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1.
Semina cienc. biol. saude ; 45(2): 91-100, jul./dez. 2024. ilus; tab.
Artículo en Inglés | LILACS | ID: biblio-1562705

RESUMEN

This study constitutes the first record of parasitism and associations between bat flies ectoparasite of the Streblidae family and bats (Chiroptera: Phyllostomidae) in the São Francisco Forest State Park (SFFSP). The bats were captured using mist nets set up at various points along the park's visitor trail. Following collection, the bats were inspected for ectoparasites, which when found were collected with metal tweezers and stored in vials with 70% alcohol to be identified later. The captured bats were subjected to morphometrics so that the information obtained could help identify which bat species was the host of the ectoparasite collected and then they were released. A total of 36 dipterans from the Streblidae family belonging to six species from four genera: Aspidoptera falcata Wenzel, 1976; Aspidoptera phyllostomatis (Perty, 1833); Megistopoda aranea (Coquillett, 1899); Megistopoda proxima (Séguy, 1926); Paratrichobius longicrus (Miranda Ribeiro, 1907) and Trichobius joblingiWenzel, 1966, infesting phyllostomids of four species: Artibeus lituratus (Olfers, 1818); Artibeus planirostris (Spix, 1823); Carollia perspicillata (Linneaus, 1758) and Sturnira lilium (E. Geoffroy, 1810). The most abundant species were Trichobius joblingi (38.89%) and Aspidoptera phyllostomatis(27.78%).


Este estudo constitui o primeiro registro de parasitismo e associações entre moscas ectoparasitas de morcegos da família Streblidae e morcegos (Chiroptera: Phyllostomidae) no Parque Estadual Floresta São Francisco (PEFSF). Os morcegos foram capturados usando redes de neblina instaladas em vários pontos ao longo da trilha de visitantes do parque. Após a coleta, os morcegos foram inspecionados em busca de ectoparasitas, que, quando encontrados, eram coletados com pinças metálicas e armazenados em frascos com álcool 70% para serem identificados posteriormente. Os morcegos capturados foram submetidos à morfometria para que as informações obtidas pudessem ajudar a identificar qual espécie de morcego era a hospedeira do ectoparasita coletado e, em seguida, foram liberados. Um total de 36 dípteros de Streblidae foram coletados, pertencentes a seis espécies de quatro gêneros: Aspidoptera falcata Wenzel, 1976; Aspidoptera phyllostomatis (Perty, 1833); Megistopoda aranea (Coquillett, 1899); Megistopoda proxima (Séguy, 1926); Paratrichobius longicrus (Miranda Ribeiro, 1907) e Trichobius joblingi Wenzel, 1966, infestando filostomídeos de quatro espécies: Artibeus lituratus(Olfers, 1818); Artibeus planirostris (Spix, 1823); Carollia perspicillata (Linneaus, 1758) e Sturnira lilium (E. Geoffroy, 1810). As espécies mais abundantes foram Trichobius joblingi (38,89%) e Aspidoptera phyllostomatis (27,78%).


Asunto(s)
Animales
2.
Plant Dis ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39254849

RESUMEN

A unique cyst nematode population (Heterodera spp.) was collected from rice roots in Luoding County, Guangdong Province, China. Morphological and molecular analyses revealed it is significantly different from all previously described cyst nematode species. It is described as Heterodera luodingensis n. sp. and classified in the Cyperi group. H. luodingensis n. sp. is characterized by its lemon-shaped cyst with a prominent terminal vulval cone that is ambifenestrate with abundant bullae and a relatively short vulval slit, 31.3 (24.4 -38.7) µm long. The second-stage juveniles (J2) are characterized by dumbbell shaped labials, three lip annules and a lateral field with three incisures. The J2 stylet is 18.7 (16.9 -19.8) µm long with anterior concave or spherical knobs. The tail is elongate conoid, tapering to a rounded terminus or zig tapering to a rounded terminus that is 54.9 (43.9 - 64.3) µm long with a hyaline region comprising 40.3%-52.5% of the tail. Phylogenetic tree analysis based on rDNA 28S D2D3 and ITS fragments showed that the H. luodingensis n. sp. is unique and clearly separated it from other cyst nematodes. It is most closely related to H. oryzicola, H. fengi, H. elachista, H. oryzae, and H. guangdongensis. H. luodingensis n. sp. can be distinguished from H. oryzicola by its shorter vulval slit and underbridge, from H. elachista by abundant bullae, shorter vulval slit and fenestrate width, from H. oryzae by a shorter vulval slit and underbridge, from H. fengi by a shorter vulval slit, from H. guangdongensis by a longer cyst length and abundant bulla. Based on PCR-RFLP of rDNA-ITS, H. luodingensis n. sp. can be clearly distinguished from H. oryzicola, H. mothi, H. elachista, H. guangdongensis and H. cyperi. A parasitism test from a pure culture derived from a single cyst in greenhouse showed that H. luodingensis n. sp. can successfully complete its life cycle on rice and rice is its type host.

