determined by UV, IR, MS, 1H and 13C NMR.

  4. Age structure and feeding of the neotropical grasshopper Cornops aquaticum (Bruner) (Orthoptera: Acrididae) on water hyacinth.

    Science.gov (United States)

    Franceschini, M C; de Wysiecki, M L; Poi, A

    2013-08-01

    We aimed to evaluate the variation in the age structure of Cornops aquaticum (Bruner) population and its relation to the host plant biomass and the feeding of the different age classes of this grasshopper on the water hyacinth Eichhornia crassipes along 2 years, in a Paraná River floodplain lake (Chaco, Argentina). Individuals of C. aquaticum were captured with a 70-cm diameter sweep and separated in nymphs A (instars I and II), nymphs B (instars III to VI), adult females, and adult males; host plant biomass was sampled using a ring with a 0.30-m(2) diameter. Relative daily feeding of C. aquaticum population was calculated by multiplying the number of individuals captured per minute by the daily consumption by individual obtained in each age classes. We found that the age structure and the relative daily feeding of C. aquaticum varied between seasons and years. The highest values of grasshopper abundance, leaf biomass, and relative daily feeding of C. aquaticum population were observed in summer 2006. Plant biomass was directly correlated with nymph abundance and not correlated with adult abundance. Plant biomass available as refuge (leaves), food (laminas), and oviposition site (petioles) to C. aquaticum represented up to 62% of the total plant biomass. The results obtained in C. aquaticum show the importance of considering total plant biomass and plant biomass available for herbivores separately. Our study highlights the need to find an adequate method to estimate the density of C. aquaticum and other semiaquatic grasshoppers in the Paraná River floodplain involving different seasons, years, and water phases (rising and falling).

  5. Deep phylogeographic divergence and cytonuclear discordance in the grasshopper Oedaleus decorus.

    Science.gov (United States)

    Kindler, Eveline; Arlettaz, Raphaël; Heckel, Gerald

    2012-11-01

    The grasshopper Oedaleus decorus is a thermophilic insect with a large, mostly south-Palaearctic distribution range, stretching from the Mediterranean regions in Europe to Central-Asia and China. In this study, we analyzed the extent of phylogenetic divergence and the recent evolutionary history of the species based on 274 specimens from 26 localities across the distribution range in Europe. Phylogenetic relationships were determined using sequences of two mitochondrial loci (ctr, ND2) with neighbour-joining and Bayesian methods. Additionally, genetic differentiation was analyzed based on mitochondrial DNA and 11 microsatellite markers using F-statistics, model-free multivariate and model-based Bayesian clustering approaches. Phylogenetic analyses detected consistently two highly divergent, allopatrically distributed lineages within O. decorus. The divergence among these Western and Eastern lineages meeting in the region of the Alps was similar to the divergence of each lineage to the sister species O. asiaticus. Genetic differentiation for ctr was extremely high between Western and Eastern grasshopper populations (F(ct)=0.95). Microsatellite markers detected much lower but nevertheless very significant genetic structure among population samples. The nuclear data also demonstrated a case of cytonuclear discordance because the affiliation with mitochondrial lineages was incongruent in Northern Italy. Taken together these results provide evidence of an ancient separation within Oedaleus and either historical introgression of mtDNA among lineages and/or ongoing sex-specific gene flow in this grasshopper. Our study stresses the importance of multilocus approaches for unravelling the history and status of taxa of uncertain evolutionary divergence. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Evaluation of a reproductive index to estimate grasshopper sparrow and eastern meadowlark reproductive success

    Science.gov (United States)

    Althoff, Donald P.; Gipson, P.S.; Pontius, J.S.; Japuntich, R.D.

    2009-01-01

    We compared an index of reproductive success based on breeding behavior to actual nest fates of grasshopper sparrows (Ammodramus savannarum) and eastern meadowlarks (Sturnella magna) on 12 plots (4-ha). Concordance of results between the two methods was 58% for grasshopper sparrows and 42% for eastern meadowlarks on a plot-by-plot basis. The indirect method yielded higher estimates of reproductive activity than nest monitoring for the balance of the plots,. There was little evidence that brown-headed cowbird (Molothrus ater) parasitism influenced the estimates of reproductive success using the indirect method. We concluded that nests and about-to-fledge nestlings were missed during searches on some plots. It may be appropriate to use an indirect method to more efficiently survey territories and/or plots for species with hard-to-find nests or when monitoring large areas. Use of a reproductive index may be appropriate and more time-efficient than nest searching and monitoring for comparing management effects such as burning, grazing, haying, military training, and other localized disturbances that are likely to affect reproductive success of grasshopper sparrows and eastern meadowlarks. However, nest monitoring may be necessary for more precise estimates of productivity necessary for long-term monitoring. Nest monitoring results are also likely to allow for direct comparisons to results from other studies because the index method requires intimate knowledge of the species being evaluated - a factor that could lead to reduced precision because the experience level of technicians relying only on behavioral cues from study-to-study is likely to vary considerably.

  7. A hierarchy of factors influence discontinuous gas exchange in the grasshopper Paracinema tricolor (Orthoptera: Acrididae).

    Science.gov (United States)

    Groenewald, Berlizé; Chown, Steven L; Terblanche, John S

    2014-10-01

    The evolutionary origin and maintenance of discontinuous gas exchange (DGE) in tracheate arthropods are poorly understood and highly controversial. We investigated prioritization of abiotic factors in the gas exchange control cascade by examining oxygen, water and haemolymph pH regulation in the grasshopper Paracinema tricolor. Using a full-factorial design, grasshoppers were acclimated to hypoxic or hyperoxic (5% O2, 40% O2) gas conditions, or dehydrated or hydrated, whereafter their CO2 release was measured under a range of O2 and relative humidity (RH) conditions (5%, 21%, 40% O2 and 5%, 60%, 90% RH). DGE was significantly less common in grasshoppers acclimated to dehydrating conditions compared with the other acclimations (hypoxia, 98%; hyperoxia, 100%; hydrated, 100%; dehydrated, 67%). Acclimation to dehydrating conditions resulted in a significant decrease in haemolymph pH from 7.0±0.3 to 6.6±0.1 (mean ± s.d., P=0.018) and also significantly increased the open (O)-phase duration under 5% O2 treatment conditions (5% O2, 44.1±29.3 min; 40% O2, 15.8±8.0 min; 5% RH, 17.8±1.3 min; 60% RH, 24.0±9.7 min; 90% RH, 20.6±8.9 min). The observed acidosis could potentially explain the extension of the O-phase under low RH conditions, when it would perhaps seem more useful to reduce the O-phase to lower respiratory water loss. The results confirm that DGE occurrence and modulation are affected by multiple abiotic factors. A hierarchical framework for abiotic factors influencing DGE is proposed in which the following stressors are prioritized in decreasing order of importance: oxygen supply, CO2 excretion and pH modulation, oxidative damage protection and water savings. © 2014. Published by The Company of Biologists Ltd.

  8. Specificity Responses of Grasshoppers in Temperate Grasslands to Diel Asymmetric Warming

    Science.gov (United States)

    Wu, Tingjuan; Hao, Shuguang; Sun, Osbert Jianxin; Kang, Le

    2012-01-01

    Background Global warming is characterized by not only an increase in the daily mean temperature, but also a diel asymmetric pattern. However, most of the current studies on climate change have only concerned with the mean values of the warming trend. Although many studies have been conducted concerning the responses of insects to climate change, studies that address the issue of diel asymmetric warming under field conditions are not found in the literature. Methodology/Principal Findings We conducted a field climate manipulative experiment and investigated developmental and demographic responses to diel asymmetric warming in three grasshopper species (an early-season species Dasyhippus barbipes, a mid-season species Oedaleus asiaticus, and a late-season species Chorthippus fallax). It was found that warming generally advanced the development of eggs and nymphs, but had no apparent impacts on the hatching rate of eggs, the emergence rate of nymphs and the survival and fecundity of adults in all the three species. Nighttime warming was more effective in advancing egg development than the daytime warming. The emergence time of adults was differentially advanced by warming in the three species; it was advanced by 5.64 days in C. fallax, 3.55 days in O. asiaticus, and 1.96 days in D. barbipes. This phenological advancement was associated with increases in the effective GDDs accumulation. Conclusions/Significance Results in this study indicate that the responses of the three grasshopper species to warming are influenced by several factors, including species traits, developmental stage, and the thermal sensitivity of the species. Moreover, species with diapausing eggs are less responsive to changes in temperature regimes, suggesting that development of diapausing eggs is a protective mechanism in early-season grasshopper for avoiding the risk of pre-winter hatching. Our results highlight the need to consider the complex relationships between climate change and

  9. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus.

    Directory of Open Access Journals (Sweden)

    Bob Laarhoven

    Full Text Available An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv. The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water quality were studied. Agar gel addition ameliorated growth conditions by reducing food hydrolysis and altering sediment structure. Best results for combined reproduction and growth were obtained with 0.6% agar-gel (20 ml, 10 g. fine sand, 40 g. coarse sand, and 105 mg fish food (Tetramin. With agar gel, ingestion and growth is more the result of addition of food in its original quality. Final tests with secondary potato starch sludge and wheat bran demonstrated that this test is appropriate for the comparison of solid feedstuffs and suspended organic waste streams. This test method is expected to be suitable for organic waste studies using other sediment dwelling invertebrates.

  10. Performance tests of a 2-meter grasshopper monochromator at photon factory

    International Nuclear Information System (INIS)

    Yanagihara, Mihiro; Maezawa, Hideki; Sasaki, Taizo; Suzuki, Yoshio; Iguchi, Yasuo.

    1984-12-01

    A 2-meter grasshopper monochromator was installed and adjusted at BL-11A in Photon Factory, and performance tests were carried out. The usable photon energy range for the monochromator is 90 to 1000 eV for a 2400 grooves/mm grating, and the flux is 10 8 - 10 9 photons/sec for entrance and exit slit widths of 15 μm. A resolving power of about 2000 is realized at 250 eV for this slit width. (author)

  11. Does insecticide drift adversely affect grasshoppers (Orthoptera: Saltatoria) in field margins? A case study combining laboratory acute toxicity testing with field monitoring data.

    Science.gov (United States)

    Bundschuh, Rebecca; Schmitz, Juliane; Bundschuh, Mirco; Brühl, Carsten Albrecht

    2012-08-01

    The current terrestrial risk assessment of insecticides regarding nontarget arthropods considers exclusively beneficial organisms, whereas herbivorous insects, such as grasshoppers, are ignored. However, grasshoppers living in field margins or meadows adjacent to crops may potentially be exposed to insecticides due to contact with or ingestion of contaminated food. Therefore, the present study assessed effects of five active ingredients of insecticides (dimethoate, pirimicarb, imidacloprid, lambda-cyhalothrin, and deltamethrin) on the survival of Chorthippus sp. grasshopper nymphs by considering two routes of exposure (contact and oral). The experiments were accompanied by monitoring field margins that neighbored cereals, vineyards, and orchards. Grasslands were used as reference sites. The laboratory toxicity tests revealed a sensitivity of grasshoppers with regard to the insecticides tested in the present study similar to that of the standard test species used in arthropod risk assessments. In the field monitoring program, increasing grasshopper densities were detected with increasing field margin width next to cereals and vineyards, but densities remained low over the whole range of field margins from 0.5 to 20 m next to orchards. Grasshopper densities equivalent to those of grassland sites were only observed in field margins exceeding 9 m in width, except for field margins next to orchards. These results may indicate that current insecticide risk assessments are insufficiently protective for grasshoppers in field margins. Copyright © 2012 SETAC.

  12. An abundance of Epsilonproteobacteria revealed in the gut microbiome of the laboratory cultured sea urchin, Lytechinus variegatus

    Science.gov (United States)

    Hakim, Joseph A.; Koo, Hyunmin; Dennis, Lacey N.; Kumar, Ranjit; Ptacek, Travis; Morrow, Casey D.; Lefkowitz, Elliot J.; Powell, Mickie L.; Bej, Asim K.; Watts, Stephen A.

    2015-01-01

    In this study, we have examined the bacterial community composition of the laboratory cultured sea urchin Lytechinus variegatus gut microbiome and its culture environment using NextGen amplicon sequencing of the V4 segment of the 16S rRNA gene, and downstream bioinformatics tools. Overall, the gut and tank water was dominated by Proteobacteria, whereas the feed consisted of a co-occurrence of Proteobacteria and Firmicutes at a high abundance. The gut tissue represented Epsilonproteobacteria as dominant, with order Campylobacterales at the highest relative abundance (>95%). However, the pharynx tissue was dominated by class Alphaproteobacteria. The gut digesta and egested fecal pellets had a high abundance of class Gammaproteobacteria, from which Vibrio was found to be the primary genus, and Epsilonproteobacteria, with genus Arcobacter occurring at a moderate level. At the class level, the tank water was dominated by Gammaproteobacteria, and the feed by Alphaproteobacteria. Multi-Dimensional Scaling analysis showed that the microbial community of the gut tissue clustered together, as did the pharynx tissue to the feed. The gut digesta and egested fecal pellets showed a similarity relationship to the tank water. Further analysis of Campylobacterales at a lower taxonomic level using the oligotyping method revealed 37 unique types across the 10 samples, where Oligotype 1 was primarily represented in the gut tissue. BLAST analysis identified Oligotype 1 to be Arcobacter sp., Sulfuricurvum sp., and Arcobacter bivalviorum at an identity level >90%. This study showed that although distinct microbial communities are evident across multiple components of the sea urchin gut ecosystem, there is a noticeable correlation between the overall microbial communities of the gut with the sea urchin L. variegatus culture environment. PMID:26528245

  13. An abundance of Epsilonproteobacteria revealed in the gut microbiome of the laboratory cultured sea urchin, Lytechinus variegatus

    Directory of Open Access Journals (Sweden)

    Joseph Antoine Hakim

    2015-10-01

    Full Text Available In this study, we have examined the bacterial community composition in the laboratory cultured sea urchin Lytechinus variegatus gut microbiome and its culture environment using NextGen amplicon sequencing of the V4 segment of the 16S rRNA gene, and downstream bioinformatics tools. Overall, the gut and tank water was dominated by Proteobacteria, whereas the feed consisted of a co-occurrence of Proteobacteria and Firmicutes at a high abundance. The gut tissue represented Epsilonproteobacteria as dominant, with order Campylobacterales at the highest relative abundance (>95%. However, the pharynx tissue was dominated by class Alphaproteobacteria. The gut digesta and egested fecal pellets had a high abundance of class Gammaproteobacteria, from which Vibrio was found to be the primary genus, and Epsilonproteobacteria, with genus Arcobacter occurring at a moderate level. At the class level, the tank water was dominated by Gammaproteobacteria, and the feed by Alphaproteobacteria. Multi-Dimensional Scaling analysis showed that the microbial community of the gut tissue clustered together, as did the pharynx tissue to the feed. The gut digesta and egested fecal pellets showed a similar relationship to the tank water. Further analysis of Campylobacterales at a lower taxonomic level using the oligotyping method revealed 37 unique types across the ten samples, where Oligotype 1 was primarily represented in the gut tissue. BLAST analysis identified Oligotype 1 to be Arcobacter sp., Sulfuricurvum sp., and Arcobacter bivalviorum at an identity level >90%. This study showed that although distinct microbial communities were evident across multiple components of the sea urchin gut ecosystem, there is a noticeable correlation between the overall microbial communities of the gut with the sea urchin L. variegatus culture environment.

  14. Invertebrates of The H.J. Andrews Experimental Forest, Western Cascades, Oregon: III. The Orthoptera (Grasshoppers and Crickets).

    Science.gov (United States)

    David C. Lightfoot

    1986-01-01

    An inventory of Orthoptera (grasshoppers and crickets) at the H.J. Andrews Experimental Forest, near Blue River, Oregon, was conducted to determine the species present and ecological relationships. A key for identification and an annotated list are presented. From qualitative assessments of successional habitat relationships, generalized species associations of forest...

  15. MicroRNAs of the mesothorax in Qinlingacris elaeodes, an alpine grasshopper showing a wing polymorphism with unilateral wing form.

    Science.gov (United States)

    Li, R; Jiang, G F; Ren, Q P; Wang, Y T; Zhou, X M; Zhou, C F; Qin, D Z

    2016-04-01

    MicroRNAs (miRNAs) are now recognized as key post-transcriptional regulators in regulation of phenotypic diversity. Qinlingacris elaeodes is a species of the alpine grasshopper, which is endemic to China. Adult individuals have three wing forms: wingless, unilateral-winged and short-winged. This is an ideal species to investigate the phenotypic plasticity, development and evolution of insect wings because of its case of unilateral wing form in both the sexes. We sequenced a small RNA library prepared from mesothoraxes of the adult grasshoppers using the Illumina deep sequencing technology. Approximately 12,792,458 raw reads were generated, of which the 854,580 high-quality reads were used only for miRNA identification. In this study, we identified 49 conserved miRNAs belonging to 41 families and 69 species-specific miRNAs. Moreover, seven miRNA*s were detected both for conserved miRNAs and species-specific miRNAs, which were supported by hairpin forming precursors based on polymerase chain reaction. This is the first description of miRNAs in alpine grasshoppers. The results provide a useful resource for further studies on molecular regulation and evolution of miRNAs in grasshoppers. These findings not only enrich the miRNAs for insects but also lay the groundwork for the study of post-transcriptional regulation of wing forms.

  16. Plant DNA Detection from Grasshopper Guts: A Step-by-Step Protocol, from Tissue Preparation to Obtaining Plant DNA Sequences

    Directory of Open Access Journals (Sweden)

    Alina Avanesyan

    2014-02-01

    Full Text Available Premise of the study: A PCR-based method of identifying ingested plant DNA in gut contents of Melanoplus grasshoppers was developed. Although previous investigations have focused on a variety of insects, there are no protocols available for plant DNA detection developed for grasshoppers, agricultural pests that significantly influence plant community composition. Methods and Results: The developed protocol successfully used the noncoding region of the chloroplast trnL (UAA gene and was tested in several feeding experiments. Plant DNA was obtained at seven time points post-ingestion from whole guts and separate gut sections, and was detectable up to 12 h post-ingestion in nymphs and 22 h post-ingestion in adult grasshoppers. Conclusions: The proposed protocol is an effective, relatively quick, and low-cost method of detecting plant DNA from the grasshopper gut and its different sections. This has important applications, from exploring plant “movement” during food consumption, to detecting plant–insect interactions.

  17. A novel adipokinetic peptide from the corpus cardiacum of the primitive caeliferan pygmy grasshopper Tetrix subulata (Caelifera, Tetrigidae)

    Czech Academy of Sciences Publication Activity Database

    Gäde, G.; Šimek, Petr; Marco, H. G.

    2015-01-01

    Roč. 68, JUN 01 (2015), s. 43-49 ISSN 0196-9781 R&D Projects: GA ČR GA13-18509S Institutional support: RVO:60077344 Keywords : insects * pygmy grasshoppers * Tetrigidae Subject RIV: EH - Ecology, Behaviour Impact factor: 2.535, year: 2015 http://www.sciencedirect.com/science/article/pii/S0196978115000339

  18. Differentiations of chitin content and surface morphologies of chitins extracted from male and female grasshopper species.

    Directory of Open Access Journals (Sweden)

    Murat Kaya

    Full Text Available In this study, we used Fourier transform infrared spectroscopy (FT-IR, elemental analysis (EA, thermogravimetric analysis (TGA, X-ray diffractometry (XRD, and scanning electron microscopy (SEM to investigate chitin structure isolated from both sexes of four grasshopper species. FT-IR, EA, XRD, and TGA showed that the chitin was in the alpha form. With respect to gender, two main differences were observed. First, we observed that the quantity of chitin was greater in males than in females and the dry weight of chitin between species ranged from 4.71% to 11.84%. Second, using SEM, we observed that the male chitin surface structure contained 25-90 nm wide nanofibers and 90-250 nm nanopores, while no pores or nanofibers were observed in the chitin surface structure of the majority of females (nanofibers were observed only in M. desertus females. In contrast, the elemental analysis, thermal properties, and crystalline index values for chitin were similar in males and females. Also, we carried out enzymatic digestion of the isolated chitins using commercial chitinase from Streptomyces griseus. We observed that there were no big differences in digestion rate of the chitins from both sexes and commercial chitin. The digestion rates were for grasshoppers' chitins; 88.45-95.48% and for commercial chitin; 94.95%.

  19. High similarity in physicochemical properties of chitin and chitosan from nymphs and adults of a grasshopper.

    Science.gov (United States)

    Erdogan, Sevil; Kaya, Murat

    2016-08-01

    This is the first study to explain the differences in the physicochemical properties of chitin and chitosan obtained from the nymphs and adults of Dociostaurus maroccanus using the same method. Fourier transform infrared spectroscopy, thermogravimetric analysis and x-ray diffraction analysis results demonstrated that the chitins from both the adults and nymphs were in the α-form. The chitin contents of the adults (14%) and nymphs (12%) were of the same order of magnitude. The crystalline index values of chitins from the adult and nymph grasshoppers were 71% and 74%, respectively. Thermal stabilities of the chitins and chitosans from adult and nymph grasshoppers were close to each other. Both the adult (7.2kDa) and nymph (5.6kDa) chitosans had low molar masses. Environmental scanning electron microscopy revealed that the surface morphologies of both chitins consisted of nanofibers and nanopores together, and they were very similar to each other. Consequently, it was determined that the physicochemical properties of the chitins and chitosans from adults and nymphs of D. maroccanus were not very different, so it can be hypothesized that the development of the chitin structure in the nymph has almost been completed and the nymph chitin has the same characteristics as the adult. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Differentiations of chitin content and surface morphologies of chitins extracted from male and female grasshopper species.

    Science.gov (United States)

    Kaya, Murat; Lelešius, Evaldas; Nagrockaitė, Radvilė; Sargin, Idris; Arslan, Gulsin; Mol, Abbas; Baran, Talat; Can, Esra; Bitim, Betul

    2015-01-01

    In this study, we used Fourier transform infrared spectroscopy (FT-IR), elemental analysis (EA), thermogravimetric analysis (TGA), X-ray diffractometry (XRD), and scanning electron microscopy (SEM) to investigate chitin structure isolated from both sexes of four grasshopper species. FT-IR, EA, XRD, and TGA showed that the chitin was in the alpha form. With respect to gender, two main differences were observed. First, we observed that the quantity of chitin was greater in males than in females and the dry weight of chitin between species ranged from 4.71% to 11.84%. Second, using SEM, we observed that the male chitin surface structure contained 25-90 nm wide nanofibers and 90-250 nm nanopores, while no pores or nanofibers were observed in the chitin surface structure of the majority of females (nanofibers were observed only in M. desertus females). In contrast, the elemental analysis, thermal properties, and crystalline index values for chitin were similar in males and females. Also, we carried out enzymatic digestion of the isolated chitins using commercial chitinase from Streptomyces griseus. We observed that there were no big differences in digestion rate of the chitins from both sexes and commercial chitin. The digestion rates were for grasshoppers' chitins; 88.45-95.48% and for commercial chitin; 94.95%.

  1. Postfledging survival of Grasshopper Sparrows in grasslands managed with fire and grazing

    Science.gov (United States)

    Hovick, Torre J.; Miller, James R.; Koford, Rolf R.; Engle, David M.; Debinski, Diane M.

    2011-01-01

    More accurate estimates of survival after nestlings fledge are needed for population models to be parameterized and population dynamics to be understood during this vulnerable life stage. The period after fledging is the time when chicks learn to fly, forage, and hide from predators. We monitored postfledging survival, causespecific mortality, and movements of Grasshopper Sparrows (Ammodramus savannarum) in grassland managed with fire and grazing. In 2009, we attached radio transmitters to 50 nestlings from 50 different broods and modeled their survival in response to climatic, biological, and ecological variables. There was no effect of treatment on survival. The factor most influencing postfledging survival was age; no other variable was significant. The majority of chicks (74%) died within 3 days of radio-transmitter attachment. We attributed most mortality to mesopredators (48%) and exposure (28%). Fledglings' movements increased rapidly for the first 4 days after they left the nest and were relatively stable for the remaining 10 days we tracked them. On average, fledglings took flight for the first time 4 days after fledging and flew ≥10 m 9 days after fledging. Our data show that the Grasshopper Sparrow's survival rates may be less than most models relying on nest-success estimates predict, and we emphasize the importance of incorporating estimates of survival during the postfledging period in demographic models.

  2. Pioneer neurons of the antennal nervous system project to protocerebral pioneers in the grasshopper Schistocerca gregaria.

    Science.gov (United States)

    Boyan, George; Ehrhardt, Erica

    2015-11-01

    The twin nerve tracts of the antenna of the grasshopper Schistocerca gregaria are established early in embryogenesis by sibling pairs of pioneers which delaminate from the epithelium into the lumen at the antennal tip. These cells can be uniquely identified via their co-expression of the neuronal labels horseradish peroxidase and the lipocalin Lazarillo. The apical pioneers direct axons toward the antennal base where they encounter guidepost-like cells called base pioneers which transiently express the same molecular labels as the apical pioneers. To what extent the pioneer growth cones then progress into the brain neuropil proper, and what their targets there might be, has remained unclear. In this study, we show that the apical antennal pioneers project centrally beyond the antennal base first into the deutocerebral, and then into the protocerebral brain neuropils. In the protocerebrum, we identify their target circuitry as being identified Lazarillo-positive cells which themselves pioneer the primary axon scaffold of the brain. The apical and base antennal pioneers therefore form part of a molecularly contiguous pathway from the periphery to an identified central circuit of the embryonic grasshopper brain.

  3. Within-season variability of fighting behaviour in an Australian alpine grasshopper.

    Science.gov (United States)

    Muschett, Giselle; Umbers, Kate D L; Herberstein, Marie E

    2017-01-01

    Throughout the breeding season, changing environmental and biological conditions can lead to variation in the reproductive landscape of many species. In alpine environments temperature is a key driver of behaviour for small ectotherms such as insects, but variable biotic factors such as mate quality and availability can also influence behaviour. Kosicuscola tristis is a small semelparous grasshopper of the Australian alpine region. In a rare behaviour among grasshoppers, K. tristis males engage in vigorous fights over access to females, involving mandible displays, kicking, biting and grappling. In this study we describe the variation in fighting behaviour of K. tristis throughout the breeding season and test several hypotheses related to temperature, body size, mating behaviour, and female quality. We show that K. tristis males are more aggressive toward each other at the end of the breeding season than at the beginning. This increased aggression is associated with decreased daily average temperatures (from ~20°C to ~9°C), decreased mating activity, increased female fecundity, and an unexpected trend toward an increase in female-to-male aggression. These results suggest that K. tristis is likely under increased selective pressure to time key life cycle events with favourable biological and climatic conditions. The stochastic nature of alpine environments combined with a relatively short life span and breeding season, as well as limited mating opportunities toward the end of the season may have contributed to the evolution of this extraordinary mating system.

  4. Suppression of grasshopper sound production by nitric oxide-releasing neurons of the central complex

    Science.gov (United States)

    Weinrich, Anja; Kunst, Michael; Wirmer, Andrea; Holstein, Gay R.

    2008-01-01

    The central complex of acridid grasshoppers integrates sensory information pertinent to reproduction-related acoustic communication. Activation of nitric oxide (NO)/cyclic GMP-signaling by injection of NO donors into the central complex of restrained Chorthippus biguttulus females suppresses muscarine-stimulated sound production. In contrast, sound production is released by aminoguanidine (AG)-mediated inhibition of nitric oxide synthase (NOS) in the central body, suggesting a basal release of NO that suppresses singing in this situation. Using anti-citrulline immunocytochemistry to detect recent NO production, subtypes of columnar neurons with somata located in the pars intercerebralis and tangential neurons with somata in the ventro-median protocerebrum were distinctly labeled. Their arborizations in the central body upper division overlap with expression patterns for NOS and with the site of injection where NO donors suppress sound production. Systemic application of AG increases the responsiveness of unrestrained females to male calling songs. Identical treatment with the NOS inhibitor that increased male song-stimulated sound production in females induced a marked reduction of citrulline accumulation in central complex columnar and tangential neurons. We conclude that behavioral situations that are unfavorable for sound production (like being restrained) activate NOS-expressing central body neurons to release NO and elevate the behavioral threshold for sound production in female grasshoppers. PMID:18574586

  5. Ampliación de la distribución geográfica de Liolaemus variegatus Laurent 1984 (Iguania: Liolaemidae en Bolivia

    Directory of Open Access Journals (Sweden)

    Aguilar-Kirigin, Alvaro Juan

    2012-08-01

    Full Text Available La revisión rigurosa de especímenes del género Liolaemus, depositados en la Colección Boliviana de Fauna, permite ampliar la distribución de la especie endémica Liolaemus variegatus a más de 500 km al sur del país en el departamento de Tarija.

  6. Application of a unique test design to determine the chronic toxicity of boron to the aquatic worm Lumbriculus variegatus and fatmucket mussel Lampsilis siliquoidea.

    Science.gov (United States)

    Hall, Scott; Lockwood, Rick; Harrass, Michael C

    2014-01-01

    The chronic (21- and 28-day) toxicity of boron was determined for two freshwater benthic macroinvertebrates: the fatmucket mussel Lampsilis siliquoidea and the aquatic worm Lumbriculus variegatus. The rapid depletion of boric acid from spiked sediments in tests using flow-through overlying waters was addressed by constant addition of boric acid to overlying water at concentrations matching those of the targeted porewater exposures. This proved highly successful in maintaining constant whole-sediment and sediment porewater boron concentrations. Boron sublethal 25 % inhibition concentration values based on porewater concentrations were 25.9 mg B/L (L. variegatus) and 38.5 mg B/L (L. siliquoidea), indicating similar test organism sensitivity. Expressed as dry whole-sediment values, the respective L. variegatus and L. siliquoidea sublethal (growth) IC25 values for whole-sediment exposures were 235.5 mg B/kg sediment dry weight (dw) and 310.6 mg B/kg dw. The worm lethality-based end points indicated greater sensitivity than the sublethal end points, bringing into question the validity of a "lethality" end point for L. variegatus given its fragmentation mode of reproduction. For comparison, water-only mussel exposures were tested resulting in an IC25 value of 34.6 mg B/L, which was within 20 % of the porewater value. This suggests that the primary route of boron exposure was through the aqueous phase. The results of this study indicated that for test materials that are readily water soluble, standard sediment test designs may be unsuitable, but water-only exposures can provide toxicological data representative of sediment tests.

  7. Supercooling capacity and cold hardiness of band-winged grasshopper eggs (Orthoptera: Acrididae).

    Science.gov (United States)

    Pang, Bao-Ping; Li, Na; Zhou, Xiao-Rong

    2014-01-01

    The band-winged grasshopper, Oedaleus asiaticus Bei-Bienko, is one of the most dominant and economically important grasshopper species in the steppe grasslands and farming-pastoral ecotone in northern China. It is a univoltine species and overwinters as eggs in soil. The cold hardiness of its eggs was examined in the laboratory. Water content in soil significantly affected the supercooling points (SCPs), water content and fat content of prediapause eggs. With the increase of water content in soil, the SCP, and water content of prediapause eggs rose whereas the fat content declined. There was a significant relationship between the SCP and water content or fat content of prediapause eggs. The SCPs of prediapause and diapause eggs varied from -7.6 to -28.4°C and the SCPs of eggs 30 d after oviposition could be divided into two groups. The means of high SCP group (-11.0 to -11.9°C) were much higher than those of low SCP group (-21.8 to -21.9°C), and the majority belonged to the latter (90.48-93.33%). The SCPs of prediapause eggs and early-diapause eggs 30 d after oviposition were significantly higher than those of deep-diapause eggs 60 d after oviposition. The survival rates of diapause eggs were significantly different among different temperature treatments. The survival rate was higher than 88% at greater than -20°C and declined significantly to 57% at -25°C, and suddenly dropped to zero at -30°C. The lower lethal temperature (Ltemp50) for 12 h exposure was -25.3°C and the lower lethal time (Ltime50) at -20°C was 32.8 d. As the mean SCPs of diapause eggs were similar to their Ltemp50, the SCP of eggs can be considered as a good indicator of cold hardiness for O. asiaticus and that this grasshopper is a freeze-intolerant insect. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  8. Detection experiments with humans implicate visual predation as a driver of colour polymorphism dynamics in pygmy grasshoppers

    Science.gov (United States)

    2013-01-01

    Background Animal colour patterns offer good model systems for studies of biodiversity and evolution of local adaptations. An increasingly popular approach to study the role of selection for camouflage for evolutionary trajectories of animal colour patterns is to present images of prey on paper or computer screens to human ‘predators’. Yet, few attempts have been made to confirm that rates of detection by humans can predict patterns of selection and evolutionary modifications of prey colour patterns in nature. In this study, we first analyzed encounters between human ‘predators’ and images of natural black, grey and striped colour morphs of the polymorphic Tetrix subulata pygmy grasshoppers presented on background images of unburnt, intermediate or completely burnt natural habitats. Next, we compared detection rates with estimates of capture probabilities and survival of free-ranging grasshoppers, and with estimates of relative morph frequencies in natural populations. Results The proportion of grasshoppers that were detected and time to detection depended on both the colour pattern of the prey and on the type of visual background. Grasshoppers were detected more often and faster on unburnt backgrounds than on 50% and 100% burnt backgrounds. Striped prey were detected less often than grey or black prey on unburnt backgrounds; grey prey were detected more often than black or striped prey on 50% burnt backgrounds; and black prey were detected less often than grey prey on 100% burnt backgrounds. Rates of detection mirrored previously reported rates of capture by humans of free-ranging grasshoppers, as well as morph specific survival in the wild. Rates of detection were also correlated with frequencies of striped, black and grey morphs in samples of T. subulata from natural populations that occupied the three habitat types used for the detection experiment. Conclusions Our findings demonstrate that crypsis is background-dependent, and implicate visual predation

  9. Cross-fostering alters advertisement vocalizations of grasshopper mice (Onychomys): Evidence for the developmental stress hypothesis.

    Science.gov (United States)

    Pasch, Bret; Abbasi, Mustafa Z; Wilson, Macey; Zhao, Daniel; Searle, Jeremy B; Webster, Michael S; Rice, Aaron N

    2016-04-01

    Nutritional stress can have lasting impacts on the development of traits involved in vocal production. Cross-fostering experiments are often used to examine the propensity for vocal learning in a variety of taxa, but few studies assess the influence of malnourishment that can occur as a byproduct of this technique. In this study, we reciprocally cross-fostered sister taxa of voluble grasshopper mice (genus Onychomys) to explore their propensity for vocal learning. Vocalizations of Onychomys leucogaster did not differ between control and cross-fostered animals, but cross-fostered Onychomys arenicola produced vocalizations that were higher in frequency in a direction away from tutors. These same animals exhibited a transient reduction in body mass early in development, indicative of malnutrition. Our findings simultaneously refute vocal learning and support the developmental stress hypothesis to highlight the importance of early ontogeny on the production of vocalizations later in life. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. The Ontology of Biological Groups: Do Grasshoppers Form Assemblages, Communities, Guilds, Populations, or Something Else?

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Lockwood

    2011-01-01

    Full Text Available Acridologists have used a variety of terms to describe groups of grasshoppers, including assemblage, community, guild, and population. This terminological diversity has raised the question of whether one of these descriptors is the correct one. I take the position that these terms pick out different features of the natural world such that there is no unconditionally or uniquely correct term. By adopting the framework of constrained perspectivism—a form of philosophical pragmatism—it is argued that a term is correct if it accurately reflects the conceptual framework of the investigator and effectively communicates this perspective to others. Such an approach gives rise to terminological pluralism that avoids the problems of relativism (the subjectivist's view that any term can be used and absolutism (the objectivist's view that there is a single correct term. I describe the contexts in which the most common terms are appropriate.

  11. Exposure to exogenous enkephalins disrupts reproductive development in the Eastern lubber grasshopper, Romalea microptera (Insecta: Orthoptera.

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar

    Full Text Available Enkephalins play a major role in reproductive physiology in crustaceans; however their role in reproductive development in insects is largely unknown. We investigated the effect of exposure to exogenous leucine-enkephalin (Leu-Enk, methionine-enkephalin (Met-Enk, and the opioid antagonist naloxone on gonad development in the Eastern lubber grasshopper, Romalea microptera. Injection of either Leu-Enk or naloxone alone significantly increased the testicular index and testicular follicular diameter in males, and the ovarian index, oocyte length, and oocyte diameter in females. In contrast, injection of Met-Enk inhibited all measures of reproductive development in both sexes. Surprisingly, co-injection of naloxone with either enkephalin enhanced the effect associated with administration of the enkephalin alone. This study clearly demonstrates the ability of enkephalins to disrupt insect sexual development and also suggests the existence of conserved enkephaline-dependent regulatory mechanisms in insects and crustaceans.

  12. Mark IV 'Grasshopper' grazing incidence mono-chromator for the Canadian Synchrotron Radiation Facility (CSRF)

    International Nuclear Information System (INIS)

    Tan, K.H.; Bancroft, G.M.; Coatsworth, L.L.; Yates, B.W.

    1982-01-01

    The vacuum, mechanical, and optical characteristics of a 'Grasshopper' grazing incidence monochromator for use with a synchrotron radiation source in the 30-300 eV range is described. The monochromator is compatible with ultrahigh vacuum ( -10 Torr throughout), and the motor driven scan mechanism is linear and reliable. The monchromator has been calibrated using several known absorption edges between 36 and 102 eV and a nonlinear least squares fit to the scan equation. These same absorption edges, plus a scan over zero order, show that the present resolution of the monochromator (with 10 and 16 μm exit and entrance slits respectively) is 0.16 A (0.06 eV at the AlLsub(2,3) edge). With 10 μm entrance and exit slits the resolution will be very close to the theoretical Δlambda = 0.083 A

  13. Complete mitochondrial genome of the geophilous grasshopper Trilophidia annulata (Acrididae: Oedipodinae: Trilophidia).

    Science.gov (United States)

    Guan, De-Long; Xu, Sheng-Quan

    2016-09-01

    The complete mitogenome of the geophilous grasshopper Trilophidia annulata was reconstructed from whole-genome Illumina sequencing data. After annotation, the circular genome was obtained with 16,501 bp in length, and typically consisted of 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. All PCGs were initiated with ATN codons, except ND2 with the start codon GTG. Most of the PCGs used TAA as their stop codons, while the others used TAG as stop codons (COX1, COX3&ND1). The nucleotide composition was asymmetric (42.3% A, 15.0% C, 11.0% G, 31.8% T) with an overall GC content of 25.9%. These data would contribute to the design of novel molecular markers for population and evolutionary research of T. annulata.

  14. Gender identification of Grasshopper Sparrows comparing behavioral, morphological, and molecular techniques

    Science.gov (United States)

    Ammer, F.K.; Wood, P.B.; McPherson, R.J.

    2008-01-01

    Correct gender identification in monomorphic species is often difficult especially if males and females do not display obvious behavioral and breeding differences. We compared gender specific morphology and behavior with recently developed DNA techniques for gender identification in the monomorphic Grasshopper Sparrow (Ammodramus savannarum). Gender was ascertained with DNA in 213 individuals using the 2550F/2718R primer set and 3% agarose gel electrophoresis. Field observations using behavior and breeding characteristics to identify gender matched DNA analyses with 100% accuracy for adult males and females. Gender was identified with DNA for all captured juveniles that did not display gender specific traits or behaviors in the field. The molecular techniques used offered a high level of accuracy and may be useful in studies of dispersal mechanisms and winter assemblage composition in monomorphic species.

  15. Liver cancer induction by 241Am and thorotrast in deer mice and grasshopper mice

    International Nuclear Information System (INIS)

    Taylor, G.N.; Mays, C.W.; Lloyd, R.D.; Jones, C.W.; Rojas, J.; Wrenn, M.E.; Ayoroa, G.; Kaul, A.; Riedel, W.

    1986-01-01

    The carcinogenicity of 241 Am, relative to thorotrast, has been determined in two species of mice: the grasshopper mouse (Onychomys leucogaster) and the deer mouse (Peromyscus maniculatus). These species were used since both have high uptakes of Pu and Am and, unlike conventional mice and rats, both retain relatively high concentrations of plutonium and americium in their livers. The study indicated that the liver carcinogenicity of comparable rad doses of 241 Am or thorotrast is approximately equal. The toxicity ratio ( 241 Am/thorotrast) for liver cancer induction approximated 1.2 with a range of about 0.6 to 1.6. This suggested that nonradiation factors of thorotrast were not significant in liver tumor induction. (orig.)

  16. The closed spiracle phase of discontinuous gas exchange predicts diving duration in the grasshopper Paracinema tricolor.

    Science.gov (United States)

    Gudowska, Agnieszka; Boardman, Leigh; Terblanche, John S

    2016-08-15

    The discontinuous gas exchange (DGE) pattern of respiration shown by many arthropods includes periods of spiracle closure (C-phase) and is largely thought to serve as a physiological adaptation to restrict water loss in terrestrial environments. One major challenge to this hypothesis is to explain the presence of DGE in insects in moist environments. Here, we show a novel ecological correlate of the C-phase, namely, diving behaviour in mesic Paracinema tricolor grasshoppers. Notably, maximal dive duration is positively correlated with C-phase length, even after accounting for mass scaling and absolute metabolic rate. Here, we propose that an additional advantage of DGE may be conferred by allowing the tracheal system to act as a sealed underwater oxygen reservoir. Spiracle closure may facilitate underwater submersion, which, in turn, may contribute to predator avoidance, the survival of accidental immersion or periodic flooding and the exploitation of underwater resources. © 2016. Published by The Company of Biologists Ltd.

  17. Distribution, habitat and behavior of grasshopper sparrows, Ammodramus savannarum(Passeriformes: Emberizidae in northeastern Nicaragua

    Directory of Open Access Journals (Sweden)

    Nidia Arguedas-Negrini

    2001-06-01

    Full Text Available During March and April of 1996, I made field observations of the sedentary subspecies of grasshopper sparrow (Ammodramus savannarum cracens, in 600 points of the pine savannas of northeastern Nicaragua. Isolated individuals were found in the humid depressions, but breeding populations were located exclusively in areas that had suffered a recent fire. Territorial behavior varied in intensity apparently as a function of territory size: the most aggressive males were those trying to defend smaller territories in populations close to Miskito villages, where most of the fires occur. In contrast to what is happening in other parts of Central America, the Nicaraguan grasshopper sparrow may be indirectly protected from extinction by the Miskito’s traditional fire practices.En marzo y abril de 1996, llevé a cabo observaciones del semillero colicorto (Ammodramus savannarum cracens en las sabanas de pino del noreste de Nicaragua. Encontré individuos aislados en las depresiones más húmedas, pero las poblaciones en estado reproductivo ocupaban solamente áreas que hubieran sido quemadas recientemente. El comportamiento territorial de las aves parecía estar relacionado al tamaño del territorio: las aves más agresivas defendían territorios relativamente pequeños, cercanos a los poblados miskitos, que es adonde los fuegos se producen con mayor frequencia. Fue notable la ausencia de posibles depredadores en las áreas más abiertas de la savanna. Contrario a lo que sucede en otras partes de Centroamérica, la persistencia de esta ave en las savannas de pino de Nicaragua podría estar asegurada por las tradiciones miskitas en el uso del fuego.

  18. Phenotypic disparity in Iberian short-horned grasshoppers (Acrididae): the role of ecology and phylogeny.

    Science.gov (United States)

    García-Navas, Vicente; Noguerales, Víctor; Cordero, Pedro J; Ortego, Joaquín

    2017-05-04

    The combination of model-based comparative techniques, disparity analyses and ecomorphological correlations constitutes a powerful method to gain insight into the evolutionary mechanisms that shape morphological variation and speciation processes. In this study, we used a time-calibrated phylogeny of 70 Iberian species of short-horned grasshoppers (Acrididae) to test for patterns of morphological disparity in relation to their ecology and phylogenetic history. Specifically, we examined the role of substrate type and level of ecological specialization in driving different aspects of morphological evolution (locomotory traits, chemosensitive organs and cranial morphology) in this recent radiation. We found a bimodal distribution of locomotory attributes corresponding to the two main substrate type guilds (plant vs. ground); plant-perching species tend to exhibit larger wings and thicker femora than those that remain on the ground. This suggests that life form (i.e., substrate type) is an important driving force in the evolution of morphological traits in short-horned grasshoppers, irrespective of ancestry. Substrate type and ecological specialization had no significant influence on head shape, a trait that showed a strong phylogenetic conservatism. Finally, we also found a marginal significant association between the length of antennae and the level of ecological specialization, suggesting that the development of sensory organs may be favored in specialist species. Our results provide evidence that even in taxonomic groups showing limited morphological and ecological disparity, natural selection seems to play a more important role than genetic drift in driving the speciation process. Overall, this study suggests that morphostatic radiations should not necessarily be considered as "non-adaptive" and that the speciation process can bind both adaptive divergence mechanisms and neutral speciation processes related with allopatric and/or reproductive isolation.

