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1.
PLoS One ; 19(3): e0298530, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512935

RESUMO

Monitoring is necessary for the management of any threatened species if its predicament and status are to improve. Monitoring establishes baseline data for tracking trends in distribution and abundance and is a key tool for informing threatened species management. Across much of the Old World, bats in the genus Pteropus (Pteropodidae, Chiroptera) face significant threats from habitat loss, conflict with humans, and hunting. Despite conflict with humans and their threatened status, few Pteropus are being monitored. Often, this is because of difficulties associated with their high mobility, large and easily disturbed aggregations, and their use of unknown or remote habitat. Here we describe 10 years of results from the National Flying-fox Monitoring Program (NFFMP) for the grey-headed flying-fox, (Pteropus poliocephalus) in Australia. Range-wide quarterly surveys were conducted over a three-day period since November 2012 using standardized methods appropriate to conditions encountered at each roost. For our analysis of the population and its trend, we used a state-space model to account for the ecology of the grey-headed flying-fox and the errors associated with the surveying process. Despite the general perception that the species is in decline, our raw data and the modelled population trend suggest the grey-headed flying-fox population has remained stable during the NFFMP period, with the range also stable. These results indicate that the species' extreme mobility and broad diet bestow it with a high level of resilience to various disturbance events. Long-term, range-wide studies such as this one, are crucial for understanding relatively long-lived and highly nomadic species such as the grey-headed flying-fox. The outcomes of this study highlight the need for such systematic population monitoring of all threatened Pteropus species.


Assuntos
Quirópteros , Animais , Humanos , Austrália/epidemiologia , Ecologia , Ecossistema
2.
Animals (Basel) ; 13(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003136

RESUMO

Australia's 2019-2020 bushfires had a devastating impact on animals, humans, and ecosystems. They also demonstrated the lack of evidence or guidance for wildlife provisioning in response to severe fire events when volunteers and wildlife organisations rose to respond. In addition, the unprecedented scale and intensity of the fires and an absence of institutional support for wildlife provisioning meant that well-intentioned interventions were largely uncoordinated and lacked clear short-term, mid-term, and long-term objectives. Fundamentally, a lack of consensus was revealed on whether any such interventions are advisable. Given the strong evidence indicating that future bushfire seasons will become longer and more intense in Australia and elsewhere, the welfare and survival of millions of wild animals are at risk every year. Understanding the impacts of supplementary resource interventions and contributing to the development of best practice information is crucial to inform the response to the next major fire event. Here, we contextualize the arguments for and against provisioning within a 'One Welfare' framework that recognizes that animal welfare, biodiversity, and the environment are intertwined with human welfare and community resilience. We propose that the One Welfare approach can facilitate appropriate consideration of the extant scientific and lay literature; local legislation; views of stakeholders; emerging data; and modelling from historic fire events. As a further step, we see merit in engaging with wildlife provisioners and the broader conservation community to build an evidence base for future wildlife provisioning activities. From an informed position, we can encourage beneficial interventions and reduce the risk of negative outcomes. Finally, we propose controlled experiments (e.g., using hazard reduction burns), ongoing data collection using emergent technology, and longitudinal analysis to address shifting research priorities as the climate changes. We conclude that the ordered collection of the necessary evidence relevant to each of the three stakeholder groups in the One Welfare framework has the greatest potential to support an informed policy platform on wildlife provisioning across Australia that is feasible, legal, and sustainable.

3.
Sci Rep ; 13(1): 12512, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532795

RESUMO

Reliable information on population size is fundamental to the management of threatened species. For wild species, mark-recapture methods are a cornerstone of abundance estimation. Here, we show the first application of the close-kin mark-recapture (CKMR) method to a terrestrial species of high conservation value; the Christmas Island flying-fox (CIFF). The CIFF is the island's last remaining native terrestrial mammal and was recently listed as critically endangered. CKMR is a powerful tool for estimating the demographic parameters central to CIFF management and circumvents the complications arising from the species' cryptic nature, mobility, and difficult-to-survey habitat. To this end, we used genetic data from 450 CIFFs captured between 2015 and 2019 to detect kin pairs. We implemented a novel CKMR model that estimates sex-specific abundance, trend, and mortality and accommodates observations from the kin-pair distribution of male reproductive skew and mate persistence. CKMR estimated CIFF total adult female abundance to be approximately 2050 individuals (95% CI (950, 4300)). We showed that on average only 23% of the adult male population contributed to annual reproduction and strong evidence for between-year mate fidelity, an observation not previously quantified for a Pteropus species in the wild. Critically, our population estimates provide the most robust understanding of the status of this critically endangered population, informing immediate and future conservation initiatives.