3.
Front Vet Sci ; 11: 1435395, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39286596

RESUMEN

This review article describes the roles of ultrasound in assessing thoracic and abdominal infectious diseases, mainly bacterial and parasitic ones that affect farm animals, including cattle, camels, sheep, and goats. Ultrasonography is a non-invasive imaging technique used to diagnose infectious diseases affecting the cardiovascular, respiratory, digestive, urinary, and hepatobiliary systems. In cases of thoracic and abdominal infections, ultrasound typically reveals abnormalities in echogenicity and echotexture, the presence of unusual artifacts, and mass formation exerting pressure on surrounding structures. Inflammatory and degenerative changes within the viscera can be identified ultrasonographically by comparing the echogenicity of affected areas with that of the surrounding normal parenchyma, such as in fascioliasis. Bacterial and parasitic infections often result in capsular mass lesions with anechoic contents, as observed in hydatid cysts and cysticercosis, or varying echogenic contents, as observed in liver abscesses. Effusions within the pericardium, pleura, and peritoneum are common ultrasonographic findings in infectious thoracic and abdominal diseases. However, these effusions' echogenicity does not always allow for clear differentiation between transudates and exudates. The routine use of ultrasonography in the evaluation of the chest and abdomen in affected or suspected ruminants is highly beneficial for detection, guiding therapeutic decisions, assessing prognosis, and aiding in the eradication of highly contagious diseases that cause significant economic losses.

4.
J Helminthol ; 98: e51, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291544

RESUMEN

Rhabdias are lung-dwelling parasites of anurans and some reptiles. Currently, 93 species are known to exist worldwide. The identification of Rhabdias species is based mainly on morphological traits of hermaphroditic females that generally have a very conserved morphology. However, different approaches, such as the combination of morphological, molecular, and ecological data, have provided advances in identifying and delimiting rhabdiasid species. Here, we describe a new species of Rhabdias from the south of Brazil, with morphological and molecular data. The new species is distinguished from its congeners by having an elongated body, evident cephalic dilation, larger buccal capsule, and large esophagus. In addition to morphological characteristics, we observed significant genetic divergence among the cytochrome oxidase subunit I (COI) sequence of the new species and the closest available sequence, Rhabdias fuelleborni (10.24%-10.87%). Furthermore, phylogenetic reconstructions based on the COI gene indicated that the new species represents a different lineage, constituting an outgroup of the species complexes Rhabdias cf. stenocephala and Rhabdias fuelleborni with Rhabdias sp. 4. Thus, Rhabdias megacephala is the 24th nominal species of the Neotropical region, the 14th Brazilian, and the fourth species described from south of Brazil.