  19. U1 snDNA clusters in grasshoppers: chromosomal dynamics and genomic organization

    Science.gov (United States)

    Anjos, A; Ruiz-Ruano, F J; Camacho, J P M; Loreto, V; Cabrero, J; de Souza, M J; Cabral-de-Mello, D C

    2015-01-01

    The spliceosome, constituted by a protein set associated with small nuclear RNA (snRNA), is responsible for mRNA maturation through intron removal. Among snRNA genes, U1 is generally a conserved repetitive sequence. To unveil the chromosomal/genomic dynamics of this multigene family in grasshoppers, we mapped U1 genes by fluorescence in situ hybridization in 70 species belonging to the families Proscopiidae, Pyrgomorphidae, Ommexechidae, Romaleidae and Acrididae. Evident clusters were observed in all species, indicating that, at least, some U1 repeats are tandemly arrayed. High conservation was observed in the first four families, with most species carrying a single U1 cluster, frequently located in the third or fourth longest autosome. By contrast, extensive variation was observed among Acrididae, from a single chromosome pair carrying U1 to all chromosome pairs carrying it, with occasional occurrence of two or more clusters in the same chromosome. DNA sequence analysis in Eyprepocnemis plorans (species carrying U1 clusters on seven different chromosome pairs) and Locusta migratoria (carrying U1 in a single chromosome pair) supported the coexistence of functional and pseudogenic lineages. One of these pseudogenic lineages was truncated in the same nucleotide position in both species, suggesting that it was present in a common ancestor to both species. At least in E. plorans, this U1 snDNA pseudogenic lineage was associated with 5S rDNA and short interspersed elements (SINE)-like mobile elements. Given that we conclude in grasshoppers that the U1 snDNA had evolved under the birth-and-death model and that its intragenomic spread might be related with mobile elements. PMID:25248465

  20. Vitellogenin RNAi halts ovarian growth and diverts reproductive proteins and lipids in young grasshoppers.

    Science.gov (United States)

    Tokar, Derek R; Veleta, Katherine A; Canzano, Joseph; Hahn, Daniel A; Hatle, John D

    2014-11-01

    Reduced reproduction extends lifespan of females in many animals. To test the effects of reproduction on storage of macronutrients, we block reproductive output in the lubber grasshopper by injecting RNAi against the precursor to egg-yolk protein, vitellogenin, in early adulthood. Controls were injected with either buffer or RNAi against the major storage protein in the hemolymph, hexamerin-90. Vitellogenin RNAi greatly reduced both levels of mRNA for vitellogenin and ovarian growth, in comparison to both controls. Fat body mass was increased upon vitellogenin RNAi, but concentrations of the three hexameric storage proteins from the hemolymph were not. Surprisingly, hemolymph vitellogenin levels were increased upon vitellogenin RNAi. Total reproductive protein (hemolymph vitellogenin plus ovarian vitellin) was unchanged by vitellogenin RNAi, as reproductive protein was diverted to the hemolymph. Similarly, the increased lipid storage upon vitellogenin RNAi was largely attributable to the reduction in lipid in the ovary, due to decreased ovarian growth. A BLAST search revealed that the 515 bp sequence of vitellogenin used for RNAi had three 11 bp regions identical to the vitellogenin receptor of the cockroach Leucophaea maderae. This suggests that our treatment, in addition to reducing levels of vitellogenin transcript, may have also blocked transport of vitellogenin from the hemolymph to the ovary. This would be consistent with halted ovarian growth simultaneous with high levels of vitellogenin in the hemolymph. Nonetheless, the accumulation of vitellogenin, instead of hexameric storage proteins, is inconsistent with a simple model of the trade-off between reproduction and storage. This was observed in young females; future studies will address whether investment of proteins may shift to the soma as individuals age. Overall, our results suggest that blockage of reproduction in young grasshoppers redirects lipids to storage and reproductive proteins to the hemolymph

  1. Characterization and analysis of a de novo transcriptome from the pygmy grasshopper Tetrix japonica.

    Science.gov (United States)

    Qiu, Zhongying; Liu, Fei; Lu, Huimeng; Huang, Yuan

    2017-05-01

    The pygmy grasshopper Tetrix japonica is a common insect distributed throughout the world, and it has the potential for use in studies of body colour polymorphism, genomics and the biology of Tetrigoidea (Insecta: Orthoptera). However, limited biological information is available for this insect. Here, we conducted a de novo transcriptome study of adult and larval T. japonica to provide a better understanding of its gene expression and develop genomic resources for future work. We sequenced and explored the characteristics of the de novo transcriptome of T. japonica using Illumina HiSeq 2000 platform. A total of 107 608 206 paired-end clean reads were assembled into 61 141 unigenes using the trinity software; the mean unigene size was 771 bp, and the N50 length was 1238 bp. A total of 29 225 unigenes were functionally annotated to the NCBI nonredundant protein sequences (Nr), NCBI nonredundant nucleotide sequences (Nt), a manually annotated and reviewed protein sequence database (Swiss-Prot), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. A large number of putative genes that are potentially involved in pigment pathways, juvenile hormone (JH) metabolism and signalling pathways were identified in the T. japonica transcriptome. Additionally, 165 769 and 156 796 putative single nucleotide polymorphisms occurred in the adult and larvae transcriptomes, respectively, and a total of 3162 simple sequence repeats were detected in this assembly. This comprehensive transcriptomic data for T. japonica will provide a usable resource for gene predictions, signalling pathway investigations and molecular marker development for this species and other pygmy grasshoppers. © 2016 John Wiley & Sons Ltd.

  2. Local climate determines intra- and interspecific variation in sexual size dimorphism in mountain grasshopper communities.

    Science.gov (United States)

    Laiolo, P; Illera, J C; Obeso, J R

    2013-10-01

    The climate is often evoked to explain broad-scale clines of body size, yet its involvement in the processes that generate size inequality in the two sexes (sexual size dimorphism) remains elusive. Here, we analyse climatic clines of sexual size dimorphism along a wide elevation gradient (i) among grasshopper species in a phylogenetically controlled scenario and (ii) within species differing in distribution and cold tolerance, to highlight patterns generated at different time scales, mainly evolutionary (among species or higher taxa) and ontogenetic or microevolutionary (within species). At the interspecific level, grasshoppers were slightly smaller and less dimorphic at high elevations. These clines were associated with gradients of precipitation and sun exposure, which are likely indicators of other factors that directly exert selective pressures, such as resource availability and conditions for effective thermoregulation. Within species, we found a positive effect of temperature and a negative effect of elevation on body size, especially on condition-dependent measures of body size (total body length rather than hind femur length) and in species inhabiting the highest elevations. In spite of a certain degree of species-specific variation, females tended to adjust their body size more often than males, suggesting that body size in females can evolve faster among species and can be more plastic or dependent on nutritional conditions within species living in adverse climates. Natural selection on female body size may therefore prevail over sexual selection on male body size in alpine environments, and abiotic factors may trigger consistent phenotypic patterns across taxonomic scales. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  3. Multielectrode recordings from auditory neurons in the brain of a small grasshopper.

    Science.gov (United States)

    Bhavsar, Mit Balvantray; Heinrich, Ralf; Stumpner, Andreas

    2015-12-30

    Grasshoppers have been used as a model system to study the neuronal basis of insect acoustic behavior. Auditory neurons have been described from intracellular recordings. The growing interest to study population activity of neurons has been satisfied so far with artificially combining data from different individuals. We for the first time used multielectrode recordings from a small grasshopper brain. We used three 12μm tungsten wires (combined in a multielectrode) to record from local brain neurons and from a population of auditory neurons entering the brain from the thorax. Spikes of the recorded units were separated by sorting algorithms and spike collision analysis. The tungsten wires enabled stable recordings with high signal to noise ratio. Due to the tight temporal coupling of auditory activity to the stimulus spike collisions were frequent and collision analysis retrieved 10-15% of additional spikes. Marking the electrode position was possible using a fluorescent dye or electrocoagulation with high current. Physiological identification of units described from intracellular recordings was hard to achieve. 12μm tungsten wires gave a better signal to noise ratio than 15μm copper wires previously used in recordings from bees' brains. Recording the population activity of auditory neurons in one individual prevents interindividual and trial-to-trial variability which otherwise reduce the validity of the analysis. Double intracellular recordings have quite low success rate and therefore are rarely achieved and their stability is much lower than that of multielectrode recordings which allows sampling of data for 30min or more. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Spatial genetic structure and mitochondrial DNA phylogeography of Argentinean populations of the grasshopper Dichroplus elongatus.

    Directory of Open Access Journals (Sweden)

    Natalia Rosetti

    Full Text Available Many grasshopper species are considered of agronomical importance because they cause damage to pastures and crops. Comprehension of pest population dynamics requires a clear understanding of the genetic diversity and spatial structure of populations. In this study we report on patterns of genetic variation in the South American grasshopper Dichroplus elongatus which is an agricultural pest of crops and forage grasses of great economic significance in Argentina. We use Direct Amplification of Minisatellite Regions (DAMD and partial sequences of the cytochrome oxydase 1 (COI mitochondrial gene to investigate intraspecific structure, demographic history and gene flow patterns in twenty Argentinean populations of this species belonging to different geographic and biogeographic regions. DAMD data suggest that, although genetic drift and migration occur within and between populations, measurable relatedness among neighbouring populations declines with distance and dispersal over distances greater than 200 km is not typical, whereas effective gene flow may occur for populations separated by less than 100 km. Landscape analysis was useful to detect genetic discontinuities associated with environmental heterogeneity reflecting the changing agroecosystem. The COI results indicate the existence of strong genetic differentiation between two groups of populations located at both margins of the Paraná River which became separated during climate oscillations of the Middle Pleistocene, suggesting a significant restriction in effective dispersion mediated by females and large scale geographic differentiation. The number of migrants between populations estimated through mitochondrial and DAMD markers suggest that gene flow is low prompting a non-homogeneous spatial structure and justifying the variation through space. Moreover, the genetic analysis of both markers allows us to conclude that males appear to disperse more than females, reducing the chance of the

  5. Relevance of multiple spatial scales in habitat models: A case study with amphibians and grasshoppers

    Science.gov (United States)

    Altmoos, Michael; Henle, Klaus

    2010-11-01

    Habitat models for animal species are important tools in conservation planning. We assessed the need to consider several scales in a case study for three amphibian and two grasshopper species in the post-mining landscapes near Leipzig (Germany). The two species groups were selected because habitat analyses for grasshoppers are usually conducted on one scale only whereas amphibians are thought to depend on more than one spatial scale. First, we analysed how the preference to single habitat variables changed across nested scales. Most environmental variables were only significant for a habitat model on one or two scales, with the smallest scale being particularly important. On larger scales, other variables became significant, which cannot be recognized on lower scales. Similar preferences across scales occurred in only 13 out of 79 cases and in 3 out of 79 cases the preference and avoidance for the same variable were even reversed among scales. Second, we developed habitat models by using a logistic regression on every scale and for all combinations of scales and analysed how the quality of habitat models changed with the scales considered. To achieve a sufficient accuracy of the habitat models with a minimum number of variables, at least two scales were required for all species except for Bufo viridis, for which a single scale, the microscale, was sufficient. Only for the European tree frog ( Hyla arborea), at least three scales were required. The results indicate that the quality of habitat models increases with the number of surveyed variables and with the number of scales, but costs increase too. Searching for simplifications in multi-scaled habitat models, we suggest that 2 or 3 scales should be a suitable trade-off, when attempting to define a suitable microscale.

  6. Territory and nest site selection patterns by Grasshopper Sparrows in southeastern Arizona

    Science.gov (United States)

    Ruth, Janet M.; Skagen, Susan K.

    2017-01-01

    Grassland bird populations are showing some of the greatest rates of decline of any North American birds, prompting measures to protect and improve important habitat. We assessed how vegetation structure and composition, habitat features often targeted for management, affected territory and nest site selection by Grasshopper Sparrows (Ammodramus savannarum ammolegus) in southeastern Arizona. To identify features important to males establishing territories, we compared vegetation characteristics of known territories and random samples on 2 sites over 5 years. We examined habitat selection patterns of females by comparing characteristics of nest sites with territories over 3 years. Males selected territories in areas of sparser vegetation structure and more tall shrubs (>2 m) than random plots on the site with low shrub densities. Males did not select territories based on the proportion of exotic grasses. Females generally located nest sites in areas with lower small shrub (1–2 m tall) densities than territories overall when possible and preferentially selected native grasses for nest construction. Whether habitat selection was apparent depended upon the range of vegetation structure that was available. We identified an upper threshold above which grass structure seemed to be too high and dense for Grasshopper Sparrows. Our results suggest that some management that reduces vegetative structure may benefit this species in desert grasslands at the nest and territory scale. However, we did not assess initial male habitat selection at a broader landscape scale where their selection patterns may be different and could be influenced by vegetation density and structure outside the range of values sampled in this study.

  7. Prévalence et abondance de Charletonia cameroonensis Haitlinger ...

    African Journals Online (AJOL)

    SARAH

    31 août 2016 ... Kekeunou S, Weise S, Nolté C, Messi J, 2007b. Field feeding and reproductive activities of. Zonocerus variegatus (Linnaeus) (Orthoptera : Pyrgomorphidae) on selected legume for short fallow improvement in the southern Cameroon. Entomologia Generalis 3: 219-233. Kekeunou S, Weise S, Messi J, 2010.

  8. Interactions variations climatiques – insectes ravageurs et ...

    African Journals Online (AJOL)

    ... calamistis et de E. saccharina. De plus l'analyse de la perception des agriculteurs indique l'apparition de «nouveaux» ravageurs tels que les termites, le criquet puant Zonocerus variegatus et une recrudescence des ravageurs de stock. Mots clés: Changements climatiques, Sesamia calamistis, maïs, générations, termites.

  9. The nutritional value of fourteen species of edible insects in ...

    African Journals Online (AJOL)

    Seventeen species of edible insects representing nine families from south western Nigeria were analyzed for nutrient composition. They include the orders of Orthoptera, Lepidoptera, Coleoptera, Hymenoptera, and Isoptera. Analeptes trifasciata, Rhynchophorus phoenicis and Zonocerus variegatus has the highest crude ...

  10. Insectes ravageurs et champignons parasites associés au ...

    African Journals Online (AJOL)

    Ancistrotermes), stinking crickets (Zonocerus variegatus) and beetles Xyleborus aquilus). Isolation and identification revealed the presence of fungal species Phellinus noxius, Fusarium verticilioides and genius, Fusarium, Trichoderma, Penicillium and Aspergillus. Phellinus noxius, known like agent of brown root rot incite ...

  11. Sloths like it hot: ambient temperature modulates food intake in the brown-throated sloth (Bradypus variegatus

    Directory of Open Access Journals (Sweden)

    Rebecca N. Cliffe

    2015-04-01

    Full Text Available Sloths are considered to have one of the lowest mass-specific metabolic rates of any mammal and, in tandem with a slow digestive rate, have been theorized to have correspondingly low rates of ingestion. Here, we show in a study conducted over five months, that three captive Bradypus variegatus (Brown-throated sloths had a remarkably low mean food intake of 17 g kg−1day−1 (SD 4.2. Food consumption was significantly affected by ambient temperature, with increased intake at higher temperatures. We suggest that the known fluctuation of sloth core body temperature with ambient temperature affects the rate at which gut fauna process digesta, allowing for increased rates of fermentation at higher temperatures. Since Bradypus sloths maintain a constantly full stomach, faster rates of fermentation should enhance digestive throughput, increasing the capacity for higher levels of food intake, thereby allowing increased energy acquisition at higher ambient temperatures. This contrasts with other mammals, which tend to show increased levels of food intake in colder conditions, and points to the importance of temperature in regulating all aspects of energy use in sloths.

  12. Toxicological effects of irregularly shaped and spherical microplastics in a marine teleost, the sheepshead minnow (Cyprinodon variegatus).

    Science.gov (United States)

    Choi, Jin Soo; Jung, Youn-Joo; Hong, Nam-Hui; Hong, Sang Hee; Park, June-Woo

    2018-04-01

    The increasing global contamination of plastics in marine environments is raising public concerns about the potential hazards of microplastics to environmental and human health. Microplastics formed by the breakdown of larger plastics are typically irregular in shape. The objective of this study was to compare the effects of spherical or irregular shapes of microplastics on changes in organ distribution, swimming behaviors, gene expression, and enzyme activities in sheepshead minnow (Cyprinodon variegatus). Both types of microplastics accumulated in the digestive system, causing intestinal distention. However, when compared to spherical microplastics, irregular microplastics decreased swimming behavior (i.e., total distance travelled and maximum velocity) of sheepshead minnow. Both microplastics generated cellular reactive oxygen species (ROS), while ROS-related molecular changes (i.e., transcriptional and enzymatic characteristics) differed. This study provides toxicological insights into the impacts of environmentally relevant (fragmented) microplastics on fish and improves our understanding of the environmental effects of microplastics in the ecosystem. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Intraspecific variation in {sup 137}Cs activity concentration in sporocarps of Suillus variegatus in seven Swedish populations

    Energy Technology Data Exchange (ETDEWEB)

    Dahlberg, Anders [Swedish Univ. of Agricultural Sciences, Forest Mycology and Pathology Dept., Uppsala (Sweden); Nikolova, Ivanka; Johanson, K.-J. [Swedish Univ. of Agricultural Sciences, Radioecology Dept., Uppsala (Sweden)

    1997-05-01

    Following the Chernobyl accident in 1986, sporocarps of Suillus variegatus in Sweden showed a large amount of individual variation in concentration of {sup 137}Cs activity. Our aim was to determine the degrees to which this variability in sporocarp {sup 137}Cs levels could be explained by differences between (i) local populations, (ii) fungal genets and (iii) locations within genets. Five populations in a 100-yr-old Scots pine forest, located within a 1 km{sup 2} area, and two populations in Scots pine/Norway spruce forest, located 40 km north-west of Uppsala, were investigated. In total, 154 sporocarps were analysed to determine their {sup 137}Cs content. Of these, the genetic affiliations of 86 were successfully characterized using somatic incompatibility reactions. Twenty-six genets were found which, on average, consisted of 6.5 sporocarps. The genets averaged 7.5 m in size, measured as the length between the most distant sporocarps. The mean sporocarp {sup 137}Cs level was 67.1 {+-} 2.8 kBq kgsup(-1) D.W. (range between 13.6 and 182). According to analyses of variance, within-population variation accounted for 60% of the total variation in {sup 137}Cs levels, while 40% was ascribed to variation among populations. Within a population, {sup 137}Cs levels did not generally differ significantly between genets. Plausible reasons for intraspecific variation in radiocaesium content in sporocarps are discussed. (author).

  14. Sloths like it hot: ambient temperature modulates food intake in the brown-throated sloth (Bradypus variegatus).

    Science.gov (United States)

    Cliffe, Rebecca N; Haupt, Ryan J; Avey-Arroyo, Judy A; Wilson, Rory P

    2015-01-01

    Sloths are considered to have one of the lowest mass-specific metabolic rates of any mammal and, in tandem with a slow digestive rate, have been theorized to have correspondingly low rates of ingestion. Here, we show in a study conducted over five months, that three captive Bradypus variegatus (Brown-throated sloths) had a remarkably low mean food intake of 17 g kg(-1)day(-1) (SD 4.2). Food consumption was significantly affected by ambient temperature, with increased intake at higher temperatures. We suggest that the known fluctuation of sloth core body temperature with ambient temperature affects the rate at which gut fauna process digesta, allowing for increased rates of fermentation at higher temperatures. Since Bradypus sloths maintain a constantly full stomach, faster rates of fermentation should enhance digestive throughput, increasing the capacity for higher levels of food intake, thereby allowing increased energy acquisition at higher ambient temperatures. This contrasts with other mammals, which tend to show increased levels of food intake in colder conditions, and points to the importance of temperature in regulating all aspects of energy use in sloths.

  15. Studies of the effect of grasshopper abdominal secretion on wound healing with the use of murine model.

    Science.gov (United States)

    Buszewska-Forajta, M; Siluk, D; Daghir-Wojtkowiak, E; Sejda, A; Staśkowiak, D; Biernat, W; Kaliszan, R

    2015-12-24

    Grasshopper, belonging to Chorthippus sp., is a widespread insect inhabiting Polish territory. According to folk knowledge and folk tales, the grasshopper abdominal secretion was used by villagers of Central and South-West Poland as a natural drug accelerating the wound healing process. In the reported study the hypothesis about beneficial properties of grasshopper abdominal secretion on hard to heal wounds was verified. The study was carried out with the use of a murine model (mice C57BL/6). In order to verify the beneficial properties of grasshopper abdominal secretion, the wounds of 8mm in diameter were formed on one side of each tested mouse. The influence of ethanolic extract of insects' secretion on healing process was evaluated in comparison to ethanolic solution of allantoin and 30% aqueous solution of ethanol (medium). The observation was carried out over a 14 day period. Finally the statistical analysis (ANOVA) was carried out to highlight the differences in wound healing rate between applied preparations. Moreover, qualitative composition of grasshoppers' secretion was studied with the use of GC/MS technique. During the first three days of observation, wounds treated with allantoin were healed with higher efficiency in comparison to ethanol and insect secretion preparations. The trend of healing changed from the 4th day of observation. Wounds treated with grasshoppers' abdominal secretion were closuring faster than wounds treated with allantoin or ethanol. In this part of observation, in the case of allantoin and ethanol application, the wound healing efficiency was similar. Since the 9th day of experiment the measurement of wounds size was problematic, due to crust formation. Finally at the 14th day of the study, wounds were totally healed. Morphological study enabled to observe all the phases of healing. In the 5th and 8th day, the infiltration of neutrophils and mononuclear cells in dermis was observed, which is characteristic for inflammatory phase

  16. Independent Recruitment of a Flavin-Dependent Monooxygenase for Safe Accumulation of Sequestered Pyrrolizidine Alkaloids in Grasshoppers and Moths

    OpenAIRE

    Wang, Linzhu; Beuerle, Till; Timbilla, James; Ober, Dietrich

    2012-01-01

    Several insect lineages have developed diverse strategies to sequester toxic pyrrolizidine alkaloids from food-plants for their own defense. Here, we show that in two highly divergent insect taxa, the hemimetabolous grasshoppers and the holometabolous butterflies, an almost identical strategy evolved independently for safe accumulation of pyrrolizidine alkaloids. This strategy involves a pyrrolizidine alkaloid N-oxygenase that transfers the pyrrolizidine alkaloids to their respective N-oxide,...

  17. Factors associated with arrival densities of grasshopper sparrow (Ammodramus savannarum) and baird's sparrow (A. bairdii) in the upper great plains

    Science.gov (United States)

    Ahlering, M.A.; Johnson, D.H.; Faaborg, John

    2009-01-01

    Although critical to habitat and population management, the proximate cues that birds use to establish territories are largely unknown. Understanding these cues is important for birds, such as many grassland birds, that exhibit high annual variability in population density and make new habitat-selection decisions annually. Identifying the actual cues used is difficult in the field, but the factors associated with the arrival densities of birds can help uncover variables that are involved in or correlated with cues used for selection. During the summers of 2002–2004, we investigated how weather and local vegetation factors were related to arrival densities of Grasshopper Sparrows (Ammodramus savannarum) and Baird's Sparrows (A. bairdii) at three locations across North Dakota and Saskatchewan. Spring densities of Grasshopper Sparrows were positively correlated with concurrent May precipitation, whereas densities of Baird's Sparrows were negatively correlated with the previous winter's snowfall. We used a model-selection approach to evaluate the vegetation characteristics associated with arrival densities of birds. Grasshopper Sparrow densities showed a strong negative relationship to woody cover, and Baird's Sparrow densities showed a negative relationship to vegetation height and vegetation density near the ground. Our results provide a first detailed look at habitat and weather associations immediately after arrival in spring and an important first step in uncovering factors that may be involved in habitat selection in two grassland species.

  18. Natural Plant Essential Oils for Controlling the Grasshopper (Heteracris littoralis and their Pathological Effects on the Alimentary Canal

    Directory of Open Access Journals (Sweden)

    Aziza Sharaby

    2012-07-01

    Full Text Available In the present study, the toxic effect of three different natural essential oils of medicinal plants, namely Garlic (Allium sativum, Mint (Mintha pipereta and Eucalyptus (Eucalyptus globulus were tested on 1st nymphal instar of the grasshopper (Heteracris littoralis. The LC50 values of the tested oils were estimated after 14 days from feeding on treated diet mixed with different concentrations of the oil. The LC50 of the tested oils were arranged as follows: 0.067, 0.075 and 0.084ml. /100ml. diet for Garlic, Eucalyptus and Mint respectively. The effect of LC50 concentration of the oils on the biological aspects and histological changes that observed on the alimentary canal and fat bodies were recorded. The normal development of the grasshopper was exhibited. Results cleared that there was statistical variable numbers of increased the nymphal periods, life cycle, adults longevity and life span comparing with the control test. Garlic oil inhibited egg lying by the resulting females offspring of the treated1st instar nymphs. High reduction in the deposited eggs and egg fertility caused by Eucalyptus or Mint oil and marked malformation were observed. Histological changes on the alimentary canal and fat bodies of the remaining nymphs after treatment with Garlic oil (the most effective oil were detected by the light microscope have been recorded. The results suggest that the natural plant essential oils of Garlic, Eucalyptus and Mint may be used in IPM control program against H. littoralis grasshopper.

  19. The grasshopper

    DEFF Research Database (Denmark)

    Andersson, Olga; Hansen, Steen Honore; Hellman, Karin

    2013-01-01

    drug discovery phase, does not yet exist. A new refined ex vivo insect based BBB screening model that uses an intact, viable whole brain under controlled 'in vitro' like exposure conditions is presented. This model uses intact brains from dessert locusts, which are placed in a well containing...

  20. Correlations between potassium, rubidium and cesium (133Cs and 137Cs) in sporocarps of Suillus variegatus in a Swedish boreal forest

    International Nuclear Information System (INIS)

    Vinichuk, M.; Rosen, K.; Johanson, K.J.; Dahlberg, A.

    2011-01-01

    An analysis of sporocarps of ectomycorrhizal fungi Suillus variegatus assessed whether cesium ( 133 Cs and 137 Cs) uptake was correlated with potassium (K) or rubidium (Rb) uptake. The question was whether intraspecific correlations of Rb, K and 133 Cs mass concentrations with 137 Cs activity concentrations in sporocarps were higher within, rather than among, different fungal species, and if genotypic origin of sporocarps within a population affected uptake and correlation. Sporocarps (n = 51) from a Swedish forest population affected by the fallout after the Chernobyl accident were studied. The concentrations were 31.9 ± 6.79 g kg -1 for K (mean ± SD, dwt), 0.40 ± 0.09 g kg -1 for Rb, 8.7 ± 4.36 mg kg -1 for 133 Cs and 63.7 ± 24.2 kBq kg -1 for 137 Cs. The mass concentrations of 133 Cs correlated with 137 Cs activity concentrations (r = 0.61). There was correlation between both 133 Cs concentrations (r = 0.75) and 137 Cs activity concentrations (r = 0.44) and Rb, but the 137 Cs/ 133 Cs isotopic ratio negatively correlated with Rb concentration. Concentrations of K and Rb were weakly correlated (r = 0.51). The 133 Cs mass concentrations, 137 Cs activity concentrations and 137 Cs/ 133 Cs isotopic ratios did not correlate with K concentrations. No differences between, within or, among genotypes in S. variegatus were found. This suggested the relationships between K, Rb, 133 Cs and 137 Cs in sporocarps of S. variegatus is similar to other fungal species. - Highlights: → We studied uptake of Cs ( 133 Cs and 137 Cs), K and Rb by Suillus variegates sporocarps. → Genotypic origin of fungus did not affect uptake of studied elements (isotopes). → Genotypic origin did not affect correlation between Cs ( 133 Cs and 137 Cs), K and Rb.

  1. Bioaccumulation of perfluorinated carboxylates and sulfonates and polychlorinated biphenyls in laboratory-cultured Hexagenia spp., Lumbriculus variegatus and Pimephales promelas from field-collected sediments

    Energy Technology Data Exchange (ETDEWEB)

    Prosser, R.S., E-mail: prosserr@uoguelph.ca [School of Environmental Sciences, University of Guelph, Guelph, Ontario (Canada); Mahon, K. [Aquatic Toxicology Unit, Ontario Ministry of the Environment and Climate Change, Toronto, Ontario (Canada); Sibley, P.K. [School of Environmental Sciences, University of Guelph, Guelph, Ontario (Canada); Poirier, D.; Watson-Leung, T. [Aquatic Toxicology Unit, Ontario Ministry of the Environment and Climate Change, Toronto, Ontario (Canada)

    2016-02-01

    Polychlorinated biphenyls (PCBs) and perfluorinated carboxylates and sulfonates (PFASs) are persistent pollutants in sediment that can potentially bioaccumulate in aquatic organisms. The current study investigates variation in the accumulation of PCBs and PFASs in laboratory-cultured Hexagenia spp., Lumbriculus variegatus and Pimephales promelas from contaminated field-collected sediment using 28-day tests. BSAF{sup lipid} (lipid-normalized biota-sediment accumulation factor) values for total concentration of PCBs were greater in Hexagenia spp. relative to L. variegatus and P. promelas. The distribution of congeners contributing to the total concentration of PCBs in tissue varied among the three species. Trichlorobiphenyl congeners composed the greatest proportion of the total concentration of PCBs in L. variegatus while tetra- and pentabiphenyl congeners dominated in Hexagenia spp. and P. promelas. Perfluorooctane sulfonate (PFOS) was present in all three species at concentrations greater than all other PFASs analyzed. Hexagenia spp. also produced the greatest BSAF{sup lipid} and BSAF{sup ww} (non-lipid-normalized biota-sediment accumulation factor) values for PFOS relative to the other two species. However, this was not the case for all PFASs. The trend of BSAF values and number of carbon atoms in the perfluoroalkyl chain of perfluorinated carboxylates varied among the three species but was similar for perfluorinated sulfonates. Differences in the dominant pathways of exposure (e.g., water, sediment ingestion) likely explain a large proportion of the variation in accumulation observed across the three species. - Highlights: • BSAF values for total PCBs and PFOS greatest in Hexagenia spp. • BSAF values for other PFASs not consistently greatest in Hexagenia spp. • Trends in BSAF values for PFASs varied as a function of carbon chain length among species. • Differences in exposure pathways likely explain variation in accumulation across species.

  2. Variabilidad espacial y temporal de la abundancia del erizo de mar Lytechinus variegatus (Lamarck, 1816) en el Golfo de Batabanó, Cuba

    OpenAIRE

    Capetillo, N.; Lopeztegui, A.; Betanzos, A.; Hernández, R.

    2011-01-01

    Dada la importancia ecológica que tiene el erizo de mar Lytechinus variegatus y por formar parte de la dieta natural de muchos organismos marinos, entre los cuales se encuentran algunas especies de gran interés comercial, se realizó un estudio para describir las variaciones espaciales y temporales de la abundancia de sus poblaciones en el Golfo de Batabanó. La región fue dividida en dos sectores de estudio: Este (E) y Oeste (W) y se ubicaron 13 estaciones en las que se midió la sa...

  3. Are color or high rearing density related to migratory polyphenism in the band-winged grasshopper, Oedaleus asiaticus?

    Science.gov (United States)

    Cease, Arianne J; Hao, Shuguang; Kang, Le; Elser, James J; Harrison, Jon F

    2010-08-01

    Locusts represent an impressive example of migratory polyphenism, with high densities triggering a switch from a solitarious, shorter dispersal range, and sometimes greenish phenotype to a gregarious and sometimes darker form exhibiting behavioral, morphological and physiological traits associated with long-distance migratory swarms. While such polyphenism has been well documented in Locusta migratoria and Schistocerca gregaria, the extent to which other grasshoppers exhibit this type of migratory polyphenism is unclear. Anecdotally, the Chinese grasshopper, Oedaleus asiaticus, forms migratory swarms comprised mostly of a darker, brown-colored morph, but also exhibits a non-migratory green-colored morph that predominates at low densities. In a population in Inner Mongolia not currently exhibiting migratory swarms, we found that while green and brown O. asiaticus are found concurrently across our sampled range, only brown grasshoppers were found in high densities. Differences between field-collected brown and green forms matched some but not key predictions associated with the hypothesis that the brown form is morphologically and physiologically specialized for gregarious migration. Controlling for body mass, brown forms had more massive thoraxes, abdomens and legs, and higher metabolic rates, but not more flight muscle or lipid stores. Further, the brown and green grasshoppers did not differ in gregarious behavior, and neither would fly in multiple lab and field trials. Lab or field-rearing at high densities for one-to-multiple juvenile instars caused grasshoppers to exhibit some morphological traits predicted to benefit migration (larger wings and a shift in relative mass from abdomen to thorax), but did not change color or induce flight behavior. One hypothesis to explain these data is that a migratory form of O. asiaticus is partially triggered by high field densities, but that existing ecological conditions blocked full expression of such traits (and outbreak

  4. Meat fatty acid and cholesterol level of free-range broilers fed on grasshoppers on alpine rangeland in the Tibetan Plateau.

    Science.gov (United States)

    Sun, Tao; Liu, Zhiyun; Qin, Liping; Long, Ruijun

    2012-08-30

    Meat safety and nutrition are major concerns of consumers. The development of distinctive poultry production methods based on locally available natural resources is important. Grasshoppers are rich in important nutrients and occur in dense concentrations in most rangelands of northern China. Foraging chickens could be used to suppress grasshopper infestations. However, knowledge of the fatty acid content of meat from free-range broilers reared on alpine rangeland is required. Rearing conditions and diet did not significantly (P > 0.05) affect concentrations of saturated fatty acid (SFA), arachidonic acid, docosahexaenoic acid or the ratio of total n-6 to total n-3 fatty acids. Breast muscle of chickens that had consumed grasshoppers contained significantly (P 0.05) higher than intensively reared birds. Compared with meat from intensively reared birds, meat from free-range broilers had less cholesterol and higher concentrations of total lipid and phospholipids. Chickens eating grasshoppers in rangeland produce superior quality meat and reduce the grasshopper populations that damage the pastures. This provides an economic system of enhanced poultry-meat production, which derives benefits from natural resources rather than artificial additives. Copyright © 2012 Society of Chemical Industry.

  5. Pesticide exposure on sloths (Bradypus variegatus and Choloepus hoffmanni) in an agricultural landscape of Northeastern Costa Rica.

    Science.gov (United States)

    Pinnock Branford, Margaret Verónica; de la Cruz, Elba; Solano, Karla; Ramírez, Oscar

    2014-01-01

    Between 2005 and 2008, wild Bradypus variegatus and Choloepus hoffmanni inhabiting an agricultural landscape and captive animals from a rescue center in Northeastern Costa Rica were studied to assess exposure to pesticides. A total of 54 animals were sampled: 42 wild sloths captured at an agricultural landscape and 12 captive animals from a rescue center. Pesticides' active ingredients were determined in three sample matrices: hair, aqueous mixture (paws' wash) and cotton gauze (mouth clean) based on multi-residue gas chromatography methods. Recoveries tests ranged from 73 to 146% and relative standard deviations were less than 20% throughout all the recovery tests. Active ingredients detected in sloths samples were ametryn, chlorothalonil, chlorpyrifos, diazinon, difenoconazole, ethoprophos and thiabendazole. These active ingredients were used in intensive agricultural production for bananas, pineapples and other crops. Blood plasma cholinesterase activity (PChE) was determined by the Ellman method modified for micro plates. Enzyme activity determination was normalized to protein content in the samples according to Bradford method. Wild sloth PChE activity was similar for both species while sloths in captivity showed differences between species. Enzyme activity was significantly lower for two-toed sloths. This study showed that sloths were exposed to pesticides that caused acute and chronic effect in mammals and can also be a threat to other wildlife species. There is a need to better understand the potential effects of exposure to pesticides in sloths and other wild mammal populations, especially those threatened or endangered. More studies in this field must be carried out on the wildlife fauna inhabiting the agricultural landscape and its surroundings.

  6. ESTRUCTURA POBLACIONAL Y ETOLOGÍA DE Bradypus variegatus EN FRAGMENTO DE BOSQUE SECO TROPICAL, CÓRDOBA - COLOMBIA

    Directory of Open Access Journals (Sweden)

    Jesús Ballesteros C, M.Sc

    2009-12-01

    Full Text Available Objetivo. Contribuir al conocimiento de la composición poblacional y etología del oso perezoso (Bradypus variegatus en la reserva natural viento solar, un fragmento de bosque seco tropical (bs-T del municipio de Moñitos, departamento de Córdoba. Materiales y métodos. Durante octubre 2004 a mayo 2005, se realizaron conteos directos con observación visual en el sendero principal de la reserva, haciendo transectos de un kilómetro de largo x 100 m de ancho. Se registró el número de animales observados, hábitos alimenticios, estructura poblacional según sexo mediante marcado natural. Se realizaron observaciones sobre comportamiento animal y actividades de desplazamiento diurno, con anotaciones sobre su ecología, y aspectos importantes para la conservación. Resultados. En enero del 2005 se registraron 70 individuos, con una composición de 31% machos, 53% hembras y 16% crías. Durante la época seca del año, (enero-abril la mayoría de la vegetación arbórea es caducifolia, disminuyendo en forma importante el follaje de los árboles, lo cual facilitó el conteo de la población. La vegetación de bs-T está dominada por Pseudobombax septenatum, cuyo follaje es muy apetecido por el oso perezoso. Conclusiones. Los datos indican que la composición poblacional del oso perezoso en la reserva natural viento solar, está conformada principalmente por individuos adultos, encontrándose una baja proporción de crías; lo que podría estar reflejando problemas de crecimiento poblacional por efecto de baja disponibilidad y baja calidad del hábitat.

  7. Development of a methodology for successful multigeneration life-cycle testing of the estuarine sheepshead minnow, Cyprinodon variegatus.

    Science.gov (United States)

    Cripe, G M; Hemmer, B L; Goodman, L R; Vennari, J C

    2009-04-01

    Evaluation of effects on fish reproduction and development during chemical exposures lasting for multiple generations is sometimes limited by variable reproductive responses and the time required for the exposure. Established testing methods and the short life cycle of the sheepshead minnow, Cyprinodon variegatus, make this species particularly suitable for use in identifying potential impacts of contaminants in estuarine and marine environments. This study describes the refinement of life-cycle exposure methods that increased the reliability of reproduction in sheepshead minnows and reduced the time to maturation for larvae and juvenile fishes. A test of three spawning chamber designs, three sex ratios, and two photoperiods identified conditions that reduced the coefficient of variation in egg production from >100% to as little as 32%. The most reliable results were produced with groups of three female and two male fishes (all of similar size) when they were placed in a rectangular chamber and acclimated for 12 days. A test water temperature of 26.5 +/- 2 degrees C and a 14L:10D photoperiod resulted in fish producing a mean of 74 embryos per female per day, with a coefficient of variation of 31.8%. Egg fertility exceeded 90%, with a hatch rate of 95% for normal embryos (>or=80% yolk) and a hatch rate of size (>or=2.7 cm standard length) was critical for spawning readiness. Adult fish were prepared for the spawning assessment by adding frozen brine shrimp to their diet. Results of these experiments provide methods that are of particular interest in assessment of endocrine-disrupting chemicals that are known to affect reproduction.

  8. Importance of dose metrics for lethal and sublethal sediment metal toxicity in the oligochaete worm Lumbriculus variegatus

    Energy Technology Data Exchange (ETDEWEB)

    Penttinen, O.P.; Kilpi-Koski, J.; Toivainen, K. [Helsinki Univ., Lahti (Finland). Dept. of Ecology end Environmental Sciences; Jokela, M. [Mikkeli Univ. of Applied Sciences, Mikkeli (Finland); Vaeisaenen, A. [Jyvaeskylae Univ. (Finland). Dept. of Chemistry

    2008-02-15

    Background, aims, and scope. There is an increasing demand for controlled toxicity tests to predict biological effects related to sediment metal contamination. In this context, questions of metal-specific factors, sensitivity of toxicity endpoints, and variability in exposure duration arise. In addition, the choice of the dose metrics for responses is equally important and is related to the applicability of the concept of critical body residue (CBR) in exposure assessments, as well as being the main focus of this study. Methods. Experiments were conducted to assess toxicity of Cd, Cr, Cu and Pb to the oligochaete worm Lumbriculus variegatus with the aim of determining CBRs for two response metrics. Mortality and feeding activity of worms exposed to sediment-spiked metals were used as end-points in connection with residue analyses from both the organisms and the surrounding media. Results. LC50 values were 0.3, 1.4, 5.2, and 6.7 mg/L (from 4.7 {mu}mol/L to 128.0 {mu}mol/L), and the order of toxicity, from most toxic to least toxic, was Cu > Cd > Pb>Cr. By relating toxicity to body residue, variability in toxicity among the metals decreased and the order of toxicity was altered. The highest lethal residue value was obtained for Cu (10.8 mmol/kg) and the lowest was obtained for Cd (2.3 mmol/kg). In the 10-d sublethal test, both time and metal exposure were an important source of variation in the feeding activity of worms. The significant treatment effects were observed from worms exposed to Cd or Pb, with the controls yielding the highest feeding rate. However, quantitative changes in the measured end-point did not correlate with the exposure concentrations or body residues, which remained an order of magnitude lower than in the acute exposures. (orig.)

  9. Contributions to the study of the macroscopy anatomy of Bradypus torquatus (Linnaeus, 1758 and Bradypus variegatus (Schinz, 1825 brain

    Directory of Open Access Journals (Sweden)

    Jussara Rocha Ferreira

    2005-12-01

    Full Text Available A grande preocupação na preservação da fauna sul americana tem levado pesquisadores a intensa produção de trabalhos. Este trabalho constitui parte deste esforço para entender as estruturas animais, em especial do gênero Bradypus, ordem Edentata, descrevendo a anatomia macroscópica do encéfalo de duas espécies, Torquatus e Variegatus, ambas ocorrendo na mata atlântica brasileira. Os animais foram a óbito naturalmente, congelados reserva da Matinha, e descongelados, injetados, dissecados e corados por de técnicas apropriadas. Vemos as formações do neocórtex num modelo mais primitivo para mamíferos, uma predominância de áreas e estruturas ligadas ao olfato e diversas diferenças, quando comparadas a outros mamíferos, em especial a primatas. Dentre estas, a ocorrência de apenas 2 colículos no tronco encefálico, hipófise discoidal, grande fórnice e bem desenvolvidos pedúnculos cerebrais. As circunvoluções são brandas e ocorrem lobos semelhantes aos demais mamíferos, com cerebelo não recoberto pelas projeções dos telencéfalos e com proporção de até 1/4 em relação ao todo.

  10. Sequential loading of cohesin subunits during the first meiotic prophase of grasshoppers.

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    Ana M Valdeolmillos

    2007-02-01

    Full Text Available The cohesin complexes play a key role in chromosome segregation during both mitosis and meiosis. They establish sister chromatid cohesion between duplicating DNA molecules during S-phase, but they also have an important role during postreplicative double-strand break repair in mitosis, as well as during recombination between homologous chromosomes in meiosis. An additional function in meiosis is related to the sister kinetochore cohesion, so they can be pulled by microtubules to the same pole at anaphase I. Data about the dynamics of cohesin subunits during meiosis are scarce; therefore, it is of great interest to characterize how the formation of the cohesin complexes is achieved in order to understand the roles of the different subunits within them. We have investigated the spatio-temporal distribution of three different cohesin subunits in prophase I grasshopper spermatocytes. We found that structural maintenance of chromosome protein 3 (SMC3 appears as early as preleptotene, and its localization resembles the location of the unsynapsed axial elements, whereas radiation-sensitive mutant 21 (RAD21 (sister chromatid cohesion protein 1, SCC1 and stromal antigen protein 1 (SA1 (sister chromatid cohesion protein 3, SCC3 are not visualized until zygotene, since they are located in the synapsed regions of the bivalents. During pachytene, the distribution of the three cohesin subunits is very similar and all appear along the trajectories of the lateral elements of the autosomal synaptonemal complexes. However, whereas SMC3 also appears over the single and unsynapsed X chromosome, RAD21 and SA1 do not. We conclude that the loading of SMC3 and the non-SMC subunits, RAD21 and SA1, occurs in different steps throughout prophase I grasshopper meiosis. These results strongly suggest the participation of SMC3 in the initial cohesin axis formation as early as preleptotene, thus contributing to sister chromatid cohesion, with a later association of both RAD21

  11. Synchrotron x-ray studies of the keel of the short-spined sea urchin lytechinus variegatus: absorption microtomography (microCT) and small beam diffraction mapping

    International Nuclear Information System (INIS)

    Stock, S.R.; Barss, J.; Dahl, T.; Veis, A.; Almer, J.D.; De Carlo, F.

