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1.
J Nematol ; 512019.
Artigo em Inglês | MEDLINE | ID: mdl-34179815

RESUMO

Three populations of Xiphinema non-americanum group species were detected in agricultural and natural ecosystems, during routine surveys for plant-parasitic nematodes in Spain. Based on morphological and molecular analyses, the species were identified as Xiphinema histriae and Xiphinema lapidosum, being this the first record and molecular characterization of both species in Spain. The morphometrics and morphology of the Spanish populations agree with those of the original description and paratype specimens and the present study provided a first description of the second to fourth juvenile stages of both species. A detailed study on the morphology in the Spanish populations of X. histriae, as well as in paratypes, showed a pseudo-Z-organ with weakly muscularized wall and containing numerous small dense granular bodies, which was different to the original description by Lamberti et al. (1993). This new finding suggests that X. histriae must be considered a member of the morphospecies Group 5 of X. non-americanum. Phylogenetic analysis based on D2 to D3 expansion segments of 28S gene, ITS1 and partial CoxI gene indicated that X. histriae and X. lapidosum are phylogenetically related with other Xiphinema non-americanum group spp. reported from Spain. Considering the pathological and economic importance of this group of nematodes, the combination of morphological characters, measurements, and molecular analysis is crucial for accurate identification of these species.

2.
J Nematol ; 50(1): 1-18, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30451425

RESUMO

Longidorids are economically important plant-parasitic nematodes because several species are virus vectors. Populations of Paralongidorus sali and Longidorus jonesi , isolated from woody perennials of Hangzhou, Zhejiang, China, were characterized molecularly and morphologically. The morphometric data of the Chinese populations of both species were compared with other populations. The present study provided a first record of the occurrence of Paralongidorus in China coupled with description of the first-stage Juvenile and male of L. jonesi . Phylogenetic analysis based on 18S and D2-D3 expansion segments of 28S gene indicated that L. jonesi clustered with L. jonesi reported from Japan and P. sali grouped with P. bikanerensis from Iran. Considering the pathological and economic importance of this group of nematodes, the study emphasized the need of updated descriptions from accurately identified specimens, isolation of sufficient material for examination, and molecular and phylogenetic analysis for a better understanding and diagnostics of Longidorid nematodes.

3.
Mar Environ Res ; 196: 106452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492324

RESUMO

A coastal predator-prey system, juvenile green crabs (Carcinus maenas) preying upon juvenile hard clams (Mercenaria mercenaria), was used to explore the link between crab predation rates and clam density and small-scale distribution patterns. The channel working area of a racetrack flume was adapted to form a sedimentary arena in a flowing seawater system (5 cm s-1) to assess crab predation rates in relation to clam density and distribution patterns (clams clustered in one patch vs two nearby vs two farther apart). The trials detected significant differences in relation to clam initial density and distribution with strong (∼50%) declines in clam mortality levels among spatial arrangements (one patch > two nearby > two farther apart). Feeding of clams was associated with the time taken by crabs to handle the first clam (first patch), and the frequency of three distinct types of crab behavior (eating, resting, and searching). Altogether these results suggest that small-scale changes in number and distribution of juvenile clams matter and may have unexpectedly strong effects on the outcome of predator-prey interactions.


Assuntos
Braquiúros , Mercenaria , Animais , Água do Mar , Comportamento Predatório
4.
Exp Parasitol ; 135(2): 240-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23876575

RESUMO

The current treatment and control of schistosomiasis, rely on a single drug, praziquantel, although, it has minor activity against juvenile stages of the parasite. Studies have shown that artemether (ART) exhibits effects against juveniles of Schistosoma mansoni Liberian and Puerto Rican strains, Schistosoma japonicum and Schistosoma haematobium. Aiming to assess the in vivo activity of single oral dose of ART against early juvenile stages of S. mansoni Egyptian strain, this study was established. Mice were treated with ART (400 mg/kg) at two time points evenly spaced over the period of larval development (7 and 21 days post-infection; pi), and a third treatment point (day 49 pi) was included to elucidate when susceptibility decreases. Administration of ART on day 7 pi reduced the total worm burden by 85.94%. The greatest reductions were seen when treatment was given on day 21 pi, with total and female worm burden reductions of 91.52% and 90.57%, respectively, and cessation of oviposition. Similar dose given on day 49 pi reduced total worm burden by 55.17% and female worm burden by 66.51%. Moreover, it induced significant reduction in the tissue egg load and significant alterations in the oogram pattern with decreased immature eggs and increased dead eggs. Antipathological activities were evident in significant reductions in granulomata count and diameter. In conclusion, ART exhibits major in vivo schistosomicidal effects against the early larval migratory stages of S. mansoni Egyptian strain, mainly the 21-day old schistosomula, hence preventing disease progression and morbidity.