Asunto(s)
Anuros , Complejo IV de Transporte de Electrones , Bosques , Filogenia , Animales , Brasil , Femenino , Anuros/parasitología , Complejo IV de Transporte de Electrones/genética , Masculino , Infecciones por Rhabditida/parasitología , Infecciones por Rhabditida/veterinaria , Rhabdiasoidea/genética , Rhabdiasoidea/clasificación , Rhabdiasoidea/anatomía & histología , Rhabdiasoidea/aislamiento & purificación
5.
Int J Parasitol Parasites Wildl ; 25: 100979, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39297147

RESUMEN

The phenomenon of cuckoos' brood parasitism is well known and can be investigated using applied mathematical techniques. Among adaptive features of this phenomenon are certain egg parameters that ensure their shortened incubation period (I) and thus the successful survival of their offspring. In particular, the volume of a cuckoo egg is not less than, or exceeds, that of the host species, which should, in theory, increase I. Also, cuckoo eggs have thicker shell than that of nest hosts. Here, we analyzed the available geometric dimensions of eggs in 447 species and found an inverse correlation (-0.585, p < 0.05) between I and the shell thickness-to-egg surface area ratio (T/S). A mathematical relationship was derived to calculate I depending on T/S. This premise was confirmed by comparative calculations using egg images of two parasitic species, common (Cuculus canorus) and plaintive cuckoo (Cacomantis merulinus) and their hosts: great reed warbler (Acrocephalus arundinaceus), European robin (Erithacus rubecula), rufescent prinia (Prinia rufescens), and common tailorbird (Orthotomus sutorius). An average calculated I value for cuckoo eggs was one day less than that for host eggs. Our findings unravel additional details of how cuckoos adapt to brood parasitism and specific host-parasite relationships.

6.
Plant Cell Physiol ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39275795

RESUMEN

Many root parasitic plants in the Orobanchaceae use host-derived strigolactones as germination cues. This adaptation facilitates attachment to a host and is particularly important for the success of obligate parasitic weeds that cause substantial crop losses globally. Parasite seeds sense strigolactones through "divergent" KARRIKIN INSENSITIVE2 (KAI2d)/HYPOSENSITIVE TO LIGHT (HTL) α/ß-hydrolases that have undergone substantial duplication and diversification in Orobanchaceae genomes. After germination, chemotropic growth of parasite roots toward a strigolactone source also occurs in some species. We investigated which of the seven KAI2d genes found in a facultative hemiparasite, Phtheirospermum japonicum, may enable chemotropic responses to strigolactones. To do so, we developed a triple mutant Nbd14a,b kai2i line of Nicotiana benthamiana in which strigolactone-induced degradation of SMAX1, an immediate downstream target of KAI2 signaling, is disrupted. In combination with a transiently expressed, ratiometric reporter of SMAX1 protein abundance, this mutant forms a system for the functional analysis of parasite KAI2d proteins in a plant cellular context. Using this system, we unexpectedly found three PjKAI2d proteins that do not trigger SMAX1 degradation in the presence of strigolactones. Instead, these PjKAI2d inhibit the perception of low strigolactone concentrations by strigolactone-responsive PjKAI2d in a dominant-negative manner that depends upon an active catalytic triad. Similar dominant-negative KAI2d paralogs were identified in an obligate hemiparasitic weed, Striga hermonthica. These proteins suggest a mechanism for attenuating strigolactone signaling in parasites, which might be used to enhance the perception of shallow strigolactone gradients during root growth toward a host or to restrict germination responses to specific strigolactones.

7.
J Invertebr Pathol ; 207: 108211, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39343127

RESUMEN

Acanthocephalan parasites, specifically from the genus Profilicollis, are known to infect decapod crustaceans, including mole crabs like Emerita brasiliensis, which serve as intermediate hosts in their complex life cycles. This study reports the first occurrence of the acanthocephalan parasite Profilicollis altmani infecting the mole crab Emerita brasiliensis on a sandy beach in southeastern Brazil, thereby expanding the known geographic range of this parasite. Additionally, the study provides novel molecular data that enhance our understanding of the parasite's taxonomy and distribution, including the first evidence of genetic variation within populations of the intermediate host E. brasiliensis. Phylogenetic analysis based on mitochondrial COX1 gene sequences confirmed the identification of the parasite and underlined small genetic differences among P. altmani populations. These findings suggest a weak genetic population structure of the parasite and underscore the need for further studies to understand gene flow among these populations. This work contributes to the knowledge of parasite-host interactions in sandy beach ecosystems. It highlights the importance of monitoring parasitic infections in species like E. brasiliensis, which play a crucial ecological role in these environments.