    2003-01-01

    In sea urchin teeth, the keel plays an important structural role, and this paper reports results of microstructural characterization of the keel of Lytechinus variegatus using two noninvasive synchrotron x-ray techniques: x-ray absorption microtomography (microCT) and x-ray diffraction mapping. MicroCT with 14 keV x-rays mapped the spatial distribution of mineral at the 1.3 microm level in a millimeter-sized fragment of a mature portion of the keel. Two rows of low absorption channels (i.e., primary channels) slightly less than 10 microm in diameter were found running linearly from the flange to the base of the keel and parallel to its sides. The primary channels paralleled the oral edge of the keel, and the microCT slices revealed a planar secondary channel leading from each primary channel to the side of the keel. The primary and secondary channels were more or less coplanar and may correspond to the soft tissue between plates of the carinar process. Transmission x-ray diffraction with 80.8 keV x-rays and a 0.1 mm beam mapped the distribution of calcite crystal orientations and the composition Ca(1-x)Mg(x)CO(3) of the calcite. Unlike the variable Mg concentration and highly curved prisms found in the keel of Paracentrotus lividus, a constant Mg content (x = 0.13) and relatively little prism curvature was found in the keel of Lytechinus variegatus.

  12. Identification of lipid fraction constituents from grasshopper (Chorthippus spp.) abdominal secretion with potential activity in wound healing with the use of GC-MS/MS technique.

    Science.gov (United States)

    Buszewska-Forajta, Magdalena; Siluk, Danuta; Struck-Lewicka, Wiktoria; Raczak-Gutknecht, Joanna; Markuszewski, Michał J; Kaliszan, Roman

    2014-02-01

    In recent years biologically active compounds isolated from insects call special interest of drug researchers. According to some Polish etnopharmacological observations, secretion from the grasshopper's abdomen (Orthoptera family) is believed to speed up the process of wound healing. In the present work we focused on determination of main components of the lipid fraction of material from grasshopper abdomen using GC-MS/MS. Samples were qualitatively analyzed using gas chromatography coupled with mass spectrometry. Both liquid-liquid extraction and solid-phase extraction pretreatment methods were used to concentrate and fractionate the compounds from the insect. In the derivatized fractions ca. 350 compounds were identified, including substances of known biological activity. The potential agents affecting wound healing have been indicated. A set of compounds characteristic for all the studied Chorthippus spp., have been identified. Data analysis revealed different lipidomic profiles of grasshoppers depending on the insects origin and collection area. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Generation of complex motor patterns in american grasshopper via current-controlled thoracic electrical interfacing.

    Science.gov (United States)

    Giampalmo, Susan L; Absher, Benjamin F; Bourne, W Tucker; Steves, Lida E; Vodenski, Vassil V; O'Donnell, Peter M; Erickson, Jonathan C

    2011-01-01

    Micro-air vehicles (MAVs) have attracted attention for their potential application to military applications, environmental sensing, and search and rescue missions. While progress is being made toward fabrication of a completely human-engineered MAV, another promising approach seeks to interface to, and take control of, an insect's nervous system. Cyborg insects take advantage of their innate exquisite loco-motor, navigation, and sensing abilities. Recently, several groups have demonstrated the feasibility of radio-controlled flight in the hawkmoth and beetle via electrical neural interfaces. Here, we report a method for eliciting the "jump" response in the American grasshopper (S. Americana). We found that stimulating the metathoracic T3 ganglion with constant-current square wave pulses with amplitude 186 ± 40 μA and frequency 190 ± 13 Hz reproducibly evoked (≥95% success rate) the desired motor activity in N=3 test subjects. To the best of our knowledge, this is the first report of an insect cyborg with a synchronous neuromuscular system.

  14. Transition-transversion bias is not universal: a counter example from grasshopper pseudogenes.

    Directory of Open Access Journals (Sweden)

    Irene Keller

    2007-02-01

    Full Text Available Comparisons of the DNA sequences of metazoa show an excess of transitional over transversional substitutions. Part of this bias is due to the relatively high rate of mutation of methylated cytosines to thymine. Postmutation processes also introduce a bias, particularly selection for codon-usage bias in coding regions. It is generally assumed, however, that there is a universal bias in favour of transitions over transversions, possibly as a result of the underlying chemistry of mutation. Surprisingly, this underlying trend has been evaluated only in two types of metazoan, namely Drosophila and the Mammalia. Here, we investigate a third group, and find no such bias. We characterize the point substitution spectrum in Podisma pedestris, a grasshopper species with a very large genome. The accumulation of mutations was surveyed in two pseudogene families, nuclear mitochondrial and ribosomal DNA sequences. The cytosine-guanine (CpG dinucleotides exhibit the high transition frequencies expected of methylated sites. The transition rate at other cytosine residues is significantly lower. After accounting for this methylation effect, there is no significant difference between transition and transversion rates. These results contrast with reports from other taxa and lead us to reject the hypothesis of a universal transition/transversion bias. Instead we suggest fundamental interspecific differences in point substitution processes.

  15. Transcriptome Profiling and In Silico Analysis of the Antimicrobial Peptides of the Grasshopper Oxya chinensis sinuosa.

    Science.gov (United States)

    Kim, In-Woo; Markkandan, Kesavan; Lee, Joon Ha; Subramaniyam, Sathiyamoorthy; Yoo, Seungil; Park, Junhyung; Hwang, Jae Sam

    2016-11-28

    Antimicrobial peptides/proteins (AMPs) are present in all types of organisms, from microbes and plants to vertebrates and invertebrates such as insects. The grasshopper Oxya chinensis sinuosa is an insect species that is widely consumed around the world for its broad medicinal value. However, the lack of available genetic information for this species is an obstacle to understanding the full potential of its AMPs. Analysis of the O. chinensis sinuosa transcriptome and expression profile is essential for extending the available genetic information resources. In this study, we determined the whole-body transcriptome of O. chinensis sinuosa and analyzed the potential AMPs induced by bacterial immunization. A high-throughput RNA-Seq approach generated 94,348 contigs and 66,555 unigenes. Of these unigenes, 36,032 (54.14%) matched known proteins in the NCBI database in a BLAST search. Functional analysis demonstrated that 38,219 unigenes were clustered into 5,499 gene ontology terms. In addition, 26 cDNAs encoding novel AMPs were identified by an in silico approach using public databases. Our transcriptome dataset and AMP profile greatly improve our understanding of O. chinensis sinuosa genetics and provide a huge number of gene sequences for further study, including genes of known importance and genes of unknown function.

  16. Brain regions for sound processing and song release in a small grasshopper.

    Science.gov (United States)

    Balvantray Bhavsar, Mit; Stumpner, Andreas; Heinrich, Ralf

    2017-05-01

    We investigated brain regions - mostly neuropils - that process auditory information relevant for the initiation of response songs of female grasshoppers Chorthippus biguttulus during bidirectional intraspecific acoustic communication. Male-female acoustic duets in the species Ch. biguttulus require the perception of sounds, their recognition as a species- and gender-specific signal and the initiation of commands that activate thoracic pattern generating circuits to drive the sound-producing stridulatory movements of the hind legs. To study sensory-to-motor processing during acoustic communication we used multielectrodes that allowed simultaneous recordings of acoustically stimulated electrical activity from several ascending auditory interneurons or local brain neurons and subsequent electrical stimulation of the recording site. Auditory activity was detected in the lateral protocerebrum (where most of the described ascending auditory interneurons terminate), in the superior medial protocerebrum and in the central complex, that has previously been implicated in the control of sound production. Neural responses to behaviorally attractive sound stimuli showed no or only poor correlation with behavioral responses. Current injections into the lateral protocerebrum, the central complex and the deuto-/tritocerebrum (close to the cerebro-cervical fascicles), but not into the superior medial protocerebrum, elicited species-typical stridulation with high success rate. Latencies and numbers of phrases produced by electrical stimulation were different between these brain regions. Our results indicate three brain regions (likely neuropils) where auditory activity can be detected with two of these regions being potentially involved in song initiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Prevalence and Molecular Identification of Nematode and Dipteran Parasites in an Australian Alpine Grasshopper (Kosciuscola tristis)

    Science.gov (United States)

    Umbers, Kate D. L.; Byatt, Lachlan J.; Hill, Nichola J.; Bartolini, Remo J.; Hose, Grant C.; Herberstein, Marie E.; Power, Michelle L

    2015-01-01

    In alpine Australia, Orthoptera are abundant, dominant herbivores, important prey species, and hosts for parasites and parasitoids. Despite the central role of orthopterans in alpine ecosystems, the impact of parasites on orthopteran populations is under-explored. In this study we describe the relationship between parasite prevalence and host sex, body size and year of collection. We accessed an existing, preserved collection of 640 Kosciuscola tristis collected from across its range between 2007 and 2011. Upon dissection we collected juvenile parasites and used molecular tools to identify them to three families (Nematoda; Mermithidae, and Arthropoda: Diptera: Tachinidae and Sarcophagidae). The prevalence of nematodes ranged from 3.5% to 25.0% and dipterans from 2.4% to 20.0%. Contrary to predictions, we found no associations between parasite prevalence and grasshopper sex or size. Although there was an association between prevalence of both nematodes and dipterans with year of collection, this is likely driven by a small sample size in the first year. Our results provide a foundation for future studies into parasite prevalence within the alpine environment and the abiotic factors that might influence these associations. PMID:25919745

  18. B Chromosome Variants of the Grasshopper Xyleus discoideus angulatus Are Potentially Derived from Pericentromeric DNA.

    Science.gov (United States)

    Bernardino, Andrezza C S; Cabral-de-Mello, Diogo C; Machado, Carolina B; Palacios-Gimenez, Octavio M; Santos, Neide; Loreto, Vilma

    2017-01-01

    B chromosomes, extra elements present in the karyotypes of some eukaryote species, have been described in the grasshopper Xyleus discoideus angulatus. Although some studies have proposed an autosomal origin of the B chromosome in X. d. angulatus, little is known about its repetitive DNA composition and evolutionary dynamics. The aim of the present work was to shed light on the B chromosome evolution in X. d. angulatus by cytogenetic analysis of 27 populations from Pernambuco and Ceará states (Brazil). The frequency of B chromosomes in the different populations was determined, and chromosome measurements and fluorescence in situ hybridization (FISH) with C0t-DNA and telomeric and B chromosome sequences were performed in cells from B-carrying individuals. The results revealed variations in B chromosome prevalence among the populations and showed that some B chromosomes were smaller in certain populations. FISH produced similar patterns for the C0t-DNA probe in all hybridized individuals, whereas telomeric and B chromosome probes, obtained by microdissection, exhibited variations in their distribution. These results indicate the presence of 3 morphotypes of B chromosomes in X. d. angulatus, with variation in repetitive DNA composition during their evolution. In this species, B chromosomes have an intraspecific origin and probably arose from the pericentromeric region of A chromosomes. © 2017 S. Karger AG, Basel.

  19. Discordant patterns of genetic and phenotypic differentiation in five grasshopper species codistributed across a microreserve network.

    Science.gov (United States)

    Ortego, Joaquín; García-Navas, Vicente; Noguerales, Víctor; Cordero, Pedro J

    2015-12-01

    Conservation plans can be greatly improved when information on the evolutionary and demographic consequences of habitat fragmentation is available for several codistributed species. Here, we study spatial patterns of phenotypic and genetic variation among five grasshopper species that are codistributed across a network of microreserves but show remarkable differences in dispersal-related morphology (body size and wing length), degree of habitat specialization and extent of fragmentation of their respective habitats in the study region. In particular, we tested the hypothesis that species with preferences for highly fragmented microhabitats show stronger genetic and phenotypic structure than codistributed generalist taxa inhabiting a continuous matrix of suitable habitat. We also hypothesized a higher resemblance of spatial patterns of genetic and phenotypic variability among species that have experienced a higher degree of habitat fragmentation due to their more similar responses to the parallel large-scale destruction of their natural habitats. In partial agreement with our first hypothesis, we found that genetic structure, but not phenotypic differentiation, was higher in species linked to highly fragmented habitats. We did not find support for congruent patterns of phenotypic and genetic variability among any studied species, indicating that they show idiosyncratic evolutionary trajectories and distinctive demographic responses to habitat fragmentation across a common landscape. This suggests that conservation practices in networks of protected areas require detailed ecological and evolutionary information on target species to focus management efforts on those taxa that are more sensitive to the effects of habitat fragmentation. © 2015 John Wiley & Sons Ltd.

  20. Fates of identified pioneer cells in the developing antennal nervous system of the grasshopper Schistocerca gregaria.

    Science.gov (United States)

    Ehrhardt, Erica; Graf, Philip; Kleele, Tatjana; Liu, Yu; Boyan, George

    2016-01-01

    In the early embryonic grasshopper, two pairs of sibling cells near the apex of the antenna pioneer its dorsal and ventral nerve tracts to the brain. En route, the growth cones of these pioneers contact a so-called base pioneer associated with each tract and which acts as a guidepost cell. Both apical and basal pioneers express stereotypic molecular labels allowing them to be uniquely identified. Although their developmental origins are largely understood, the fates of the respective pioneers remain unclear. We therefore employed the established cell death markers acridine orange and TUNEL to determine whether the apical and basal pioneers undergo apoptosis during embryogenesis. Our data reveal that the apical pioneers maintain a consistent molecular profile from their birth up to mid-embryogenesis, at which point the initial antennal nerve tracts to the brain have been established. Shortly after this the apical pioneers undergo apoptosis. Death occurs at a developmental stage similar to that reported elsewhere for pioneers in a leg - an homologous appendage. Base pioneers, by contrast, progressively change their molecular profile and can no longer be unequivocally identified after mid-embryogenesis. At no stage up to then do they exhibit death labels. If they persist, the base pioneers must be assumed to adopt a new role in the developing antennal nervous system. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Complete mitochondrial genome of the Chinese endemic grasshopper Fruhstorferiola kulinga (Orthoptera: Acrididae: Podismini).

    Science.gov (United States)

    Yang, Rui; Guan, De-Long; Xu, Sheng-Quan

    2016-09-01

    The whole-genome Illumina sequence of the Chinese endemic grasshopper Fruhstorferiola kulinga mitogenome was constructed and reported in this study. In all, the circular genome was obtained with 15,655 bp in length and contains 75.4% A + T. It typically consists of 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. All PCGs are initiated with ATN codons. Most of the PCGs use TAA as their stop codons, while the others use TAG as stop codons (COX1 and ND1). The size of the large and small ribosomal RNA genes are 1314 bp and 851 bp. The A + T-rich region (777 bp) showed strong resemblance to the other known Orthoptera insects. Our data would contribute to confirm the close relationship and other evolutionary researches of the F. kulinga.

  2. Novel odorant-binding proteins and their expression patterns in grasshopper, Oedaleus asiaticus.

    Science.gov (United States)

    Zhang, Shuo; Pang, Baoping; Zhang, Long

    2015-05-01

    Insects use olfaction to detect exogenous odors and adapt to environments. In their olfaction systems, odorant-binding proteins (OBPs) are believed to be a key component. The unique OBP system of each species reflects the evolution of chemosensation of insects with habits. Here, we for the first time identified 15 OBPs, OasiOBP1-15, of a grasshopper, Oedaleus asiaticus, that lives in the grasslands of Northern China and is closely related to the locust, Locusta migratoria. OasiOBP9 and OasiOBP10 are specifically expressed in the antennae. Other OBPs are expressed in the antennae as well as other chemosensory organs, such as the mouthparts and wings. Significantly more OasiOBP7 was detected in male than female antennae, but there are 9 OBPs that were more expressed in female than male antennae by quantitative real-time PCR. Phylogenetic analysis indicated that most of the O. asiaticus OBPs are similar to those of L. migratoria, but some are substantially different. This indicates that the OBPs originally evolved in a common ancestor, but their unique chemosensory systems are adapted to different ecosystems. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Axogenesis in the antennal nervous system of the grasshopper Schistocerca gregaria revisited: the base pioneers.

    Science.gov (United States)

    Ehrhardt, Erica; Liu, Yu; Boyan, George

    2015-01-01

    The antennal nervous system of the grasshopper Schistocerca gregaria comprises two parallel pathways projecting to the brain, each pioneered early in embryogenesis by a pair of sibling cells located at the antennal tip. En route, the growth cones of pioneers from one pathway have been shown to contact a guidepost-like cell called the base pioneer. Its role in axon guidance remains unclear as do the cellular guidance cues regulating axogenesis in the other pathway supposedly without a base pioneer. Further, while the tip pioneers are known to delaminate from the antennal epithelium into the lumen, the origin of this base pioneer is unknown. Here, we use immunolabeling and immunoblocking methods to clarify these issues. Co-labeling against the neuron-specific marker horseradish peroxidase and the pioneer-specific cell surface glycoprotein Lazarillo identifies not only the tip pioneers but also a base pioneer associated with each of the developing antennal pathways. Both base pioneers co-express the mesodermal label Mes3, consistent with a lumenal origin, whereas the tip pioneers proved Mes3-negative confirming their affiliation with the ectodermal epithelium. Lazarillo antigen expression in the antennal pioneers followed a different temporal dynamic: continuous in the tip pioneers, but in the base pioneers, only at the time their filopodia and those of the tip pioneers first recognize one another. Immunoblocking of Lazarillo expression in cultured embryos disrupts this recognition resulting in misguided axogenesis in both antennal pathways.

  4. Montane and coastal species diversification in the economically important Mexican grasshopper genus Sphenarium (Orthoptera: Pyrgomorphidae).

    Science.gov (United States)

    Pedraza-Lara, Carlos; Barrientos-Lozano, Ludivina; Rocha-Sánchez, Aurora Y; Zaldívar-Riverón, Alejandro

    2015-03-01

    The genus Sphenarium (Pyrgomorphidae) is a small group of grasshoppers endemic to México and Guatemala that are economically and culturally important both as a food source and as agricultural pests. However, its taxonomy has been largely neglected mainly due to its conserved interspecific external morphology and the considerable intraspecific variation in colour pattern of some taxa. Here we examined morphological as well as mitochondrial and nuclear DNA sequence data to assess the species boundaries and evolutionary history in Sphenarium. Our morphological identification and DNA sequence-based species delimitation, carried out with three different approaches (DNA barcoding, general mixed Yule-coalescent model, Bayesian species delimitation), all recovered a higher number of putative species of Sphenarium than previously recognised. We unambiguously delimit seven species, and between five and ten additional species depending on the data/method analysed. Phylogenetic relationships within the genus strongly support two main clades, one exclusively montane, the other coastal. Divergence time estimates suggest late Miocene to Pliocene ages for the origin and most of the early diversification events in the genus, which were probably influenced by the formation of the Trans-Mexican Volcanic Belt. A series of Pleistocene events could have led to the current species diversification in both montane and coastal regions. This study not only reveals an overlooked species richness for the most popular edible insect in Mexico, but also highlights the influence of the dynamic geological and climatic history of the region in shaping its current diversity. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. The 5S rDNA in two Abracris grasshoppers (Ommatolampidinae: Acrididae): molecular and chromosomal organization.

    Science.gov (United States)

    Bueno, Danilo; Palacios-Gimenez, Octavio Manuel; Martí, Dardo Andrea; Mariguela, Tatiane Casagrande; Cabral-de-Mello, Diogo Cavalcanti

    2016-08-01

    The 5S ribosomal DNA (rDNA) sequences are subject of dynamic evolution at chromosomal and molecular levels, evolving through concerted and/or birth-and-death fashion. Among grasshoppers, the chromosomal location for this sequence was established for some species, but little molecular information was obtained to infer evolutionary patterns. Here, we integrated data from chromosomal and nucleotide sequence analysis for 5S rDNA in two Abracris species aiming to identify evolutionary dynamics. For both species, two arrays were identified, a larger sequence (named type-I) that consisted of the entire 5S rDNA gene plus NTS (non-transcribed spacer) and a smaller (named type-II) with truncated 5S rDNA gene plus short NTS that was considered a pseudogene. For type-I sequences, the gene corresponding region contained the internal control region and poly-T motif and the NTS presented partial transposable elements. Between the species, nucleotide differences for type-I were noticed, while type-II was identical, suggesting pseudogenization in a common ancestor. At chromosomal point to view, the type-II was placed in one bivalent, while type-I occurred in multiple copies in distinct chromosomes. In Abracris, the evolution of 5S rDNA was apparently influenced by the chromosomal distribution of clusters (single or multiple location), resulting in a mixed mechanism integrating concerted and birth-and-death evolution depending on the unit.

  6. Comparative cytogenetic analysis of two grasshopper species of the tribe Abracrini (Ommatolampinae, Acrididae

    Directory of Open Access Journals (Sweden)

    Marília de França Rocha

    2011-01-01

    Full Text Available The grasshopper species Orthoscapheus rufipes and Eujivarus fusiformis were analyzed using several cytogenetic techniques. The karyotype of O. rufipes, described here for the first time, had a diploid number of 2n = 23, whereas E. fusiformis had a karyotype with 2n = 21. The two species showed the same mechanism of sex determination (XO type but differed in chromosome morphology. Pericentromeric blocks of constitutive heterochromatin (CH were detected in the chromosome complement of both species. CMA3/DA/DAPI staining revealed CMA3-positive blocks in CH regions in four autosomal bivalents of O. rufipes and in two of E. fusiformis. The location of active NORs differed between the two species, occurring in bivalents M6 and S9 of O. rufipes and M6 and M7 of E. fusiformsi. The rDNA sites revealed by FISH coincided with the number and position of the active NORs detected by AgNO3 staining. The variability in chromosomal markers accounted for the karyotype differentiation observed in the tribe Abracrini.

  7. Nematodes (Mermithidae parasitizing grasshoppers (Orthoptera: Acrididae in the Pampean region, Argentina

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    J. M. Rusconi

    Full Text Available Abstract This work provides the results of a survey of entomonematodes parasites of grasshoppers in grasslands of the Pampean Region, Argentina. Nymphs of Staurorhectus longicornis Giglio-Tos, Laplatacris dispar Rhen, 1939, Dichroplus elongatus Giglio-Tos, 1894 and Metaleptea brevicornis (L. (Orthoptera: Acrididae were collected. Mermithidae was the only family registered with seven species: Agamermis decaudata Cobb, Steiner and Christie, 1923, Amphimermis bonaerensis Miralles and Camino, 1983, Amphimermis dichroplusi Camino and Lange, 1997, Amphimermis ronderosi Camino and Lange, 1997, Hexamermis coclhearius Stock and Camino, 1992, Hexamermis ovistriata Stock and Camino, 1992, and Longimermis acridophila Camino and Stock, 1989. The values of parasitism ranged between 1-12%, and intensity not overcome the number of 5.0 nematodes per larva. The nematodes observed showed specificity, not registering the same species of parasite in more than one host species. The Pampean region constituted an area with high diversity of mermithids where new species could be consider as bioregulator agents of this troublesome insect pests in agricultural areas of Argentina.

  8. Chromosomal Speciation Revisited: Modes of Diversification in Australian Morabine Grasshoppers (Vandiemenella, viatica Species Group

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    Steven J. B. Cooper

    2011-03-01

    Full Text Available Chromosomal rearrangements can alter the rate and patterns of gene flow within or between species through a reduction in the fitness of chromosomal hybrids or by reducing recombination rates in rearranged areas of the genome. This concept, together with the observation that many species have structural variation in chromosomes, has led to the theory that the rearrangements may play a direct role in promoting speciation. Australian morabine grasshoppers (genus Vandiemenella, viatica species group are an excellent model for studying the role of chromosomal rearrangement in speciation because they show extensive chromosomal variation, parapatric distribution patterns, and narrow hybrid zones at their boundaries. This species group stimulated development of one of the classic chromosomal speciation models, the stasipatric speciation model proposed by White in 1968. Our population genetic and phylogeographic analyses revealed extensive non-monophyly of chromosomal races along with historical and on-going gene introgression between them. These findings suggest that geographical isolation leading to the fixation of chromosomal variants in different geographic regions, followed by secondary contact, resulted in the present day parapatric distributions of chromosomal races. The significance of chromosomal rearrangements in the diversification of the viatica species group can be explored by comparing patterns of genetic differentiation between rearranged and co-linear parts of the genome.

  9. Multiple independent colonization of the Canary Islands by the winged grasshopper genus Sphingonotus Fieber, 1852.

    Science.gov (United States)

    Husemann, Martin; Deppermann, Jana; Hochkirch, Axel

    2014-12-01

    Volcanic archipelagos represent ideal systems to study processes of colonization, differentiation and speciation. The Canary Islands are one of the best studied archipelagos, being composed of seven main islands with a well-known geological history. Most taxa have colonized these islands stepwise from the African or Iberian mainland from east to west, following their geological origin as well as the predominating wind direction and ocean currents. Furthermore, within-island radiations have been reported for several taxa. The grasshopper genus Sphingonotus is species-rich and occurs with nine fully winged species on the Canary Islands, seven of which are endemic to single or few islands. We inferred a phylogeny of these species and their North African and Iberian relatives based upon sequences of three mitochondrial genes and one nuclear gene of 136 specimens. Surprisingly, our results suggest that almost all Sphingonotus species colonized the archipelago independently from the mainland and nearly no inter-island colonization occurred. Despite their strong flight capabilities, only one pair of endemic species are closely related (S. sublaevis from Gran Canary and S. pachecoi from Lanzarote). Moreover, no within-island speciation events were detected. We hypothesize that passive wind dispersal from the African mainland was the main driver of the colonization process and that most Sphingonotus species are not able to cover inter-island distances by active flight. This, together with strong intrageneric niche overlap might explain the lack of within-island speciation in this taxon. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. The role of the host-specific grasshopper Cornops aquaticum (Orthoptera: Acrididae) as consumer of native Eichhornia crassipes (Pontederiaceae) floating meadows.

    Science.gov (United States)

    Franceschini, María Celeste; De Wysiecki, María Laura; Poi de Neiff, Alicia; Galassi, María Eugenia; Martínez Fedra, Solange

    2011-09-01

    Cornops aquaticum is a widely distributed semiaquatic grasshopper in the Neotropics. The development, feeding and oviposition of C. aquaticum take place on Pontederiaceae, especially on species of Eichhornia. Several aspects of the feeding of C. aquaticum are studied because is one of the most important herbivores of the highly invasive floating Eichhornia crassipes in native areas. The aims of this paper were: (1) to quantify the amount of E. crassipes consumed by C. aquaticum, (2) to determine the growth rate and the conversion efficiency of food ingested by this grasshopper, and (3) to determine the possible effect of consumption on E. crassipes productivity. Thirty individuals from each specific age class were used in the experiment: nymphs A, nymphs B, adult males and adult females. Insects were individually confined in plastic pots with a leaf of E. crassipes. We estimated feeding by individual, consumption index (CI), relative growth rate (GR) and efficiency of conversion of ingested food to body substance (ECI). The impact of C. aquaticum consumption on E. crassipes floating meadows was assessed with the abundance of the grasshopper, and the available data on primary production of the host plant at the study site. Food intake of C. aquaticum was 11.23% of plant productivity. Food consumption, growth rate and food conversion efficiency of this grasshopper varied according to the specific age classes. Damage caused by C. aquaticum is high in comparison with the damage caused by other semiaquatic and grassland grasshoppers, however it is not enough to prevent the growth and coverage of native E. crassipes floating meadows because abundance of grasshoppers are realtively low and the growth rate and productivity of the host plant is high.

  11. Reprodução de Lytechinus variegatus (Echinodermata: Echinoidea: efeito do ciclo lunar e características da população = Reproduction of Lytechinus variegatus (Echinodermata: Echinoidea: effect of lunar cycle and population characteristics

    Directory of Open Access Journals (Sweden)

    Alexandra Mara Cruz Lage

    2011-07-01

    Full Text Available Este estudo avaliou as características reprodutivas de uma população do ouriço do mar Lytechinus variegatus e a influência do ciclo lunar na liberação de gametas. Foram realizadas oito coletas para avaliação do índice gonadossomático (IG e dos parâmetros populacionais relacionados com a reprodução. Para avaliação do efeito da Lua na liberação de gametas foram realizadas coletas em três ciclos lunares completos. Ao todo foram coletados 295 indivíduos, sendo 156 machos e 131 fêmeas (proporção 1,19:1, porém não houve diferença significativa na proporção sexual da população. O peso dos machos foisignificativamente maior que o das fêmeas, porém não houve diferença significativa no IG, peso gonadal e diâmetro entre os sexos. Com a amplitude no diâmetro dos animais coletados (5,5-8,7 cm foram estabelecidas cinco classes de tamanho. Não houve diferençassignificativas no IG entre as classes de tamanho. Houve efeito da periodicidade lunar na liberação de gametas, com menor IG na lua nova, indicando que esta ocorre no primeiro quarto lunar e em marés de sizígia.This work evaluated the spawning of sea urchin Lytechinus variegates based on lunar cycle and population characteristics. Eight monthly collections were realized to estimate the gonadosomatic index (GI and population parameters regarding reproduction. To evaluate the effect of the lunar cycle on spawning, samples were taken for each moon phase of three lunar cycles. In the entire work 295 individuals were collected, 156 males and 131 females (1.19:1 ratio. However, there was no significant difference in the sex ratio of the population. The weight of males was significantly greater than that of females. There were no differences between males and females in gonadosomatic index (GI, gonad weight and diameter. There was aneffect of the lunar periodicity on spawning, with lower GI in new moon, indicating that spawning occurs on the first lunar quarter in spring

  12. Grasshopper Lazarillo, a GPI-anchored Lipocalin, increases Drosophila longevity and stress resistance, and functionally replaces its secreted homolog NLaz.

    Science.gov (United States)

    Ruiz, Mario; Wicker-Thomas, Claude; Sanchez, Diego; Ganfornina, Maria D

    2012-10-01

    Lazarillo (Laz) is a glycosyl-phosphatidylinositol (GPI)-linked glycoprotein first characterized in the developing nervous system of the grasshopper Schistocerca americana. It belongs to the Lipocalins, a functionally diverse family of mostly secreted proteins. In this work we test whether the protective capacity known for Laz homologs in flies and vertebrates (NLaz, GLaz and ApoD) is evolutionarily conserved in grasshopper Laz, and can be exerted from the plasma membrane in a cell-autonomous manner. First we demonstrate that extracellular forms of Laz have autocrine and paracrine protecting effects for oxidative stress-challenged Drosophila S2 cells. Then we assay the effects of overexpressing GPI-linked Laz in adult Drosophila and whether it rescues both known and novel phenotypes of NLaz null mutants. Local effects of GPI-linked Laz inside and outside the nervous system promote survival upon different stress forms, and extend lifespan and healthspan of the flies in a cell-type dependent manner. Outside the nervous system, expression in fat body cells but not in hemocytes results in protection. Within the nervous system, glial cell expression is more effective than neuronal expression. Laz actions are sexually dimorphic in some expression domains. Fat storage promotion and not modifications in hydrocarbon profiles or quantities explain the starvation-desiccation resistance caused by Laz overexpression. This effect is exerted when Laz is expressed ubiquitously or in dopaminergic cells, but not in hemocytes. Grasshopper Laz functionally restores the loss of NLaz, rescuing stress-sensitivity as well as premature accumulation of aging-related damage, monitored by advanced glycation end products (AGEs). However Laz does not rescue NLaz courtship behavioral defects. Finally, the presence of two new Lipocalins with predicted GPI-anchors in mosquitoes shows that the functional advantages of GPI-linkage have been commonly exploited by Lipocalins in the arthropodan lineage

  13. Growth and reproduction of the alpine grasshopper Miramella alpina feeding on CO2-enriched dwarf shrubs at treeline.

    Science.gov (United States)

    Asshoff, Roman; Hättenschwiler, Stephan

    2005-01-01

    The consequences for plant-insect interactions of atmospheric changes in alpine ecosystems are not well understood. Here, we tested the effects of elevated CO(2) on leaf quality in two dwarf shrub species (Vaccinium myrtillus and V. uliginosum) and the response of the alpine grasshopper (Miramella alpina) feeding on these plants in a field experiment at the alpine treeline (2,180 m a.s.l.) in Davos, Switzerland. Relative growth rates (RGR) of M. alpina nymphs were lower when they were feeding on V. myrtillus compared to V. uliginosum, and were affected by elevated CO(2) depending on plant species and nymph developmental stage. Changes in RGR correlated with CO(2)-induced changes in leaf water, nitrogen, and starch concentrations. Elevated CO(2) resulted in reduced female adult weight irrespective of plant species, and prolonged development time on V. uliginosum only, but there were no significant differences in nymphal mortality. Newly molted adults of M. alpina produced lighter eggs and less secretion (serving as egg protection) under elevated CO(2). When grasshoppers had a choice among four different plant species grown either under ambient or elevated CO(2), V. myrtillus and V. uliginosum consumption increased under elevated CO(2) in females while it decreased in males compared to ambient CO(2)-grown leaves. Our findings suggest that rising atmospheric CO(2) distinctly affects leaf chemistry in two important dwarf shrub species at the alpine treeline, leading to changes in feeding behavior, growth, and reproduction of the most important insect herbivore in this system. Changes in plant-grasshopper interactions might have significant long-term impacts on herbivore pressure, community dynamics and ecosystem stability in the alpine treeline ecotone.

  14. Haematology, Blood Chemistry and Carcass Characteristics of Growing Rabbits Fed Grasshopper Meal as a Substitute for Fish Meal

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    A. A. Njidda* and C. E. Isidahomen1

    2010-01-01

    Full Text Available An experiment was conducted to evaluate the effect of replacing fish meal with grasshopper meal on haematology, blood chemistry and carcass characteristics of growing rabbits. Forty rabbits of mixed breeds, aged 6-10 weeks, were randomly assigned to the dietary treatments in a complete randomized design with eight rabbits per treatment. The rabbits were fed with diets containing 0, 1.25, 2.50, 3.75 and 5% grasshopper meal in diets designated as T1 (control, T2, T3, T4 and T5, respectively. The experimental diets and clean drinking water were supplied ad libitum throughout the experimental period of nine weeks. At the end of the feeding trial, three rabbits per treatment were slaughtered for carcass evaluation, while blood samples were collected for analysis. The result of the experiment showed significant differences (P0.05 on haemoglobin and mean corpuscular haemoglobin concentration (MCHC. The results also revealed significant differences (P0.05 on serum albumin and total protein. The results of carcass characteristics showed significant differences among treatments (P<0.05 for slaughter weight, carcass weight, dressing percentage, skin pelt, tail, feet and abdominal fat. The slaughter weight and carcass weight were better in groups receiving 2.5% grass hopper meal (50% fish meal replacement. From the results, it can be concluded that inclusion of 2.50% grasshopper meal as a replacement for fish meal (50% replacement has no adverse effects on the haematological parameters, serum biochemistry and carcass characteristics of rabbits.

  15. Angular distribution measurement of fragment ions from a molecule using a new beamline consisting of a Grasshopper monochromator

    Science.gov (United States)

    Saito, Norio; Suzuki, Isao H.; Onuki, Hideo; Nishi, Morotake

    1989-07-01

    Optical characteristics of a new beamline consisting of a premirror, a Grasshopper monochromator, and a refocusing mirror have been investigated. The intensity of the monochromatic soft x-ray was estimated to be about 108 photons/(s 100 mA) at 500 eV with the storage electron energy of 600 MeV and the minimum slit width. This slit width provides a resolution of about 500. Angular distributions of fragment ions from an inner-shell excited nitrogen molecule have been measured with a rotatable time-of-flight mass spectrometer by using this beamline.

  16. Angular distribution measurement of fragment ions from a molecule using a new beamline consisting of a Grasshopper monochromator

    International Nuclear Information System (INIS)

    Saito, N.; Suzuki, I.H.; Onuki, H.; Nishi, M.

    1989-01-01

    Optical characteristics of a new beamline consisting of a premirror, a Grasshopper monochromator, and a refocusing mirror have been investigated. The intensity of the monochromatic soft x-ray was estimated to be about 10 8 photons/(s 100 mA) at 500 eV with the storage electron energy of 600 MeV and the minimum slit width. This slit width provides a resolution of about 500. Angular distributions of fragment ions from an inner-shell excited nitrogen molecule have been measured with a rotatable time-of-flight mass spectrometer by using this beamline

  17. Level of heat shock proteins decreases in individuals carrying B-chromosomes in the grasshopper Eyprepocnemis plorans

    DEFF Research Database (Denmark)

    Teruel, M; Sørensen, Jesper Givskov; Loeschcke, Volker

    2010-01-01

    We analyzed the effect of B-chromosome presence on expression level of heat shock protein 70 (Hsp70) in cerebral ganglion and gonad in both males and females of the grasshopper Eyprepocnemis plorans. Two natural Spanish populations, Salobreña (Granada) and Torrox (Málaga) were assayed, the former...... harbouring a neutralized (non-driving) B-chromosome (B2) and the latter a parasitic (driving) B-chromosome (B24). The analysis was performed by Western blotting, immunostaining and densitometric measuring expression level of the Hsp70 family in adult individuals. The results showed that Hsp70 levels...

  18. Correlations between potassium, rubidium and cesium ({sup 133}Cs and {sup 137}Cs) in sporocarps of Suillus variegatus in a Swedish boreal forest

    Energy Technology Data Exchange (ETDEWEB)

    Vinichuk, M., E-mail: Mykhailo.Vinichuk@slu.s [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Department of Ecology, Zhytomyr State Technological University, 103 Cherniakhovsky Str., 10005 Zhytomyr (Ukraine); Rosen, K.; Johanson, K.J. [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Dahlberg, A. [Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, P.O. Box 7026, 750 07 Uppsala (Sweden)

    2011-04-15

    An analysis of sporocarps of ectomycorrhizal fungi Suillus variegatus assessed whether cesium ({sup 133}Cs and {sup 137}Cs) uptake was correlated with potassium (K) or rubidium (Rb) uptake. The question was whether intraspecific correlations of Rb, K and {sup 133}Cs mass concentrations with {sup 137}Cs activity concentrations in sporocarps were higher within, rather than among, different fungal species, and if genotypic origin of sporocarps within a population affected uptake and correlation. Sporocarps (n = 51) from a Swedish forest population affected by the fallout after the Chernobyl accident were studied. The concentrations were 31.9 {+-} 6.79 g kg{sup -1} for K (mean {+-} SD, dwt), 0.40 {+-} 0.09 g kg{sup -1} for Rb, 8.7 {+-} 4.36 mg kg{sup -1} for {sup 133}Cs and 63.7 {+-} 24.2 kBq kg{sup -1} for {sup 137}Cs. The mass concentrations of {sup 133}Cs correlated with {sup 137}Cs activity concentrations (r = 0.61). There was correlation between both {sup 133}Cs concentrations (r = 0.75) and {sup 137}Cs activity concentrations (r = 0.44) and Rb, but the {sup 137}Cs/{sup 133}Cs isotopic ratio negatively correlated with Rb concentration. Concentrations of K and Rb were weakly correlated (r = 0.51). The {sup 133}Cs mass concentrations, {sup 137}Cs activity concentrations and {sup 137}Cs/{sup 133}Cs isotopic ratios did not correlate with K concentrations. No differences between, within or, among genotypes in S. variegatus were found. This suggested the relationships between K, Rb, {sup 133}Cs and {sup 137}Cs in sporocarps of S. variegatus is similar to other fungal species. - Highlights: {yields} We studied uptake of Cs ({sup 133}Cs and {sup 137}Cs), K and Rb by Suillus variegates sporocarps. {yields} Genotypic origin of fungus did not affect uptake of studied elements (isotopes). {yields} Genotypic origin did not affect correlation between Cs ({sup 133}Cs and {sup 137}Cs), K and Rb.

  19. Phylogeography of the endemic grasshopper genus Betiscoides (Lentulidae) in the South African Cape Floristic Region.

    Science.gov (United States)

    Matenaar, Daniela; Fingerle, Marcus; Heym, Eva; Wirtz, Sarah; Hochkirch, Axel

    2018-01-01

    Vicariance and dispersal are two important processes shaping biodiversity patterns. The South African Cape Floristic Region (CFR) is known for its high biotic diversity and endemism. However, studies on the phylogeography of endemic invertebrates in this biodiversity hotspot are still scarce. Here, we present a phylogenetic study of the flightless grasshopper genus Betiscoides, which is endemic to the CFR and strongly associated with restio plants (Restionaceae). We hypothesized that the genus originated in the southwestern part of the CFR, that differentiation within the genus is mainly an effect of vicariance and that the three known species only represent a minor fraction of the real genetic diversity of the genus. We inferred the phylogeny based on sequences of three mitochondrial and two nuclear genes from 99 Betiscoides specimens collected across the CFR. Furthermore, we conducted a SDIVA analysis to detect distributions of ancestral nodes and the possible spatial origin of these lineages. Strong differentiation among genetic lineages was shown. The ancestor of this genus was most likely distributed in the southwestern CFR. Five major lineages were detected, three of which were ancestrally distributed in the southwestern CFR. The ancestors of the two other lineages were distributed in the northern and eastern margins of the CFR. A total of 24 divergent evolutionary lineages were found, reflecting the geographical isolation of restio-dominated fynbos habitats. Dispersal played a more prominent role than expected in differentiation of Betiscoides. While the five main lineages were separated during a first phase via dispersal, differentiation occurred later and on smaller spatial scale, predominantly driven by isolation in montane refugia (i.e. vicariance). Our study also suggests that flightless insect taxa likely show high levels of differentiation in biodiversity hotspots with their taxonomy often being incomplete. Copyright © 2017 Elsevier Inc. All rights

  20. Neural representation of calling songs and their behavioral relevance in the grasshopper auditory system

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    Gundula eMeckenhäuser

    2014-12-01

    Full Text Available Acoustic communication plays a key role for mate attraction in grasshoppers. Males use songs to advertise themselves to females. Females evaluate the song pattern, a repetitive structure of sound syllables separated by short pauses, to recognize a conspecific male and as proxy to its fitness. In their natural habitat females often receive songs with degraded temporal structure. Perturbations may, for example, result from the overlap with other songs. We studied the response behavior of females to songs that show different signal degradations. A perturbation of an otherwise attractive song at later positions in the syllable diminished the behavioral response, whereas the same perturbation at the onset of a syllable did not affect song attractiveness. We applied naïve Bayes classifiers to the spike trains of identified neurons in the auditory pathway to explore how sensory evidence about the acoustic stimulus and its attractiveness is represented in the neuronal responses. We find that populations of three or more neurons were sufficient to reliably decode the acoustic stimulus and to predict its behavioral relevance from the single-trial integrated firing rate. A simple model of decision making simulates the female response behavior. It computes for each syllable the likelihood for the presence of an attractive song pattern as evidenced by the population firing rate. Integration across syllables allows the likelihood to reach a decision threshold and to elicit the behavioral response. The close match between model performance and animal behavior shows that a spike rate code is sufficient to enable song pattern recognition.

  1. DNA amount of X and B chromosomes in the grasshoppers Eyprepocnemis plorans and Locusta migratoria.

    Science.gov (United States)

    Ruiz-Ruano, F J; Ruiz-Estévez, M; Rodríguez-Pérez, J; López-Pino, J L; Cabrero, J; Camacho, J P M

    2011-01-01

    We analyzed the DNA amount in X and B chromosomes of 2 XX/X0 grasshopper species (Eyprepocnemis plorans and Locusta migratoria), by means of Feulgen image analysis densitometry (FIAD), using previous estimates in L. migratoria as standard (5.89 pg). We first analyzed spermatids of 0B males and found a bimodal distribution of integrated optical densities (IODs), suggesting that one peak corresponded to +X and the other to -X spermatids. The difference between the 2 peaks corresponded to the X chromosome DNA amount, which was 1.28 pg in E. plorans and 0.80 pg in L. migratoria. In addition, the +X peak in E. plorans gave an estimate of the C-value in this species (10.39 pg). We next analyzed diplotene cells from 1B males in E. plorans and +B males in L. migratoria (a species where Bs are mitotically unstable and no integer B number can be defined for an individual) and measured B chromosome IOD relative to X chromosome IOD, within the same cell, taking advantage of the similar degree of condensation for both positively heteropycnotic chromosomes at this meiotic stage. From this proportion, we estimated the DNA amount for 3 different B chromosome variants found in individuals from 3 E. plorans Spanish populations (0.54 pg for B1 from Saladares, 0.51 pg for B2 from Salobreña and 0.64 for B24 from Torrox). Likewise, we estimated the DNA amount of the B chromosome in L. migratoria to be 0.15 pg. To automate measurements, we wrote a GPL3 licensed Python program (pyFIA). We discuss the utility of the present approach for estimating X and B chromosome DNA amount in a variety of situations, and the meaning of the DNA amount estimates for X and B chromosomes in these 2 species. Copyright © 2011 S. Karger AG, Basel.