Assuntos
Artemisininas/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Esquistossomicidas/farmacologia , Administração Oral , Animais , Artemeter , Biomphalaria , Feminino , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Schistosoma mansoni/crescimento & desenvolvimento , Esquistossomose mansoni/patologia
5.
Microorganisms ; 11(2)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36838431

RESUMO

Spittlebugs are xylem-sap feeding insects that can exploit a nutrient-poor diet, thanks to mutualistic endosymbionts residing in various organs of their body. Although obligate symbioses in some spittlebug species have been quite well studied, little is known about their facultative endosymbionts, especially those inhabiting the gut. Recently, the role played by spittlebugs as vectors of the phytopathogenetic bacterium Xylella fastidiosa aroused attention to this insect group, boosting investigations aimed at developing effective yet sustainable control strategies. Since spittlebug nymphs are currently the main target of applied control, the composition of gut bacterial community of the juveniles of Philaenus spumarius and Lepyronia coleoptrata was investigated using molecular techniques. Moreover, bacteria associated with their froth, sampled from different host plants, were studied. Results revealed that Sodalis and Rickettsia bacteria are the predominant taxa in the gut of P. spumarius and L. coleoptrata nymphs, respectively, while Rhodococcus was found in both species. Our investigations also highlighted the presence of recurring bacteria in the froth. Furthermore, the foam hosted several bacterial species depending on the host plant, the insect species, or on soil contaminant. Overall, first findings showed that nymphs harbor a large and diverse bacterial community in their gut and froth, providing new accounts to the knowledge on facultative symbionts of spittlebugs.

6.
Zootaxa ; 4524(3): 359-391, 2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30486114

RESUMO

 The genus Monastria Saussure, 1864 includes medium to large sized (40-55 mm) dark brown or black cockroaches found in the understory of the Neotropical Atlantic Forest from the Northeast of Brazil to Paraguay and Argentina. The genus shows evident sexual dimorphism: males are elongated with fully developed wings extending beyond the apex of cerci and females are oval and brachypterous. This study is a revision of the genus with redescription of the three already known species, Monastria biguttata (Thunberg, 1826), Monastria similis (Serville, 1838) and Monastria angulata Saussure, 1864, and description of five new ones, Monastria itubera sp. n. and Monastria itabuna sp. n. from state of Bahia, Monastria cabocla sp. n. from state of Sergipe, Monastria kaingangue sp. n. from state of São Paulo and Monastria sagittata sp. n. from state of Minas Gerais. The morphology of the genus and all species is described in details, including male genitalia. Based on this revision, we proposed a new combination for Hiereoblatta papillosa (Thunberg, 1826) comb. n., excluding it from the genus Monastria. For the first time, the juvenile stages of Monastria are characterized and compared to other genera of Blaberinae of the Atlantic forest. Three determination keys are provided. The two first are aimed at identifying the adults and juvenile stages of the five genera of the Blaberinae radiation endemic to the Atlantic forest, respectively. The third concerns the identification of the species of the genus Monastria. A map indicating the localities where species were sampled is also provided.


Assuntos
Baratas , Florestas , Animais , Argentina , Brasil , Feminino , Masculino , Paraguai
7.
Zookeys ; (667): 1-19, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769632

RESUMO

Longidorus piceicola, a new geographical and host record from Romania, was described and illustrated on the basis of two populations originating from a coniferous and a deciduous forest. The main morphological characters of specimens from Romania correspond very well with the type material collected from the soil around Picea abies L. (Slovakia) except for the shorter body and tail. The D2-D3 fragment of 28S rDNA from both populations was amplified and sequenced, and the sequences were identical to L. piceicola sequence from Slovakia. The partial 18S-ITS1-5.8S-ITS2 rDNA regions from one of the populations were sequenced for the first time. The evolutionary relationships between L. piceicola and the closest species L. intermedius based on D2-D3 sequence divergence and single-nucleotide polymorphisms are discussed. Although having very low sequence dissimilarity (0.3-0.9 %) both species have distinct morphology and biology. Longidorus piceicola differs from L. intermedius in having a much longer odontostyle, body, distance anterior end - guide ring, a wider lip region, more ventromedian supplements (11 vs 5-7) in the male, and develops through four rather than three juvenile stages. Furthermore, L. piceicola occurs more frequently in association with conifers, while L. intermedius is found mainly in oak forests.

8.
Acta sci., Biol. sci ; Acta sci., Biol. sci;42: e47522, fev. 2020. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460928

RESUMO

Two isolations of fungi from a bank of microorganisms in the Biological Sciences Laboratory at Escuela Superior Politécnica de Chimborazo were tested on the galling caused by Meloidogyne incognita in tomato seedlings grown in pots with substrate infested with a suspension of nematodes, with approximately 2000 juvenile stages (J2) from root galls of plants infested with M. incognita, taken from the Nematology laboratory of the Ecuadorian Agricultural Quality Assurance Agency (AGROCALIDAD). Pleurotus ostreatus was a fungus with nematicidal characteristics through production of toxins; while Trichoderma harzianum is a widely known fungus, although it is a plant growth promoter rather than a nematicide. The two fungi were formulated in wheat straw and rabbit manure. A complete randomized design (CRD) with three replications was used, with a chemical control (Fenamiphos) and an absolute control. Five grams of each formulation was applied per plant before the transplant. The number of galls in the roots, plant height, stem diameter, number of leaves and fresh and dry weight of the aerial part and roots of 180 tomato plants grown in greenhouse were evaluated at 60 days after transplant. The results showed that the two fungi reduced the number of galls and made it possible to obtain dry weights of the aerial and radicular part very close to the chemical control (10.09 and 3.39 g) with 8.68; 8.04; 2.96 and 3.25 g respectively. Besides Trichoderma harzianum proved to be a good promoter of root growth, therefore, the use of these bioformulates is a promising measure for the control of this phytonematode


Assuntos
Solanum lycopersicum , Pleurotus , Trichoderma , Tylenchoidea
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