8.
Acta Trop ; 259: 107375, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39226993

RESUMEN

Blood feeding ectoparasites of bats have been found to contain insect-specific and vertebrate-infecting viruses of agricultural and medical importance. While it is plausible that some of these are of bat origin, those would be sourced either from the bat exterior or their blood meal. Bats, in addition to their regular diets, consume numerous ectoparasites during grooming. All microbes on and in the ectoparasites would then be introduced into the bat gut upon ingestion of the ectoparasites. To investigate the potential impact of bat ectoparasite viromes on the gut viral microbiome of bats, we compared virus sequences from bats and their blood feeding ectoparasites collected from Yunnan Province, China. Although all the co-occurring viruses were bacteriophages, we observed that bats contained a larger set of viruses than their ectoparasites, and that the set of predicted viruses present in the bats were more diverse than those present in bat ectoparasites. Our analysis suggests that despite a heavy influx of ectoparasites into the digestive tract of bats through consumption, there are only few co-occurring/shared viruses between bats and their ectoparasites, and that these ectoparasites may not be a major driver of bat virome diversity. Our findings provide necessary preliminary data for the evaluation of bat ectoparasites as a potential source of bat infecting viruses.


Asunto(s)
Artrópodos , Quirópteros , Viroma , Animales , Quirópteros/virología , Quirópteros/parasitología , China , Infestaciones Ectoparasitarias/veterinaria , Infestaciones Ectoparasitarias/parasitología , Virus/clasificación , Virus/aislamiento & purificación , Virus/genética
9.
Biol Lett ; 20(9): 20240411, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39317329

RESUMEN

As the avian embryo grows and develops within the egg, its metabolic rate gradually increases. Obligate avian brood-parasitic birds lay their eggs in the nests of other species to avoid the costs of parental care, and all but one of these brood-parasitic species are altricial at hatching. Yet the chicks of some altricial brood-parasitic species perform the physically demanding task of evicting, stabbing or otherwise killing host progeny within days of hatching. This implies a need for high metabolic rates in the embryo, just as precocial species require. Using flow-through respirometry in situ, we investigated embryonic metabolic rates in diverse avian brood parasite lineages which either kill host offspring (high virulence) or share the nest with host young (low virulence). High-virulence brood parasite embryos exhibited higher overall metabolic rates than both non-parasitic (parental) species and low-virulence parasites. This was driven by significantly elevated metabolic rates around the halfway point of incubation. Additionally, a fine-scale analysis of the embryos of a host-parasitic pair showed faster increases in metabolic rates in the parasite. Together these results suggest that the metabolic patterns of the embryos of high-virulence parasites facilitate their early-life demands.


Asunto(s)
Aves , Interacciones Huésped-Parásitos , Animales , Aves/parasitología , Aves/embriología , Embrión no Mamífero/metabolismo , Virulencia , Comportamiento de Nidificación , Metabolismo Energético
10.
Infect Immun ; : e0028424, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324805