  2. De Novo Assembly and Characterization of the Transcriptome of Grasshopper Shirakiacris shirakii

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    Zhongying Qiu

    2016-07-01

    Full Text Available Background: The grasshopper Shirakiacris shirakii is an important agricultural pest and feeds mainly on gramineous plants, thereby causing economic damage to a wide range of crops. However, genomic information on this species is extremely limited thus far, and transcriptome data relevant to insecticide resistance and pest control are also not available. Methods: The transcriptome of S. shirakii was sequenced using the Illumina HiSeq platform, and we de novo assembled the transcriptome. Results: Its sequencing produced a total of 105,408,878 clean reads, and the de novo assembly revealed 74,657 unigenes with an average length of 680 bp and N50 of 1057 bp. A total of 28,173 unigenes were annotated for the NCBI non-redundant protein sequences (Nr, NCBI non-redundant nucleotide sequences (Nt, a manually-annotated and reviewed protein sequence database (Swiss-Prot, Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG databases. Based on the Nr annotation results, we manually identified 79 unigenes encoding cytochrome P450 monooxygenases (P450s, 36 unigenes encoding carboxylesterases (CarEs and 36 unigenes encoding glutathione S-transferases (GSTs in S. shirakii. Core RNAi components relevant to miroRNA, siRNA and piRNA pathways, including Pasha, Loquacious, Argonaute-1, Argonaute-2, Argonaute-3, Zucchini, Aubergine, enhanced RNAi-1 and Piwi, were expressed in S. shirakii. We also identified five unigenes that were homologous to the Sid-1 gene. In addition, the analysis of differential gene expressions revealed that a total of 19,764 unigenes were up-regulated and 4185 unigenes were down-regulated in larvae. In total, we predicted 7504 simple sequence repeats (SSRs from 74,657 unigenes. Conclusions: The comprehensive de novo transcriptomic data of S. shirakii will offer a series of valuable molecular resources for better studying insecticide resistance, RNAi and molecular marker discovery in the transcriptome.

  3. Morphological and colour morph clines along an altitudinal gradient in the meadow grasshopper Pseudochorthippus parallelus.

    Science.gov (United States)

    Köhler, Günter; Samietz, Jörg; Schielzeth, Holger

    2017-01-01

    Many animals show altitudinal clines in size, shape and body colour. Increases in body size and reduction in the length of body appendices in colder habitats are usually attributed to improved heat conservation at lower surface-to-volume ratios (known as Bergmann's and Allen's rule, respectively). However, the patterns are more variable and sometimes reversed in small ectotherms that are affected by shortened growing seasons. Altitude can also affect colouration. The thermal melanism hypothesis predicts darker colours under cooler conditions because of a thermoregulatory advantage. Darker colours may also be favoured at high altitudes for reasons of UV protection or habitat-dependent crypsis. We studied altitudinal variation in morphology and colour in the colour-polymorphic meadow grasshopper Pseudochorthippus parallelus based on 563 individuals from 17 populations sampled between 450 and 2,500 m asl. Pronotum length did not change with altitude, while postfemur length decreased significantly in both sexes. Tegmen (forewing) length decreased in males, but not in females. The results indicate that while body size, as best quantified by pronotum length, was remarkably constant, extended appendices were reduced at high altitudes. The pattern thus follows Allen's rule, but neither Bergmann's nor converse Bergmann's rule. These results indicate that inference of converse Bergmann's rule based on measurements from appendices should be treated with some caution. Colour morph ratios showed significant changes in both sexes from lowland populations dominated by green individuals to high-altitude populations dominated by brown ones. The increase of brown morphs was particularly steep between 1,500 and 2,000 m asl. The results suggest shared control of colour in males and females and local adaptation along the altitudinal gradient following the predictions of the thermal melanism hypothesis. Interestingly, both patterns, the reduction of body appendices and the higher

  4. Wide prevalence of hybridization in two sympatric grasshopper species may be shaped by their relative abundances.

    Science.gov (United States)

    Rohde, Katja; Hau, Yvonne; Weyer, Jessica; Hochkirch, Axel

    2015-09-16

    Hybridization between species is of conservation concern as it might threaten the genetic integrity of species. Anthropogenic factors can alter hybridization dynamics by introducing new potentially hybridizing species or by diminishing barriers to hybridization. This may even affect sympatric species pairs through environmental change, which so far has received little attention. We studied hybridization prevalence and the underlying behavioral mechanisms in two sympatric grasshopper species, a rare specialist (Chorthippus montanus) and a common generalist (Chorthippus parallelus). We conducted a mate choice experiment with constant intraspecific density and varying heterospecific density, i.e. varying relative frequency of both species. Mate choice was frequency-dependent in both species with a higher risk of cross-mating with increasing heterospecific frequency, while conspecific mating increased linearly with increasing conspecific density. This illustrates that reproductive barriers could be altered by environmental change, if the relative frequency of species pairs is affected. Moreover, we performed a microsatellite analysis to detect hybridization in twelve syntopic populations (and four allotopic populations). Hybrids were detected in nearly all syntopic populations with hybridization rates reaching up to 8.9 %. Genetic diversity increased for both species when hybrids were included in the data set, but only in the common species a positive correlation between hybridization rate and genetic diversity was detected. Our study illustrates that the relative frequency of the two species strongly determines the effectiveness of reproductive barriers and that even the more choosy species (Ch. montanus) may face a higher risk of hybridization if population size decreases and its relative frequency becomes low compared to its sister species. The asymmetric mate preferences of both species may lead to quasi-unidirectional gene flow caused by unidirectional

  5. Ontogeny of pioneer neurons in the antennal nervous system of the grasshopper Schistocerca gregaria.

    Science.gov (United States)

    Boyan, George; Ehrhardt, Erica

    2017-01-01

    The nervous system of the antenna of the grasshopper Schistocerca gregaria consists of two nerve tracts in which sensory cells project their axons to the brain. Each tract is pioneered early in embryogenesis by a pair of identified cells located apically in the antennal lumen. The pioneers are thought to originate in the epithelium of the antenna and then delaminate into the lumen where they commence axogenesis. However, unambiguous molecular identification of these cells in the epithelium, of an identifiable precursor, and of their mode of generation has been lacking. In this study, we have used immunolabeling against neuron-specific horseradish peroxidase and against Lachesin, a marker for differentiating epithelial cells, in combination with the nuclear stain DAPI, to identify the pioneers within the epithelium of the early embryonic antenna. We then track their delamination into the lumen as differentiated neurons. The pioneers are not labeled by the mesodermal/mesectodermal marker Mes3, consistent with an epithelial (ectodermal) origin. Intracellular dye injection, as well as labeling against the mitosis marker phospho-histone 3, identifies precursor cells in the epithelium, each associated with a column of cells. Culturing with the S-phase label 5-ethynyl-2'-deoxyuridine (EdU) shows that both a precursor and its column have incorporated the label, confirming a lineage relationship. Each set of pioneers can be shown to belong to a separate lineage of such epithelial cells, and the precursors remain and are proliferative after generating the pioneers. Analyses of mitotic spindle orientation then enable us to propose a model in which a precursor generates its pioneers asymmetrically via self-renewal.

  6. Preferential occupancy of R2 retroelements on the B chromosomes of the grasshopper Eyprepocnemis plorans.

    Directory of Open Access Journals (Sweden)

    Eugenia E Montiel

    Full Text Available R2 non-LTR retrotransposons exclusively insert into the 28S rRNA genes of their host, and are expressed by co-transcription with the rDNA unit. The grasshopper Eyprepocnemis plorans contains transcribed rDNA clusters on most of its A chromosomes, as well as non-transcribed rDNA clusters on the parasitic B chromosomes found in many populations. Here the structure of the E. plorans R2 element, its abundance relative to the number of rDNA units and its retrotransposition activity were determined. Animals screened from five populations contained on average over 12,000 rDNA units on their A chromosomes, but surprisingly only about 100 R2 elements. Monitoring the patterns of R2 insertions in individuals from these populations revealed only low levels of retrotransposition. The low rates of R2 insertion observed in E. plorans differ from the high levels of R2 insertion previously observed in insect species that have many fewer rDNA units. It is proposed that high levels of R2 are strongly selected against in E. plorans, because the rDNA transcription machinery in this species is unable to differentiate between R2-inserted and uninserted units. The B chromosomes of E. plorans contain an additional 7,000 to 15,000 rDNA units, but in contrast to the A chromosomes, from 150 to over 1,500 R2 elements. The higher concentration of R2 in the inactive B chromosomes rDNA clusters suggests these chromosomes can act as a sink for R2 insertions thus further reducing the level of insertions on the A chromosomes. These studies suggest an interesting evolutionary relationship between the parasitic B chromosomes and R2 elements.

  7. Morphological and colour morph clines along an altitudinal gradient in the meadow grasshopper Pseudochorthippus parallelus.

    Directory of Open Access Journals (Sweden)

    Günter Köhler

    Full Text Available Many animals show altitudinal clines in size, shape and body colour. Increases in body size and reduction in the length of body appendices in colder habitats are usually attributed to improved heat conservation at lower surface-to-volume ratios (known as Bergmann's and Allen's rule, respectively. However, the patterns are more variable and sometimes reversed in small ectotherms that are affected by shortened growing seasons. Altitude can also affect colouration. The thermal melanism hypothesis predicts darker colours under cooler conditions because of a thermoregulatory advantage. Darker colours may also be favoured at high altitudes for reasons of UV protection or habitat-dependent crypsis. We studied altitudinal variation in morphology and colour in the colour-polymorphic meadow grasshopper Pseudochorthippus parallelus based on 563 individuals from 17 populations sampled between 450 and 2,500 m asl. Pronotum length did not change with altitude, while postfemur length decreased significantly in both sexes. Tegmen (forewing length decreased in males, but not in females. The results indicate that while body size, as best quantified by pronotum length, was remarkably constant, extended appendices were reduced at high altitudes. The pattern thus follows Allen's rule, but neither Bergmann's nor converse Bergmann's rule. These results indicate that inference of converse Bergmann's rule based on measurements from appendices should be treated with some caution. Colour morph ratios showed significant changes in both sexes from lowland populations dominated by green individuals to high-altitude populations dominated by brown ones. The increase of brown morphs was particularly steep between 1,500 and 2,000 m asl. The results suggest shared control of colour in males and females and local adaptation along the altitudinal gradient following the predictions of the thermal melanism hypothesis. Interestingly, both patterns, the reduction of body appendices and

  8. Body Size Adaptations to Altitudinal Climatic Variation in Neotropical Grasshoppers of the Genus Sphenarium (Orthoptera: Pyrgomorphidae)

    Science.gov (United States)

    2015-01-01

    Altitudinal clines in body size can result from the effects of natural and sexual selection on growth rates and developing times in seasonal environments. Short growing and reproductive seasons constrain the body size that adults can attain and their reproductive success. Little is known about the effects of altitudinal climatic variation on the diversification of Neotropical insects. In central Mexico, in addition to altitude, highly heterogeneous topography generates diverse climates that can occur even at the same latitude. Altitudinal variation and heterogeneous topography open an opportunity to test the relative impact of climatic variation on body size adaptations. In this study, we investigated the relationship between altitudinal climatic variation and body size, and the divergence rates of sexual size dimorphism (SSD) in Neotropical grasshoppers of the genus Sphenarium using a phylogenetic comparative approach. In order to distinguish the relative impact of natural and sexual selection on the diversification of the group, we also tracked the altitudinal distribution of the species and trends of both body size and SSD on the phylogeny of Sphenarium. The correlative evidence suggests no relationship between altitude and body size. However, larger species were associated with places having a warmer winter season in which the temporal window for development and reproduction can be longer. Nonetheless, the largest species were also associated with highly seasonal environments. Moreover, large body size and high levels of SSD have evolved independently several times throughout the history of the group and male body size has experienced a greater evolutionary divergence than females. These lines of evidence suggest that natural selection, associated with seasonality and sexual selection, on maturation time and body size could have enhanced the diversification of this insect group. PMID:26684616

  9. Multilocus sequence typing of Metarhizium anisopliae var acridum isolates as microbial agents for locust and grasshopper control. Genbank Accession numbers FJ787311 to FJ787325

    Science.gov (United States)

    A growing interest in the biological control of locusts and grasshoppers (Acrididae) has led to the development of biopesticides based on naturally occurring pathogens which offers an environmentally safe alternative to chemical pesticides. However, the fungal strains which are being sought for biop...

  10. The Grasshopper and the Taxonomer. Use of Song and Structure in Orthoptera Saltatoria for Teaching the Principles of Taxonomy. Part 1. Field and Laboratory Exercises

    Science.gov (United States)

    Broughton, W. B.

    1972-01-01

    Describes the coordinated study of European grasshoppers as living specimens in the field and as permanent laboratory preparations for introducing taxonomic principles. Provides details for the preparation of specimens and sample instructions provided to students. Part I of a three-part series. (AL)

  11. Grasshopper populations inhabiting the B-C Cribs and REDOX Pond Sites, 200 Area Plateau, United States Energy Research and Development Administration's Hanford Reservation

    International Nuclear Information System (INIS)

    Sheldon, J.K.; Rogers, L.E.

    1976-02-01

    The purpose of this study was to determine the taxonomic composition, abundance, and food habits of grasshopper populations inhabiting the 200 Area plateau. Two sites were selected for detailed study, one near the B-C Cribs control zone and the other near the former REDOX Pond. A total of 14 grasshopper species were collected from the B-C Cribs study area and 16 species from the REDOX Pond area. Thirteen of these species occurred at both locations. Population density was low throughout most of the spring, increased in late May, and reached a peak of about 4 grasshoppers per square meter in early July. A dietary analysis showed that 7 of the 28 species of vascular plants recorded from the area were major components in grasshopper diets. These included needle-and-thread grass (Stipa comata), turpentine cymopterus (Cymopterus terebinthinus), Carey's balsamroot (Balsamorhiza careyana), western tansymustard (Descurainia pinnata), Jim Hill mustard (Sisymbrium altissimum), big sagebrush (Artemisia tridentata) and green rabbitbrush (Chrysothamnus viscidiflorus). The plant most heavily utilized was big sagebrush, followed by turpentine cymopterus, green rabbitbrush, and Carey's balsamroot. Other species were less frequently eaten. Several plants were present in the diet at a much higher frequency than they occurred in the environment, indicating that they were preferred food items.

  12. Plant DNA detection from grasshopper guts: A step-by-step protocol, from tissue preparation to obtaining plant DNA sequences1

    Science.gov (United States)

    Avanesyan, Alina

    2014-01-01

    • Premise of the study: A PCR-based method of identifying ingested plant DNA in gut contents of Melanoplus grasshoppers was developed. Although previous investigations have focused on a variety of insects, there are no protocols available for plant DNA detection developed for grasshoppers, agricultural pests that significantly influence plant community composition. • Methods and Results: The developed protocol successfully used the noncoding region of the chloroplast trnL (UAA) gene and was tested in several feeding experiments. Plant DNA was obtained at seven time points post-ingestion from whole guts and separate gut sections, and was detectable up to 12 h post-ingestion in nymphs and 22 h post-ingestion in adult grasshoppers. • Conclusions: The proposed protocol is an effective, relatively quick, and low-cost method of detecting plant DNA from the grasshopper gut and its different sections. This has important applications, from exploring plant “movement” during food consumption, to detecting plant–insect interactions. PMID:25202604

  13. Microbial community assessment of mealworm larvae (Tenebrio molitor) and grasshoppers (Locusta migratoria migratorioides) sold for human consumption.

    Science.gov (United States)

    Stoops, J; Crauwels, S; Waud, M; Claes, J; Lievens, B; Van Campenhout, L

    2016-02-01

    In Western countries, the popularity of edible insects as an alternative animal protein source is increasing. Nevertheless, there is a lack of profound insight into the microbial safety and shelf life of living insects sold for human consumption. The purpose of this study was to characterise the microflora of fresh edible mealworm larvae and grasshoppers in a quantitative and qualitative way. Therefore, culture-dependent analyses (the total viable aerobic count, Enterobacteriaceae, lactic acid bacteria, yeasts and moulds, and bacterial endospores) and next-generation sequencing (454amplicon pyrosequencing) were performed. High microbial counts were obtained for both insect species. Different insect batches resulted in quite similar microbial numbers, except for bacterial endospores. However, the bacterial community composition differed between both insect species. The most abundant operational taxonomic unit in mealworm larvae was Propionibacterium. Also members of the genera Haemophilus, Staphylococcus and Clostridium were found. Grasshoppers were mainly dominated by Weissella, Lactococcus and Yersinia/Rahnella. Overall, a variety of potential spoilage bacteria and food pathogens were characterised. The results of this study suggest that a processing step with a microbiocidal effect is required to avoid or minimize risks involved with the consumption of edible insects. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Effect of ethyl methanesulphonate and X-irradiation on the spermatocyte chromosomes of the grasshopper, Gesonula punctifrons

    International Nuclear Information System (INIS)

    Ghosh, Mita; Majumdar, K.C.; Duttagupta, A.K.

    1977-01-01

    Present investigation was performed to find out the effect of ethyl methanesulfonate (EMS) and X-irradiation on the meiotic cells of the grasshopper Gesonula punctifrons. Adult male grasshoppers were administered EMS (intraperitoneal injection) with one of the following concentration : 0.05%, 0.05% + 0.05%, 0.1%, 0.2%. Only 0.002 ml of required concentration were injected/animal and irradiated with 200R of X-ray in one acute dose/animal as per experimental schedule. Controls were injected with distilled water with a quantity 0.002 ml/animal. Treated and control animals were sacrificed 24 hours and 48 hours after treatment and the dividing spermatocytes were analysed for chromosomal aberrations. It was shown that EMS had stage spcificity as compared to the 200R of X-ray on the production of chromosome aberrations. Combined treatment of X-ray and EMS showed an additive effect compared to the individual effect of X-irradiation or EMS. (author)

  15. Investigating the functional morphology of genitalia during copulation in the grasshopper Melanoplus rotundipennis (Scudder, 1878) via correlative microscopy.

    Science.gov (United States)

    Woller, Derek A; Song, Hojun

    2017-03-01

    We investigated probable functions of the interacting genitalic components of a male and a female of the flightless grasshopper species Melanoplus rotundipennis (Scudder, 1878) (frozen rapidly during copulation) via correlative microscopy; in this case, by synergizing micro-computed tomography (micro-CT) with digital single lens reflex camera photography with focal stacking, and scanning electron microscopy. To assign probable functions, we combined imaging results with observations of live and museum specimens, and function hypotheses from previous studies, the majority of which focused on museum specimens with few investigating hypotheses in a physical framework of copulation. For both sexes, detailed descriptions are given for each of the observed genitalic and other reproductive system components, the majority of which are involved in copulation, and we assigned probable functions to these latter components. The correlative microscopy approach is effective for examining functional morphology in grasshoppers, so we suggest its use for other animals as well, especially when investigating body regions or events that are difficult to access and understand otherwise, as shown here with genitalia and copulation. J. Morphol. 278:334-359, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Neurochemical Architecture of the Central Complex Related to Its Function in the Control of Grasshopper Acoustic Communication

    Science.gov (United States)

    Kunst, Michael; Pförtner, Ramona; Aschenbrenner, Katja; Heinrich, Ralf

    2011-01-01

    The central complex selects and coordinates the species- and situation-specific song production in acoustically communicating grasshoppers. Control of sound production is mediated by several neurotransmitters and modulators, their receptors and intracellular signaling pathways. It has previously been shown that muscarinic cholinergic excitation in the central complex promotes sound production whereas both GABA and nitric oxide/cyclic GMP signaling suppress its performance. The present immunocytochemical and pharmacological study investigates the question whether GABA and nitric oxide mediate inhibition of sound production independently. Muscarinic ACh receptors are expressed by columnar output neurons of the central complex that innervate the lower division of the central body and terminate in the lateral accessory lobes. GABAergic tangential neurons that innervate the lower division of the central body arborize in close proximity of columnar neurons and thus may directly inhibit these central complex output neurons. A subset of these GABAergic tangential neurons accumulates cyclic GMP following the release of nitric oxide from neurites in the upper division of the central body. While sound production stimulated by muscarine injection into the central complex is suppressed by co-application of sodium nitroprusside, picrotoxin-stimulated singing was not affected by co-application of this nitric oxide donor, indicating that nitric oxide mediated inhibition requires functional GABA signaling. Hence, grasshopper sound production is controlled by processing of information in the lower division of the central body which is subject to modulation by nitric oxide released from neurons in the upper division. PMID:21980504

  17. Chronic toxicity test with sea urchin Echinometra lucunter and Lytechinus variegatus (Echinodermata: Echinoidea, exposed to light-stick - flag paternoster used for longline surface fishing

    Directory of Open Access Journals (Sweden)

    Caio Cesar-Ribeiro

    2010-06-01

    Full Text Available In this work, the chronic toxicity of a mixture of light-stick chemicals and water was tested. The light-stick is used in fishery activities to catch swordfish. The tubes were collected on the beaches of the Costa dos Coqueiros - BA, Brazil, in the period from 14th to 31st July 2007. The method used was a short chronic toxicity test where embryos of the sea urchins Echinometra lucunter and Lytechinus variegatus were exposed to a stock solution consisting of the supernatant formed from a mixture of sea water and the orange-colored light-stick chemical. After a preliminary test, concentrations defined were 0.002, 0.003, 0.01, 0.02, 0.1, 1.0% of stock solution. The final test ran for 36 hours for E. Lucunter and 24 hours for L. variegatus with 4 replicates for each concentration. The value of EC50 - 36h was 0.062% with confidence limits ranging from 0.042 to 0.079% and the EC50 - 24h was 0.011% with confidence limits ranging from 0.009 to 0.014%, i.e., the chemical mix present in the light-stick is potentially toxic. So, as these flags are commonly used for fishing there is potential danger in their disposal in the open ocean.O objetivo deste trabalho foi avaliar a toxicidade crônica da água do mar em contato com o líquido contido no light-stick, sinalizador utilizado em pesca de espinhel de superfície para a captura de espadarte. Os tubos foram coletados nas praias da Costa dos Coqueiros - BA, no período de 14 a 31 de Julho de 2007. O método utilizado para a verificação da toxicidade crônica foi o teste de curta duração com embriões de ouriço-do-mar Echinometra lucunter e Lytechinus variegatus, os ensaios foram realizados com solução estoque que consiste do sobrenadante formado a partir de uma mistura de água do mar com o líquido do sinalizador de coloração laranja. Após um teste preliminar as concentrações definidas foram 0.002; 0.003; 0.01; 0.02; 0.1; 1.0%. O teste definitivo teve duração de 36 horas para E. lucunter e 24

  18. Perfil hematimétrico e identificação da hemoglobina do bicho preguiça Bradypus variegatus

    OpenAIRE

    Ferrari Ramos, Francimar

    2006-01-01

    O objetivo deste estudo foi, em preguiças Bradypus variegatus, estabelecer o perfil hematimétrico e identificar os tipos de hemoglobina (Hb), além de avaliar se existe influência do sexo sobre estes parâmetros. Estudou-se 10 preguiças (6 machos e 4 fêmeas), não anestesiadas, mantidas em cativeiro, pesando (X±DP) 3,6±0,79kg e com temperatura retal média de 30±1oC. Coleta de sangue, através de punção da veia cefálica medial do membro anterior, foi obtida para realização da hematimetria, do esfr...

  19. 1436-IJBCS-Article-Rapaël Emuel Okonji

    African Journals Online (AJOL)

    Pr GATSING

    the optimum temperature was 40 oC for Z. variegatus arginase. The enzyme was stable ... the grasshopper's growth and development. (Idowu and ... 1978). Prokaryotes and lower eukaryotes that ..... reservoir in insect flight muscle, where it is.

  20. Area-wide pest management of locusts and grasshoppers: The striking similarities of problems and solutions in Africa and the United States

    International Nuclear Information System (INIS)

    Lockwood, Jeffrey A.

    2000-01-01

    Grasshoppers and locusts are among the most devastating pests of human agriculture. These insects cause serious damage to crops and forage on every arable continent, and their depredations have become the basis for legends, myths, and (in recent times) complex political and economic programmes. No pest problem spans such immense areas, with up to 8 million ha treated for rangeland grasshoppers during outbreaks in the US and 16 million km 2 prone to outbreaks of the Desert locust, Schistocerca gregaria Forskal, alone. The traditional management approach has involved extensive, regionalised control programmes, but recent trends suggest a decentralised future for grasshopper and locust management. Hence, we have a dynamic situation that presents the opportunity for a comparative analysis of the costs and benefits of an area-wide approach to pest management at different scales. As political, cultural, and communication barriers between scientists dissolve, the possibility of learning from one another's experiences (both failures and successes) promises to dramatically accelerate the rate of innovation, progress and discovery in pest management. For example, the recent advances in Reduced Agent-Area Treatments (RAAT, in which insecticide is applied to swaths, separated by untreated swaths or buffers) for management of rangeland grasshoppers in the US (Lockwood and Schell 1997) are based on the adaptation of tactics developed by African, Australian, Asian, and European scientists (Rachadi and Foucart 1996, Musuna and Mugisha 1997, Scherer and Celestin 1997, Wilps and Diop 1997, Launois and Rachadi 1997). The key to successful adaptation of management methods must begin with intellectual modesty and nationalistic humility so that the insights of non-scientists and experts from outside one's country are given respect and serious consideration. It is subsequently necessary to recognise the essential similarities and differences between land use systems and understand the

  1. A novel adipokinetic peptide from the corpus cardiacum of the primitive caeliferan pygmy grasshopper Tetrix subulata (Caelifera, Tetrigidae).

    Science.gov (United States)

    Gäde, Gerd; Šimek, Petr; Marco, Heather G

    2015-06-01

    The basal caeliferan family Tetrigidae is investigated to identify neuropeptides belonging to the adipokinetic hormone (AKH) family. The pygmy grasshopper Tetrix subulata contains in its corpus cardiacum two octapeptides as revealed by liquid chromatography coupled to electrospray ionization mass spectrometry. The less abundant peptide is the well-known Schgr-AKH-II (pELNFSTGW amide) which is suggested to be the ancestral AKH of Caelifera and Ensifera. The second peptide, Tetsu-AKH (pEFNFTPGW amide), is novel and quite unusual with its third aromatic residue at position 2. It is thought to be autapomorphic for Caelifera. Tetsu-AKH has hyperlipemic activity in T. subulata and in Schistocerca gregaria. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Ecotypic differentiation between urban and rural populations of the grasshopper Chorthippus brunneus relative to climate and habitat fragmentation.

    Science.gov (United States)

    San Martin Y Gomez, Gilles; Van Dyck, Hans

    2012-05-01

    Urbanization alters environmental conditions in multiple ways and offers an ecological or evolutionary challenge for organisms to cope with. Urban areas typically have a warmer climate and strongly fragmented herbaceous vegetation; the urban landscape matrix is often assumed to be hostile for many organisms. Here, we addressed the issue of evolutionary differentiation between urban and rural populations of an ectotherm insect, the grasshopper Chorthippus brunneus. We compared mobility-related morphology and climate-related life history traits measured on the first generation offspring of grasshoppers from urban and rural populations reared in a common garden laboratory experiment. We predicted (1) the urban phenotype to be more mobile (i.e., lower mass allocation to the abdomen, longer relative femur and wing lengths) than the rural phenotype; (2) the urban phenotype to be more warm adapted (e.g., higher female body mass); and (3) further evidence of local adaptation in the form of significant interaction effects between landscape of origin and breeding temperature. Both males and females of urban origin had significantly longer relative femur and wing lengths and lower mass allocation to the abdomen (i.e., higher investment in thorax and flight muscles) relative to individuals of rural origin. The results were overall significant but small (2-4%). Body mass and larval growth rate were much higher (+10%) in females of urban origin. For the life history traits, we did not find evidence for significant interaction effects between the landscape of origin and the two breeding temperatures. Our results point to ecotypic differentiation with urbanization for mobility-related morphology and climate-related life history traits. We argue that the warmer urban environment has an indirect effect through longer growth season rather than direct effects on the development.

  3. Molecular evidence for an old world origin of Galapagos and Caribbean band-winged grasshoppers (Acrididae: Oedipodinae: Sphingonotus.

    Directory of Open Access Journals (Sweden)

    Martin Husemann

    Full Text Available Patterns of colonization and diversification on islands provide valuable insights into evolutionary processes. Due to their unique geographic position and well known history, the Galapagos Islands are an important model system for evolutionary studies. Here we investigate the evolutionary history of a winged grasshopper genus to infer its origin and pattern of colonization in the Galapagos archipelago. The grasshopper genus Sphingonotus has radiated extensively in the Palaearctic and many species are endemic to islands. In the New World, the genus is largely replaced by the genus Trimerotropis. Oddly, in the Caribbean and on the Galapagos archipelago, two species of Sphingonotus are found, which has led to the suggestion that these might be the result of anthropogenic translocations from Europe. Here, we test this hypothesis using mitochondrial and nuclear DNA sequences from a broad sample of Sphingonotini and Trimerotropini species from the Old World and New World. The genetic data show two distinct genetic clusters representing the New World Trimerotropini and the Old World Sphingonotini. However, the Sphingonotus species from Galapagos and the Caribbean split basally within the Old World Sphingonotini lineage. The Galapagos and Caribbean species appear to be related to Old World taxa, but are not the result of recent anthropogenic translocations as revealed by divergence time estimates. Distinct genetic lineages occur on the four investigated Galapagos Islands, with deep splits among them compared to their relatives from the Palaearctic. A scenario of a past wider distribution of Sphingonotus in the New World with subsequent extinction on the mainland and replacement by Trimerotropis might explain the disjunct distribution.

  4. Molecular evidence for an old world origin of Galapagos and Caribbean band-winged grasshoppers (Acrididae: Oedipodinae: Sphingonotus).

    Science.gov (United States)

    Husemann, Martin; Habel, Jan Christian; Namkung, Suk; Hochkirch, Axel; Otte, Daniel; Danley, Patrick D

    2015-01-01

    Patterns of colonization and diversification on islands provide valuable insights into evolutionary processes. Due to their unique geographic position and well known history, the Galapagos Islands are an important model system for evolutionary studies. Here we investigate the evolutionary history of a winged grasshopper genus to infer its origin and pattern of colonization in the Galapagos archipelago. The grasshopper genus Sphingonotus has radiated extensively in the Palaearctic and many species are endemic to islands. In the New World, the genus is largely replaced by the genus Trimerotropis. Oddly, in the Caribbean and on the Galapagos archipelago, two species of Sphingonotus are found, which has led to the suggestion that these might be the result of anthropogenic translocations from Europe. Here, we test this hypothesis using mitochondrial and nuclear DNA sequences from a broad sample of Sphingonotini and Trimerotropini species from the Old World and New World. The genetic data show two distinct genetic clusters representing the New World Trimerotropini and the Old World Sphingonotini. However, the Sphingonotus species from Galapagos and the Caribbean split basally within the Old World Sphingonotini lineage. The Galapagos and Caribbean species appear to be related to Old World taxa, but are not the result of recent anthropogenic translocations as revealed by divergence time estimates. Distinct genetic lineages occur on the four investigated Galapagos Islands, with deep splits among them compared to their relatives from the Palaearctic. A scenario of a past wider distribution of Sphingonotus in the New World with subsequent extinction on the mainland and replacement by Trimerotropis might explain the disjunct distribution.

  5. What triggers colour change? Effects of background colour and temperature on the development of an alpine grasshopper.

    Science.gov (United States)

    Valverde, J Pablo; Schielzeth, Holger

    2015-08-21

    Colour polymorphisms are a fascinating facet of many natural populations of plants and animals, and the selective processes that maintain such variation are as relevant as the processes which promote their development. Orthoptera, the insect group that encompasses grasshoppers and bush crickets, includes a particularly large number of species that are colour polymorphic with a marked green-brown polymorphism being particularly widespread. Colour polymorphism has been associated with the need for crypsis and background matching and background-dependent homochromy has been described in a few species. However, when and how different environmental conditions influence variation in colour remains poorly understood. Here we test for effects of background colour and ambient temperature on the occurrence of colour morph switches (green to brown or brown to green) and developmental darkening in the alpine dwelling club-legged grasshopper Gomphocerus sibiricus. We monitored individually housed nymphae across three of their four developmental stages and into the first week after final ecdysis. Our data show an absence of colour morph switches in G. sibiricus, without a single switch observed in our sample. Furthermore, we test for an effect of temperature on colouration by manipulating radiant heat, a limiting factor in alpine habitats. Radiant heat had a significant effect on developmental darkening: individuals under low radiant heat tended to darken, while individuals under high radiant heat tended to lighten within nymphal stages. Young imagoes darkened under either condition. Our results indicate a plastic response to a variable temperature and indicate that melanin, a multipurpose pigment responsible for dark colouration and presumed to be costly, seems to be strategically allocated according to the current environmental conditions. Unlike other orthopterans, the species is apparently unable to switch colour morphs (green/brown) during development, suggesting that

  6. Inferring the demographic history of an oligophagous grasshopper: Effects of climatic niche stability and host-plant distribution.

    Science.gov (United States)

    Noguerales, Víctor; Cordero, Pedro J; Ortego, Joaquín

    2018-01-01

    Understanding the consequences of past environmental changes on the abiotic and biotic components of the landscape and deciphering their impacts on the demographic trajectories of species is a major issue in evolutionary biogeography. In this study, we combine nuclear and mitochondrial genetic data to study the phylogeographical structure and lineage-specific demographic histories of the scrub-legume grasshopper (Chorthippus binotatus binotatus), a montane taxon distributed in the Iberian Peninsula and France that exclusively feeds on certain scrub-legume species. Genetic data and paleo-distribution modelling indicate the presence of four main lineages that seem to have diverged in allopatry and long-term persisted in Iberian and French refugia since the Mid Pleistocene. Comparisons of different demographic hypotheses in an Approximate Bayesian Computation (ABC) framework supported a population bottleneck in the northwestern French clade and paleo-distribution modelling indicate that the populations of this lineage have experienced more severe environmental fluctuations during the last 21 000 years than those from the Iberian Peninsula. Accordingly, we found that nuclear genetic diversity of the populations of scrub-legume grasshopper is positively associated with local stability of suitable habitats defined by both Pleistocene climate changes and historical distributional shifts of host-plant species. Overall, our study highlights the importance of integrating the potential effects of abiotic (i.e. climate and geography) and biotic components (i.e. inter-specific interactions) into the study of the evolutionary and demographic history of specialist taxa with narrow ecological requirements. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Camouflage Effects of Various Colour-Marking Morphs against Different Microhabitat Backgrounds in a Polymorphic Pygmy Grasshopper Tetrix japonica

    Science.gov (United States)

    Tsurui, Kaori; Honma, Atsushi; Nishida, Takayoshi

    2010-01-01

    Background Colour-marking polymorphism is widely distributed among cryptic species. To account for the adaptive significance of such polymorphisms, several hypotheses have been proposed to date. Although these hypotheses argue over the degree of camouflage effects of marking morphs (and the interactions between morphs and their microhabitat backgrounds), as far as we know, most empirical evidence has been provided under unnatural conditions (i.e., using artificial prey). Methodology/Principal Findings Tetrix japonica, a pygmy grasshopper, is highly polymorphic in colour-markings and occurs in both sand and grass microhabitats. Even within a microhabitat, T. japonica is highly polymorphic. Using humans as dummy predators and printed photographs in which various morphs of grasshoppers were placed against different backgrounds, we addressed three questions to test the neutral, background heterogeneity, and differential crypsis hypotheses in four marking-type morphs: 1) do the morphs differ in the degree of crypsis in each microhabitat, 2) are different morphs most cryptic in specific backgrounds of the microhabitats, and 3) does the morph frequency reflect the degree of crypsis? Conclusions/Significance The degree of camouflage differed among the four morphs; therefore, the neutral hypothesis was rejected. Furthermore, the order of camouflage advantage among morphs differed depending on the two types of backgrounds (sand and grass), although the grass background consistently provided greater camouflage effects. Thus, based on our results, we could not reject the background heterogeneity hypothesis. Under field conditions, the more cryptic morphs comprised a minority of the population. Overall, our results demonstrate that the different morphs were not equivalent in the degree of crypsis, but the degree of camouflage of the morphs was not consistent with the morph frequency. These findings suggest that trade-offs exist between the camouflage benefit of body colouration

  8. Influence of different envelope maskers on signal recognition and neuronal representation in the auditory system of a grasshopper.

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    Daniela Neuhofer

    Full Text Available BACKGROUND: Animals that communicate by sound face the problem that the signals arriving at the receiver often are degraded and masked by noise. Frequency filters in the receiver's auditory system may improve the signal-to-noise ratio (SNR by excluding parts of the spectrum which are not occupied by the species-specific signals. This solution, however, is hardly amenable to species that produce broad band signals or have ears with broad frequency tuning. In mammals auditory filters exist that work in the temporal domain of amplitude modulations (AM. Do insects also use this type of filtering? PRINCIPAL FINDINGS: Combining behavioural and neurophysiological experiments we investigated whether AM filters may improve the recognition of masked communication signals in grasshoppers. The AM pattern of the sound, its envelope, is crucial for signal recognition in these animals. We degraded the species-specific song by adding random fluctuations to its envelope. Six noise bands were used that differed in their overlap with the spectral content of the song envelope. If AM filters contribute to reduced masking, signal recognition should depend on the degree of overlap between the song envelope spectrum and the noise spectra. Contrary to this prediction, the resistance against signal degradation was the same for five of six masker bands. Most remarkably, the band with the strongest frequency overlap to the natural song envelope (0-100 Hz impaired acceptance of degraded signals the least. To assess the noise filter capacities of single auditory neurons, the changes of spike trains as a function of the masking level were assessed. Increasing levels of signal degradation in different frequency bands led to similar changes in the spike trains in most neurones. CONCLUSIONS: There is no indication that auditory neurones of grasshoppers are specialized to improve the SNR with respect to the pattern of amplitude modulations.

  9. Camouflage effects of various colour-marking morphs against different microhabitat backgrounds in a polymorphic pygmy grasshopper Tetrix japonica.

    Science.gov (United States)

    Tsurui, Kaori; Honma, Atsushi; Nishida, Takayoshi

    2010-07-06

    Colour-marking polymorphism is widely distributed among cryptic species. To account for the adaptive significance of such polymorphisms, several hypotheses have been proposed to date. Although these hypotheses argue over the degree of camouflage effects of marking morphs (and the interactions between morphs and their microhabitat backgrounds), as far as we know, most empirical evidence has been provided under unnatural conditions (i.e., using artificial prey). Tetrix japonica, a pygmy grasshopper, is highly polymorphic in colour-markings and occurs in both sand and grass microhabitats. Even within a microhabitat, T. japonica is highly polymorphic. Using humans as dummy predators and printed photographs in which various morphs of grasshoppers were placed against different backgrounds, we addressed three questions to test the neutral, background heterogeneity, and differential crypsis hypotheses in four marking-type morphs: 1) do the morphs differ in the degree of crypsis in each microhabitat, 2) are different morphs most cryptic in specific backgrounds of the microhabitats, and 3) does the morph frequency reflect the degree of crypsis? The degree of camouflage differed among the four morphs; therefore, the neutral hypothesis was rejected. Furthermore, the order of camouflage advantage among morphs differed depending on the two types of backgrounds (sand and grass), although the grass background consistently provided greater camouflage effects. Thus, based on our results, we could not reject the background heterogeneity hypothesis. Under field conditions, the more cryptic morphs comprised a minority of the population. Overall, our results demonstrate that the different morphs were not equivalent in the degree of crypsis, but the degree of camouflage of the morphs was not consistent with the morph frequency. These findings suggest that trade-offs exist between the camouflage benefit of body colouration and other fitness components, providing a better understanding of

  10. Camouflage effects of various colour-marking morphs against different microhabitat backgrounds in a polymorphic pygmy grasshopper Tetrix japonica.

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    Kaori Tsurui

    2010-07-01

    Full Text Available Colour-marking polymorphism is widely distributed among cryptic species. To account for the adaptive significance of such polymorphisms, several hypotheses have been proposed to date. Although these hypotheses argue over the degree of camouflage effects of marking morphs (and the interactions between morphs and their microhabitat backgrounds, as far as we know, most empirical evidence has been provided under unnatural conditions (i.e., using artificial prey.Tetrix japonica, a pygmy grasshopper, is highly polymorphic in colour-markings and occurs in both sand and grass microhabitats. Even within a microhabitat, T. japonica is highly polymorphic. Using humans as dummy predators and printed photographs in which various morphs of grasshoppers were placed against different backgrounds, we addressed three questions to test the neutral, background heterogeneity, and differential crypsis hypotheses in four marking-type morphs: 1 do the morphs differ in the degree of crypsis in each microhabitat, 2 are different morphs most cryptic in specific backgrounds of the microhabitats, and 3 does the morph frequency reflect the degree of crypsis?The degree of camouflage differed among the four morphs; therefore, the neutral hypothesis was rejected. Furthermore, the order of camouflage advantage among morphs differed depending on the two types of backgrounds (sand and grass, although the grass background consistently provided greater camouflage effects. Thus, based on our results, we could not reject the background heterogeneity hypothesis. Under field conditions, the more cryptic morphs comprised a minority of the population. Overall, our results demonstrate that the different morphs were not equivalent in the degree of crypsis, but the degree of camouflage of the morphs was not consistent with the morph frequency. These findings suggest that trade-offs exist between the camouflage benefit of body colouration and other fitness components, providing a better

  11. Linear dose-response of acentric chromosome fragments down to 1 R of x-rays in grasshopper neuroblasts, a potential mutagen-test system

    International Nuclear Information System (INIS)

    Gaulden, M.E.; Read, C.B.

    1978-01-01

    Grasshopper-embryo neuroblasts have no spontaneous chromosome breakage; therefore they permit easy detection of agents that break chromosomes. An X-ray exposure of 1 R induces in them a detectable number of chromosome fragments. The dose-response of acentric fragment frequency fits a linear model between 0 and 128 R. Thus another cell type is added to those previously demonstrated to have no threshold dose for the induction of chromosome or gene mutations

  12. Biological and ecological evidences suggest Stipa krylovii (Pooideae), contributes to optimal growth performance and population distribution of the grasshopper Oedaleus asiaticus.

    Science.gov (United States)

    Huang, X B; McNeill, M R; Ma, J C; Qin, X H; Tu, X B; Cao, G C; Wang, G J; Nong, X Q; Zhang, Z H

    2017-06-01

    Oedaleus asiaticus Bey. Bienko is a significant grasshopper pest species occurring in north Asian grasslands. Outbreaks often result in significant loss in grasses and economic losses. Interestingly, we found this grasshopper was mainly restricted to Stipa-dominated grassland. We suspected this may be related to the dominant grasses species, Stipa krylovii Roshev, and hypothesized that S. krylovii contributes to optimal growth performance and population distribution of O. asiaticus. A 4 year investigation showed that O. asiaticus density was positively correlated to the above-ground biomass of S. krylovii and O. asiaticus growth performance variables (survival rate, size, growth rate) were significantly higher in Stipa-dominated grassland. A feeding trial also showed that O. asiaticus had a higher growth performance when feeding exclusively on S. krylovii. In addition, the choice, consumption and the efficiency of conversion of ingested food (ECI) by O. asiaticus was highest for S. krylovii compared with other plant species found in the Asian grasslands. These ecological and biological traits revealed why O. asiaticus is strongly associated with Stipa-dominated grasslands. We concluded that the existence of S. krylovii benefited the growth performance and explained the distribution of O. asiaticus. These results are useful for improved pest management strategies and developing guidelines for the monitoring of grasshopper population dynamics against the background of vegetation succession and changing plant communities in response to activities such as grazing, fire and climate change.