Assuntos
Quirópteros , Conservação dos Recursos Naturais , Humanos , Animais , Masculino , Feminino , Espécies em Perigo de Extinção , Densidade Demográfica , Ecossistema , Mamíferos
4.
J Anim Ecol ; 92(1): 171-182, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349451

RESUMO

A preference to associate with kin facilitates inclusive fitness benefits, and increased tolerance or cooperation between kin may be an added benefit of group living. Many species exhibit preferred associations with kin; however, it is often hard to disentangle active preferences from passive overlap, for example caused by limited dispersal or inheritance of social position. Many parrots exhibit social systems consisting of pair-bonded individuals foraging in variably sized fission-fusion flocks within larger communal roosts of hundreds of individuals. Previous work has shown that, despite these fission-fusion dynamics, individuals can exhibit long-term preferred foraging associations outside their pair bonds. Yet the underlying drivers of these social preferences remain largely unknown. In this study, we use a network approach to examine the influence of kinship on social associations and interactions in wild, communally roosting sulphur-crested cockatoos, Cacatua galerita. We recorded roost co-membership, social associations and interactions in 561 individually marked birds across three neighbouring roosts. We then collected genetic samples from 205 cockatoos, and conducted a relationship analysis to construct a kinship network. Finally, we tested correlations between kinship and four social networks: association, affiliative, low-intensity aggression and high-intensity aggression. Our result showed that while roosting groups were clearly defined, they showed little genetic differentiation or kin structuring. Between roost movement was high, with juveniles, especially females, repeatedly moving between roosts. Both within roosting communities, and when visiting different roosts, individuals preferentially associated with kin. Supporting this, individuals were also more likely to allopreen kin. However, contrary to expectation, individuals preferred to direct aggression towards kin, with this effect only observed when individuals shared roost membership. By measuring social networks within and between large roosting groups, we could remove potential effects of passive spatial overlap on kin structuring. Our study reveals that sulphur-crested cockatoos actively prefer to associate with kin, both within and between roosting groups. By examining this across different interaction types, we further demonstrate that sulphur-crested cockatoos exhibit behavioural and context-dependent interaction rules towards kin. Our results help reveal the drivers of social association in this species, while adding to the evidence for social complexity in parrots.


Assuntos
Cacatuas , Papagaios , Feminino , Animais , Análise de Rede Social , Agressão , Enxofre
5.
Curr Biol ; 32(17): R910-R911, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099892

RESUMO

Foraging innovations can give wild animals access to human-derived food sources1. If these innovations spread, they can enable adaptive flexibility2 but also lead to human-wildlife conflicts3. Examples include crop-raiding elephants4 and long-tailed macaques that steal items from people to trade them back for food5. Behavioural responses by humans might act as a further driver on animal innovation2,6, even potentially leading to an inter-species 'innovation arms-race'7, yet this is almost entirely unexplored. Here, we report a potential case in wild, urban-living, sulphur-crested cockatoos (Cacatua galerita; henceforth cockatoos), where the socially-learnt behaviour of opening and raiding of household bins by cockatoos8 is met with increasingly effective and socially-learnt bin-protection measures by human residents.