RESUMEN

Orientia tsutsugamushi a causal agent of scrub typhus, is an obligate intracellular bacterium that, akin to other rickettsiae, is dependent on host cell-derived nutrients for survival and thus pathogenesis. Based on limited experimental evidence and genome-based in silico predictions, O. tsutsugamushi is hypothesized to parasitize host central carbon metabolism (CCM). Here, we (re-)evaluated O. tsutsugamushi dependency on host cell CCM as initiated by glucose and glutamine. Orientia infection had no effect on host glucose and glutamine consumption or lactate accumulation, indicating no change in overall flux through CCM. However, host cell mitochondrial activity and ATP levels were reduced during infection and correspond with lower intracellular glutamine and glutamate pools. To further probe the essentiality of host CCM in O. tsutsugamushi proliferation, we developed a minimal medium for host cell cultivation and paired it with chemical inhibitors to restrict the intermediates and processes related to glucose and glutamine metabolism. These conditions failed to negatively impact O. tsutsugamushi intracellular growth, suggesting the bacterium is adept at scavenging from host CCM. Accordingly, untargeted metabolomics was utilized to evaluate minor changes in host CCM metabolic intermediates across O. tsutsugamushi infection and revealed that pathogen proliferation corresponds with reductions in critical CCM building blocks, including amino acids and TCA cycle intermediates, as well as increases in lipid catabolism. This study directly correlates O. tsutsugamushi proliferation to alterations in host CCM and identifies metabolic intermediates that are likely critical for pathogen fitness.IMPORTANCEObligate intracellular bacterial pathogens have evolved strategies to reside and proliferate within the eukaryotic intracellular environment. At the crux of this parasitism is the balance between host and pathogen metabolic requirements. The physiological basis driving O. tsutsugamushi dependency on its mammalian host remains undefined. By evaluating alterations in host metabolism during O. tsutsugamushi proliferation, we discovered that bacterial growth is independent of the host's nutritional environment but appears dependent on host gluconeogenic substrates, including amino acids. Given that O. tsutsugamushi replication is essential for its virulence, this study provides experimental evidence for the first time in the post-genomic era of metabolic intermediates potentially parasitized by a scrub typhus agent.

11.
Insects ; 15(9)2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39336658

RESUMEN

Fungi belonging to the genus Trichoderma have received high consideration in agriculture due to their beneficial effects on crops from their plant promotion effects and protection from disease. A role of Trichoderma fungi in triggering plant defense mechanisms against insect pests, either directly or by natural enemy attraction, has been proposed, even if the results in different studies are controversial. In this present study, using zucchini plants as a model species, we investigated the effects of Trichoderma afroharzianum strain T22 plant inoculation on the cotton aphid Aphis gossypii and its endoparasitoid Aphidius colemani. Our results showed that the inoculation with T. afroharzianum T22 promotes A. gossypii population growth and makes zucchini more attractive to the aphid. The higher abundance of aphids on Trichoderma-inoculated zucchini was compensated for by a higher presence of the mummies of Aphidius colemani. In this present study, we recorded a higher zucchini biomass, thereby confirming that Trichoderma can act as a plant growth inducer.

12.
Insects ; 15(9)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39336690

RESUMEN

Chouioia cunea are known to exploit in varying degrees a wide range of lepidopteran species and its offspring development may vary with host species. This study examined its preimaginal development and larval gut microbiota in parasitizing five folivorous lepidopteran hosts including Hyphantria cunea (referred to thereafter as CcHc), Antherea pernyi (CcAp), Helicoverpa armigera (CcHa), Spodoptera exigua (CcSe), and Spodoptera frugiperda (CcSf). Though rates of parasitism and offspring eclosion did not change with host species, the development period and number of offspring eclosed varied with hosts, with the shortest period in CcSf and the highest number from CcAp. For offspring larval gut microbiota, though phylum Proteobacteria was dominant for attacking CcAp, Firmicutes was so for the other hosts. All microbial genera except Enterococcus were less abundant for CcSf than the other hosts. The database-based predictions indicate a significant positive correlation between Cutibacterium and Aureimonas with the relative number of wasp emergence, while Blastomonas exhibits a strong positive association with the developmental period. Our results imply the potential relevance of the gut microbial community in offspring larvae to host species attacked by C. cunea.

13.
mBio ; : e0058324, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39194186