  13. INVENTAIRE DE L'ENTOMOFAUNE ET LUTTE CHIMIQUE ...

    African Journals Online (AJOL)

    SECRETARIAT

    Coléoptères. Sur certaines plantes, des feuilles présentant un aspect de filet ou de grillage occasionné par des criquets (Zonocerus variegatus). Certaines feuilles sont recro- quevillées suite aux piqûres de fourmis. (Camponotus sp.) et des pucerons. Figure 1 : Vue d'un pied mort de Lippia multiflora causés par les termites.

  14. Life history attributes of Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus) and comparisons with other North American subspecies

    Science.gov (United States)

    Ruth, Janet M.

    2017-01-01

    Ammodramus savannarum ammolegus—commonly referred to as the Arizona Grasshopper Sparrow—occurs in the desert and plains grasslands of southeastern Arizona, southwestern New Mexico, and northern Sonora, Mexico. Although a subspecies of conservation concern, this is the first intensive study of its life history and breeding ecology, providing baseline data and facilitating comparisons with other North American Grasshopper Sparrow subspecies. Specifically, I found A. s. ammolegus males generally weighed less than other subspecies (16.0 ± 0.8 g) but with intermediate exposed culmen length (11.6 ± 0.5 mm) and wing chord length similar to the other two migratory subspecies (62.7 ± 1.5 mm). Territory size for A. s. ammolegus was 0.72 ± 0.37 ha, with some variation between sites and among years, possibly indicating variation in habitat quality across spatial and temporal scales. The return rate for A. s. ammolegus males was 39.2%. Nest initiation for A. s. ammolegus was early to mid-July after the monsoons had begun. Domed nests were constructed on the ground, primarily under native bunch grasses, and frequently with a tunnel extending beyond the nest rim, with nest openings oriented north. Clutch size was 3.97 ± 0.68, with no evidence of Brown-headed Cowbird (Molothrus ater) nest parasitism. Extreme climate factors in the arid Southwest may have affected the life history and morphology of A. s. ammolegus as compared to other subspecies, influencing body size and mass, culmen length, breeding phenology, and nest orientation. Other geographic variation occurred in return rates, clutch size, and nest parasitism rates. The baseline data for A. s. ammolegus obtained in this study will inform future taxonomic and ecological studies as well as conservation planning. Comparisons of A. s. ammolegus morphometrics with those of other subspecies will assist field biologists in distinguishing among subspecies where they overlap, especially on wintering grounds.

  15. Discrimination of acoustic communication signals by grasshoppers (Chorthippus biguttulus): temporal resolution, temporal integration, and the impact of intrinsic noise.

    Science.gov (United States)

    Ronacher, Bernhard; Wohlgemuth, Sandra; Vogel, Astrid; Krahe, Rüdiger

    2008-08-01

    A characteristic feature of hearing systems is their ability to resolve both fast and subtle amplitude modulations of acoustic signals. This applies also to grasshoppers, which for mate identification rely mainly on the characteristic temporal patterns of their communication signals. Usually the signals arriving at a receiver are contaminated by various kinds of noise. In addition to extrinsic noise, intrinsic noise caused by stochastic processes within the nervous system contributes to making signal recognition a difficult task. The authors asked to what degree intrinsic noise affects temporal resolution and, particularly, the discrimination of similar acoustic signals. This study aims at exploring the neuronal basis for sexual selection, which depends on exploiting subtle differences between basically similar signals. Applying a metric, by which the similarities of spike trains can be assessed, the authors investigated how well the communication signals of different individuals of the same species could be discriminated and correctly classified based on the responses of auditory neurons. This spike train metric yields clues to the optimal temporal resolution with which spike trains should be evaluated. (c) 2008 APA, all rights reserved

  16. FOOD CONSUMPTION AND UTILISATION OF THE GRASSHOPPER CHROTOGONUS LUGUBRIS BLANCHARD (ORTHOPTERA, ACRIDOIDEA, PYRGOMORPHIDAE AND ITS EFFECT ON THE EGG DEPOSITION

    Directory of Open Access Journals (Sweden)

    K RAHMAN

    2002-05-01

    Full Text Available The grasshopper is found all the year round. It is considered as a pest for seedlings. The consumption index differed significantly between groups fed on different diets. Mated females consume more food than virgin females or virgin males. The highest values were recorded for the bean seedlings fed groups indicating some inadequacy in the nutritional value of bean. The growth rate was the highest in clover fed groups. Insects were able to digest bean and clover more efficiently than either wheat seedlings or cotton leaves. The growth rate was accompanied with a higher C.I. in bean, wheat, and cotton indicating that most of these food was excreted. The ECD and ECI were significantly higher in clover fed groups. This indicated that clover was utilised efficiently than the other groups. The different food stuff affected the egg production which could be attributed to the nutritional efficiencies of these diets. The preovipositional period and number of egg-pods were also affected. The number of abnormal egg-pods was the highest in the bean seedlings fed groups.

  17. The effect of discontinuous gas exchange on respiratory water loss in grasshoppers (Orthoptera: Acrididae) varies across an aridity gradient.

    Science.gov (United States)

    Huang, Shu-Ping; Talal, Stav; Ayali, Amir; Gefen, Eran

    2015-08-01

    The significance of discontinuous gas-exchange cycles (DGC) in reducing respiratory water loss (RWL) in insects is contentious. Results from single-species studies are equivocal in their support of the classic 'hygric hypothesis' for the evolution of DGC, whereas comparative analyses generally support a link between DGC and water balance. In this study, we investigated DGC prevalence and characteristics and RWL in three grasshopper species (Acrididae, subfamily Pamphaginae) across an aridity gradient in Israel. In order to determine whether DGC contributes to a reduction in RWL, we compared the DGC characteristics and RWL associated with CO2 release (transpiration ratio, i.e. the molar ratio of RWL to CO2 emission rates) among these species. Transpiration ratios of DGC and continuous breathers were also compared intraspecifically. Our data show that DGC characteristics, DGC prevalence and the transpiration ratios correlate well with habitat aridity. The xeric-adapted Tmethis pulchripennis exhibited a significantly shorter burst period and lower transpiration ratio compared with the other two mesic species, Ocneropsis bethlemita and Ocneropsis lividipes. However, DGC resulted in significant water savings compared with continuous exchange in T. pulchripennis only. These unique DGC characteristics for T. pulchripennis were correlated with its significantly higher mass-specific tracheal volume. Our data suggest that the origin of DGC may not be adaptive, but rather that evolved modulation of cycle characteristics confers a fitness advantage under stressful conditions. This modulation may result from morphological and/or physiological modifications. © 2015. Published by The Company of Biologists Ltd.

  18. Do Exogenous DNA Double-Strand Breaks Change Incomplete Synapsis and Chiasma Localization in the Grasshopper Stethophyma grossum?

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    Adela Calvente

    Full Text Available Meiotic recombination occurs as a programmed event that initiates by the formation of DNA double-strand breaks (DSBs that give rise to the formation of crossovers that are observed as chiasmata. Chiasmata are essential for the accurate chromosome segregation and the generation of new combinations of parental alleles. Some treatments that provoke exogenous DSBs also lead to alterations in the recombination pattern of some species in which full homologous synapsis is achieved at pachytene. We have carried out a similar approach in males of the grasshopper Stethophyma grossum, whose homologues show incomplete synapsis and proximal chiasma localization. After irradiating males with γ rays we have studied the distribution of both the histone variant γ-H2AX and the recombinase RAD51. These proteins are cytological markers of DSBs at early prophase I. We have inferred synaptonemal complex (SC formation via identification of SMC3 and RAD 21 cohesin subunits. Whereas thick and thin SMC3 filaments would correspond to synapsed and unsynapsed regions, the presence of RAD21 is only restricted to synapsed regions. Results show that irradiated spermatocytes maintain restricted synapsis between homologues. However, the frequency and distribution of chiasmata in metaphase I bivalents is slightly changed and quadrivalents were also observed. These results could be related to the singular nuclear polarization displayed by the spermatocytes of this species.

  19. Do Exogenous DNA Double-Strand Breaks Change Incomplete Synapsis and Chiasma Localization in the Grasshopper Stethophyma grossum?

    Science.gov (United States)

    Calvente, Adela; Santos, Juan Luis; Rufas, Julio S

    2016-01-01

    Meiotic recombination occurs as a programmed event that initiates by the formation of DNA double-strand breaks (DSBs) that give rise to the formation of crossovers that are observed as chiasmata. Chiasmata are essential for the accurate chromosome segregation and the generation of new combinations of parental alleles. Some treatments that provoke exogenous DSBs also lead to alterations in the recombination pattern of some species in which full homologous synapsis is achieved at pachytene. We have carried out a similar approach in males of the grasshopper Stethophyma grossum, whose homologues show incomplete synapsis and proximal chiasma localization. After irradiating males with γ rays we have studied the distribution of both the histone variant γ-H2AX and the recombinase RAD51. These proteins are cytological markers of DSBs at early prophase I. We have inferred synaptonemal complex (SC) formation via identification of SMC3 and RAD 21 cohesin subunits. Whereas thick and thin SMC3 filaments would correspond to synapsed and unsynapsed regions, the presence of RAD21 is only restricted to synapsed regions. Results show that irradiated spermatocytes maintain restricted synapsis between homologues. However, the frequency and distribution of chiasmata in metaphase I bivalents is slightly changed and quadrivalents were also observed. These results could be related to the singular nuclear polarization displayed by the spermatocytes of this species.

  20. Population genetic structure of the grasshopper Eyprepocnemis plorans in the south and east of the Iberian Peninsula.

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    María Inmaculada Manrique-Poyato

    Full Text Available The grasshopper Eyprepocnemis plorans subsp. plorans harbors a very widespread polymorphism for supernumerary (B chromosomes which appear to have arisen recently. These chromosomes behave as genomic parasites because they are harmful for the individuals carrying them and show meiotic drive in the initial stages of population invasion. The rapid increase in B chromosome frequency at intrapopulation level is thus granted by meiotic drive, but its spread among populations most likely depends on interpopulation gene flow. We analyze here the population genetic structure in 10 natural populations from two regions (in the south and east of the Iberian Peninsula. The southern populations were coastal whereas the eastern ones were inland populations located at 260-655 m altitude. The analysis of 97 ISSR markers revealed significant genetic differentiation among populations (average G(ST = 0.129, and the Structure software and AMOVA indicated a significant genetic differentiation between southern and eastern populations. There was also significant isolation by distance (IBD between populations. Remarkably, these results were roughly similar to those found when only the markers showing low or no dropout were included, suggesting that allelic dropout had negligible effects on population genetic analysis. We conclude that high gene flow helped this parasitic B chromosome to spread through most of the geographical range of the subspecies E. plorans plorans.

  1. Faunistic analyses of grasshoppers (Orthoptera, Acridoidea in a florest fragment near the Uruguay River, Chapecó, Santa Catarina, Brazil

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    Maria Kátia Matiotti da Costa

    2005-11-01

    Full Text Available The objective of the work was to describe the grasshopper community (Orthoptera and Acridoidea through the analysis of the fauna, in the Lajeado Monte Alegre region, on the bank of the Uruguay River, in the town of Chapecó, Santa Catarina. The collections were carried out on weekly basis, from October 2001 to September 2002, with the use of ground traps, buttnets, insect umbrellas and collections from leaves. The rates of abundance, frequency, constancy, dominance and diversity were measured. In total, 713 acridoids were collected, corresponding to 18 species, 17 genera, and 3 families. From the Acrididae family 13 species were sampled: Abracris flavolienata, Allotruxalis strigata, Amblytropidia sola, Amblytropidia sp., Cylindrotettix chacoensis, Dichroplus misionensis, Eurotettix lilloanus, Metaleptea brevicornis adspersa, Orphulella punctata, Parorphula graminea, Rhammatocerus brunneri, Ronderosia bergi and Schistocerca flavofasciata. From the Romaleidae family, 4 species: Staleochlora viridicata, Chromacris speciosa, Zoniopoda tarsata and Xyleus discoideus. From the Tridactylidae family, 2 unidentified nymphs were collected. The dominant species was A. strigata.

  2. B-chromosome effects on Hsp70 gene expression does not occur at transcriptional level in the grasshopper Eyprepocnemis plorans.

    Science.gov (United States)

    Navarro-Domínguez, Beatriz; Cabrero, Josefa; Camacho, Juan Pedro M; López-León, María Dolores

    2016-10-01

    As intragenomic parasites, B chromosomes can elicit stress in the host genome, thus inducing a response for host adaptation to this kind of continuous parasitism. In the grasshopper Eyprepocnemis plorans, B-chromosome presence has been previously associated with a decrease in the amount of the heat-shock protein 70 (HSP70). To investigate whether this effect is already apparent at transcriptional level, we analyze the expression levels of the Hsp70 gene in gonads and somatic tissues of males and females with and without B chromosomes from two populations, where the predominant B chromosome variants (B2 and B24) exhibit different levels of parasitism, by means of quantitative real-time PCR (qPCR) on complementary DNA (cDNA). The results revealed the absence of significant differences for Hsp70 transcripts associated with B-chromosome presence in virtually all samples. This indicates that the decrease in HSP70 protein levels, formerly reported in this species, may not be a consequence of transcriptional down-regulation of Hsp70 genes, but the result of post-transcriptional regulation. These results will help to design future studies oriented to identifying factors modulating Hsp70 expression, and will also contribute to uncover the biological role of B chromosomes in eukaryotic genomes.

  3. SEROSURVEY OF SELECTED ARBOVIRAL PATHOGENS IN FREE-RANGING, TWO-TOED SLOTHS (CHOLOEPUS HOFFMANNI) AND THREE-TOED SLOTHS (BRADYPUS VARIEGATUS) IN COSTA RICA, 2005–07

    Science.gov (United States)

    Medlin, Scott; Deardorff, Eleanor R.; Hanley, Christopher S.; Vergneau-Grosset, Claire; Siudak-Campfield, Asia; Dallwig, Rebecca; Travassos da Rosa, Amelia; Tesh, Robert B.; Pia Martin, Maria; Weaver, Scott C.; Vaughan, Christopher; Ramirez, Oscar; Sladky, Kurt K.; Paul-Murphy, Joanne

    2016-01-01

    We screened for antibodies to 16 arboviruses in four populations of free-ranging sloths in Costa Rica. Blood samples were taken from 16 Hoffman’s two-toed sloths (HTSs; CHOLOEPUS HOFFMANNI) and 26 brown-throated sloths (BTSs; BRADYPUS VARIEGATUS) over a 3-yr period. We used serologic assays to detect antibodies against 10 arboviruses previously described in sloths (St. Louis encephalitis [SLEV], Changuinola, Venezuelan equine encephalitis, Ilheus [ILHV], Oropouche, Mayaro, Utinga, Murutucu, Punta Toro, and vesicular stomatitis [VSV] viruses) and six arboviruses not described in sloths (Rio Grande, West Nile [WNV], eastern equine encephalitis, Piry, Munguba, and La Crosse viruses). Overall, 80% of sloths had detectable antibodies to SLEV, 67% had antibodies to ILHV, 32% to Punta Toro virus, 30% to Changuinola virus, 15% to WNV, 14% to VSV, 11% to Venezuelan equine encephalitis virus, and 10% to Rio Grande virus. No samples had detectable antibodies to the remaining eight viruses. We found a significant increase in prevalence of antibody to VSV in HTSs between 2005 and 2007, and for WNV antibody between 2005 and 2006. We found no significant differences in the prevalences of antibodies to the sampled viruses between the two locations. Antibody prevalences were significantly higher in HTSs than in BTSs for SLEV in 2005. Antibody-positive results for ILHV were likely due to cross-reaction with SLEV. The novel finding of antibodies to Rio Grande virus in sloths could be due to cross-reaction with another phlebovirus. These findings might have implications for land management and domestic animal health. Due to the nature of the study, we could not determine whether sloths could represent amplification hosts for these viruses, or whether they were only exposed and could be used as sentinel species. Further studies are needed to fully characterize arboviral exposure in sloths. PMID:27479900

  4. The comparative phylogeography of east coast estuarine fishes in formerly glaciated sites: Persistence versus recolonization in Cyprinodon variegatus ovinus and Fundulus heteroclitus macrolepidotus.

    Science.gov (United States)

    Haney, Robert A; Dionne, Michelle; Puritz, Jon; Rand, David M

    2009-01-01

    Species distributions may be dramatically affected by climatic variability, such as occurred during Pleistocene glaciation. Populations of coastal organisms could have been affected directly by ice movement or through sea level change. Response could involve shifts in distribution southwards or persistence through the full range or in limited high-latitude refugia. Comparative studies of the response of ecologically similar species can provide a useful complement to those examining response across disparate species in defining what parameters influence persistence. Patterns of mitochondrial genetic variation in 2 estuarine fish subspecies from the Northwest Atlantic, Fundulus heteroclitus macrolepidotus and Cyprinodon variegatus ovinus, indicate that ecological similarity does not necessarily predict propensity for glacial persistence. Fundulus heteroclitus macrolepidotus is highly diverse in glaciated regions, with isolated populations whose origins predate the last glacial maximum and may have recently expanded it's range to the south from New England. However, within glaciated regions, signals of population growth and distributional shifts indicate a dynamic Pleistocene history for F. h. macrolepidotus, in contrast with recent studies involving microsatellites. A different pattern is found in C. v. ovinus, which is depauperate in formerly glaciated sites, with a clear signal of recent recolonization of glaciated regions from the south. Genetic differentiation in glaciated areas is consistent with isolation after glacial withdrawal. In C. v. ovinus, rapidly evolving microsatellite loci show a similar pattern to mitochondrial DNA but may be reaching equilibrium on small spatial scales. These contrasting patterns of variation illustrate how ecologically similar species can respond to large-scale environmental change in distinct ways.

  5. Presencia de Malameba locustae (Protozoa: Rhizopoda en acridios (Orthoptera: Acrididae de la provincia de Misiones, Argentina Presence of Malameba locustae (Protozoa: Rhizopoda in grasshoppers (Orthoptera: Acrididae of Misiones province, Argentina

    Directory of Open Access Journals (Sweden)

    Carlos E. Lange

    2004-07-01

    Full Text Available La ameba patógena Malameba locustae King y Taylor fue detectada parasitando ejemplares del acridio Ronderosia bergi (Stal recolectados en las cercanías del Parque Nacional Iguazú, Misiones. El hallazgo constituye el segundo registro de M. locustae para acridios sudamericanos.Individuals of the grasshopper Ronderosia bergi (Stal collected in the surroundings of Iguazú National Park, Misiones, were found to be parasitized by the pathogenic amoeba Malameba locustae King & Taylor. The finding constitutes the second record of M. locustae for southamerican grasshoppers.

  6. The role of the host-specific grasshopper Cornops aquaticum (Orthoptera: Acrididae as consumer of native Eichhornia crassipes (Pontederiaceae floating meadows

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    María Celeste Franceschini

    2011-09-01

    Full Text Available Cornops aquaticum is a widely distributed semiaquatic grasshopper in the Neotropics. The development, feeding and oviposition of C. aquaticum take place on Pontederiaceae, especially on species of Eichhornia. Several aspects of the feeding of C. aquaticum are studied because is one of the most important herbivores of the highly invasive floating Eichhornia crassipes in native areas. The aims of this paper were: (1 to quantify the amount of E. crassipes consumed by C. aquaticum, (2 to determine the growth rate and the conversion efficiency of food ingested by this grasshopper, and (3 to determine the possible effect of consumption on E. crassipes productivity. Thirty individuals from each specific age class were used in the experiment: nymphs A, nymphs B, adult males and adult females. Insects were individually confined in plastic pots with a leaf of E. crassipes. We estimated feeding by individual, consumption index (CI, relative growth rate (GR and efficiency of conversion of ingested food to body substance (ECI. The impact of C. aquaticum consumption on E. crassipes floating meadows was assessed with the abundance of the grasshopper, and the available data on primary production of the host plant at the study site. Food intake of C. aquaticum was 11.23% of plant productivity. Food consumption, growth rate and food conversion efficiency of this grasshopper varied according to the specific age classes. Damage caused by C. aquaticum is high in comparison with the damage caused by other semiaquatic and grassland grasshoppers, however it is not enough to prevent the growth and coverage of native E. crassipes floating meadows because abundance of grasshoppers are realtively low and the growth rate and productivity of the host plant is high. Rev. Biol. Trop. 59 (3: 1407-1418. Epub 2011 September 01.Cornops aquaticum es una tucura semiacuática Neotropical que vive asociada a las Pontederiaceae y constituye uno de los más importantes herbívoros de

  7. The role of environment and core-margin effects on range-wide phenotypic variation in a montane grasshopper.

    Science.gov (United States)

    Noguerales, V; García-Navas, V; Cordero, P J; Ortego, J

    2016-11-01

    The integration of genetic information with ecological and phenotypic data constitutes an effective approach to gain insight into the mechanisms determining interpopulation variability and the evolutionary processes underlying local adaptation and incipient speciation. Here, we use the Pyrenean Morales grasshopper (Chorthippus saulcyi moralesi) as study system to (i) analyse the relative role of genetic drift and selection in range-wide patterns of phenotypic differentiation and (ii) identify the potential selective agents (environment, elevation) responsible for variation. We also test the hypothesis that (iii) the development of dispersal-related traits is associated with different parameters related to population persistence/turnover, including habitat suitability stability over the last 120 000 years, distance to the species distribution core and population genetic variability. Our results indicate that selection shaped phenotypic differentiation across all the studied morphological traits (body size, forewing length and shape). Subsequent analyses revealed that among-population differentiation in forewing length was significantly explained by a temperature gradient, suggesting an adaptive response to thermoregulation or flight performance under contrasting temperature regimes. We found support for our hypothesis predicting a positive association between the distance to the species distribution core and the development of dispersal-related morphology, which suggests an increased dispersal capability in populations located at range edges that, in turn, exhibit lower levels of genetic variability. Overall, our results indicate that range-wide patterns of phenotypic variation are partially explained by adaptation in response to local environmental conditions and differences in habitat persistence between core and peripheral populations. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary

  8. Combining RNA-seq and proteomic profiling to identify seminal fluid proteins in the migratory grasshopper Melanoplus sanguinipes (F).

    Science.gov (United States)

    Bonilla, Martha L; Todd, Christopher; Erlandson, Martin; Andres, Jose

    2015-12-22

    Seminal fluid proteins control many aspects of fertilization and in turn, they play a key role in post-mating sexual selection and possibly reproductive isolation. Because effective proteome profiling relies on the availability of high-quality DNA reference databases, our knowledge of these proteins is still largely limited to model organisms with ample genetic resources. New advances in sequencing technology allow for the rapid characterization of transcriptomes at low cost. By combining high throughput RNA-seq and shotgun proteomic profiling, we have characterized the seminal fluid proteins secreted by the primary male accessory gland of the migratory grasshopper (Melanoplus sanguinipes), one of the main agricultural pests in central North America. Using RNA sequencing, we characterized the transcripts of ~ 8,100 genes expressed in the long hyaline tubules (LHT) of the accessory glands. Proteomic profiling identified 353 proteins expressed in the long hyaline tubules (LHT). Of special interest are seminal fluid proteins (SFPs), such as EJAC-SP, ACE and prostaglandin synthetases, which are known to regulate female oviposition in insects. Our study provides new insights into the proteomic components of male ejaculate in Orthopterans, and highlights several important patterns. First, the presence of proteins that lack predicted classical secretory tags in accessory gland proteomes is common in male accessory glands. Second, the products of a few highly expressed genes dominate the accessory gland secretions. Third, accessory gland transcriptomes are enriched for novel transcripts. Fourth, there is conservation of SFPs' functional classes across distantly related taxonomic groups with very different life histories, mating systems and sperm transferring mechanisms. The identified SFPs may serve as targets of future efforts to develop species- specific genetic control strategies.

  9. The B chromosome polymorphism of the grasshopper Eyprepocnemis plorans in North Africa. IV. Transmission of rare B chromosome variants.

    Science.gov (United States)

    Bakkali, M; Camacho, J P M

    2004-01-01

    In addition to the principal B chromosome (B(1)) in Moroccan populations of the grasshopper Eyprepocnemis plorans, nine B chromosome variants appeared at low frequency. The transmission of five of these rare B chromosome variants through females was analysed in three natural populations. Sixteen controlled crosses provided useful information on the transmission of B(M2), B(M6) and B(M7) in Smir, B(M3) and B(M6) in SO.DE.A. (Société de Développement Agricole lands near Ksar-el-Kebir city), and B(M2) and B(M10) in Mechra, all located in Morocco. Since six female parents carried two different B variants, a total of 22 progeny analyses could be studied. Intraindividual variation in B transmission rate (k(B)) was observed among the successive egg pods in 26.7 % of the females, but this variation did not show a consistent temporal pattern. Only the B(M2) and B(M6) variants in Smir showed net drive, although variation was high among crosses, especially for B(M2). These two variants are thus good candidates for future regenerations (the replacement of a neutralized B, B(1) in this case, by a new driving variant, B(M2) or B(M6)) in Smir, the northern population where the B polymorphism is presumably older. The analysis of all crosses performed in the three populations, including those reported previously for the analysis of B(1) transmission, showed that the largest variance in k(B) among crosses stands at the individual level, and not at population or type of B levels. The implications of these findings for the occurrence of possible regeneration processes in Moroccan populations are discussed. Copyright 2004 S. Karger AG, Basel

  10. Ocean acidification affects parameters of immune response and extracellular pH in tropical sea urchins Lytechinus variegatus and Echinometra luccunter.

    Science.gov (United States)

    Leite Figueiredo, Débora Alvares; Branco, Paola Cristina; Dos Santos, Douglas Amaral; Emerenciano, Andrews Krupinski; Iunes, Renata Stecca; Shimada Borges, João Carlos; Machado Cunha da Silva, José Roberto

    2016-11-01

    The rising concentration of atmospheric CO 2 by anthropogenic activities is changing the chemistry of the oceans, resulting in a decreased pH. Several studies have shown that the decrease in pH can affect calcification rates and reproduction of marine invertebrates, but little attention has been drawn to their immune response. Thus this study evaluated in two adult tropical sea urchin species, Lytechinus variegatus and Echinometra lucunter, the effects of ocean acidification over a period of 24h and 5days, on parameters of the immune response, the extracellular acid base balance, and the ability to recover these parameters. For this reason, the phagocytic capacity (PC), the phagocytic index (PI), the capacity of cell adhesion, cell spreading, cell spreading area of phagocytic amebocytes in vitro, and the coelomic fluid pH were analyzed in animals exposed to a pH of 8.0 (control group), 7.6 and 7.3. Experimental pH's were predicted by IPCC for the future of the two species. Furthermore, a recovery test was conducted to verify whether animals have the ability to restore these physiological parameters after being re-exposed to control conditions. Both species presented a significant decrease in PC, in the pH of coelomic fluid and in the cell spreading area. Besides that, Echinometra lucunter showed a significant decrease in cell spreading and significant differences in coelomocyte proportions. The recovery test showed that the PC of both species increased, also being below the control values. Even so, they were still significantly higher than those exposed to acidified seawater, indicating that with the re-establishment of the pH value the phagocytic capacity of cells tends to restore control conditions. These results demonstrate that the immune system and the coelomic fluid pH of these animals can be affected by ocean acidification. However, the effects of a short-term exposure can be reversible if the natural values ​​are re-established. Thus, the effects of

  11. The effect of a diet containing grasshoppers and access to free-range on carcase and meat physicochemical and sensory characteristics in broilers.

    Science.gov (United States)

    Sun, T; Long, R J; Liu, Z Y

    2013-01-01

    1. Research was conducted to evaluate the impact of a diet containing grasshoppers on the carcase, physicochemical and sensory characteristics in a free-range, grassland-based broiler production system. 2. A total of 80, 28-d-old male broilers were reared on grassland containing a large population of grasshoppers (treatment PB). Control birds were reared intensively on a maize-soybean diet (treatment CB). At 91 d of age, 24 birds from each treatment were slaughtered to evaluate carcase, meat and sensory characteristics. 3. Treatment PB produced birds with significantly lower live weights, breast, wing, thigh and drum weights, and higher dressing percentage and breast percentage of carcase, compared with CB. Treatment PB produced breast meat with significantly higher redness values, shear force and protein content, and lower pH values, cooking loss, moisture and fat content compared with CB. Sensory panel results for breast and thigh meats showed no treatment effect on colour and juiciness, but significantly higher scores for chewiness, flavour, aroma and overall appreciation, and lower scores for tenderness from treatment PB compared with CB. 4. Rearing chickens on rangeland may provide an alternative way to produce poultry meat which is considered superior by modern consumers.

  12. Chromosomal Mapping of Repetitive DNAs in the Grasshopper Abracris flavolineata Reveal Possible Ancestry of the B Chromosome and H3 Histone Spreading

    Science.gov (United States)

    Bueno, Danilo; Palacios-Gimenez, Octavio Manuel; Cabral-de-Mello, Diogo Cavalcanti

    2013-01-01

    Supernumerary chromosomes (B chromosomes) occur in approximately 15% of eukaryote species. Although these chromosomes have been extensively studied, knowledge concerning their specific molecular composition is lacking in most cases. The accumulation of repetitive DNAs is one remarkable characteristic of B chromosomes, and the occurrence of distinct types of multigene families, satellite DNAs and some transposable elements have been reported. Here, we describe the organization of repetitive DNAs in the A complement and B chromosome system in the grasshopper species Abracris flavolineata using classical cytogenetic techniques and FISH analysis using probes for five multigene families, telomeric repeats and repetitive C0t-1 DNA fractions. The 18S rRNA and H3 histone multigene families are highly variable and well distributed in A. flavolineata chromosomes, which contrasts with the conservation of U snRNA genes and less variable distribution of 5S rDNA sequences. The H3 histone gene was an extensively distributed with clusters occurring in all chromosomes. Repetitive DNAs were concentrated in C-positive regions, including the pericentromeric region and small chromosomal arms, with some occurrence in C-negative regions, but abundance was low in the B chromosome. Finally, the first demonstration of the U2 snRNA gene in B chromosomes in A. flavolineata may shed light on its possible origin. These results provide new information regarding chromosomal variability for repetitive DNAs in grasshoppers and the specific molecular composition of B chromosomes. PMID:23826099

  13. Microsatellite organization in the grasshopper Abracris flavolineata (Orthoptera: Acrididae revealed by FISH mapping: remarkable spreading in the A and B chromosomes.

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    Diogo Milani

    Full Text Available With the aim of acquiring deeper knowledge about repetitive DNAs chromosomal organization in grasshoppers, we used fluorescent in situ hybridization (FISH to map the distribution of 16 microsatellite repeats, including mono-, di-, tri- and tetra-nucleotides, in the chromosomes of the species Abracris flavolineata (Acrididae, which harbors B chromosome. FISH revealed two main patterns: (i exclusively scattered signals, and (ii scattered and specific signals, forming evident blocks. The enrichment was observed in both euchromatic and heterochromatic areas and only the motif (C30 was absent in heterochromatin. The A and B chromosomes were enriched with all the elements that were mapped, being observed in the B chromosome more distinctive blocks for (GA15 and (GAG10. For A complement distinctive blocks were noticed for (A30, (CA15, (CG15, (GA15, (CAC10, (CAA10, (CGG10, (GAA10, (GAC10 and (GATA8. These results revealed an intense spreading of microsatellites in the A. flavolineata genome that was independent of the A+T or G+C enrichment in the repeats. The data indicate that the microsatellites compose the B chromosome and could be involved in the evolution of this element in this species, although no specific relationship with any A chromosome was observed to discuss about its origin. The systematic analysis presented here contributes to the knowledge of repetitive DNA chromosomal organization among grasshoppers including the B chromosomes.

  14. Field Insect Pests and Crop Damage Assessment of Pigeon Pea (Cajanus cajan [L.] Huth grown under Ratoon and in Mixture with Maize Evaluación de Campo de Insectos Pestes y Daño del cultivo de Gandul (Cajanus cajan [L.] Huth creciendo bajo Rebrotes o en Mezcla con Maíz

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    Madang A Dasbak

    2012-03-01

    Full Text Available The widespread adoption of cropping systems that are sustainable and environmentally friendly is vital for the macroeconomic survival of civilization. Intercropping could ensure stability of insect populations in a system. A 3-yr (2005-2007 field trial was therefore carried out in Nigeria under regular and ratoon crops to evaluate five recently developed pigeon pea (Cajanus cajan [L.] Huth genotypes (ICPL 87, ICPL 161, ICPL 85063, ICP 7120, and ICPL 87119 from the International Crops Research Institute for Semi-Arid Tropics (ICRISAT and one local variety for their relative performance and susceptibility to insect pests. The pigeon pea genotypes were in a mixture with two maize genotypes (Zea mays L., open-pollinated and hybrid in regular crops for 2 yr (2005-2006 followed by a ratoon crop for 1 yr (2007. Termites (Odontotermes badius, crickets (Gymnogryllus lucens, and variegated grasshoppers (Zonocerus variegatus were the crop's seedling pests and caused minimal damage. Clavigralla spp. infestations were high at the reproductive stage causing 24% and 29% seed damage in regular and ratoon pigeon pea crops, respectively. Maize slightly suppressed insect pest incidence and damage to pigeon pea pods and seeds but significantly (P La extendida adopción de sistemas de cultivo que son sustentables y benignos para el medio ambiente es vital para la supervivencia macro-económica de la civilización. El intercultivo podría asegurar la estabilidad de población de insectos en un sistema. Un ensayo de campo de 3 anos (2005-2007 fue realizado en Nigeria bajo condiciones de cultivo regular y ratoon para evaluar cinco genotipos de poroto gandul (Cajanus cajan [L.] Huth: ICPL 87, ICPL 161, ICPL 85063, ICP 7120, e ICPL 87119 desde International Crops Research Institute for Semi-Arid Tropics (ICRISAT y una variedad local, por sus rendimientos y susceptibilidades relativas a insectos plaga. Los genotipos de poroto gandul estaban en mezcla con dos genotipos de

  15. Effects of Abiotic Factors on the Geographic Distribution of Body Size Variation and Chromosomal Polymorphisms in Two Neotropical Grasshopper Species (Dichroplus: Melanoplinae: Acrididae

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    Claudio J. Bidau

    2012-01-01

    Full Text Available We review the effects of abiotic factors on body size in two grasshopper species with large geographical distributions: Dichroplus pratensis and D. vittatus, inhabiting Argentina in diverse natural habitats. Geographical spans for both species provide an opportunity to study the effects of changes in abiotic factors on body size. The analyses of body size distribution in both species revealed a converse Bergmannian pattern: body size is positively correlated with latitude, altitude, and seasonality that influences time available for development and growth. Allen’s rule is also inverted. Morphological variability increases towards the ends of the Bergmannian clines and, in D. pratensis, is related with a central-marginal distribution of chromosomal variants that influence recombination. The converse Bergmannian patterns influence sexual size dimorphism in both species but in different fashions. Body size variation at a microspatial scale in D. pratensis is extremely sensitive to microclimatic clines. We finally compare our results with those for other Orthopteran species.

  16. Object-Based Classification as an Alternative Approach to the Traditional Pixel-Based Classification to Identify Potential Habitat of the Grasshopper Sparrow

    Science.gov (United States)

    Jobin, Benoît; Labrecque, Sandra; Grenier, Marcelle; Falardeau, Gilles

    2008-01-01

    The traditional method of identifying wildlife habitat distribution over large regions consists of pixel-based classification of satellite images into a suite of habitat classes used to select suitable habitat patches. Object-based classification is a new method that can achieve the same objective based on the segmentation of spectral bands of the image creating homogeneous polygons with regard to spatial or spectral characteristics. The segmentation algorithm does not solely rely on the single pixel value, but also on shape, texture, and pixel spatial continuity. The object-based classification is a knowledge base process where an interpretation key is developed using ground control points and objects are assigned to specific classes according to threshold values of determined spectral and/or spatial attributes. We developed a model using the eCognition software to identify suitable habitats for the Grasshopper Sparrow, a rare and declining species found in southwestern Québec. The model was developed in a region with known breeding sites and applied on other images covering adjacent regions where potential breeding habitats may be present. We were successful in locating potential habitats in areas where dairy farming prevailed but failed in an adjacent region covered by a distinct Landsat scene and dominated by annual crops. We discuss the added value of this method, such as the possibility to use the contextual information associated to objects and the ability to eliminate unsuitable areas in the segmentation and land cover classification processes, as well as technical and logistical constraints. A series of recommendations on the use of this method and on conservation issues of Grasshopper Sparrow habitat is also provided.

  17. Uncovering the evolutionary history of neo-XY sex chromosomes in the grasshopper Ronderosia bergii (Orthoptera, Melanoplinae) through satellite DNA analysis.

    Science.gov (United States)

    Palacios-Gimenez, Octavio M; Milani, Diogo; Lemos, Bernardo; Castillo, Elio R; Martí, Dardo A; Ramos, Erica; Martins, Cesar; Cabral-de-Mello, Diogo C

    2018-01-08

    Neo-sex chromosome systems arose independently multiple times in evolution, presenting the remarkable characteristic of repetitive DNAs accumulation. Among grasshoppers, occurrence of neo-XY was repeatedly noticed in Melanoplinae. Here we analyzed the most abundant tandem repeats of R. bergii (2n = 22, neo-XY♂) using deep Illumina sequencing and graph-based clustering in order to address the neo-sex chromosomes evolution. The analyses revealed ten families of satDNAs comprising about ~1% of the male genome, which occupied mainly C-positive regions of autosomes. Regarding the sex chromosomes, satDNAs were recorded within centromeric or interstitial regions of the neo-X chromosome and four satDNAs occurred in the neo-Y, two of them being exclusive (Rber248 and Rber299). Using a combination of probes we uncovered five well-defined cytological variants for neo-Y, originated by multiple paracentric inversions and satDNA amplification, besides fragmented neo-Y. These neo-Y variants were distinct in frequency between embryos and adult males. The genomic data together with cytogenetic mapping enabled us to better understand the neo-sex chromosome dynamics in grasshoppers, reinforcing differentiation of neo-X and neo-Y and revealing the occurrence of multiple additional rearrangements involved in the neo-Y evolution of R. bergii. We discussed the possible causes that led to differences in frequency for the neo-Y variants between embryos and adults. Finally we hypothesize about the role of DNA satellites in R. bergii as well as putative historical events involved in the evolution of the R. bergii neo-XY.

  18. Monograph of the Afrotropical species of Scelio Latreille (Hymenoptera, Platygastridae), egg parasitoids of acridid grasshoppers (Orthoptera, Acrididae).

    Science.gov (United States)

    Yoder, Matthew J; Valerio, Alejandro A; Polaszek, Andrew; van Noort, Simon; Masner, Lubomír; Johnson, Norman F

    2014-01-01

    The genus Scelio is a cosmopolitan and speciose group of solitary parasitoids of the eggs of short-horned grasshoppers (Orthoptera: Acrididae). A number of these hosts are important pests, including plague locusts of the genus Schistocerca. Species of Scelio are recognized as potentially important biological control agents, but this possibility has yet to be fully realized, in part because the species-level taxonomy is still incompletely developed. The species of the pulchripennis group have been recently revised. As a continuation of this effort, here we revise the Afrotropical species of Scelio, excluding the pulchripennis species group. Sixty two (62) species are treated, 48 of which are new. Species are classified into the following species groups: ernstii (12 species, 9 new), howardi (23 species, 19 new), ipomeae (6 species, 5 new), irwini (4 species, 3 new), simoni (3 new species) and walkeri (12 species, 9 new). Keys to species groups and to the species within each group are provided. New species described are: S. albatus Yoder, sp. n., S. aphares Yoder, sp. n., S. apospastos Yoder, sp. n., S. ardelio Yoder, sp. n., S. aurantium Yoder, sp. n., S. balo Valerio & Yoder, sp. n., S. bayanga Yoder, sp. n., S. bubulo Yoder, sp. n., S. cano Yoder, sp. n., S. clypeatus Yoder, sp. n., S. concavus Yoder, sp. n., S. copelandi Yoder, sp. n., S. crepo Yoder, sp. n., S. destico Yoder, sp. n., S. dupondi Yoder, sp. n., S. effervesco Yoder, sp. n., S. erugatus Yoder, sp. n., S. exophthalmus Yoder, sp. n., S. fremo Valerio & Yoder, sp. n., S. gemo Yoder, sp. n., S. grunnio Yoder, sp. n., S. harinhalai Yoder, sp. n., S. igland Yoder, sp. n., S. impostor Yoder, sp. n., S. irwini Yoder, sp. n., S. janseni Yoder, sp. n., S. latro Yoder, sp. n., S. memorabilis Yoder, sp. n., S. modulus Yoder, sp. n., S. mutio Yoder, sp. n., S. ntchisii Yoder, sp. n., S. parkeri Yoder, sp. n., S. phaeoprora Yoder, sp. n., S. pilosilatus Yoder, sp. n., S. pipilo Yoder, sp. n., S. quasiclypeatus

  19. Diversidad y distribución de acridios (Orthoptera: Acridoidea en pastizales del sur de la región pampeana, Argentina Diversity and distribution of grasshoppers (Orthoptera: Acridoidea in grasslands of the Southern Pampas region, Argentina

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    Yanina Mariottini

    2013-03-01

    Full Text Available Los acridios son componentes nativos de los pastizales, dichos sistemas han sido modificados debido a la intensificación de las actividades agrícola-ganaderas y por lo tanto se considera importante estudiar las comunidades de acridios asociadas. Se estudió la diversidad y distribución de acridios en el Sur de la región pampeana a través de muestreos realizados en las comunidades vegetales más representativas del partido de Laprida, provincia de Buenos Aires, durante cinco temporadas (2005-2010. Se recolectaron 22 especies. La subfamilia Melanoplinae fue la más diversa (ocho especies. La mayor cantidad de especies se observó en los pastizales nativos (18. La diversidad en los pastizales alterados (1.75±0.096 fue superior (pIn Argentina, the grasslands of Pampas region comprise approximately 15% of the country. As in other grasslands of the world, grasshoppers are among the most important native herbivores. Their economic importance has been recognized in Argentina since the mid to late nineteenth century, since outbreaks of different species have become recurrent phenomena. Therefore, the main objective of this work was to study their diversity and distribution in grasslands of the Southern Pampas region (Laprida county, Buenos Aires province, as one of the most affected areas. The study was conducted during five seasons (2005-10. Sampling sites were represented by the most common plant communities in this area, classified in four categories: native grasslands, disturbed grasslands, implanted pastures and halophilous grasslands. The samplings were conducted from mid-spring to early autumn, with five or six samples per season. We estimated the following population descriptors: species richness (S, eveness (E, dominance (J, and diversity index (H´. In order to evaluate the similitude of the grasshopper communities present in the different plant communities, we used qualitative and quantitative coefficients of similitude. A total of 22

  20. Molecular Cloning and mRNA Expression of Heat Shock Protein Genes and Their Response to Cadmium Stress in the Grasshopper Oxya chinensis.

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    Yuping Zhang

    Full Text Available Heat shock proteins (Hsps are highly conserved molecular chaperones that are synthesized in response to stress. In this study, we cloned the full-length sequences of the Grp78 (glucose-regulated protein 78, Hsp70, Hsp90, and Hsp40 genes from the Chinese rice grasshopper Oxya chinensis. The full-length cDNA sequences of OcGrp78, OcHsp70, OcHsp90, and OcHsp40 contain open reading frames of 1947, 1920, 2172, and 1042 bp that encode proteins of 649, 640, 724, and 347 amino acids, respectively. Fluorescent real-time quantitative PCR (RT-qPCR was performed to quantify the relative transcript levels of these Hsp genes in different tissues and developmental stages. The mRNAs encoding these four Hsp genes were present at all developmental stages and in all tissues examined but were expressed at varying levels. Additionally, we investigated the mRNA expression profiles of these four Hsps in O. chinensis subjected to Cadmium (Cd stress. OcGrp78, OcHsp70, OcHsp90, and OcHsp40 mRNA expression was induced under acute Cd stress; the levels reached a maximum within a short time (6 h, were reduced significantly at 12 h, and were lowered to or below control levels by 48 h. Regarding induction efficiency, OcHsp70 was the most sensitive gene to acute Cd stress. Chronic Cd exposure showed that dietary Cd treatment induced increased OcGrp78, OcHsp90, and OcHsp40 expression. However, dietary Cd induced a significant reduction of OcHsp70 expression. In the period tested, no significant difference in the mortality of the grasshoppers was observed. Our results suggest that these four Hsps genes, especially OcHsp70, are sensitive to acute Cd stress and could be used as molecular markers for toxicology studies. However, our results also indicate that OcHsp70 is not suitable for use as a molecular marker of chronic Cd contamination.

  1. Molecular Cloning and mRNA Expression of Heat Shock Protein Genes and Their Response to Cadmium Stress in the Grasshopper Oxya chinensis.

    Science.gov (United States)

    Zhang, Yuping; Liu, Yaoming; Zhang, Jianzhen; Guo, Yaping; Ma, Enbo

    2015-01-01

    Heat shock proteins (Hsps) are highly conserved molecular chaperones that are synthesized in response to stress. In this study, we cloned the full-length sequences of the Grp78 (glucose-regulated protein 78), Hsp70, Hsp90, and Hsp40 genes from the Chinese rice grasshopper Oxya chinensis. The full-length cDNA sequences of OcGrp78, OcHsp70, OcHsp90, and OcHsp40 contain open reading frames of 1947, 1920, 2172, and 1042 bp that encode proteins of 649, 640, 724, and 347 amino acids, respectively. Fluorescent real-time quantitative PCR (RT-qPCR) was performed to quantify the relative transcript levels of these Hsp genes in different tissues and developmental stages. The mRNAs encoding these four Hsp genes were present at all developmental stages and in all tissues examined but were expressed at varying levels. Additionally, we investigated the mRNA expression profiles of these four Hsps in O. chinensis subjected to Cadmium (Cd) stress. OcGrp78, OcHsp70, OcHsp90, and OcHsp40 mRNA expression was induced under acute Cd stress; the levels reached a maximum within a short time (6 h), were reduced significantly at 12 h, and were lowered to or below control levels by 48 h. Regarding induction efficiency, OcHsp70 was the most sensitive gene to acute Cd stress. Chronic Cd exposure showed that dietary Cd treatment induced increased OcGrp78, OcHsp90, and OcHsp40 expression. However, dietary Cd induced a significant reduction of OcHsp70 expression. In the period tested, no significant difference in the mortality of the grasshoppers was observed. Our results suggest that these four Hsps genes, especially OcHsp70, are sensitive to acute Cd stress and could be used as molecular markers for toxicology studies. However, our results also indicate that OcHsp70 is not suitable for use as a molecular marker of chronic Cd contamination.

  2. Induction of gene expression in sheepshead minnows (Cyprinodon variegatus) treated with 17beta-estradiol, diethylstilbestrol, or ethinylestradiol: the use of mRNA fingerprints as an indicator of gene regulation.

    Science.gov (United States)

    Denslow, N D; Bowman, C J; Ferguson, R J; Lee, H S; Hemmer, M J; Folmar, L C

    2001-03-01

    The recent interest in hormonally active environmental contaminants has sparked a drive to find sensitive methods to measure their effects on wildlife. A molecular-based assay has been developed to measure the induction of gene expression in sheepshead minnows (Cyprinodon variegatus) exposed in vivo to the natural and pharmaceutical estrogens 17beta-estradiol, ethinylestradiol, and diethylstilbestrol. This method used differential display reverse transcriptase polymerase chain reaction assays to compare the expression of individual mRNAs from control and estrogen-exposed fish. Forty-eight differentially expressed cDNAs were isolated by this method, including cDNAs for vitelline envelope proteins and vitellogenin. The mRNA expression patterns for fish injected with a pharmacological dose of estradiol (5 mg/kg) were identical to those obtained in fish receiving constant aqueous exposure to 212 ng estradiol/liter. Further, the cDNA "fingerprint" pattern observed in the estradiol-treated fish also matched that obtained in fish receiving continuous-flow aqueous exposures to 192 ng ethinyl estradiol/liter and a nominal concentration of 200 ng diethylstilbestrol/liter. The results demonstrate a characteristic expression pattern for genes upregulated by exposure to a variety of natural and anthropogenic estrogens and suggest this approach may be valuable to examine the potential effects of environmental contaminants on other endocrine-mediated pathways of reproduction, growth, and development. Copyright 2001 Academic Press.

  3. The U2 snDNA Is a Useful Marker for B Chromosome Detection and Frequency Estimation in the Grasshopper Abracris flavolineata.

    Science.gov (United States)

    Milani, Diogo; Palacios-Gimenez, Octavio M; Cabral-de-Mello, Diogo C

    2017-01-01

    In this study, we describe a strategy to determine the presence of B chromosomes in the living grasshopper Abracris flavolineata by FISH using U2 snDNA as a probe in interphase hemolymph nuclei. In individuals without B chromosomes, (0B) 2 dot signals were noticed, corresponding to A complement U2 snDNA clusters. In +1B and +2B individuals, 4 or 8 additional signals were noticed, respectively. In all cases, the absence or presence of 1 or 2 B chromosomes correlated in hemolymph and in somatic or germline tissues, validating the efficiency of the marker. Our data suggest that the B chromosome of A. flavolineata is present in all somatic tissues. B-carrying individuals showed the same number of B chromosomes in germ and somatic cells, suggesting that the B is mitotically stable. The marker was used to compare B chromosome frequency in the analyzed population with a sample collected previously, in order to test for B frequency changes and differences of B chromosome prevalence among sexes, but no statistically significant differences were noticed. The identification of living animals harboring B chromosomes will be very useful in future studies of B chromosome transmission, as well as in functional studies involving RNA analysis, thus contributing to the understanding of evolutionary history and the possible role of the B chromosome in A. flavolineata. © 2017 S. Karger AG, Basel.

  4. Biomonitoring of the genotoxic effects and oxidative potentials of commercial edible dung beetles (Onitis sp.), grasshopper (Caelifera sp.) and mole crickets (Gryllotalpa sp.) in vitro.

    Science.gov (United States)

    Koc, Kubra; Incekara, Umit; Turkez, Hasan

    2014-09-01

    In this investigation, the genotoxic and oxidative effects of water soluble extracts of dung beetles, flying grasshopper and mole crickets have been assessed on cultured human blood cells. The extracts were added to the culture tubes at 12 different concentrations (0-2000 ppm). Micronucleus test was used to monitor the DNA and the chromosomal damage produced by aqueous extracts in vitro. In addition, to assess the oxidative effects, total antioxidant capacity (TAC) and total oxidant status (TOS) levels were also measured. Our results indicated that these extracts did not show genotoxic effects at the tested concentrations. However, the extracts caused dose-dependent alterations in both TAC and TOS levels. Based on the findings, it was concluded that the studied insects can be consumed safely, but it is necessary to consider the cellular damages which are likely to appear depending on oxidative stress at higher concentrations. It has also been suggested that this in vitro approach for oxidative and genotoxicity assessments may be useful to evaluate the potential health risks of edible insects. © The Author(s) 2014.

  5. Flutuação populacional de gafanhotos na Floresta Nacional de Chapecó, Santa Catarina Grasshopper Population fluctuation in the National Forest of Chapeco, Santa Catarina

    Directory of Open Access Journals (Sweden)

    Cladis Juliana Lutinski

    2009-04-01

    Full Text Available Com o objetivo de verificar a flutuação populacional de gafanhotos na Floresta Nacional de Chapecó (FLONA, em Santa Catarina, foram realizadas coletas semanais durante o período de dezembro de 2003 a dezembro de 2004 com armadilhas do tipo pit-fall, rede de varredura, guarda-chuva entomológico e malaise. Os picos populacionais para a maioria das espécies ocorreram durante os meses de dezembro, janeiro e fevereiro. A análise de regressão (5% apontou relação significativa entre os fatores climáticos e os níveis populacionais de Allotruxalis gracilis (Giglio-Tos, 1897, Parorphula graminea Bruner, 1900, Rhammatocerus brunneri (Giglio – Tos, 1895 e Xyleus discoideus discoideus (Serville, 1831.In order to verify the grasshopper population dynamics in the National Forest of Chapecó, SC., weekly collections were made between December 2003 and December 2004, using pit-fall traps, sweep nets, entomological umbrellas and malaises traps. The population peaks for most of the species was reached in December, January and February. The regression analysis (5% showed significant relation between the climatic factors and the population levels of Allotruxalis gracilis (Giglio-Tos, 1897, Parorphula graminea Bruner, 1900, Rhammatocerus brunneri (Giglio – Tos, 1895 and Xyleus discoideus discoideus (Serville, 1831.

  6. Unraveling the diversification history of grasshoppers belonging to the “Trimerotropis pallidipennis” (Oedipodinae: Acrididae species group: a hotspot of biodiversity in the Central Andes

    Directory of Open Access Journals (Sweden)

    Noelia Verónica Guzmán

    2017-09-01

    Full Text Available The Andean Mountain range has been recognized as one of the biodiversity hotspots of the world. The proposed mechanisms for such species diversification, among others, are due to the elevation processes occurring during the Miocene and the intensive glacial action during the Pleistocene. In this study we investigated the diversification history of the grasshopper Trimerotropis pallidipennis species complex which shows a particularly wide latitudinal and altitudinal distribution range across the northern, central and southern Andes in South America. Many genetic lineages of this complex have been so far discovered, making it an excellent model to investigate the role of the central Andes Mountains together with climatic fluctuations as drivers of speciation. Phylogenetics, biogeographic and molecular clock analyses using a multi-locus dataset revealed that in Peru there are at least two, and possibly four genetic lineages. Two different stocks originated from a common ancestor from North/Central America—would have dispersed toward southern latitudes favored by the closure of the Panama Isthmus giving rise to two lineages, the coastal and mountain lineages, which still coexist in Peru (i.e., T. pallidipennis and T. andeana. Subsequent vicariant and dispersal events continued the differentiation process, giving rise to three to six genetic lineages (i.e., clades detected in this study, which were geographically restricted to locations dispersed over the central Andes Mountains in South America. Our results provide another interesting example of “island diversification” motored by the topography plus unstable climatic conditions during the Pleistocene, pointing out the presence of a hotspot of diversification in the Andean region of Peru.

  7. Polymorphism of the grasshopper Rhammatocerus schistocercoides populations revealed by RAPD Polimorfismo em populações do gafanhoto Rhammatocerus schistocercoides revelado por marcadores RAPD

    Directory of Open Access Journals (Sweden)

    João Batista Tavares da Silva

    2002-11-01

    Full Text Available The objective of this work was to study the genetic variability of the grasshopper Rhammatocerus schistocercoides (Orthoptera: Acrididae using RAPD analysis among individuals from three populations, one from Colombia and two from Brazil (Goiás and Mato Grosso States. Ninety scorable binary markers were obtained by fingerprinting with 11 oligonucleotide primers. Most of the polymorphism was attributed to 42 markers with variable frequency among the different populations. Although the existence of significant difference among populations (PO objetivo deste trabalho foi estudar a variabilidade genética do gafanhoto Rhammatocerus schistocercoides (Orthoptera: Acrididae por meio da análise de RAPD entre indivíduos de três populações, uma da Colômbia e duas do Brasil (Goiás e Mato Grosso. Noventa marcadores binários foram selecionados através de análise de polimorfismo com o uso de 11 oligonucleotídeos. A maior parte do polimorfismo observado foi atribuída a 42 marcadores com freqüência variável entre as diferentes populações. Apesar da existência de diferença significativa interpopulacional (P<0,0001, grande proporção da variabilidade genética foi detectada dentro das populações (87,7% da variação total. As distâncias entre as populações colombianas e brasileiras foram 0,12 (P<0,0001 e 0,18 (P<0,0001 para Goiás e Mato Grosso, respectivamente. A distância obtida entre Goiás e Mato Grosso foi 0,06 (P<0,0001. Estes dados indicam que as diferenças fenotípicas entre populações estão associadas principalmente às distâncias geográficas entre as populações do Brasil e a da Colômbia.

  8. Gafanhotos (Orthoptera, Acridoidea em áreas de cerrados e lavouras na Chapada dos Parecis, Estado de Mato Grosso, Brasil Grasshoppers (Orthoptera, Acridoidea in native savanna and crop areas in Chapada dos Parecis, Mato Grosso State, Brazil

    Directory of Open Access Journals (Sweden)

    Wanderlei Dias Guerra

    2012-06-01

    Full Text Available Gafanhotos (Orthoptera, Acridoidea em áreas de cerrados e lavouras na Chapada dos Parecis, Estado de Mato Grosso, Brasil. Foi determinada a composição e abundância de espécies de gafanhotos usando amostragem com rede entomológica durante 3 anos de estudo na Chapada dos Parecis, estado de Mato Grosso. O levantamento foi feito em áreas de lavouras e com vegetação ainda nativa (cerrados com, respectivamente, 56 e 59 locais inventariados em cada ambiente. Foram coletados 3.031 indivíduos de gafanhotos de 64 espécies distribuídas entre as famílias e subfamílias: Acrididae (49: Gomphocerinae (21, Ommatolampinae (10, Melanoplinae (6, Acridinae (4 Leptysminae (3, Copiocerinae (3, Proctolabinae (1 e Cyrtacanthacridinae (1; Romaleidae (1: Romaleinae (13 e Ommexechidae (1: Ommexechinae (2, além de 1550 ninfas. A diversidade de espécies foi maior no cerrado (61 do que nas lavouras (16, ocorrendo o inverso com relação à abundância onde as espécies Baeacris punctulatus (Thunberg, 1824 e Orphulella punctata (De Geer, 1773 predominaram representando 49,5% do total de indivíduos coletados em toda a Chapada dos Parecis e, juntas, somam 78,8% da abundância registrada nas áreas de lavouras e tem potencial de se tornarem pragas.Grasshoppers (Orthoptera, Acridoidea in native savanna and crop areas in Chapada dos Parecis, Mato Grosso State, Brazil. We determined the composition and abundance of grasshoppers using sweep net sampling during three years at the Parecis Plateau, State of Mato Grosso, Brazil. The survey was done in areas with crops and native vegetation (savanna with, respectively, 56 and 59 sites available in each environment. 3.031 individuals of grasshoppers were collected from 64 species distributed among the following families and subfamilies: Acrididae (49: Gomphocerinae (21, Ommatolampinae (10, Melanoplinae (6, Acridinae (4 Leptysminae (3, Copiocerinae (3, Proctolabinae (1 and Cyrtacanthacridinae (1; Romaleidae (1: Romaleinae

  9. Nuevos registros de hongos entomopatógenos en acridios (Orthoptera: Acridoidea de la República Argentina New records of entomopathogenic fungi from grasshoppers (Orthoptera: Acridoidea in Argentina

    Directory of Open Access Journals (Sweden)

    Sebastian A. Pelizza

    2010-12-01

    Full Text Available Los acridios (tucuras y langostas continúan ocasionando pérdidas económicas en la agricultura a nivel mundial. En Argentina, la importancia de estos insectos ha sido reconocida desde mediados del siglo XIX, dependiendo de la región considerada y en relación al progresivo desarrollo agropecuario en el país. Los hongos son los microorganismos parásitos de insectos más frecuentemente encontrados en la naturaleza y la mayoría de las investigaciones con hongos entomopatógenos se ha centrado en su desarrollo como bioplaguicidas. En el presente trabajo se dan a conocer cinco registros nuevos de Beauveria bassiana (Bals.-Criv. Vuill., y dos de Entomophaga grylli (Fresen. A. Batko que se encontraron afectando distintas especies de acridios; se amplía así la distribución geográfica y el espectro hospedador para estas especies fúngicas. Cabe destacar que con el aporte de estos siete registros nuevos, el número total de hongos entomopatógenos de acridios citados para la República Argentina se eleva de 22 a 29.Grasshoppers and locusts continue causing serious economic losses in agriculture worldwide. In Argentina, the importance of these insects has been recognized since the mid-nineteenth century, depending on the region considered and in relation to the progressive development of agriculture. Fungi are the most frequently found microorganisms parasitizing insects in nature, and most of the entomopathogenic fungi investigations have been focused on their development as biopesticides. In this study five new records of Beauveria bassiana (Bals.-Criv. Vuill., and two new records of Entomophaga grylli (Fresen. A. Batko, are presented, extending the geographical distribution and the host range for these fungal species. With these seven new records, the total number of grasshopper entomopathogenic fungi cited for Argentina is raised from 22 to 29.

  10. Evaluation of toxicity to the amphipod, Hyalella azteca, and to the midge, Chironomus dilutus; and bioaccumulation by the oligochaete, Lumbriculus variegatus, with exposure to PCB-contaminated sediments from Anniston, Alabama

    Science.gov (United States)

    Ingersoll, Christopher G.; Steevens, Jeffery A.; MacDonald, Donald D.; Brumbaugh, William G.; Coady, Matthew R.; Farrar, J. Daniel; Lotufo, Guilherme R.; Kemble, Nile E.; Kunz, James L.; Stanley, Jacob K.; Sinclair, Jesse A.; Ingersoll, Christopher G.; Steevens, Jeffery A.; MacDonald, Donald D.

    2014-01-01

    The U.S. Environmental Protection Agency (USEPA) requested that as part of the remedial investigation for the Anniston, Alabama Polychlorinated Biphenyl (PCB) Site (Anniston PCB Site), that Pharmacia Corporation and Solutia Inc. (P/S) perform long-term reproduction toxicity tests with the amphipod, Hyalella azteca, and the midge, Chironomus dilutus, and bioaccumulation tests with the oligochaete, Lumbriculus variegatus, using sediment samples collected from reference locations and from Operable Unit 4 of the Anniston PCB Site. The sediment toxicity testing and sediment bioaccumulation results will be used by ARCADIS U.S., Inc. (ARCADIS) as part of a weight-of-evidence assessment to evaluate risks and establish sediment remediation goals for contaminants to sediment-dwelling organisms inhabiting the Anniston PCB Site. The goal of this study was to characterize relations between sediment chemistry and sediment toxicity and relations between sediment chemistry and sediment bioaccumulation in samples of sediments collected from the Anniston PCB Site. A total of 32 samples were evaluated from six test sites and one reference site to provide a wide range in concentrations of chemicals of potential concern (COPCs) including PCBs in samples of whole sediment. The goal of this study was not to determine the extent of sediment contamination across the Anniston PCB Site. Hence, the test sites or samples collected from within a test site were not selected to represent the spatial extent of sediment contamination across the Anniston PCB Site. Sediment chemistry, pore-water chemistry, and sediment toxicity data were generated for 26 sediment samples from the Anniston PCB Site. All of the samples were evaluated to determine if they qualified as reference sediment samples. Those samples that met the chemical selection criteria and biological selection criteria were identified as reference samples and used to develop the reference envelope for each toxicity test endpoint. Physical

  11. Grasshoppers – Generalists to Specialists?

    Indian Academy of Sciences (India)

    IAS Admin

    preference for a particular food, developed these for plants whose chemical defenses .... sure to the compound and thus can eat NHT-treated food, as readily as normal food ... plants and also using them for their own benefits. A constant tug.

  12. Grasshoppers (Orthoptera: Caelifera and crickets (Orthoptera: Ensifera from slopes of Macošská stráň and Vilémovická stráň (Moravský kras Protected landscape area, Czech Republic

    Directory of Open Access Journals (Sweden)

    Jana Niedobová

    2011-01-01

    Full Text Available In 2008 we found 21 species of grasshoppers and crickets on Macošská stráň slope and 18 species on Vilémovická stráň slope. Both slopes are located in the northern part of the Moravský kras Protected landscape area and have xerothermic character. Both slopes are influenced by pasture management. For the most comprehensive picture of Orthoptera we used a standard method (sweeping of vegetation and nonstandard methods (pitfall traps and Möricke yellow cups. Termophilous species of Orthoptera on Macošská stráň (47% were dominating. On Vilémovická stráň mezophilous species (46% were dominating. The most common species were Stenobothrus lineatus (Panzer, 1796 on Macošská stráň slope and Chorthippus parallelus (Zetterstedt, 1821, Stenobothrus lineatus, Chorthippus bigutulus (Linné, 1758 and Chorthippus dorsatus (Zetterstedt, 1821 on Vilémovická stráň slope. Rare species of this assemblage were Stenobothrus nigromaculatus (Herrich-Schaffer, 1840 which was on Macošská stráň slope only and Tetrix bipunctata (Linnaeus, 1758 which has much bigger abundances also on Macošská stráň slope.

  13. Sistemas de Información Geográfica y Teledetección en Entomología: Aplicación en tucuras y langostas (Orthoptera: Acridoidea Geographic Information Systems (GIS and remote sensing in Entomology: studies in grasshoppers and locusts (Orthoptera: Acridoidea

    Directory of Open Access Journals (Sweden)

    M. Marta Cigliano

    2003-07-01

    Full Text Available El desarrollo, relativamente reciente, de dos tecnologías de análisis de patrones espaciales, como son los Sistemas de Información Geográfica (SIG y la teledetección, ha abierto nuevos caminos en estudios sobre entomología aplicada. Los SIG han facilitado a entomólogos y ecólogos el análisis de aquellos patrones espaciales complejos que presentan una variación temporal. Tal vez uno de los principales usos de los SIG dentro de la entomología aplicada está vinculado con el estudio de las relaciones entre las explosiones poblacionales de insectos ("outbreaks" y las variables ambientales. Las explosiones poblacionales de acridios, tanto de especies de langostas como de tucuras, son ejemplos típicos de la dinámica espacial de insectos que ocurre a gran escala y que se ve afectada por condiciones locales que varían en el tiempo. Debido a estas características este grupo de insectos plaga ha sido objeto de análisis y aplicación de estas nuevas herramientas. En este trabajo se brindan los conceptos básicos de los SIG y la teledetección y se lleva a cabo una revisión de su utilidad en entomología aplicada, utilizando los estudios de su aplicación en acridios como ejemplo.The advent of Geographic Information Systems (GIS and remote sensing has made the analysis of complex spatial patterns an attainable reality for entomologists and ecologists. Within the general area of applied insect entomology, perhaps one of the major uses of GIS is the one that relates insect outbreaks to environmental features of the landscape. Outbreaks of grasshoppers and locusts are typical examples of large-scale spatial dynamics that are affected by local conditions that fluctuate with time. Factors affecting the numerical fluctuations in grasshopper and locust populations are usually variables that have both spatial and temporal characteristics and thus can be mapped and incorporated into a GIS. Following a brief introduction to GIS and remote sensing, a

  14. ¿La práctica de la siembra directa en cultivos de soja favorece las poblaciones de acridios (Orthoptera: Acrididae en el partido de Benito Juárez? Does the direct tillage practice in soybean crops favour grasshopper populations (Orthoptera: Acrididae, in Benito Juárez county?

    Directory of Open Access Journals (Sweden)

    Daniel Scuffi

    2012-12-01

    Full Text Available Considerando el desarrollo del cultivo de soja en siembra directa en el partido de Benito Juárez, y que algunos autores sostienen que esta práctica favorece los acridios, se evaluó la riqueza de especies y la abundancia en soja con siembra directa y convencional. Se registraron siete especies (Aleuas lineatus Stål, Covasacris pallidinota (Bruner, Baeacris pseudopunctulatus (Ronderos, Dichroplus elongatus Giglio-Tos, Dichroplus maculipennis (Blanchard, Dichroplus pratensis Bruner y Scotussa lemniscata (Stål. La riqueza de especies acumulada en los diferentes cultivos fue similar (p> 0,05. En soja de primera con siembra directa, se registraron 2,3 ± 0,19 especies, en soja de primera con siembra convencional 1,45 ± 0,15 especies y en soja de segunda con siembra directa 2,25 ± 0,28 especies. Dichroplus elongatus fue la especie más abundante en todos los cultivos y en todos los momentos. Las restantes presentaron baja abundancia y se registraron en algunos momentos. No existió diferencia (p> 0,05 en la abundancia de tucuras entre los cultivos y en las diferentes fechas de muestreo. La baja riqueza de especies registrada estaría relacionada con la baja diversidad vegetal de los cultivos. Este estudio no mostró diferencias en la abundancia y riqueza de especies de acuerdo a la labranza utilizada.Considering the development of the soybean crops using direct tillage in Benito Juárez county, and taking into account that for some authors this practice favours the grasshopper populations, the abundance and species richness in soybean with direct and conventional tillage were evaluated. Seven species were registered (Aleuas lineatus Stål, Covasacris pallidinota (Bruner, Baeacris pseudopunctulatus (Ronderos, Dichroplus elongatus Giglio-Tos, Dichroplus maculipennis (Blanchard, Dichroplus pratensis Bruner and Scotussa lemniscata (Stål. The accumulated richness was similar (p> 0.05, along the different crops; 2.3 ± 0.19 species were registered in

  15. A MORPHOMETRIC STUDY OF THE VARIEGATED GRASSHOPPER

    African Journals Online (AJOL)

    BIG TIMMY

    Department of Zoology, Obafemi Awolowo University, Ile-Ife, Nigeria. Correspondence a. Morphometry of the dry-season population of adult ... female specimens from Port-Harcourt were the most correctly classified compared to specimens from other locations . The present study demonstrated the morphological similarities ...

  16. Why Does the Grasshopper Not Eat Spinach

    Indian Academy of Sciences (India)

    way through Inner Mongolia just in time for the start of the games. .... (Reprinted with permission from Canadian Journal Of Chemistry, Vol.73, p.591, ... predatory mites, wasps, spiders, and beetles and effective for Integrated Pest Management.

  17. Abundance and guild structure of grasshoppers (Orthoptera ...

    African Journals Online (AJOL)

    1995-01-18

    Jan 18, 1995 ... April, 1994, we compared the abundance and guild structure .... was placed in a functional group on the basis of taxonomic ... hypothesis that they would be unaffected by changes in the ..... spatial separation from the heavily grazed area. the lightly ..... found to increase (Morris 1967, 1969, 1979; Morris &.

  18. Commercialization of Ruspolia nitidula (nsenene grasshoppers) in ...

    African Journals Online (AJOL)

    African Journal of Food, Agriculture, Nutrition and Development ... A study was, therefore, conducted to document consumers' perceptions about eating these R. nitidula; marketing chain, market locations, and the people trading ... men and characterized by wholesalers who buy R. nitidula from collectors and sell to retailers.

  19. Bug City: Crickets, Grasshoppers & Friends [Videotape].

    Science.gov (United States)

    1998

    "Bug City" is a video series created to help children (grades 1-6) learn about insects and other small critters. All aspects of bug life are touched upon, including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic…

  20. Análise faunística de gafanhotos na Floresta Nacional de Chapecó, Santa Catarina Faunistic analyses of grasshoppers in the National Forest of Chapecó, Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    Cladis Juliana Lutinski

    2011-03-01

    Full Text Available

    Realizou-se a análise faunística de gafanhotos coletados em três constituições vegetais da Flona de Chapecó. Coletas semanais foram realizadas em áreas de eucalipto, mata nativa e pinus durante o período de dezembro de 2003 a dezembro de 2004. Utilizaram-se armadilhas do tipo “pitfall”, rede de varredura, guarda-chuva entomológico e “malaise”. A fauna encontrada nas diferentes áreas foi caracterizada por meio dos índices de abundância, constância, dominância e frequência. Dezoito espécies foram comuns para as três áreas. As espécies Staurorhectus logicornis logicornis, Cylindrotettix sp. e Ommexecha virens ocorreram apenas em eucaliptos e pínus, enquanto, Scotussa lemniscata e Zoniopoda tarsata ocorreram para eucaliptos e mata nativa enquanto Amblytropidia sp. ocorreu somente em mata nativa e pínus. Tridactylus politus ocorreu somente em pínus. As espécies Allotruxalis gracilis, Dichroplus elongatus, Dichroplus misionensis e Ronderosia bergi foram muito frequentes, dominantes e muito abundantes na área de eucaliptos. A. gracilis, Metaleptea adspersa e D. misionensis foram muito frequentes, dominantes e muito abundantes na área de mata nativa. Metaleptea adspersa e R. bergi foram muito frequentes, dominantes e muito abundantes na área de pínus. Observou-se uma semelhança na diversidade de espécies entre as áreas, com maior abundância para a área de eucaliptos.

    doi: 10.4336/2011.pfb.31.65.43

    A study of the grasshopper fauna was performed through samples collected in three vegetal types in the National Forest of Chapecó. Weekly collections were carried out from December 2003 to December 2004. Pitfall traps, sweep nets, entomological umbrellas and malaise traps were used. Collections were repeated in areas with eucalyptus trees, native

  1. Mitotic effects of monochromatic ultraviolet radiation at 225, 265, and 280 nm on eleven stages of the cell cycle of the grasshopper neuroblast in culture. II. Changes in progression rate and cell sequence between the stage irradiated and nuclear membrane breakdown

    International Nuclear Information System (INIS)

    Carlson, J.G.

    1976-01-01

    Portions of embryos of the grasshopper, Chortophaga viridifasciata (DeGeer), were cultured in hanging drops under quartz cover slips. Immediately after exposure to 225, 265, or 280 nm radiation, microscope observations at 38 0 C were begun. The morphologically identified stage and the time after treatment of selected neuroblasts were recorded at short-time intervals until prometaphase was reached. Mitotic retardation induced by irradiation of prereplication stages (metaphase, anaphase, or early telophase) or S phase (middle or late telophase, interphase, or very early prophase) is greatest in postreplication stages (early, middle, and late prophase) and absent or minimal in stages morphologically identified as parts of S phase. Ultraviolet irradiation superimposes on the normal diversity of progression rates an additional variation factor, so that cells do not necessarily reach prometaphase in the order of their sequence at the time of treatment. This suggests the need for caution in ascribing particular radiosensitivities to substages of limited duration on the basis of the order in which they attain a subsequent stage

  2. Caracterización de las comunidades de acridios (Orthoptera: Acridoidea del partido de Benito Juárez, sudeste de la provincia de Buenos Aires, Argentina Grasshopper (Orthoptera: Acridoidea community structure in Benito Juárez county, in outhern Buenos Aires province, Argentina

    Directory of Open Access Journals (Sweden)

    María Laura de Wysiecki

    2004-12-01

    que motivaron este cambio en la dominancia ya que no se cuenta con datos históricos, no pueden descartarse entre otros factores, eventuales cambios climáticos, campañas acridianas y contra otras plagas y el cambio en los patrones del uso de la tierra ocurridos en las últimas décadas en el área de estudio.The structure of grasshopper communities was studied at different sites in Benito Juárez county, Buenos Aires province, Argentina, over a six-year period (1997-2002. The sites were classified into five categories of disturbance: native grasslands, halophilous communities, pastures, moderately and highly disturbed pastures. A total of 23 grasshopper species was collected. Melanoplinae was the most abundant subfamily in all sites, except for halophilous communities that were characterized by the presence of one Acridinae species, Covasacris pallidinota (Bruner. Average species richness per site and per year, ranged from 2.10 ± 0.60 species in moderately disturbed pastures to 6.20 ± 0.58 species in halophilous communities. Cumulative species richness was: 17 in native grasslands, 14 in halophilous communities, 19 in undisturbed pastures, 18 in moderately disturbed pastures and 14 in highly disturbed pastures. Mean density was significantly higher in 2001 and 2002 than in the remaining years. The most abundant species were Dichroplus pratensis Bruner and Dichroplus elongatus Giglio-Tos in native grasslands and highly disturbed pastures; C. pallidinota in halophilous communities and D. elongatus - Scotussa lemniscata (Stål in undisturbed and moderately disturbed pastures. Along the study, the taxonomic structure of the grasshopper assemblages was significantly constant in native grasslands, halophilous communities and undisturbed pastures. The pattern of species distribution showed few species widely or intermediately distributed, whereas numerous species were rare. Among the 23 species collected, D. elongatus was the most broadly distributed of all. Historically

  3. Effects of management practices on grassland birds: Grasshopper Sparrow

    Science.gov (United States)

    Dechant, Jill A.; Sondreal, Marriah L.; Johnson, Douglas H.; Igl, Lawrence D.; Goldade, Christopher M.; Nenneman, Melvin P.; Euliss, Betty R.

    1998-01-01

    Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 5,500 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental components or keys to management for the species. A section on breeding range outlines the current breeding distribution of the species in North America, including areas that could not be mapped using BBS data. The suitable habitat section describes the breeding habitat and occasionally microhabitat characteristics of the species, especially those habitats that occur in the Great Plains. Details on habitat and microhabitat requirements often provide clues to how a species will respond to a particular management practice. A table near the end of the account complements the section on suitable habitat, and lists the specific habitat characteristics for the species by individual studies. A special section on prey habitat is included for those predatory species that have more specific prey requirements. The area requirements section provides details on territory and home range sizes, minimum area requirements, and the effects of patch size, edges, and other landscape and habitat features on abundance and productivity. It may be futile to manage a small block of suitable habitat for a species that has minimum area requirements that are larger than the area being managed. The Brown-headed Cowbird (Molothrus ater) is an obligate brood parasite of many grassland birds. The section on cowbird brood parasitism summarizes rates of cowbird parasitism, host responses to parasitism, and factors that influence parasitism, such as nest concealment and host density. The impact of management depends, in part, upon a species' nesting phenology and biology. The section on breeding-season phenology and site fidelity includes details on spring arrival and fall departure for migratory populations in the Great Plains, peak breeding periods, the tendency to renest after nest failure or success, and the propensity to return to a previous breeding site. The duration and timing of breeding varies among regions and years. Species' response to management summarizes the current knowledge and major findings in the literature on the effects of different management practices on the species. The section on management recommendations complements the previous section and summarizes specific recommendations for habitat management provided in the literature. If management recommendations differ in different portions of the species' breeding range, recommendations are given separately by region. The literature cited contains references to published and unpublished literature on the management effects and habitat requirements of the species. This section is not meant to be a complete bibliography; for a searchable, annotated bibliography of published and unpublished papers dealing with habitat needs of grassland birds and their responses to habitat management, use the Grassland and Wetland Birds Bibliography on the home page of this resource.

  4. A new pygmy grasshopper species (Tetrigidae: Tetriginae) from Central India.

    Science.gov (United States)

    Gupta, Sunil Kumar

    2016-03-30

    Ergatettix subtruncatus sp. nov. is described from Durg district of Chhattisgarh, India. The new species is similar to Ergatettix callosus (Hancock, 1915), but differs from the latter by frontal cost bifurcation starts at the level of upper margin of compound eyes; median carina of vertex indistinct; posterior angle of lateral lobes of pronotum not broad, apex subtruncate, narrow; mid femur slender with small white hairs and 3indistinct lobes; dorsal valve of ovipositor less flattened. A distribution map of Ergatettix subtruncatus sp. nov. and a key to known species of the genus Ergatettix Kirby, 1914 from the Indian subcontinent is provided. The type specimens are deposited in the Central Entomological Laboratory (CEL), Zoological Survey of India, Kolkata.

  5. Breeding biology and nestling development of the Grasshopper ...

    African Journals Online (AJOL)

    Growth rate of body mass, tarsus, wing and primary feathers were similar between sexes, which showed significant but moderate body mass dimorphism at fledging (♂85–90% of ♀). Second hatchlings were smaller ... Keywords: ageing, Butastur rufipennis, hatch order, reproduction, siblicide. OSTRICH 2012, 83(3): 137– ...

  6. Antennal sensilla of grasshoppers (Orthoptera: Acrididae) in relation ...

    Indian Academy of Sciences (India)

    Unknown

    number of antennal sensillae varied among different sexes, subfamilies, ... Males showed significantly more sensillae than females, due to presence of more short basiconic and ..... were conducted to the primary olfactory center of the brain,.

  7. New insights from a high-resolution look at gastrulation in the sea urchin, Lytechinus variegatus.

    Science.gov (United States)

    Martik, Megan L; McClay, David R

    2017-12-01

    Gastrulation is a complex orchestration of movements by cells that are specified early in development. Until now, classical convergent extension was considered to be the main contributor to sea urchin archenteron extension, and the relative contributions of cell divisions were unknown. Active migration of cells along the axis of extension was also not considered as a major factor in invagination. Cell transplantations plus live imaging were used to examine endoderm cell morphogenesis during gastrulation at high-resolution in the optically clear sea urchin embryo. The invagination sequence was imaged throughout gastrulation. One of the eight macromeres was replaced by a fluorescently labeled macromere at the 32 cell stage. At gastrulation those patches of fluorescent endoderm cell progeny initially about 4 cells wide, released a column of cells about 2 cells wide early in gastrulation and then often this column narrowed to one cell wide by the end of archenteron lengthening. The primary movement of the column of cells was in the direction of elongation of the archenteron with the narrowing (convergence) occurring as one of the two cells moved ahead of its neighbor. As the column narrowed, the labeled endoderm cells generally remained as a contiguous population of cells, rarely separated by intrusion of a lateral unlabeled cell. This longitudinal cell migration mechanism was assessed quantitatively and accounted for almost 90% of the elongation process. Much of the extension was the contribution of Veg2 endoderm with a minor contribution late in gastrulation by Veg1 endoderm cells. We also analyzed the contribution of cell divisions to elongation. Endoderm cells in Lytechinus variagatus were determined to go through approximately one cell doubling during gastrulation. That doubling occurs without a net increase in cell mass, but the question remained as to whether oriented divisions might contribute to archenteron elongation. We learned that indeed there was a biased orientation of cell divisions along the plane of archenteron elongation, but when the impact of that bias was analyzed quantitatively, it contributed a maximum 15% to the total elongation of the gut. The major driver of archenteron elongation in the sea urchin, Lytechinus variagatus, is directed movement of Veg2 endoderm cells as a narrowing column along the plane of elongation. The narrowing occurs as cells in the column converge as they migrate, so that the combination of migration and the angular convergence provide the major component of the lengthening. A minor contributor to elongation is oriented cell divisions that contribute to the lengthening but no more than about 15%. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Distribution of the Sunda Colugo (Galeopterus variegatus) in Malaysia (Peninsular, Sabah, Sarawak)

    OpenAIRE

    Nasir, Muhammad Dzulhelmi Muhammad; Abdullah, Mohd Tajuddin

    2010-01-01

    There is not much information available on the distribution of the Sunda colugo (Galeopterus variegates) in Malaysia, despite it being one of only two known species in the order Dermoptera. Data on the presence of the Sunda colugo and the vernacular names used by various ethnic groups throughout Malaysia were collected and compiled from various primary and secondary sources. There were 27 locations from Peninsular, 11 locations from Sabah and 34 locations from Sarawak that reported the presen...

  9. Endogenous lentivirus in Malayan colugo (Galeopterus variegatus), a close relative of primates

    Czech Academy of Sciences Publication Activity Database

    Hron, Tomáš; Fábryová, Helena; Pačes, Jan; Elleder, Daniel

    2014-01-01

    Roč. 11, č. 84 (2014) ISSN 1742-4690 R&D Projects: GA MŠk(CZ) LK11215 Grant - others:GA MŠk(CZ) LM2010005 Institutional support: RVO:68378050 Keywords : Endogenous lentiviruses * Dermoptera * Paleovirology Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.185, year: 2014

  10. Social behavior between mothers ´ young of sloths Bradypus variegatus SCHINZ, 1825 (Xenarthra: Bradypodidae

    Directory of Open Access Journals (Sweden)

    SOARES C. A.

    2002-01-01

    Full Text Available This study is a contribution to the ex situ and in situ conservation and preservation of Sloths. The behavioral records of the social interaction between mothers and offspring allow the detection of important learning interactions and psychomotor development. The results provide valuable information that may assist in improving management conditions of captive orphan progeny. They also favor a more effective monitoring of released or transferred specimens. Age is of fundamental importance in deciding what is important during the release, transfer, or reintroduction of the species.

  11. Distribution of the Sunda Colugo (Galeopterus variegatus) in Malaysia (Peninsular, Sabah, Sarawak).

    Science.gov (United States)

    Nasir, Muhammad Dzulhelmi Muhammad; Abdullah, Mohd Tajuddin

    2010-12-01

    There is not much information available on the distribution of the Sunda colugo (Galeopterus variegates) in Malaysia, despite it being one of only two known species in the order Dermoptera. Data on the presence of the Sunda colugo and the vernacular names used by various ethnic groups throughout Malaysia were collected and compiled from various primary and secondary sources. There were 27 locations from Peninsular, 11 locations from Sabah and 34 locations from Sarawak that reported the presence of the Sunda colugo throughout Malaysia. The various ethnic groups of Malaysia adopted 37 different vernacular names to describe the Sunda colugo. This baseline data can be useful for the management authorities in conducting periodic monitoring and will enhance our knowledge of the population dynamics of the Sunda colugo in Malaysia.

  12. Bioconcentration and acute toxicity of polycyclic musks in two benthic organisms (Chironomus riparius and Lumbriculus variegatus)

    NARCIS (Netherlands)

    Artola-Garicano, E.; Sinnige, T.L.; Holsteijn, I. van; Vaes, W.H.J.; Hermens, J.L.M.

    2003-01-01

    In the current study, the bioconcentration behavior and acute toxicity of two polycyclic musks, Tonalide® 7-acetyl-1,1,3,4,4,6,-hexamethyl-1,2,3,4,-tetrahydronaphthalene (AHTN) and Galaxolide® 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexa-methyl-cyclopenta[γ]-2- benzopyran (HHCB), were studied in two

  13. Reproductive System of Brown-throated Sloth (Bradypus variegatus, Schinz 1825, Pilosa, Xenarthra): Anatomy and Histology.

    Science.gov (United States)

    Favoretto, S M; daSilva, E G; Menezes, J; Guerra, R R; Campos, D B

    2016-08-01

    In recent years, habitat degradation led to the decline of some populations of brown-throated sloth. The aim of this study was to describe morphological features of the female reproductive system of the species. The oval ovaries were partially surrounded by ovarian bursa. An external cortex and an inner medulla were present. Corpora lutea and corpora albicans together with follicles at various stages of development each with a single oocyte were found in the cortex. Uterine tubes were tortuous, tubular, travelled around the perimeter of the ovary and possessed a folded mucosa with ciliated pseudostratified epithelium. Uterus was simplex, with no horns and divided into three parts: a pear-shaped cranial segment and a long caudal uterine segment (both forming the body of the uterus) and two cervices. Uterus presented three layers: mucosa, lined by pseudostratified epithelium, muscular and serosa. The cervices connected the uterus to the urogenital sinus, a distensible cavity with longitudinal mucosal folds lined by transitional epithelium that extended from the external urethral orifice and the external uterine ostia to the vulva, which was lined by a keratinized stratified squamous epithelium. Brown-throated sloth presented a bipartite clitoris with paired crura, bodies and glandes. The presence of a double cervix and a bipartite clitoris was unique features of the species. © 2015 Blackwell Verlag GmbH.

  14. Cardiovascular responses to locomotor activity and feeding in unrestrained three-toed sloths, Bradypus variegatus

    Directory of Open Access Journals (Sweden)

    D.P.F. Duarte

    2004-10-01

    Full Text Available Heart rate (HR and systolic (SBP, diastolic (DBP and mean (MBP blood pressure were recorded by biotelemetry in nine conscious unrestrained sloths for 1 min every 15 min over a 24-h period. The animals were allowed to freely move in an acoustically isolated and temperature-controlled (24 ± 1ºC experimental room with light-dark cycle (12/12 h. Behavior was closely monitored through a unidirectional visor and classified as resting (sitting or suspended, feeding (chewing and swallowing embauba leaves, Cecropia adenops, or locomotor activity around the tree trunk or on the room floor. Locomotor activity caused statistically significant increases in SBP (+8%, from 121 ± 22 to 131 ± 18 mmHg, DBP (+7%, from 86 ± 17 to 92 ± 10 mmHg, MBP (+8%, from 97 ± 19 to 105 ± 12 mmHg, and HR (+14%, from 84 ± 15 to 96 ± 15 bpm compared to resting values, indicating a possible major influence of the autonomic nervous system on the modulation of cardiac function during this behavior. During feeding, the increase in blood pressure was even higher (SBP +27%, from 119 ± 21 to 151 ± 21 mmHg; DBP +21%, from 85 ± 16 to 103 ± 15 mmHg; MBP +24%, from 96 ± 17 to 119 ± 17 mmHg, while HR remained at 14% (from 84 ± 15 to 96 ± 10 bpm above resting values. The proportionally greater increase in blood pressure than in HR during feeding suggests an increase in peripheral vascular resistance as part of the overall response to this behavior.