RESUMEN

Infection outcomes can be strongly context dependent, shifting a host-symbiont relationship along a parasitism-mutualism continuum. Numerous studies show that under stressful conditions, symbionts that are typically mutualistic can become parasitic. The reverse possibility, a parasite becoming mutualistic, has received much less study. We investigated whether the parasitic microsporidium Ordospora pajunii can become beneficial for its host Daphnia dentifera in the presence of the more virulent fungal pathogen Metschnikowia bicuspidata. We found that, even though infection with O. pajunii reduces the frequency of penetration of M. bicuspidata spores into the host body cavity, it does not improve the survival or reproduction of the host; conversely, coinfection increased the mortality of Daphnia. This shorter lifespan of coinfected hosts disrupted the life cycle of M. bicuspidata, greatly reducing its fitness. Thus, coinfection with both pathogens was detrimental to the host at the individual level but might be beneficial for the host population as a result of greatly reduced production of M. bicuspidata spores. If so, this would mean that O. pajunii outbreaks should delay or prevent M. bicuspidata outbreaks. In support of this, in an analysis of dynamics of naturally occurring outbreaks in two lakes where these pathogens co-occur, we found a time lag in occurrence between O. pajunii and M. bicuspidata, with M. bicuspidata epidemics only occurring after the collapse of O. pajunii epidemics. Thus, these results suggest that the interaction between co-occurring symbionts, and the net impact of a symbiont on a host, might be qualitatively different at different scales.IMPORTANCEUnderstanding the factors that modify infection probability and virulence is crucial for identifying the drivers of infection outbreaks and modeling disease epidemic progression, and increases our ability to control diseases and reduce the harm they cause. One factor that can strongly influence infection probability and virulence is the presence of other pathogens. However, while coexposures and coinfections are incredibly common, we still have only a limited understanding of how pathogen interactions alter infection outcomes or whether their impacts are scale dependent. We used a system of one host and two pathogens to show that sequential coinfection can have a tremendous impact on the host and the infecting pathogens and that the outcome of (co-)infection can be negative or positive depending on the focal organization level.

14.
Ann Bot ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39213003

RESUMEN

BACKGROUND AND AIMS: Biological aspects of haustorial parasitism have significant effects on the configuration of the plastid genome. Approximately half the diversity of haustorial parasites belongs to the order Santalales, where a clearer picture of plastome evolution in relation to parasitism is starting to emerge. However, in previous studies of plastome evolution there is still a notable under-representation of members from non-parasitic and deep-branching hemiparasitic lineages, limiting evolutionary inference around the time of transition to a parasitic lifestyle. To expand taxon sampling relevant to this transition we therefore targeted three families of non-parasites (Erythropalaceae, Strombosiaceae, and Coulaceae), two families of root-feeding hemiparasites (Ximeniaceae and Olacaceae), and two families of uncertain parasitic status (Aptandraceae and Octoknemaceae). With data from these lineages we aimed to explore plastome evolution in relation to evolution of parasitism. METHODS: From 29 new samples we sequenced and annotated plastomes and the nuclear ribosomal cistron. We examined phylogenetic patterns, plastome evolution, and patterns of relaxed or intensified selection in plastid genes. Available transcriptome data were analyzed to investigate potential transfer of infA to the nuclear genome. RESULTS: Phylogenetic relationships indicate a single functional loss of all plastid ndh genes (ndhA-K) in a clade formed by confirmed parasites and Aptandraceae, and the loss coincides with major size and boundary shifts of the inverted repeat (IR) region. Depending on an autotrophic or heterotrophic lifestyle in Aptandraceae, plastome changes are either correlated with or predate evolution of parasitism. Phylogenetic patterns also indicate repeated loss of infA from the plastome, and based on presence of transcribed sequences with presequences corresponding to thylakoid luminal transit peptides, we infer that the genes were transferred to the nuclear genome. CONCLUSIONS: Except for the loss of the ndh complex, relatively few genes have been lost from the plastome in deep-branching root parasites in Santalales. Prior to loss of the ndh genes, they show signs of relaxed selection indicative of their dispensability. To firmly establish a potential correlation between ndh gene loss, plastome instability and evolution of parasitism, it is pertinent to refute or confirm a parasitic lifestyle all Santalales clades.