  15. Oils of insects and larvae consumed in Africa: potential sources of polyunsaturated fatty acids

    Directory of Open Access Journals (Sweden)

    Womeni Hilaire Macaire

    2009-07-01

    Full Text Available The objective of this paper is to present the beneficial aspects of some insects consumed in sub-Saharan Africa, based on examples of insects consumed in Cameroon, to present their potential as sources of lipids and essential fatty acids. In Africa, termites, larvae of raphia weevil, caterpillars, crickets, bees, maggots, butterflies, weevil, etc. are significant sources of food. These insects belong mainly to the orders of : Isoptera, Orthoptera, Dictyoptera, Coleoptera, Hymenoptera, Lepidoptera and Diptera. Depending on the species, insects are rich in proteins, minerals (K, Ca, Mg, Zn, P, Fe and/or vitamins (thiamine/B1, riboflavine/B2, pyridoxine/B6, acid pantothenic, niacin. The composition of oils extracted from the following six insects consumed in Cameroon was investigated : larvaes of raphia weevil (Rhynchophorus phoenicis, crickets (Homorocoryphus nitidulus, grasshopper (Zonocerus variegates, termites (Macrotermes sp., a variety of caterpillars (Imbrasia sp. and an unidentified caterpillar from the forest (UI carterpillar. The extraction yields of oil were 53.75%, 67.25%, 9.12%, 49.35%, 24.44% and 20.17% respectively for raphia weevil larvae, crickets, devastating crickets, termites, Imbrasia and UI caterpillar. The oil from raphia weevil mainly contains 37.60% of palmitoleic acid and 45.46% of linoleic acid. The oil from crickets is principally made up of palmitoleic acid (27.59%, linoleic acid (45.63% and α-linolenic acid (16.19%. The oil from grasshoppers is composed of palmitoleic acid (23.83%, oleic acid (10.71%, linoleic acid (21.07%, α-linolenic acid (14.76% and γ-linolenic acid (22.54%. The main components of termite oil are : palmitic acid (30.47%, oleic acid (47.52% and linoleic acid (8.79%. Palmitic acid (36.08% and linolenic acid (38.01% are the two dominant fatty acids of Imbrasia oil. As Imbrasia oil, UI caterpillar oil is composed of palmitic acid (30.80% and linolenic acid (41.79%. Stearic acid (7.04%, oleic acid

  16. Sludge reduction by aquatic worms in wastewater treatment : with emphasis on the potential application of Lumbriculus variegatus

    NARCIS (Netherlands)

    Elissen, H.J.H.

    2007-01-01

    In wastewater treatment plants (WWTPs), large amounts of biological waste sludge are produced. In the Netherlands, the application of this sludge in agriculture or disposal in landfills is no longer allowed, mainly because of its high heavy metal content. The sludge therefore generally is

  17. Placentation in the colugos Cynocephalus volans and Galeopterus variegatus (Dermoptera) and the transition from labyrinthine to villous placentation in primates

    DEFF Research Database (Denmark)

    Carter, A. M.; Mess, A. M.

    2017-01-01

    Introduction Phylogenetics and genomics place colugos as the sister group to primates. Therefore their placentation is of interest in an evolutionary perspective. Previous accounts are fragmentary, not readily accessible and sometimes contradictory. Methods We have examined archival material...... placenta is intermediate between the labyrinthine placenta of rodents and the trabecular type of Neotropical primates....

  18. Streptococcus agalactiae infection in Nile tilapia (Oreochromis niloticus) and its transmission potential to cohabitated sheepshead minnows (Cyprinodon variegatus)

    Science.gov (United States)

    Streptococcus agalactiae has emerged as an economically important bacterial pathogen affecting global aquaculture. Worldwide aquaculture losses due to S. agalactiae are estimated around U.S. $1 billion, annually. Streptococcus agalactiae also known as a Lancefield Group B Streptococcus (GBS) is a Gr...

  19. On The Back Of A Grasshopper: The XXIV Corps And The Korean Occupation

    Science.gov (United States)

    2016-05-26

    52 Similarly to Iceberg, the Blacklist order envisioned a period of limited combat against isolated pockets of military forces that would continue to...of Defense, Joint Publication 1-02, Dictionary of Military and Associated Terms, Washington DC: Government Printing Office, 2014. Dolman, Everett

  20. Bioaccumulation of some natural radionuclides in short-antenna grasshoppers (Acrididae family, class Ortoptera)

    International Nuclear Information System (INIS)

    Dimitrova, M.; Markova, E.; Bogdanova, V.

    1996-01-01

    The seasonal accumulation of radioactive elements of the uranium-radium order in representatives of larva stages of different species of of Acrididae family has been examined. The monitoring sites are typical of the region and gave a relevant information about the natural background radiation. The process begins in the end of spring when Acrididae enter on the most intensive phase of their functional development and accumulate lots of radioisotopes not only by food but also through respiratory system and whole-body surface. Among the radioisotopes radium has an average biological absorbability, uranium - a very slight one. This fact explains the high values of radium in the ecosystems examined. Despite its low absorbability coefficient 238 U is found to a considerable extent in the investigated organisms. Because of it high mobility in soil compared to Ra 226, uranium 238 accumulates in plants by water and through trophic chain passes into the living organisms. It is found also that Acrididae accumulate later, during autumn and Bi 214. So they are a reliable bio-indicator for the radionuclides U 238, Ra 226, Pb 214 and Bi 214. It has been found that the ionizing radiation at the natural biocenoses is not only an individual irritant but also has an effect of a radioecological factor of the environment. The examinations show redistribution of the natural radionuclides as a result of economic activities

  1. Evidence for the 'grasshopper' effect and fractionation during long-range atmospheric transport of organic contaminants

    International Nuclear Information System (INIS)

    Gouin, T.; Mackay, D.; Jones, K.C.; Harner, T.; Meijer, S.N.

    2004-01-01

    Although there is indisputable evidence that long-range atmospheric transport (LRAT) of organic contaminants occurs on a global scale, uncertainties remain about the detailed mechanism and extent of this phenomenon as well as the physical-chemical properties which facilitate LRAT. In this study, we discuss how mass balance models and monitoring data can contribute to a fuller understanding of the mechanism and extent of LRAT. Specifically we address the issues of 'grasshopping' or 'hopping' (the extent to which molecules are subject to multiple hops as distinct from a single emission-deposition event) and 'global fractionation' (the differing behavior of chemicals as they are transported). It is shown that simple mass balance models can be used to assist the interpretation of monitoring data while also providing an instrument that can be used to assess the LRAT potential and the extent of hopping that organic substances may experience. The available evidence supports the notion that many persistent organic pollutants experience varying degrees of 'hopping' during their environmental journey and as a consequence become fractionated with distance from source. - Evidence for global scale fractionation and hopping of POPs is reviewed

  2. Euparatettix dandakaranyensis sp. nov. (Tetrigidae: Tetriginae)-a new pygmy grasshopper species from Central India.

    Science.gov (United States)

    Gupta, Sunil Kumar

    2016-03-29

    Euparatettix dandakaranyensis Gupta sp. nov. is described from Bastar, Chhattisgarh, India. A brief comparison with the type specimen of Euparatettix sikkimensis (Hancock, 1915) formerly placed within the genus Xistra is given. A key to the species of the genus Euparatettix known from the Indian subcontinent is provided.

  3. Hedotettix angulatus sp. nov. (Orthoptera: Tetrigoidea:Tetrigidae, Tetriginae) a new pygmy grasshopper species from India.

    Science.gov (United States)

    Gupta, Sunil Kumar; Shi, Jian-Ping; Chandra, Kailash

    2016-10-06

    Hedotettix angulatus sp. nov. is described from Chhattisgarh, India. The new species is similar to Hedotettix grossus Hancock, 1915, it differs from the latter by (i) anterior margin of vertex angulate, (ii) ovipositor robust, length of upper valves 2.2 times its width, (iii) antennal grooves situated above the lower margin of the compound eyes, (iv) median carina of vertex strong and extended up to the posterior end of depression, (v) facial carinae are all most parallel, (vi) frontal costa bifurcation starts in about ¼ of the compound eye height, (vii) anterior margin of middle carina of pronotum depressed. A key to known species of the genus Hedotettix from the Indian subcontinent is provided. Type specimens are deposited in the Central Entomological Laboratory (CEL) of the Zoological Survey of India, Kolkata.

  4. Triplex configuration in the nick-free DNAs that constitute the chromosomal scaffolds in grasshopper spermatids

    Czech Academy of Sciences Publication Activity Database

    Černá, Adriana; Lopez-Fernandez, C.; Fernandez, J.L.; de la Espina, S.M.D.; De la Torre, C.; Gosalvez, J.

    2008-01-01

    Roč. 117, č. 1 (2008), s. 15-24 ISSN 0009-5915 Institutional research plan: CEZ:AV0Z50380511 Keywords : chromatid scaffold * DNA loops * triplex DNA Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.111, year: 2008

  5. The Ant and the Grasshopper: A Program for Adopting Microcomputer Graphics in the Arts.

    Science.gov (United States)

    Youngblood, Michael S.

    1988-01-01

    Discusses the major reasons why microcomputers have not yet become commonplace in the arts and describes how the College of Communications and Fine Arts at Southern Illinois University (Carbondale) researched, planned, and implemented a college-wide computer technology program. (GEA)

  6. Gut Transcriptome Analysis Shows Different Food Utilization Efficiency by the Grasshopper Oedaleous asiaticus (Orthoptera: Acrididae).

    Science.gov (United States)

    Huang, Xunbing; McNeill, Mark Richard; Ma, Jingchuan; Qin, Xinghu; Tu, Xiongbing; Cao, Guangchun; Wang, Guangjun; Nong, Xiangqun; Zhang, Zehua

    2017-08-01

    Oedaleus asiaticus B. Bienko is a persistent pest occurring in north Asian grasslands. We found that O. asiaticus feeding on Stipa krylovii Roshev. had higher approximate digestibility (AD), efficiency of conversion of ingested food (ECI), and efficiency of conversion of digested food (ECD), compared with cohorts feeding on Leymus chinensis (Trin.) Tzvel, Artemisia frigida Willd., or Cleistogenes squarrosa (Trin.) Keng. Although this indicated high food utilization efficiency for S. krylovii, the physiological processes and molecular mechanisms underlying these biological observations are not well understood. Transcriptome analysis was used to examine how gene expression levels in O. asiaticus gut are altered by feeding on the four plant species. Nymphs (fifth-instar female) that fed on S. krylovii had the largest variation in gene expression profiles, with a total of 88 genes significantly upregulated compared with those feeding on the other three plants, mainly including nutrition digestive genes of protein, carbohydrate, and lipid digestion. GO and KEGG enrichment also showed that feeding S. krylovii could upregulate the nutrition digestion-related molecular function, biological process, and pathways. These changes in transcripts levels indicate that the physiological processes of activating nutrition digestive enzymes and metabolism pathways can well explain the high food utilization of S. krylovii by O. asiaticus. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. DNA damage in grasshopper Chorthippus brunneus (Orthoptera) hatchlings following paraquat exposure.

    Science.gov (United States)

    Augustyniak, M; Nocoń, Ł; Kędziorski, A; Łaszczyca, P; Sawczyn, T; Tarnawska, M; Zawisza-Raszka, A

    2015-04-01

    Comet assay was applied to study genotoxic damage induced by paraquat (PQ) in brain cells of Chorthippus brunneus (Insecta: Orthoptera) hatchlings. Percentage of the comet fluorescence in the tail (TDNA), length of the comet tail (TL) and Olive tail moment (OTM) were used for quantitative assessment of the DNA damage. Multiple regression analysis supplemented standard statistical elaboration of the results. Increasing PQ concentrations applied either directly to the brain cells suspension (10, 50, and 250 μM PQ final concentration--in vitro protocol) or indirectly (50, 250, and 1250 μM PQ final concentration--in vivo protocol) provoked significant increase of oxidative damage to DNA (higher median TDNA and OTM values). The damage increased with time of exposure (0, 5, 15, and 30 min) following in vitro application, but decreased in longer interval (3 vs 24 h) after in vivo administration of paraquat. On contrary, median TL values did not correlate with paraquat concentration irrespectively of the exposure protocol. Possible reason of this discrepancy in light of paraquat toxicity is discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Sexual harassment in heterogeneous landscapes can mediate population regulation in a grasshopper

    NARCIS (Netherlands)

    Bauer, S.; Samietz, J.; Berger, U.

    2005-01-01

    Population regulation has been related to differences in the quality among habitats, which mediate differences in vital rates such that in poor habitats reproductive rates are lower than those in high-quality habitats. The spatial distribution of animals in such habitats depends on their preferences

  9. Bioaccumulation of some natural radionuclides in short-antenna grasshoppers (Acrididae family, class Ortoptera)

    International Nuclear Information System (INIS)

    Dimitrova, M.; Markova, E.

    1996-01-01

    The seasonal accumulation of radioactive elements of uranium-radium line in representatives of larval stages of different species of Acrididae family has been examined. This group of invertebrates is a good bioindicator of radionuclides accumulation and could be used successfully as an ecological evaluation. The monitoring sites are typical for the region of Etropole (where the uranium mine 'Elatsite' is situated) and offer information about the natural radiation background as well as about an eventual radiation pollution. Two years examination has been carried out during spring, summer and autumn on natural grass ecosystem (one of them just above the mentioned uranium mine). The gamma-spectrometric analysis of seventeen samples have shown the presence of U-238, Ra-226, Pb-214 and Bi-214. The minimal detectable activity of these radionuclides was calculated, resp. 0.25Bq, 0.49Bq, 0.07Bq and 0.12Bq. All experimental data for the four radionuclides are reliable considering Currie criterion. The meadow close to the uranium mine has shown maximal radiation background, while the control samples from nearby region have shown no presence of radionuclides. The accumulation of the radionuclides from U-Ra line is seasonal, more expressed in autumn. This fact could be explained by the biological maturity of this species in the end of summer. It has been found that the ionizing radiation in the natural biocenoses is not only an individual irritant, but also has an effect of a radioecological factor of the environment. The examinations show a redistribution of the natural radionuclides resulting from economic activities. 17 refs., 3 tabs., 3 figs

  10. The indirect effects of cheatgrass invasion: Grasshopper herbivory on native grasses determined by neighboring cheatgrass abundance

    Science.gov (United States)

    Julie Beckstead; Susan E. Meyer; Carol K. Augsperger

    2008-01-01

    Invasion biology has focused on the direct effects of plant invasion and has generally overlooked indirect interactions. Here we link theories of invasion biology and herbivory to explore an indirect effect of one invading species on associational herbivory (the effect of neighboring plants on herbivory) of native species. We studied a Great Basin shadscale (...

  11. Trait similarity patterns within grass and grasshopper communities : Multitrophic community assembly at work

    NARCIS (Netherlands)

    van der Plas, F.; Anderson, T. M.; Olff, H.

    Trait-based community assembly theory suggests that trait variation among co-occurring species is shaped by two main processes: abiotic filtering, important in stressful environments and promoting similarity, and competition, more important in productive environments and promoting dissimilarity.

  12. The significance of the grasshopper effect on the atmospheric distribution of persistent organic substances

    Science.gov (United States)

    Semeena, V. S.; Lammel, Gerhard

    2005-04-01

    Slowly degradable, semivolatile organic compounds (SOCs) may undergo more than one volatilization-transport-deposition cycle through the atmosphere (multi-hopping). The significance of this process for the potential for long-range transport (LRT) is addressed for the first time. We use a multicompartment model which in turn is based on a general circulation model. The results suggest that both transport by single-hopping and multi-hopping contribute significantly to LRT of DDT and γ-HCH (lindane) and to accumulation in high latitudes. A larger fraction of the molecules transported by multi-hopping than of the molecules transported by single-hopping is deposited to the world's oceans. Multi-hopping prevails in the boundary layer far from the source regions. However, single-hopping contributes an almost equal amount to the deposition of DDT and γ-HCH in the Arctic.

  13. Insect herbivory and vertebrate grazing impact food limitation and grasshopper populations during a severe outbreak

    Science.gov (United States)

    Interspecific competition between distantly related herbivores, as well as between large vertebrate herbivores and phytophagous insects, has received little attention. Livestock grazing is the dominant land use in western North American grasslands, where phytophagous insects can be the dominant herb...

  14. First operation of an extended range grasshopper monochromator on the Aladdin storage ring

    International Nuclear Information System (INIS)

    Brown, F.C.

    1986-01-01

    First operation of a new extended range monochromator on the 1 GeV storage ring Aladdin is described. Curves are given of output flux as a function of photon energy for the 2 m and for the 5 m gratings as measured with an NBS diode. Relatively low background and flux up to 1500 eV is obtained using a 1200 line/mm 5 m holographic grating. Highly reproducible scans were obtained of the transmission of thin films including the carbon K and titanium L edges. This reproducibility and high throughput is in large part due to the small beam size and excellent stability of Aladdin. (orig.)

  15. LANDSCAPE CHANGES IN A LOWLAND IN BENIN: ECOLOGICAL IMPACT ON PESTS AND NATURAL ENEMIES.

    Science.gov (United States)

    Boucher, A; Silvie, P; Menozzi, P; Adda, C; Auzoux, S; Jean, J; Huat, J

    2015-01-01

    Habitat management involving conservative biological control could be a good crop pest management option in poor African countries. A survey was conducted from August 2013 to July 2014 in a rainfed lowland region near Pélébina, northern Benin, in order to characterize spatiotemporal landscape changes and investigate their influence on the main crop pests and their associated natural enemies. The area was mapped mainly regarding crop fields and fallows. Visual observations were recorded and a database was compiled. Major landscape composition changes were noted between rainy and dry seasons, which affected the presence of both pests and natural enemies. Cereals (rice, maize and sorghum) and cotton were grown in the humid season, and then okra (Abelmoschus esculentus) was the dominant vegetable crop in dry season. These modifications impacted fallow abundance throughout the lowland. Different cotton (e.g. Helicoverpa armigera, Dysdercus sp., Zonocerus variegatus) or rice (e.g. Diopsis longicornis, D. apicalis) pests were observed during dry season in okra crops. Dry season surveys of Poaceae in two types of fallows ('humid', 'dry') revealed the presence of very few stem borers: only 0.04% of stems sampled were infested by stem borers, with a mean of 1.13 larvae per stem. Known cereal stem borer species such as Busseola fusco, Coniesta ignefusalis, Sesamia calamistis were not clearly identified among these larvae because of their diapausing stage and white color. Unexpected pollinators (Hymenoptera Apidae, genus Braunsapis, Ceratina and Xylocopa) and predators (Crabronidae, genus Dasyproctus) were found in the stems. Sweep-net collection of insects in humid fallows allowed us to describe for the first time in Benin seven Diopsidae species (23% of adults bearing Laboulbeniomycetes ectoparasitic fungi). Some of these species were captured in rice fields during rainy season. Parasitoids (adult Chalcidoidae and Ichneumonoidae) were observed during both seasons but their

  16. Breeding performance of the Grasshopper Buzzard (Butastur rufipennis) in a natural and a human-modified West African savanna

    NARCIS (Netherlands)

    Buij, R.; Kortekaas, K.; Krimpen, R.R.D.; Wijk, van H.J.; Zanden, S.; Iongh, de H.H.; Heitkonig, I.M.A.; Snoo, de G.R.; Komdeur, J.

    2013-01-01

    Few studies have examined raptor reproduction in response to land-use change in sub-Saharan Africa, hampering conservation efforts to address regional declines. To further our understanding of mechanisms underlying the dramatic declines of West African raptors, we examined the relationship between

  17. Muito além da cigarra e da formiga = Far beyond the ant and the grasshopper

    Directory of Open Access Journals (Sweden)

    Motta, Ana Raquel

    2014-01-01

    Full Text Available As práticas discursivas intersemióticas presentes nos cantos de trabalho são aqui abordadas através de triangulação teórica entre a análise enunciativa do discurso, a ergologia e a etnomusicologia. O objetivo principal é analisar o modo pelo qual muitas experiências humanas, em diversas culturas, desmentem o discurso da “Cigarra e da Formiga”, que caracterizo como o discurso que vincula a música (indexando toda a arte à ociosidade, que desvincula a música da vida cotidiana e que considera o trabalho apenas um peso, uma atividade meio, em que o prazer não se faz presente. Um vídeo sobre o trabalho em uma Casa de Farinha da Comunidade de Barreiras no município de Barrocas, no Estado da Bahia (Brasil é descrito e analisado, possibilitando a conclusão de que, em mutirões em que se trabalha cantando, o corpo-si (cf. SCHWARTZ integra aspectos da identidade, do cumprimento da tarefa e da memória coletiva do grupo

  18. The Grasshopper and the Ant: Motivational Responses of Low-Achieving Students to High-Stakes Testing.

    Science.gov (United States)

    Roderick, Melissa; Engel, Mimi

    2001-01-01

    Examined the responses of 102 low achieving sixth and eighth graders to Chicago's highly publicized efforts to end social promotion. Students generally described increased work efforts, and students with high levels of work effort generally had greater than average learning gains and positive outcomes in terms of promotion. About one-third of…

  19. Prospective evidence for independent nitrogen and phosphorus limitation of grasshopper (Chorthippus curtipennis) growth in a tallgrass prairie.

    Science.gov (United States)

    Rode, Madison; Lemoine, Nathan P; Smith, Melinda D

    2017-01-01

    Insect herbivores play a pivotal role in regulating plant production and community composition, and their role in terrestrial ecosystems is partly determined by their feeding behavior and performance among plants of differing nutritional quality. Historically, nitrogen (N) has been considered the primary limiting nutrient of herbivorous insects, but N is only one of many potential nutrients important to insect performance. Of these nutrients, phosphorus (P) is perhaps the most important because somatic growth depends upon P-rich ribosomal RNA. Yet relatively few studies have assessed the strength of P-limitation for terrestrial insects and even fewer have simultaneously manipulated both N and P to assess the relative strengths of N- and P-limitation. Here, we tested for potential N and P limitation, as well as N:P co-limitation, on Chorthippis curtipennis (Orthoptera, Acrididae), an abundant member of arthropod communities of central US prairies. Our results demonstrate weak evidence for both N and P limitation of C. curtipennis growth rates in laboratory feeding assays. Importantly, P-limitation was just as strong as N-limitation, but we found no evidence for NP co-limitation in our study. Furthermore, nutrient limitation was not apparent in field studies, suggesting that insect growth rates may be predominately controlled by other factors, including temperature and predation. Our results suggest that P should be jointly considered, along with N, as a primary determinant of herbivore feeding behavior under both current and future climate conditions.

  20. Ecological notes and annotated checklist of the grasshoppers (Orthoptera - Acridoidea) of the Savanna ecosystem project study area, Nylsvley.

    CSIR Research Space (South Africa)

    Gandar, MV

    1983-11-01

    Full Text Available to be the main determinant of this. Changes also occur with time because of different breeding strategies. Most species are univoltine but exhibit considerable flexibility and asynchrony in breeding. All species examined are polyphagous but diets can...

  1. Isolation and structure elucidation of neuropeptides of the AKH/RPCH family in long-horned grasshoppers (Ensifera).

    Science.gov (United States)

    Gäde, G

    1992-11-01

    An identical neuropeptide was isolated by reversed-phase high-performance liquid chromatography from the corpora cardiaca of the king cricket, Libanasidus vittatus, and the two armoured ground crickets, Heterodes namaqua and Acanthoproctus cervinus. The crude gland extracts had adipokinetic activity in migratory locusts, hypertrehalosaemic activity in American cockroaches and a slight hypertrehalosaemic, but no adipokinetic, effect in armoured ground crickets. The primary structure of this neuropeptide was determined by pulsed-liquid phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal 5-oxopyrrolidine-2-carboxylic acid residue. The C-terminus was also blocked, as indicated by the lack of digestion by carboxypeptidase A. The peptide was assigned the structure [symbol: see text]Glu-Leu-Asn-Phe-Ser-Thr-Gly-TrpNH2, previously designated Scg-AKH-II. The corpora cardiaca of the cricket Gryllodes sigillatus contained a neuropeptide which differed in retention time from the one isolated from the king and armoured ground crickets. The structure was assigned as [symbol: see text]Glu-Val-Asn-Phe-Ser-Thr-Gly-TrpNH2, previously designated Grb-AKH. This octapeptide caused hyperlipaemia in its donor species. The presence of the same peptide, Scg-AKH-II, in the two primitive infraorders of Ensifera, and the different peptide, Grb-AKH, in the most advanced infraorder of Ensifera, supports the evolutionary trends assigned formerly from morphological and physiological evidence.

  2. On the formation and functions of high and very high magnesium calcites in the continuously growing teeth of the echinoderm Lytechinus variegatus: development of crystallinity and protein involvement.

    Science.gov (United States)

    Veis, Arthur; Stock, Stuart R; Alvares, Keith; Lux, Elizabeth

    2011-01-01

    Sea urchin teeth grow continuously and develop a complex mineralized structure consisting of spatially separate but crystallographically aligned first stage calcitic elements of high Mg content (5-15 mol% mineral). These become cemented together by epitaxially oriented second stage very high Mg calcite (30-40 mol% mineral). In the tooth plumula, ingressing preodontoblasts create layered cellular syncytia. Mineral deposits develop within membrane-bound compartments between cellular syncytial layers. We seek to understand how this complex tooth architecture is developed, how individual crystalline calcitic elements become crystallographically aligned, and how their Mg composition is regulated. Synchrotron microbeam X-ray scattering was performed on live, freshly dissected teeth. We observed that the initial diffracting crystals lie within independent syncytial spaces in the plumula. These diffraction patterns match those of mature tooth calcite. Thus, the spatially separate crystallites grow with the same crystallographic orientation seen in the mature tooth. Mineral-related proteins from regions with differing Mg contents were isolated, sequenced, and characterized. A tooth cDNA library was constructed, and selected matrix-related proteins were cloned. Antibodies were prepared and used for immunolocaliztion. Matrix-related proteins are acidic, phosphorylated, and associated with the syncytial membranes. Time-of-flight secondary ion mass spectroscopy of various crystal elements shows unique amino acid, Mg, and Ca ion distributions. High and very high Mg calcites differ in Asp content. Matrix-related proteins are phosphorylated. Very high Mg calcite is associated with Asp-rich protein, and it is restricted to the second stage mineral. Thus, the composition at each part of the tooth is related to architecture and function. Copyright © 2011 S. Karger AG, Basel.

  3. Data used for Raimondo et al. 2016 "Effects of Louisiana Crude Oil on the Sheepshead Minnow (Cyprinodon variegatus) During a Life-Cycle Exposure to Laboratory Oiled Sediment"

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data are provided describing reproduction, length, weight, liver weight, and ovary weight in fish exposed to sediment spiked with weathered oil. Data are also...

  4. Do we need a definition of games?

    DEFF Research Database (Denmark)

    Eichberg, Henning

    2016-01-01

    Anmeldelse og diskussion af Bernard Suits (2014): The Grasshopper. Games, Life, and Utopia. 3rd edition. Peterborough, Ontario: Broadview......Anmeldelse og diskussion af Bernard Suits (2014): The Grasshopper. Games, Life, and Utopia. 3rd edition. Peterborough, Ontario: Broadview...

  5. Opening-Up Aesop's Fables : heteroglossia in Slade & Toni Morrison and Pascal Lemaître's "The Ant or the Grasshopper?"

    OpenAIRE

    Bragard, Véronique

    2007-01-01

    Fables, characterized by their featuring animals and containing a moral, are among the earliest forms of storytelling. With its aim to simultaneously teach and entertain, playfully imparting wisdom, fabulist thinking has been used as a complex medium of political analysis and resistance against tyranny or royal negligence, for example (see Patterson, 1991). Although they occupy a marginal position, fables are still present in children's literature. While new fables are being written, old ones...

  6. Inducible protective processes in animal systems XV: Hyperthermia enhances the Ethyl methanesulfonate induced adaptive response in meiotic cells of grasshopper Poecilocerus pictus

    Directory of Open Access Journals (Sweden)

    R. Venu

    2016-04-01

    Conclusion: There is a protection against EMS induced anomalies by hyperthermia in in vivo P. pictus. As far as our knowledge is concerned, this is the first report to demonstrate that hyperthermia enhances the EMS induced adaptive response in in vivo meiotic cells.

  7. Divergent Host Plant Adaptation Drives the Evolution of Sexual Isolation in the Grasshopper Hesperotettix viridis (Orthoptera: Acrididae) in the Absence of Reinforcement

    Science.gov (United States)

    The beginning stages of lineage divergence can be difficult to detect, as correlations between altered genotypic and phenotypic attributes are often weak early in the process. Shifts in host plant use and divergence in mating signals can lead to sexual isolation and ultimately speciation. To underst...

  8. Breeding performance of the grasshopper buzzard (Butastur rufipennis) in a natural and a human-modified West African savanna

    NARCIS (Netherlands)

    Buij, Ralph; Kortekaas, Kim; van Krimpen, Roderick R. D.; van Wijk, Rien; van der Zanden, Saskia; de Iongh, Hans H.; Heitkonig, Ignas M. A.; de Snoo, Geert R.; Komdeur, Jan; Heitkönig, Ignas M.A.

    Few studies have examined raptor reproduction in response to land-use change in sub-Saharan Africa, hampering conservation efforts to address regional declines. To further our understanding of mechanisms underlying the dramatic declines of West African raptors, we examined the relationship between

  9. Salvadoracris e Caruaruacris, novos gêneros de gafanhotos sul-americanos (Orthoptera, Acrididae Salvadoracris and Caruaruacris, new South American genera of grasshopper (Orthoptera, Acrididae

    Directory of Open Access Journals (Sweden)

    Maria Kátia Matiotti da Costa

    2006-03-01

    Full Text Available Salvadoracris gen. nov. com S. nigritus sp. nov. (espécie-tipo, do Peru (Cuzco e Caruaruacris gen. nov. com C. bivittatus sp. nov. (espécie-tipo, do Brasil, Pernambuco, são descritos e ilustrados.Salvadoracris gen. nov. with S. nigritus sp. nov. (type species from Peru, Cuzco, and Caruaruacris gen. nov. with C. bivittatus sp. nov. (type species, from Brazil, Pernambuco, are described and illustrated.

  10. A simple tentative model of the losses caused by the Senegalese grasshopper, Oedaleus senegalensis (Krauss 1877) to millet in the Sahel

    DEFF Research Database (Denmark)

    Bal, Amadou Bocar; Ouambama, Zakaria; Dieng, Ibnou

    2015-01-01

    Oedaleus senegalensis is a serious pest of millet in the Sahel, but the correlation to crop loss remains largely unknown. Therefore, the correlation between densities of O. senegalensis, defoliation level and millet yields was investigated in Niger in 2008, and a simple model to foresee the yield...

  11. AHP 33: Farmers, Fugitives, Ghosts, and Exploding Grasshoppers: Everyday Life in Horse Race Village, a Tibetan Community on the Yellow River

    Directory of Open Access Journals (Sweden)

    Rka phug Rdo rje don grub རྐ་ཕུག་རྡོ་རྗེ་དོན་གྲུབ།

    2014-12-01

    Full Text Available Rta rgyugs (Dajiu tan is a natural farming village that is part of Rka phug (Gabu Administrative Village, northwest of Khams ra (Kanbula Town, Gcan tsha (Jianzha County, Rma lho (Huangnan Tibetan Autonomous Prefecture, Mtsho sngon (Qinghai Province, PR China. Other aspects of the community are presented in terms of history, education, housing, eating, sleeping, archery, religion, livelihood, sources of cash income, stories, folktales, and photographs.

  12. Grasshoppers, crickets (Orthoptera and earwigs (Dermaptera of Tovačov gravel pit (central Moravia, Czech Republic: New locality for several thermophilous species in anthropogenic secondary habitat

    Directory of Open Access Journals (Sweden)

    Trnka Filip

    2015-12-01

    Full Text Available Study of Orthoptera and earwigs was conducted in Tovačov gravel pit in 2014. We have recorded 18 species of Orthoptera and 3 species of earwigs. The most significant recorded species are Cepero’s ground-hopper (Tetrix ceperoi, pygmy mole cricket (Xya variegata, Italian tree cricket (Oecanthus pellucens and riparian earwig (Labidura riparia. Tovačov gravel pit poses the northernmost locality of T. ceperoi and X. variegata in the Czech Republic and the northernmost known locality in Moravia for O. pellucens. For the L. riparia, we present a founding from Tovačov together with another finding from Olomouc vicinity, which is currently the northernmost locality within Moravia. Our findings display recent spatial expansion of some thermophilous species. Moreover, we emphasize importance of (post-industrial areas as secondary habitats for specialised endangered species.

  13. Biodynamics of copper oxide nanoparticles and copper ions in an oligochaete

    DEFF Research Database (Denmark)

    Thit, Amalie; Ramskov, Tina; Croteau, Marie-Noële Croteau

    2016-01-01

    the bioavailability and subcellular distribution of copper oxide (CuO) NPs and aqueous Cu (Cu-Aq) in the sediment-dwelling worm Lumbriculus variegatus. Ten days (d) sediment exposure resulted in marginal Cu bioaccumulation in L. variegatus for both forms of Cu. Bioaccumulation was detected because isotopically...

  14. 75 FR 11175 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-03-10

    ... be affected. The North American Industrial Classification System (NAICS) codes have been provided to... hoppers, plant bugs, weevils, grasshoppers, mormon crickets, locust, and beetles on all greenhouse and...

  15. 76 FR 65527 - Habitat Conservation Plan/Natural Community Conservation Plan for Yolo County, CA: Environmental...

    Science.gov (United States)

    2011-10-21

    ... virens), grasshopper sparrow (Ammodramus savannarum), tricolored blackbird (Agelaius tricolor), and... personal identifying information from public review, we cannot guarantee that we will be able to do so...

  16. Mitotic effects of monochromatic ultraviolet radiation at 225, 265, and 280 nm on eleven stages of the cell cycle of the grasshopper neuroblast in culture. I. Overall retardation from the stage irradiated to nuclear membrane breakdown

    International Nuclear Information System (INIS)

    Carlson, J.G.

    1976-01-01

    Neuroblasts of Chortophaga viridifasciata (DeGeer) in culture were exposed to different doses of 225, 265, or 280 nm ultraviolet radiations at 11 different stages and substages of the mitotic cycle and individually selected cells were timed to breakdown of the nuclear membrane. Comparisons of the effectiveness of different wavelengths on the different stages were based on the dose that reduced the cell progression rate to 67 percent of normal (D 67 ) and the slope of the regression line, i.e., the control to treated time (C/T) ratio change/erg/mm 2 at the D 67 level. Cells of the prereplication period (metaphase + anaphase + early telophase) and the S phase (middle and late telophase + interphase + very early prophase) are equally sensitive to uv and contrast sharply with the much lower sensitivity of those in the postreplication period (early and middle prophase). This can best be interpreted if chromosomal DNA is the chromophore for uv-induced mitotic retardation. Cells in the prereplication period at exposure show no wavelength effect. In the S phase all stages except middle telophase and all stages combined are significantly more sensitive to 265 and 280 nm than to 225 nm. Of the postreplication stages, early prophase is retarded significantly more by 280 than by 225 or 265 nm. The C/T ratio/erg/mm 2 is greater after exposure to 265 nm at all prereplication and replication stages, but exhibits no consistent wavelength pattern during the postreplication period. Evidence based on the orientation of the neuroblast with respect to the uv-source suggests that the chromophore for mitotic retardation does not reside within the centrosome and related structures, but may be present, at least partly, in the nucleolus

  17. CHRONIC EFFECTS OF THE HERBICIDE DIURON ON FRESHWATER CLADOCERANS,AMPHIPODS,MIDGES,MINNOWS,WORMS, AND SNAILS

    Science.gov (United States)

    The chronic effects of the herbicide diuron on survival and reproduction of Daphnia pulex, and survival and growth of the amphipod Hyalella azteca, the midge Chironomus tentans, juvenile and embro/larval fathead minnows, Pimephales promelas, annelid worms, Lumbriculus variegatus,...

  18. Observations on eggs of eublepharid lizards, with comments on the evolution of the Gekkonoidea

    NARCIS (Netherlands)

    Werner, Y.L.

    1972-01-01

    Captive specimens of Coleonyx v. variegatus, C. v. bogerti, Eublepharis macularius and Hemitheconyx caudicinctus laid parchment-shelled, moisture dependent eggs, resembling those of diplodactyline geckos and most lepidosaurians. Eublepharid eggs, including those of Aeluroscalabotes measured in

  19. Additions to the Ethiopian bird atlas: 126 new records from 14 atlas ...

    African Journals Online (AJOL)

    Species endemic to either Ethiopia or to the Abyssinian highlands (i.e. Ethiopia ... confusing taxonomy leads me to believe that my record should be left undecided for now. ..... Blue-breasted Bee-eater Merops variegatus (lafresnayii).

  20. Vondst van het schavertje Stenobothrus stigmaticus in Zeeland (Orthoptera)

    NARCIS (Netherlands)

    Bouwman, J.

    2005-01-01

    Discovery of a population of the lesser mottled grasshopper Stenobothrus stigmaticus on the Dutch coast (Orthoptera) During an inventory of the nature reserve De Vroongronden between the towns of Renesse and Burg-Haamstede (province of Zeeland) the first population of the lesser mottled grasshopper

  1. A Review of Biological Communication Mechanisms Applicable to Small Autonomous Systems

    Science.gov (United States)

    2010-09-01

    katydids, grasshoppers, beetles, moths, butterflies , ants, caterpillars, beetle larvae Hitting the ground Band-winged grasshoppers, cockroaches... butterflies and moths (Lepidoptera and Noctuidae). The Agaristid moth (e.g., Hecatesia exultans and Hecatesia thyridion) has castanet-like...Insects. The Ohio J. of Science 1957, 57 (2), 101. Bailey, W. J. The Mechanics of Stridulation in Bush Crickets (Tettigonioidea, Orthoptera): I

  2. Trophic transfer of pyrene metabolites between aquatic invertebrates

    International Nuclear Information System (INIS)

    Carrasco Navarro, V.; Leppänen, M.T.; Kukkonen, J.V.K.; Godoy Olmos, S.

    2013-01-01

    The trophic transfer of pyrene metabolites was studied using Gammarus setosus as a predator and the invertebrates Lumbriculus variegatus and Chironomus riparius as prey. The results obtained by liquid scintillation counting confirmed that the pyrene metabolites produced by the aquatic invertebrates L. variegatus and C. riparius were transferred to G. setosus through the diet. More detailed analyses by liquid chromatography discovered that two of the metabolites produced by C. riparius appeared in the chromatograms of G. setosus tissue extracts, proving their trophic transfer. These metabolites were not present in chromatograms of G. setosus exclusively exposed to pyrene. The present study supports the trophic transfer of PAH metabolites between benthic macroinvertebrates and common species of an arctic amphipod. As some PAH metabolites are more toxic than the parent compounds, the present study raises concerns about the consequences of their trophic transfer and the fate and effects of PAHs in natural environments. - Highlights: ► The trophic transfer of pyrene metabolites between invertebrates was evaluated. ► Biotransformation of pyrene by L. variegatus and C. riparius is different. ► Metabolites produced by L. variegatus and C. riparius are transferred to G. setosus. ► Specifically, two metabolites produced by C. riparius were transferred. - Some of the pyrene metabolites produced by the model invertebrates L. variegatus and C. riparius are transferred to G. setosus through the diet, proving their trophic transfer.

  3. Advanced Topology Optimization Methods for Conceptual Architectural Design

    DEFF Research Database (Denmark)

    Aage, Niels; Amir, Oded; Clausen, Anders

    2015-01-01

    This paper presents a series of new, advanced topology optimization methods, developed specifically for conceptual architectural design of structures. The proposed computational procedures are implemented as components in the framework of a Grasshopper plugin, providing novel capacities...

  4. Advanced Topology Optimization Methods for Conceptual Architectural Design

    DEFF Research Database (Denmark)

    Aage, Niels; Amir, Oded; Clausen, Anders

    2014-01-01

    This paper presents a series of new, advanced topology optimization methods, developed specifically for conceptual architectural design of structures. The proposed computational procedures are implemented as components in the framework of a Grasshopper plugin, providing novel capacities...

  5. Journal of the Cameroon Academy of Sciences - Vol 2, No 1 (2002)

    African Journals Online (AJOL)

    Observations on the Meiotic Process in the African Pest Grasshopper Taphronota thaelephora Stal. (Orthoptera : Pyrgomorphidae), EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. RA Seino, DA Focho, FA Njukeng, 3-6 ...

  6. 76 FR 80388 - Notice of Intent to Repatriate Cultural Items: U.S. Department of the Interior, National Park...

    Science.gov (United States)

    2011-12-23

    ... from a flour sack. The two items belonged to Isaac Grasshopper, who resided on the Northern Cheyenne...; Standing Rock Sioux Tribe of North & South Dakota; Three Affiliated Tribes of the Fort Berthold Reservation...

  7. SINET: Ethiopian Journal of Science - Vol 35, No 2 (2012)

    African Journals Online (AJOL)

    CHROMOSOME STUDY OF SOME GRASSHOPPER SPECIES FROM DIFFERENT LOCALITIES IN CENTRAL ETHIOPIA · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Samuel Berhanu, Kifle Dagne, Emana Getu, 117-128 ...

  8. Determination of varying consumption rates from radiotracer data

    International Nuclear Information System (INIS)

    Cadwell, L.L.; Schreckhise, R.G.

    1976-01-01

    Data obtained on the uptake and elimination of phosphorus-32 by foraging grasshoppers were utilized to estimate consumption rates of blue grama grass (Bouteloua gracilis). Grasshoppers were caged in field enclosures containing blue grama grass labeled with 32 P. Periodic measurements were made to determine the body burdens of the grasshoppers and concentration of 32 P in the grass. This information, along with a two-component exponential function which was observed to best mathematically describe the retention of acutely ingested phosphorus, provided the basis for a convolution integral of the consumption rate. The consumption rate was estimated by dividing the observed body burden of the grasshopper by the convolution integral of the input (grass concentration) and impulse (retention curve) function over each observation period. Successive calculations of the consumption rates were made at various points in time as the body burden changed from continued feeding on labeled forage

  9. Effects of land-use change and rainfall in Sudano-Sahelian West Africa on the diet and nestling growth rates of an avian predator

    NARCIS (Netherlands)

    Buij, R.; Folkertsma, I.; Kortekaas, K.; longh, De H.H.; Komdeur, J.

    2013-01-01

    Raptor populations in Sudano-Sahelian West Africa are being severely affected by widespread habitat alteration which depletes prey populations, potentially aggravated by changing rainfall patterns. We studied Grasshopper Buzzards Butastur rufipennis at nests in natural and transformed habitats in

  10. Adoption Potential of Improved Sweetpotato Varieties in Ghana ...

    African Journals Online (AJOL)

    50% yield loss), Grasshoppers (30% yield loss) and Caterpillar (20% yield loss). Pesticides (Actelic 50 EC) was extensively used in pest control. Farmers perceived that, excessive use of pesticides had a negative effect on the sweetpotato yield ...

  11. Animal Production Research Advances - Vol 5, No 4 (2009)

    African Journals Online (AJOL)

    Carcass Characteristics and Economics of Broiler Chickens Fed Different Levels of Grasshopper Meal in Place of Fish Meal · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. MA Muftau, BR Olorede, 248-251 ...

  12. A Compendium of Resistance, Sinkage and Trim, and Longitudinal Wave Cut Measurements Obtained on Model 5365

    National Research Council Canada - National Science Library

    Ratchliffe, Toby; Fullerton, Anne; Rice, James; Walker, Don; Russell, Lauren; Fu, Thomas

    2007-01-01

    .... In these experiments drag force was measured using both 6-component Kistler gages and a "traditional" block gage at the tow post location, as well as a Kistler gage located at the grasshopper bracket...

  13. Research Article

    African Journals Online (AJOL)

    2016-09-01

    Sep 1, 2016 ... for Rhinoceros/Grasshopper software is used as the main tool, given its ability to effectively calculate ... illuminating engineering, in architecture. ..... Renner, G. and A. Ekárt, Genetic algorithms in computer aided design.

  14. Effects of land-use change and rainfall in Sudano-Sahelian West Africa on the diet and nestling growth rates of an avian predator

    NARCIS (Netherlands)

    Buij, Ralph; Folkertsma, Ingrid; Kortekaas, Kim; De Iongh, Hans H.; Komdeur, Jan; Sergio, Fabrizio

    Raptor populations in Sudano-Sahelian West Africa are being severely affected by widespread habitat alteration which depletes prey populations, potentially aggravated by changing rainfall patterns. We studied Grasshopper Buzzards Butastur rufipennis at nests in natural and transformed habitats in

  15. Red River of the North, Reconnaissance Report: Bois de Sioux-Mustinka Rivers Subbasin.

    Science.gov (United States)

    1980-12-01

    grazing 10. Little bluestem-stonyhills muhly-sideoats grama community: in the more xeric areas of steep slopes and hills 11. Tame grassland community...subbasin, with typical animals consisting of the short-tailed shrew , striped skunk, meadow vole, and northern grasshopper mouse (Henderson, 1979a and b...Nlon-game mamals indicated as priority species include the Arctic shrew (Ottertail County), northern grasshopper mouse (Ottertail, Grant, Traverse

  16. Taxonomic revision of the pygmy devils (Tetrigidae: Discotettiginae) with online social media as a new tool for discovering hidden diversity

    OpenAIRE

    Skejo, Josip

    2017-01-01

    Pygmy grasshoppers (Tetrigidae) are family of small grasshoppers inhabiting humid aras, where thy feed on detritus, algae and mosses, that sometimes grow on their body. Pygmy devils (Discotettiginae) are a group of genera characterized by widened subapical antennal segments. Taxonomy and biogeograpy of all the members are reviewed by examination of large series of museum material and additional photo material found in social networks (Flickr, Facebook). In total 887 specimens o...