15.
Ecol Evol ; 14(8): e70117, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091329

RESUMEN

The Diederik cuckoo, Chrysococcyx caprius, is a small Afrotropical bird in the family Cuculidae. It is taxonomically related to 13 other species within the genus Chrysococcyx and is migratory in sub-Saharan Africa. It has a unique breeding behaviour of being a brood parasite: Breeding pairs lay their eggs in the nests of a host species and hatchlings expel the eggs of the host species. The aim of the present study was to investigate diversity in two circadian clock genes, Clock and Adcyap1, to probe for a relationship between genetic polymorphisms and their role in circannual timing and habitat selection (phenology) in intra-African migrants. DNA extracted from blood was used for the PCR amplification and sequencing of clock genes in 30 Diederik cuckoos. Three alleles were detected for Clock with similar genotypes between individuals from the Northern and Southern breeding ranges while 10 alleles were detected for Adcyap1, having shorter alleles in the North and longer alleles in the South. Population genetic analyses, including allele frequency and zygosity analysis, showed distinctly higher frequencies for the most abundant Clock allele, containing 10 polyglutamine repeats, as well as a high degree of homozygosity. In contrast, all individuals were heterozygous for Adcyap1 and alleles from both regions showed distinct differences in abundance. Comparisons between both clock genes and phenology found several phenotypic correlations. This included evidence of a relationship between the shorter alleles and habitat selection as well as a relationship between longer alleles and timing. In both instances, evidence is provided that these effects may be sex-specific. Given that these genes drive some of the synchronicity between environments and the life cycles of birds, they provide valuable insight into the fitness of species facing global challenges including climate change, urbanisation and expanding agricultural practices.

16.
J Chem Ecol ; 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39095554

RESUMEN

Parasitoid biological control agents rely heavily on olfaction to locate their hosts. Chemical cues associated with hosts and non-hosts are known to influence the expression of host preferences and host-specificity. A better understanding of how and why parasitoids attack some species and not others, based on volatile organic compounds associated with potential hosts, can provide key information on the parasitoid's host preferences, which could be applied to pre-release risk assessments for classical biological control agents. Electrophysiological techniques such as electroantennography (EAG) and GC-EAD (gas chromatography coupled with electroantennographic detection) are widely used to identify bioactive semiochemicals. But the application of these techniques to understanding how chemical ecological cues mediate parasitoid host specificity has not been as thoroughly explored. We conducted GC-EAD and EAG studies to identify olfactory-active compounds associated with adult females of nine stink bug species from Aotearoa/New Zealand on the antennae of three closely related parasitoid species: Trissolcus japonicus Ashmead, a pre-emptively (= proactively) approved biocontrol agent against brown marmorated stink bug; T. basalis (Wollaston), a biocontrol agent introduced against Nezara viridula L. in 1949; and T. oenone Johnson, a native Australasian pentatomid parasitoid. Eight compounds associated with stink bugs elicited antennal responses from all three parasitoids, and we were able to identify seven of these. (E)-2-hexenal, (E)-4-oxo-2-hexenal, (E)-2-octenal and (E)-2-decenal generally elicited stronger responses in the three parasitoids, while n-tridecane, n-dodecane, and (E)-2-decenyl acetate elicited weaker responses. We discuss how and why the results from electrophysiological experiments can be applied to non-target risk assessments within biological control programmes.

17.
Ecol Evol ; 14(8): e70190, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39165540

RESUMEN

Social monogamy is the prevalent mating system in birds, but alternative strategies of extra-pair paternity (EPP) and conspecific brood parasitism (CBP) occur in many species. Raptors are virtually absent in discussions of broad taxonomic reviews regarding EPP and CBP likely because these strategies are mostly absent or at low frequency; CBP is unreported in solitary nesting raptors. In contrast, we found high frequencies of EPP (16%-31%) and CBP (15%-26%) nests among three populations of Cooper's Hawks (Accipiter cooperii) across the northern breeding range of this solitary nesting, socially monogamous species. EPP and CBP combined occurred in 42%-46% of all nests among populations and hence unexpectedly were nearly equivalent to proportions of genetically monogamous nests. Select covariates failed to predict presence of EPP and CBP in part because virtually all extra-pair adults were uncaught and likely were floaters. We found no support for the hypothesis that territorial females traded copulations for food to maximize energy intake for increased production. Our unique discoveries enhance knowledge of the extent and diversity of alternative breeding strategies among groups of avian and other animal species.