  17. Biodynamics of copper oxide nanoparticles and copper ions in an oligochaete, Part I

    DEFF Research Database (Denmark)

    Ramskov, Tina; Thit, Amalie; Croteau, Marie-Noelle

    2015-01-01

    Copper oxide (CuO) nanoparticles (NPs) are widely used, and likely released into the aquatic environment. Both aqueous (i.e., dissolved Cu) and particulate Cu can be taken up by organisms. However, how exposure routes influence the bioavailability and subsequent toxicity of Cu remains largely...... unknown. Here, we assess the importance of exposure routes (water and sediment) and Cu forms (aqueous and nanoparticulate) on Cu bioavailability and toxicity to the freshwater oligochaete, Lumbriculus variegatus, a head-down deposit-feeder. We characterize the bioaccumulation dynamics of Cu in L....... In nature, L. variegatus is potentially exposed to Cu via both water and sediment. However, sediment progressively becomes the predominant exposure route for Cu in L. variegatus as Cu partitioning to sediment increases...

  18. Flying lemurs – The 'flying tree shrews'? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade

    Directory of Open Access Journals (Sweden)

    Volobouev Vitaly

    2008-05-01

    Full Text Available Abstract Background Flying lemurs or Colugos (order Dermoptera represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires, the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous. Results To search for cytogenetic signatures that could help to clarify the evolutionary affinities within this superordinal group, we have established a genome-wide comparative map between human and the Malayan flying lemur (Galeopterus variegatus by reciprocal chromosome painting using both human and G. variegatus chromosome-specific probes. The 22 human autosomal paints and the X chromosome paint defined 44 homologous segments in the G. variegatus genome. A putative inversion on GVA 11 was revealed by the hybridization patterns of human chromosome probes 16 and 19. Fifteen associations of human chromosome segments (HSA were detected in the G. variegatus genome: HSA1/3, 1/10, 2/21, 3/21, 4/8, 4/18, 7/15, 7/16, 7/19, 10/16, 12/22 (twice, 14/15, 16/19 (twice. Reverse painting of G. variegatus chromosome-specific paints onto human chromosomes confirmed the above results, and defined the origin of the homologous human chromosomal segments in these associations. In total, G. variegatus paints revealed 49 homologous chromosomal segments in the HSA genome. Conclusion Comparative analysis of our map with published maps from representative species of other placental orders, including Scandentia, Primates, Lagomorpha and Rodentia, suggests a signature rearrangement (HSA2q/21 association that links Scandentia and Dermoptera to one sister clade. Our results thus provide new evidence for the hypothesis that Scandentia and Dermoptera have a closer phylogenetic relationship to each other than either of them has to Primates.

  19. Regulatory ecotoxicity testing of nanomaterials – proposed modifications of OECD test guidelines based on laboratory experience with silver and titanium dioxide nanoparticles

    DEFF Research Database (Denmark)

    Hund-Rinke, Kerstin; Baun, Anders; Cupi, Denisa

    2016-01-01

    of the sediment-living worm Lumbriculus variegatus (TG 225), activity of soil microflora (TGs 216, 217), and reproduction of the invertebrates (Enchytraeus crypticus, Eisenia fetida, TGs 220, 222). Additionally, test descriptions for two further test systems (root elongation of plants in hydroponic culture; test...

  20. Radiocaesium in fruitbodies and mycorrhizae in ectomycorrhizal fungi

    International Nuclear Information System (INIS)

    Nikolova, Ivanka; Johanson, K.J.; Dahlberg, Anders

    1997-01-01

    Fruitbodies of Suillus variegatus and Lactarius rufus and, at a maximum distance of 50 cm, the corresponding mycorrhizae, were collected on a rocky area in a coniferous forest. The tuberculate mycorrhizae collected close to S. variegatus fruitbodies were identified by the RFLP pattern to be S. variegatus mycorrhizae. In contrast the smooth brown mycorrhizae collected close to fruitbodies of L. rufus were found to be of various species - L. rufus, but also Russula sp. The 137 Cs activity concentrations in fruitbodies and the fungal part of the tuburculate mycorrhizae of S. variegatus were about the same. A local enrichment of 137 Cs within fruitbodies was studied by collecting fruitbodies growing in clusters. Between 13 and 64% of the mean ground 137 Cs deposition of the cluster area (400 or 625 cm 2 ) was found in the fruitbodies. This indicates that there might be an important fungal redistribution of 137 Cs in the forest floor during the production of fruitbodies. The distribution of 137 Cs within the fruitbodies was heterogenous. For example in Cortinarious armillatus, the 137 Cs level in the cap was 2.7 times higher compared to in the stripe. (Author)

  1. Radiocaesium in fruitbodies and mycorrhizae in ectomycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Nikolova, Ivanka [N. Pouskharov Inst. of Soil Sciences and Agroecology, Sofia (Bulgaria); Johanson, K.J. [Swedish Univ. of Agricultural Sciences, Radioecology Dept., Uppsala (Sweden); Dahlberg, Anders [Swedish Univ. of Agricultural Sciences, Forest Mycology and Pathology Dept., Uppsala (Sweden)

    1997-12-31

    Fruitbodies of Suillus variegatus and Lactarius rufus and, at a maximum distance of 50 cm, the corresponding mycorrhizae, were collected on a rocky area in a coniferous forest. The tuberculate mycorrhizae collected close to S. variegatus fruitbodies were identified by the RFLP pattern to be S. variegatus mycorrhizae. In contrast the smooth brown mycorrhizae collected close to fruitbodies of L. rufus were found to be of various species - L. rufus, but also Russula sp. The {sup 137}Cs activity concentrations in fruitbodies and the fungal part of the tuburculate mycorrhizae of S. variegatus were about the same. A local enrichment of {sup 137}Cs within fruitbodies was studied by collecting fruitbodies growing in clusters. Between 13 and 64% of the mean ground {sup 137}Cs deposition of the cluster area (400 or 625 cm{sup 2}) was found in the fruitbodies. This indicates that there might be an important fungal redistribution of {sup 137}Cs in the forest floor during the production of fruitbodies. The distribution of {sup 137}Cs within the fruitbodies was heterogenous. For example in Cortinarious armillatus, the {sup 137}Cs level in the cap was 2.7 times higher compared to in the stripe. (Author).

  2. Worm-it: converting organic wastes into sustainable fish feed by using aquatic worms

    NARCIS (Netherlands)

    Elissen, H.J.H.; Hendrickx, T.L.G.; Temmink, H.; Laarhoven, B.; Buisman, C.J.N.

    2015-01-01

    Due to overfishing and the use of one-third of wild fish catches for feeding farmed fish and livestock, there is a strong need for alternative sources of suitable proteins and lipids in fish feeds. Small freshwater worms of the species Lumbriculus variegatus can be such a source based on their high

  3. Hypogeous fungi from Southern Spanish semi-arid lands

    NARCIS (Netherlands)

    Honrubia, M.; Cano, A.; Molina-Niñirola, C.

    1992-01-01

    Six hypogeous fungi of Ascomycotina and Basidiomycotina have been studied from semiarid zones in Southern Spain. Melanogaster variegatus (Vitt.) Tul. is recorded for the first time from Spain. Picoa juniperi Vitt. and Terfezia claveryi Chat. are revealed as the most frequent species in semi-arid

  4. Development of a test method to access the sludge reduction potential of aquatic organisms in activated sludge

    NARCIS (Netherlands)

    Buijs, B.R.; Klapwijk, A.; Elissen, H.J.H.; Rulkens, W.H.

    2008-01-01

    This article shows the development of a quantitative sludge reduction test method, which uses the sludge consuming aquatic worm Lumbriculus variegatus (Oligochaeta, Lumbriculidae). Essential for the test are sufficient oxygen supply and the presence of a non-stirred layer of sludge for burrowing of

  5. MAXIMIZING GROWTH AND SEXUAL MATURATION OF SHEEPSHEAD MINNOWS IN SUPPORT OF MULTI-GENERATION TEST DEVELOPMENT

    Science.gov (United States)

    Hemmer, R.L., G.M. Cripe and L.R. Goodman. In press. Maximizing Growth and Sexual Maturation of Sheepshead Minnows (Cyprinodon variegatus) in Support of Multi-Generation Test Development (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland...

  6. Valorization of waste streams, "From food by-products to worm biomass"

    NARCIS (Netherlands)

    Laarhoven, B.; Elissen, H.J.H.; Temmink, B.G.; Buisman, C.J.N.

    2013-01-01

    A new technology is investigated to produce a high quality animal feed source by converting safe industrial food wastes into worm biomass. The freshwater worm Lumbriculus variegatus (common name: blackworm) has been selected for this purpose. This species can be used to reduce and concentrate

  7. Design parameters for sludge reduction in an aquatic worm reactor

    NARCIS (Netherlands)

    Hendrickx, T.L.G.; Temmink, B.G.; Elissen, H.J.H.; Buisman, C.J.N.

    2010-01-01

    Reduction and compaction of biological waste sludge from waste water treatment plants (WWTPs) can be achieved with the aquatic worm Lumbriculus variegatus. In our reactor concept for a worm reactor, the worms are immobilised in a carrier material. The size of a worm reactor will therefore mainly be

  8. The effect of operating conditions on aquatic worms eating waste sludge

    NARCIS (Netherlands)

    Hendrickx, T.L.G.; Temmink, H.; Elissen, H.J.H.; Buisman, C.J.N.

    2009-01-01

    Several techniques are available for dealing with the waste sludge produced in biological waste water treatment. A biological approach uses aquatic worms to consume and partially digest the waste sludge. In our concept for a worm reactor, the worms (Lumbriculus variegatus) are immobilised in a

  9. Aquatic worms eat sludge: mass balances and processing of worm faeces

    NARCIS (Netherlands)

    Hendrickx, T.L.G.; Temmink, B.G.; Elissen, H.J.H.; Buisman, C.J.N.

    2010-01-01

    Reduction of the amount of waste sludge from waste water treatment plants (WWTPs) can be achieved with the aquatic worm Lumbriculus variegatus in a new reactor concept. In addition to reducing the amount of waste sludge, further processing of produced worm faeces and released nutrients should also

  10. Aquatic worms eating waste sludge in a continuous system

    NARCIS (Netherlands)

    Hendrickx, T.L.G.; Temmink, B.G.; Elissen, H.J.H.; Buisman, C.J.N.

    2009-01-01

    Aquatic worms are a biological approach to decrease the amount of biological waste sludge produced at waste water treatment plants. A new reactor concept was recently introduced in which the aquatic oligochaete Lumbriculus variegatus is immobilised in a carrier material. The current paper describes

  11. A new Sumatran species of the Clerid genus Callimerus

    NARCIS (Netherlands)

    Gorham, H.S.

    1882-01-01

    Nigro-cyaneus, squamis albis variegatus; ore, antennis, palpis, pedibusque pallidis; occipite, prothoracis disco, elytris maculis duabus lateralibus, alteraque suturali communi, et fascia postica nudata coeruleis, his striato punctatis. — Long. 8 millim. ♂. This lovely little Callimerus is allied to

  12. Biodynamics of copper oxide nanoparticles and copper ions in an oligochaete – Part I: Relative importance of water and sediment as exposure routes

    Energy Technology Data Exchange (ETDEWEB)

    Ramskov, Tina, E-mail: tramskov@hotmail.com [Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, Universitetsvej 1, DK-4000 Roskilde (Denmark); US Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025 (United States); Thit, Amalie, E-mail: athitj@ruc.dk [Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, Universitetsvej 1, DK-4000 Roskilde (Denmark); Croteau, Marie-Noële, E-mail: mcroteau@usgs.gov [US Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025 (United States); Selck, Henriette, E-mail: selck@ruc.dk [Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, Universitetsvej 1, DK-4000 Roskilde (Denmark); US Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025 (United States)

    2015-07-15

    Highlights: • Both aqueous and nanoparticulate Cu forms are available for uptake by L. variegatus. • Cu accumulation is driven by both water and sediment uptake. • Cu form weakly influences Cu biodynamics in L. variegatus. • Food ingestion rate is a sensitive endpoint for dietborne Cu exposure. • Stable isotope tracers allow detecting accumulation after environmentally relevant exposures. - Abstract: Copper oxide (CuO) nanoparticles (NPs) are widely used, and likely released into the aquatic environment. Both aqueous (i.e., dissolved Cu) and particulate Cu can be taken up by organisms. However, how exposure routes influence the bioavailability and subsequent toxicity of Cu remains largely unknown. Here, we assess the importance of exposure routes (water and sediment) and Cu forms (aqueous and nanoparticulate) on Cu bioavailability and toxicity to the freshwater oligochaete, Lumbriculus variegatus, a head-down deposit-feeder. We characterize the bioaccumulation dynamics of Cu in L. variegatus across a range of exposure concentrations, covering both realistic and worst-case levels of Cu contamination in the environment. Both aqueous Cu (Cu-Aq; administered as Cu(NO{sub 3}){sub 2}) and nanoparticulate Cu (CuO NPs), whether dispersed in artificial moderately hard freshwater or mixed into sediment, were weakly accumulated by L. variegatus. Once incorporated into tissues, Cu elimination was negligible, i.e., elimination rate constants were in general not different from zero for either exposure route or either Cu form. Toxicity was only observed after waterborne exposure to Cu-Aq at very high concentration (305 μg L{sup −1}), where all worms died. There was no relationship between exposure route, Cu form or Cu exposure concentration on either worm survival or growth. Slow feeding rates and low Cu assimilation efficiency (approximately 30%) characterized the uptake of Cu from the sediment for both Cu forms. In nature, L. variegatus is potentially exposed to Cu

  13. Fear on the move: predator hunting mode predicts variation in prey mortality and plasticity in prey spatial response.

    Science.gov (United States)

    Miller, Jennifer R B; Ament, Judith M; Schmitz, Oswald J

    2014-01-01

    Ecologists have long searched for a framework of a priori species traits to help predict predator-prey interactions in food webs. Empirical evidence has shown that predator hunting mode and predator and prey habitat domain are useful traits for explaining predator-prey interactions. Yet, individual experiments have yet to replicate predator hunting mode, calling into question whether predator impacts can be attributed to hunting mode or merely species identity. We tested the effects of spider predators with sit-and-wait, sit-and-pursue and active hunting modes on grasshopper habitat domain, activity and mortality in a grassland system. We replicated hunting mode by testing two spider predator species of each hunting mode on the same grasshopper prey species. We observed grasshoppers with and without each spider species in behavioural cages and measured their mortality rates, movements and habitat domains. We likewise measured the movements and habitat domains of spiders to characterize hunting modes. We found that predator hunting mode explained grasshopper mortality and spider and grasshopper movement activity and habitat domain size. Sit-and-wait spider predators covered small distances over a narrow domain space and killed fewer grasshoppers than sit-and-pursue and active predators, which ranged farther distances across broader domains and killed more grasshoppers, respectively. Prey adjusted their activity levels and horizontal habitat domains in response to predator presence and hunting mode: sedentary sit-and-wait predators with narrow domains caused grasshoppers to reduce activity in the same-sized domain space; more mobile sit-and-pursue predators with broader domains caused prey to reduce their activity within a contracted horizontal (but not vertical) domain space; and highly mobile active spiders led grasshoppers to increase their activity across the same domain area. All predators impacted prey activity, and sit-and-pursue predators generated strong

  14. Biodynamics of copper oxide nanoparticles and copper ions in an oligochaete: Part I: relative importance of water and sediment as exposure routes

    Science.gov (United States)

    Ramskov, Tina; Thit, Amalie; Croteau, Marie-Noele; Selck, Henriette

    2015-01-01

    Copper oxide (CuO) nanoparticles (NPs) are widely used, and likely released into the aquatic environment. Both aqueous (i.e., dissolved Cu) and particulate Cu can be taken up by organisms. However, how exposure routes influence the bioavailability and subsequent toxicity of Cu remains largely unknown. Here, we assess the importance of exposure routes (water and sediment) and Cu forms (aqueous and nanoparticulate) on Cu bioavailability and toxicity to the freshwater oligochaete, Lumbriculus variegatus, a head-down deposit-feeder. We characterize the bioaccumulation dynamics of Cu in L. variegatus across a range of exposure concentrations, covering both realistic and worst-case levels of Cu contamination in the environment. Both aqueous Cu (Cu-Aq; administered as Cu(NO3)2) and nanoparticulate Cu (CuO NPs), whether dispersed in artificial moderately hard freshwater or mixed into sediment, were weakly accumulated by L. variegatus. Once incorporated into tissues, Cu elimination was negligible, i.e., elimination rate constants were in general not different from zero for either exposure route or either Cu form. Toxicity was only observed after waterborne exposure to Cu-Aq at very high concentration (305 µgL-1), where all worms died. There was no relationship between exposure route, Cu form or Cu exposure concentration on either worm survival or growth. Slow feeding rates and low Cu assimilation efficiency (approximately 30%) characterized the uptake of Cu from the sediment for both Cu forms. In nature, L. variegatus is potentially exposed to Cu via both water and sediment. However, sediment progressively becomes the predominant exposure route for Cu in L. variegatus as Cu partitioning to sediment increases.

  15. Risk from cattle trampling to nests of an endangered passerine evaluated using artificial nest experiments and simulations

    Directory of Open Access Journals (Sweden)

    Brian W. Rolek

    2016-06-01

    Full Text Available Grasslands are often grazed by cattle and many grassland birds nest on the ground, potentially exposing nests to trampling. We tested for trampling risk introduced by cattle to nests of endangered Florida Grasshopper Sparrows (Ammodramus savannarum floridanus using experimentally paired grids of artificial nests (i.e., clay targets similar in size to nests of Florida Grasshopper Sparrows and counted the number of clay targets that were broken in paired grazed and ungrazed enclosures. Clay targets in grazed grids were trampled 3.9% more often than their respective ungrazed grids, and measurements of cattle presence or density were correlated with the number of broken clay targets, suggesting that excluding cattle during breeding is an important management recommendation for the Florida Grasshopper Sparrow. Trampling rates within grazed enclosures were spatially homogeneous with respect to cattle infrastructure such as supplemental feeding troughs and fences, and forests and stocking density were poor predictors of trampling rates when excluding ungrazed grids. We used population viability analysis to compare quasi-extinction rates, intrinsic growth rates, and median abundance in grazed and ungrazed Florida Grasshopper Sparrow aggregations to further understand the biological significance of management aimed at reducing trampling rates during the breeding season. Simulations indicated that trampling from grazing increased quasi-extinction rates by 41% while reducing intrinsic growth rates by 0.048, and reducing median abundance by an average of 214 singing males after 50 years. Management should avoid grazing enclosures occupied by Florida Grasshopper Sparrows during the nesting season to minimize trampling rates. Our methods that combine trampling experiments with population viability analysis provide a framework for testing effects from trampling on other grassland ground-nesting birds, and can directly inform conservation and management of the

  16. Relaciones tróficas de cinco peces costeros comunes en el área submareal del norte de Chile (20°11'-20°20'S

    Directory of Open Access Journals (Sweden)

    Mauricio Vargas

    1999-09-01

    Full Text Available The trophic relations of five coastal Perciformes at northern Chile were analyzed on the basis of 151 specimens of Acanthistius pictus, Paralabrax humeralis, Pinguipes chilensis, Anisotremus scapularis and Cheilodactylus variegatus collected off Iquique, in April 1996, as a preliminary way to identify trophic guilds of subtidal fishes; A. pictus, P. humeralis and C. variegatus, had the crustaceans Rhynchocynetes typus, Pseudosquillopsis lessoni and Allopetrolisthes angulosus, respectively, as the best represented items. In A. scapularis and P. chilensis the best represented items were the mollusks; however for the last species, the main food was the crustacean Cancer setosus. These fish are essentially benthophagous carnivores with a variable trophic spectrum(8 to 36 items.

  17. Determinants of species richness patterns in the Netherlands across multiple taxonomic groups

    NARCIS (Netherlands)

    Schouten, M.A.; Verweij, P.A.; Barendrecht, A.; Kleukers, R.

    2009-01-01

    We examined the species richness patterns of five different species groups (mosses, reptiles and amphibians, grasshoppers and crickets, dragonflies, and hoverflies) in the Netherlands (41,500 km2) using sampling units of 5 × 5 km. We compared the spatial patterns of species richness of the five

  18. Resonance journal of science education

    Indian Academy of Sciences (India)

    IAS Admin

    810 Grasshoppers – Generalists to Specialists? S V Eswaran and Akanksha Jindal. 817 Application of Analytical Geometry to the Form of. Gear Teeth. V G A Goss. SERIES ARTICLES. 832 Circadian Rhythms. The Underlying Molecular Mechanisms. Nikhil K L and Vijay Kumar Sharma. BOOK REVIEW. 856 Pure Delight.

  19. Proceedings of a Seminar on Applications in Water Quality Control Held at Portland, Oregon on 31 January - 1 February 1984,

    Science.gov (United States)

    1984-02-01

    on lipid conter.t ;i’ithr than or ,’rebh weight in acuatic org,;.nisrs such as mussel; and fish. c’,neider (Iq8.’) a!so -oicluded that differences in...Only above vrround vegetation was harvested. Screening was placed around and on * top of the planted sedge to keep large insects (grasshoppers) and

  20. NOTES ON THE ECOLOGY, CAPTURE AND BEHAVIOUR IN ...

    African Journals Online (AJOL)

    The lighting in the animal room corresponded to the hours of daylight. New captives, however, appeared to respond favourably to an additional light placed immediately over their cage in the middle ofthe day. The captive elephant shrews receive a diet oflocusts, grasshoppers, mealworms, occasional oranges and bananas.

  1. (Rhabdomys pumilio)

    African Journals Online (AJOL)

    Figures indicate the percentage of each food eaten per day. Preference categories are as described in the text. Otomys irroratus. Rhabdomys pumilio. One. Two. Food species day days. Insects. Grasshoppers (Acrididae). 90. Termites (Hodotermes mossambicus). 50. Cockroaches (Periplaneta americana). 30. Mealworms ...

  2. 78 FR 35951 - Proposed Low-Effect Habitat Conservation Plan for the City of Santa Cruz Graham Hill Water...

    Science.gov (United States)

    2013-06-14

    ...] Proposed Low-Effect Habitat Conservation Plan for the City of Santa Cruz Graham Hill Water Treatment Plant... grasshopper (Trimerotropis infantilis), and will address associated impacts and conservation measures for the... lawful activities associated with the operation and maintenance of the existing Graham Hill Water...

  3. Author Details

    African Journals Online (AJOL)

    Focho, DA. Vol 2, No 1 (2002) - Articles Observations on the Meiotic Process in the African Pest Grasshopper Taphronota thaelephora Stal. (Orthoptera : Pyrgomorphidae) Details PDF · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's ...

  4. Where Humans are Animals and Animals are Human

    Indian Academy of Sciences (India)

    great pleasure of devouring it in a short span of time. My pleasure ... indeed incredibly funny but at the same time, it is really ... was written from memory or based on a di- ary. Although ... “A tiny green grasshopper with a long, melan- choly face ...

  5. 125 Situation du criquet marocain "Dociostaurus maroccanusThunb ...

    African Journals Online (AJOL)

    AKA BOKO

    grasshoppers. Dociostaurus maroccanus appears able to move important distances, but it cannot be a migratory species as Locusta migratoria. Keywords : Morphometry, capacities of displacements, morphological features,. Moroccan Locust, migratory species. 1. Introduction. Contrairement à des espèces migratrices, ...

  6. The increasingly urban status of the Cattle Egret Bubulcus ibis in ...

    African Journals Online (AJOL)

    Some birds may always have fed in the area that is now Kampala. Today, some feed at the city's main land-fill site, but most go to the countryside where their consumption of bush-crickets, grasshoppers and other insects is presumably beneficial to farmers. Overall, for breeding and roosting, and to some extent feeding, ...

  7. Diet of some insectivorous passerines in semi-arid regions of South ...

    African Journals Online (AJOL)

    BrubruNilaus afer, Brown-crowned Tchagra Tchagra australis,Crimson-breasted Shrike Laniarius atrococcineus, BokmakierieTelophorus zeylonus, Pririt Batis Batis pririt (Malaconotidae), Common Fiscal Lanius collarisand Magpie Shrike Corvinella melanoleuca(Laniidae) had eaten mainly grasshoppers and beetles.

  8. Untitled

    Indian Academy of Sciences (India)

    With six large white spots. Lefroy (1909) has reported that the species belongs to the plains, but it has also been locally collected in the hilly tracts of Ajmer. (1,581 ft. above M.S.L.) by one of us (N. K.). The insect is predacious in habits and feeds on other small insects including grasshoppers. General accounts dealing with ...

  9. Effet De La Temperature Et De L\\'humidite Relative Sur Le ...

    African Journals Online (AJOL)

    killed grasshoppers appeared to be most effective resulting in up to an average of 90 % mortality and more than 62 % infection at 25 °C. Temperature significantly affected mortality and infection rates and so did incubation period. The optimum ...

  10. Ostrich: Journal of African Ornithology - Vol 83, No 3 (2012)

    African Journals Online (AJOL)

    Breeding biology and nestling development of the Grasshopper Buzzard · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. R Buij, K Kortekaas, I Folkertsma, M van der Velde, J Komdeur, HH de Iongh. http://dx.doi.org/10.2989/00306525.2012.736091 ...

  11. The influence of cropping systems on the population and build up of ...

    African Journals Online (AJOL)

    Maize and cassava inter-crops recorded the lowest population counts and highest on pigeonpea + cocoyam, pigeonpea + yam and pigeonpea sole crops. However, the population of grasshoppers were significantly higher in pigeonpea sole crops. Followed by pigeonpea + cassava inter-crops. The population of beetles ...

  12. Short communications

    African Journals Online (AJOL)

    wall of the small building on the left, the fence on the right was used by the male for perching before approaching the nest; b) sealed entrance slit of the nest in a hollow brick stone, the female's bill tip can be seen; c) the male waiting to approach the nest, car- rying a slant-faced grasshopper. (Acridinae); d) the male clings to.

  13. Resonance – Journal of Science Education | Indian Academy of ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 9. Grasshoppers – Generalists to Specialists? S V Eswaran Akanksha Jindal. General Article Volume 18 Issue 9 September 2013 pp 810-816. Fulltext. Click here to view fulltext PDF. Permanent link:

  14. Condensed tannin in Eragrostis chloromelas leaves deters feeding ...

    African Journals Online (AJOL)

    We investigated the feeding responses of a generalist grasshopper, the brown locust(Locusta pardalina), to leaves of the grass Eragrostis chloromelas differing in polyphenol content. For three specimens of E. chloromelas, the presence of condensed tannin in epidermal cells was confirmed by histochemical staining, while ...

  15. Ecology of baboons ( Papio ursinus ) at Cape Point | Davidge ...

    African Journals Online (AJOL)

    Invertebrates (ants, grasshoppers, marine shellfish) were also taken. Daily distance (3-14 km) covered by the troop while foraging was greatest in summer. Female baboons had menstrual cycles and copulated throughout the year. The calculated reproductive rate (12%) was roughly 80% of those reported for congeners ...

  16. Fish Hook Injury of Eyelid: An Unusual Case

    African Journals Online (AJOL)

    [Figure 6]. Barb can be single or multiple with different types of baits like colored feathers (to imitate insect wings) and live baits like earthworm or grasshopper. Kamath[1] described a case of fishhook injury to the eyelid in which the fish hook was loaded with live maggots. Multiple barb fishhooks are much difficult to remove.

  17. Een nieuwe vondst van het locomotiefje Chorthippus apricarius in Nederland (Orthoptera)

    NARCIS (Netherlands)

    Groenendijk, D.; Groenendijk, M.

    1999-01-01

    A new record of Chorthippus apricarius in the Netherlands (Orthoptera) Chorthippus apricarius is a very rare grasshopper in The Netherlands. Only three, very widely separated sites are known. In 1998 a small new population has been found in a roadside verge, 2 km southwest of the southernmost site

  18. Author Details

    African Journals Online (AJOL)

    Olorede, BR. Vol 5, No 2 (2009) - Articles Supplemental value of avizyme in diets of rabbits containing graded levels of wheat offal. Abstract · Vol 5, No 4 (2009) - Articles Carcass Characteristics and Economics of Broiler Chickens Fed Different Levels of Grasshopper Meal in Place of Fish Meal Abstract. ISSN: 0794-4721.

  19. Resonance – Journal of Science Education | Indian Academy of ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Akanksha Jindal. Articles written in Resonance – Journal of Science Education. Volume 18 Issue 9 September 2013 pp 810-816 General Article. Grasshoppers – Generalists to Specialists? S V Eswaran Akanksha Jindal · More Details Fulltext PDF ...

  20. Insect pests' incidence and variations due to forest landscape ...

    African Journals Online (AJOL)

    No differences were found between the intensification zones, except for weeds, which appeared to be a greater constraint in the slightly degraded area. Within the insect pest, the greatest damage to crops according to farmers originated from borers and scales, followed by variegated grasshopper. Only the termites showed ...

  1. Resonance – Journal of Science Education | News

    Indian Academy of Sciences (India)

    Grasshoppers – Generalists to Specialists? S V Eswaran Akanksha Jindal · More Details Fulltext PDF. pp 817-831 General Article. Application of Analytical Geometry to the Form of Gear Teeth · V G A Goss · More Details Fulltext PDF. pp 832-844 Series Article. Circadian Rhythms - The Underlying Molecular Mechanisms.

  2. Effects of plantation residue management on the community ...

    African Journals Online (AJOL)

    Effects of plantation residue management on the community structure of wattle regeneration invertebrate pests in South Africa. ... Members of the soil invertebrate pest complex included whitegrubs and cutworms that generally had a higher pest status than millipedes, nematodes, grasshoppers, ants, false wireworms, ...

  3. Portraits of Learning 2007: We Present This Year's Winning Student Photos

    Science.gov (United States)

    Technology & Learning, 2007

    2007-01-01

    This year's more than 4,000 Portraits of Learning entries attest to the growing comfort with digital technologies and visual arts that today's kids have. This article presents 12 winning student photos of the Portraits of Learning 2007. The winners emerged from the selection of subjects that varied wildly--from grasshoppers, giraffes, zebras, and…

  4. Parametric City Scale Energy Modeling Perspectives on using Termite in city scaled models

    DEFF Research Database (Denmark)

    Negendahl, Kristoffer; Nielsen, Toke Rammer

    Termite is a parametric tool using the Danish building performance simulation engine Be10 written for the Grasshopper3D/Rhino3D environment. The tool Be10 is originally intended for building energy frame calculations and is required by Danish law when constructing new buildings. Termite opens up...... requirements, placing solar energy production facilities etc....

  5. From my Home: Dvarionas: Elegie; Pärt: Fratres / Patric Wiklacz

    Index Scriptorium Estoniae

    Wiklacz, Patric

    1997-01-01

    Uuest heliplaadist "From my Home: Dvarionas: Elegie; Pärt: Fratres; Barkauskas: Partita; Vasks: Musica Dolorosa; Pelecis: Concerto for Violin, Piano and String Orchestra, "Neverthless"; Plakidis: Two Grasshopper Dances; Tüür: Conversio. Deutsche Kammerphilharmonie, Gidon Kremer (violon), Vadim Sacharov (piano)" Teldec 0630-14654-2 (79 minutes:DDD)

  6. From my Home: Dvarionas: Elegie / Rob Cowan

    Index Scriptorium Estoniae

    Cowan, Rob

    1997-01-01

    Uuest heliplaadist "From my Home: Dvarionas: Elegie; Pärt: Fratres; Barkauskas: Partita; Vasks: Musica Dolorosa; Pelecis: Concerto for Violin, Piano and String Orchestra, "Neverthless"; Plakidis: Two Grasshopper Dances; Tüür: Conversio. Deutsche Kammerphilharmonie. Teldec 0630-14654-2 (79 minutes:DDD)

  7. Characterization of a Composite Material to Mimic Human Cranial Bone

    Science.gov (United States)

    2015-09-01

    first of applying a continuous layer of white acrylic spray paint, followed by a mist of larger droplets of black paint to create a pattern, as shown in...Figure 4. A digital camera (Grasshopper model, Point Grey Inc.) was used to acquire images every 0.12 seconds during testing, and strain was

  8. Effects of carbaryl-bran bait on trap-catch and seed predation by ground beetles

    Science.gov (United States)

    Carbaryl-bran bait is effective against grasshoppers without many impacts on non-target organisms, but ground beetles (Coleoptera: Carabidae) may be susceptible to these baits. Carabids are beneficial in agricultural settings as predators of insect pests and weed seeds. Carabid species composition a...

  9. International Wildfire Emergencies: Management in the 21st Century

    Science.gov (United States)

    Julia V. Taft; Robert W. Mutch

    1987-01-01

    The U.S. Government, through the U.S. Agency for International Development's Office of U.S. Foreign Disaster Assistance (OFDA), responds to a wide variety of disasters throughout the world every year. These disasters range from "slow-moving" events like prolonged drought or plagues of grasshoppers and locusts to "fast-moving" threats to human...

  10. Metacridamides A and B, bioactive macrocycles from conidia of the entomopathogenic fungus Metarhizium acridum

    Science.gov (United States)

    Metarhizium acridum, an entomopathogenic fungus, has been commercialized and used successfully for biocontrol of grasshopper pests in Africa and Australia. Its conidia produce two novel 17-membered macrocycles, metacridamides A (1) and B (2), which consist of a Phe unit condensed with a nonaketide....

  11. Metacridamides A and B from the biocontrol fungus metarhizium acridum

    Science.gov (United States)

    Metarhizium acridum, an entomopathogenic fungus, has been commercialized and used successfully for biocontrol of grasshopper pests in Africa and Australia. As part of an effort to catalog the secondary metabolites of this fungus we discovered that its conidia produce two novel 17-membered macrocycl...

  12. EFFECT OF INFESTATION OF Dermestes maculatus on the ...

    African Journals Online (AJOL)

    Olusola Fasunwon

    2011-12-07

    Dec 7, 2011 ... nutrition in Africa, Asia and Latin American. Some of the most important groups of the hundreds of insect species that have been used as human food include: Grasshoppers, Rhinoceros beetles, Caterpillars, Termites, Bees, Wasps, .... grams of Oryctes boas were introduced into each container, respectively.

  13. Pathogenicity of local Metarhizium anisopliae var. acridum strains ...

    African Journals Online (AJOL)

    Locusts and grasshoppers are the most important economical threat in the sahelian agricultural system. Principal control strategies of these pests are synthetic chemicals which are, however, harmful to the environment and human health. Metarhizium anisopliae based biopesticide Green Muscle IMI330189 has been ...

  14. How does Oedipoda germanica (Orthoptera: Acrididae) cope on the northern edge of its distribution? A demographical study of a completely isolated population

    Czech Academy of Sciences Publication Activity Database

    Rada, S.; Štěpánová, L.; Losík, J.; Šipoš, Jan; Holusa, J.; Kuras, T.

    2015-01-01

    Roč. 112, č. 3 (2015), s. 486-492 ISSN 1210-5759 Institutional support: RVO:67179843 Keywords : capture-recapture experiments * marked animals * conservation * survival * habitat * size * Orthoptera * Acrididae * Oedipoda germanica * endangered grasshopper * population size * survival * temperature Subject RIV: EH - Ecology, Behaviour Impact factor: 0.975, year: 2014

  15. Valorisation of waste streams from by-product to worm biomass

    OpenAIRE

    Laarhoven, Bob

    2017-01-01

    There is a global demand for more feed resources to keep up with the increasing production of livestock. The hunger for resources is most urgent in the aquaculture sector, which to a large degree depends on the non-sustainable use of fish oil/ meal from wild fish. Aquatic macro invertebrates such as the freshwater worm Lumbriculus variegatus (Oligochaeta, Lumbriculidae, common name blackworms, further abbreviated as Lv) are rich in proteins, lipids, vitamins and minerals. When cultivated on s...

  16. Asaia symbionts interfere with infection by Flavescence dorée phytoplasma in leafhoppers

    KAUST Repository

    Gonella, Elena

    2018-03-20

    The transmission of microbial pathogens by insect vectors can be affected by the insect’s microbial symbionts, which may compete in colonizing organs, express antagonistic factors or activate host immune response. Acetic acid bacteria of the genus Asaia are symbionts of the leafhopper Scaphoideus titanus, which transmits Flavescence dorée phytoplasma. These bacteria could be used as control agents against the disease. Here, we experimentally investigated the interaction between different strains of Asaia and phytoplasma transmission in the laboratory by using the model leafhopper Euscelidius variegatus and the plant host Vicia faba. We found that uncultivable and low concentrations of Asaia phylotypes were associated with E. variegatus. When we supplied different Asaia strains isolated from other insects and exhibiting different phenotypes to E. variegatus orally, the bacteria stably colonized the leafhopper, reached relatively higher densities and could then be isolated from the host. We conducted transmission trials of Flavescence dorée phytoplasma with individuals colonized with three exogenous Asaia strains. When the phytoplasma became established in the bodies of E. variegatus, leafhoppers were able to transmit it to broad beans, with transmission rates ranging from 33 to 76% in different experiments. However, leafhoppers that were colonized by one of the Asaia strains producing an air–liquid interface biofilm exhibited significantly reduced phytoplasma acquisition, with infection rates at 5–28%, whereas they were 25–77% in control insects. Although the mechanisms regulating this interference remain to be elucidated, our results provide evidence of the potential use of Asaia as a biocontrol agent.

  17. Asaia symbionts interfere with infection by Flavescence dorée phytoplasma in leafhoppers

    KAUST Repository

    Gonella, Elena; Crotti, Elena; Mandrioli, Mauro; Daffonchio, Daniele; Alma, Alberto

    2018-01-01

    The transmission of microbial pathogens by insect vectors can be affected by the insect’s microbial symbionts, which may compete in colonizing organs, express antagonistic factors or activate host immune response. Acetic acid bacteria of the genus Asaia are symbionts of the leafhopper Scaphoideus titanus, which transmits Flavescence dorée phytoplasma. These bacteria could be used as control agents against the disease. Here, we experimentally investigated the interaction between different strains of Asaia and phytoplasma transmission in the laboratory by using the model leafhopper Euscelidius variegatus and the plant host Vicia faba. We found that uncultivable and low concentrations of Asaia phylotypes were associated with E. variegatus. When we supplied different Asaia strains isolated from other insects and exhibiting different phenotypes to E. variegatus orally, the bacteria stably colonized the leafhopper, reached relatively higher densities and could then be isolated from the host. We conducted transmission trials of Flavescence dorée phytoplasma with individuals colonized with three exogenous Asaia strains. When the phytoplasma became established in the bodies of E. variegatus, leafhoppers were able to transmit it to broad beans, with transmission rates ranging from 33 to 76% in different experiments. However, leafhoppers that were colonized by one of the Asaia strains producing an air–liquid interface biofilm exhibited significantly reduced phytoplasma acquisition, with infection rates at 5–28%, whereas they were 25–77% in control insects. Although the mechanisms regulating this interference remain to be elucidated, our results provide evidence of the potential use of Asaia as a biocontrol agent.

  18. Survival, reproduction, growth, and parasite resistance of aquatic organisms exposed on-site to wastewater treated by advanced treatment processes.

    Science.gov (United States)

    Schlüter-Vorberg, Lisa; Knopp, Gregor; Cornel, Peter; Ternes, Thomas; Coors, Anja

    2017-05-01

    Advanced wastewater treatment technologies are generally known to be an effective tool for reducing micropollutant discharge into the aquatic environment. Nevertheless, some processes such as ozonation result in stable transformation products with often unknown toxicity. In the present study, whole effluents originating from nine different steps of advanced treatment combinations were compared for their aquatic toxicity. Assessed endpoints were survival, growth and reproduction of Lumbriculus variegatus, Daphnia magna and Lemna minor chronically exposed in on-site flow-through tests based on standard guidelines. The treatment combinations were activated sludge treatment followed by ozonation with subsequent filtration by granular activated carbon or biofilters and membrane bioreactor treatment of raw wastewater followed by ozonation. Additionally, the impact of treated wastewater on the immune response of invertebrates was investigated by challenging D. magna with a bacterial endoparasite. Conventionally treated wastewater reduced reproduction of L. variegatus by up to 46%, but did not affect D. magna and L. minor with regard to survival, growth, reproduction and parasite resistance. Instead, parasite susceptibility was significantly reduced in D. magna exposed to conventionally treated as well as ozonated wastewater in comparison to D. magna exposed to the medium control. None of the three test organisms provided clear evidence that wastewater ozonation leads to increased aquatic toxicity. Rather than to the presence of toxic transformation products, the affected performance of L. variegatus could be linked to elevated concentrations of ammonium and nitrite that likely resulted from treatment failures. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. [Some ecological aspects of larvivorous fish existing in Cayo Santa María, Cuba].

    Science.gov (United States)

    Menéndez Díaz, Zulema; Manso Valdés, Eulises; Castex Rodríguez, Mayda; Fuentes González, Omar; Hernández Contreras, Natividad; García Avila, Israel

    2007-01-01

    One thousand and three hundred twenty one fish from Cyprinodon variegatus, Gambusia punticulata, Fundulus grandis saguanus. Cubanichthys cubensis y Girardinus metallicus were collected for the purpose of locating and identifying fish of interest in the control of mosquito larvae in Cayo Santa Maria, Villa Clara province. Ecological indexes such as diversity (H') and equity (J') were estimated through a program named BIODIVERSITY Pro v2 and also the contents in the stomach of 341 specimens (25,81%) of the total was analyzed. The most abundant and distributed species in all the sampled sites was C. variegatus followed by G puncticulata. The number of fish of these species showed a differential gradient going from West to East: upward for C. variegatus and downward for G. puncticulata (X2 = 150,60, p< 0,001), being the latter the species that most equitably used the food resources (J' = 0,92) since it consumed 6 of them for food. These indigenous fish that are abundant in natural reservoirs should be taken into account for integrated control plans aimed at mosquito, gnat and horsefly breeding sites found in these locations.

  20. Bioaccumulation and toxicity of a cationic surfactant (DODMAC) in sediment dwelling freshwater invertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Comber, S.D.W. [Atkins Ltd, Chilbrook, Oasis Business Park, Eynsham, Oxford, OX29 4AH (United Kingdom)], E-mail: sean.comber@atkinsglobal.com; Rule, K.L. [Centre for Environmental Sciences, University of Southampton, Southampton SO17 1BJ (United Kingdom); Conrad, A.U. [Scottish Environmental Protection Agency, SEPA Corporate Office, Erskine Court Castle Business Park, Stirling FK9 4TR (United Kingdom); Hoess, S. [ECOSSA, Thierschstrasser 43, 80538 Muenchen (Germany); Webb, S.F. [Procter and Gamble, Temselaan 100, Strombeek-Bever B1853 (Belgium); Marshall, S. [Unilever Colworth, Sharnbrook, Bedford MK44 1LQ (United Kingdom)

    2008-05-15

    Dimethyldioctadecylammonium chloride (DODMAC, CAS No. 107-64-2) is the principal active component of Di(hydrogenated tallow alkyl) dimethylammonium chloride (DHTDMAC, CAS No. 61789-80-8), a cationic surfactant formerly used principally in laundry fabric softeners. After discharge to water, DODMAC partitions strongly to sediment, therefore the assessment of the effects of DODMAC to benthic organisms is essential in any risk assessment. Chronic toxicity studies were conducted with Lumbriculus variegatus (Oligochaete), Tubifex tubifex (Oligochaete) and Caenorhabditis elegans (Nematode). NOECs were greater than 5738, 1515 and 1351 mg/kg dw, respectively, even for sub-lethal effects. Measurement of the route of uptake of DODMAC by L. variegatus demonstrated the relative importance of uptake via ingestion (86%) compared with direct contact with the sediment and via pore water (14%). The overall tendency of DODMAC to bioaccumulate, however, was low with measured accumulation factors of 0.22 and 0.78 for L. variegatus and T. tubifex, respectively. - The cationic surfactant, DODMAC, exhibits low bioavailability and toxicity to sediment dwelling organisms, with uptake dominated by ingestion.