18.
Int Microbiol ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39122800

RESUMEN

Dry bean (Phaseolus vulgaris L.) is an important commercialized field crop in South Africa for aiding in food security as a cheap protein source. However, it is highly susceptible to root-knot nematodes (RKN), Meloidogyne species. Use of indigenous nematophagous fungi as bio-control agents (BCA) of Meloidogyne nematodes is a promising research focus area. This is because indigenous fungal species are naturally part of the ecosystem and therefore compatible with other biological processes unlike most synthetic chemicals. The objective of the study was to identify indigenous nematophagous fungal BCA and establish their potential efficacy in reducing M. enterolobii population densities on dry bean with and without incorporation of compost. Screened indigenous fungal species included Aspergillus terreus, Talaromyces minioluteus, T. sayulitensis, Trichoderma ghanense, and T. viride. There were observed significant parasitism differences (P ≤ 0.05) among the BCA, with T. ghanense showing the highest egg parasitism (86%), followed by T. minioluteus (72%) and T. sayulitensis (70%). On the other hand, the highest J2 parasitism was observed on T. minioluteus (95%), followed by A. terreus and T. viride (63%). A similar trend was observed under in vivo conditions, with higher efficacy with compost incorporation. This provides a highly encouraging alternative and ecologically complementary Meloidogyne management in dry bean production.

19.
Front Plant Sci ; 15: 1372529, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39119505

RESUMEN

Cuscuta chinensis have a significant regulatory effect on plant growth, but the response mechanism of functional traits to the parasitism of C. chinensis and the trade-off relationship between traits and hyperspectral characteristics are not clear. We investigated the functional trait response and hyperspectral characteristics of Euonymus japonicus, the most common urban hedge plant in China, to the parasitism of C. chinensis. The results showed that the parasitism of C. chinensis led to the difference of leaf functional traits: the leaf thickness, stomatal density, and leaf dry matter content were significantly increased, whereas the leaf area, leaf weight, specific leaf area, chlorophyll content index, and leaf tissue density were significantly decreased. Notably, the parasitism of C. chinensis changed the spatial distribution pattern of stomata and promoted the stomata to be evenly distributed. Furthermore, the spectral reflectance of leaves treated with the parasitism of C. chinensis tended to increase. The parasitism of C. chinensis led to the "blue shift" of hyperspectral reflectance of leaves. There was a significant correlation between spectral parameters and leaf functional traits, and leaf biomass accounted for 83% of the variation in reflectance of the water stress band. In general, the parasitism of C. chinensis determines the strategic way of plant utilization of resources and affects the change of plant strategy by affecting the difference of traits. Urban plants were more inclined to invest resources in nutrient storage capacity at the expense of resources investment in photosynthetic capacity and defense mechanism. The plant ecological strategy changed from resource acquisition to resource conservation. This finding comes up with a new strategy that urban tree species can modify the plasticity of functional traits for survival and growth under the interference of parasitic plants.

20.
Curr Zool ; 70(4): 539-547, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39176069

RESUMEN

The shiny cowbird Molothrus bonariensis parasitizes many species with different life-history traits and has a detrimental effect on the survival of the progeny of the hosts. In response, hosts have developed numerous antiparasitic defenses. Here, we examined the effects of brood parasitism by shiny cowbird on the clutch and brood sizes (83 nests) in a small host, the black-backed water tyrant Fluvicola albiventer. We also studied whether the death of parasite nestlings was related to the care of the foster parents and whether the host had any antiparasitic defense against the shiny cowbird. Our results indicate that brood parasitism significantly decreased the host hatching and fledging successes. The majority of nest failures (57%) were caused by brood parasitism. Shiny cowbird parasitism occurred in 52% of nests and the intensity of parasitism was 1.23 ± 0.53 eggs per parasitized nest. Of the total host eggs, 54% were damaged. During the incubation stage, 20 nests (47%) were abandoned because of egg punctures by shiny cowbirds females. Only two parasitic fledglings were recorded, while the remaining nestlings either died from starvation (n = 12) or predation (n = 3). Foster parents abandoned parasitic nestlings between 5 and 10 days old. Our findings demonstrate that the shiny cowbird has very low rates of fledging success when parasitizing black-backed water tyrant. Also, parasitism had a high reproductive cost in the black-backed water tyrant because a very low proportion (7%) of the parasitized nests (n = 43) were successful.

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