Assuntos
Cacatuas , Elefantes , Papagaios , Animais , Animais Selvagens , Humanos , Pesquisa
6.
Plant Genome ; 15(4): e20250, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35971881

RESUMO

The phenomenon of preharvest sprouting (PHS), caused by rain after physiological maturity and prior to harvest, negatively affects wheat (Triticum aestivum L.) production and end use. Investigating the genetics that control PHS resistance may result in increased control of seed dormancy. Multiple genes involved in the development of seed dormancy are associated with PHS. In this study, the TaMFT (3A, 3B1, 3B2, 3D), TaMKK3-4A, and TaVP1-3B genes were assessed for association with PHS in a double-haploid line (DHL) hard red winter wheat population derived from a BC1 cross between the cultivars Loma and Warhorse, where Loma was the recurrent and PHS susceptible parent. The 162 BC1 DHL lines were grown over two field seasons and PHS susceptibility was assessed by measuring PHS resistance in physiologically mature heads. The PHS variation was associated with the TaMFT-A and the B2 homeolog with Loma carrying mutant forms of each gene. No sequence variation between Loma and Warhorse was detected in the exons of the TaMFT-B1 and D homeologs. No association between PHS resistance and TaMKK3-4A or TaVp1-3B variation was observed, though Loma and Warhorse vary for TaMKK3-4A and TaVp1-3B mutations reported to be PHS associated. Previous research has shown TaMFT-3A as having a large impact on PHS resistance. In the current study, the TaMFT-3A and TaMFT-3B2 alleles each explained 14% of observed PHS variation. Markers for both TaMFT-3A and TaMFT-3B2 should be used in selecting for increased wheat dormancy and PHS resistance.


Assuntos
Germinação , Triticum , Triticum/genética , Germinação/genética , Alelos , Mutação
7.
Plants (Basel) ; 11(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35807724

RESUMO

The primary goal of common wheat (T. aestivum) breeding is increasing yield without negatively impacting the agronomic traits or product quality. Genetic approaches to improve the yield increasingly target genes that impact the grain weight and number. An energetic trade-off exists between the grain weight and grain number, the result of which is that most genes that increase the grain weight also decrease the grain number. QTL associated with grain weight and number have been identified throughout the hexaploid wheat genome, leading to the discovery of numerous genes that impact these traits. Genes that have been shown to impact these traits will be discussed in this review, including TaGNI, TaGW2, TaCKX6, TaGS5, TaDA1, WAPO1, and TaRht1. As more genes impacting the grain weight and number are characterized, the opportunity is increasingly available to improve common wheat agronomic yield by stacking the beneficial alleles. This review provides a synopsis of the genes that impact grain weight and number, and the most beneficial alleles of those genes with respect to increasing the yield in dryland and irrigated conditions. It also provides insight into some of the genetic mechanisms underpinning the trade-off between grain weight and number and their relationship to the source-to-sink pathway. These mechanisms include the plant size, the water soluble carbohydrate levels in plant tissue, the size and number of pericarp cells, the cytokinin and expansin levels in developing reproductive tissue, floral architecture and floral fertility.

8.
Mov Ecol ; 10(1): 19, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410304

RESUMO

BACKGROUND: Animals are important vectors for the dispersal of a wide variety of plant species, and thus play a key role in maintaining the health and biodiversity of natural ecosystems. On oceanic islands, flying-foxes are often the only seed dispersers or pollinators. However, many flying-fox populations are currently in decline, particularly those of insular species, and this has consequences for the ecological services they provide. Knowledge of the drivers and the scale of flying-fox movements is important in determining the ecological roles that flying-foxes play on islands. This information is also useful for understanding the potential long-term consequences for forest dynamics resulting from population declines or extinction, and so can aid in the development of evidence-based ecological management strategies. To these ends, we examined the foraging movements, floral resource use, and social interactions of the Critically Endangered Christmas Island flying-fox (Pteropus natalis). METHODS: Utilization distributions, using movement-based kernel estimates (MBKE) were generated to determine nightly foraging movements of GPS-tracked P. natalis (n = 24). Generalized linear models (GLMs), linear mixed-effect models (LMMs), and Generalized linear mixed-effects model (GLMMs) were constructed to explain how intrinsic factors (body mass, skeletal size, and sex) affected the extent of foraging movements. In addition, we identified pollen collected from facial and body swabs of P. natalis (n = 216) to determine foraging resource use. Direct observations (n = 272) of foraging P. natalis enabled us to assess the various behaviors used to defend foraging resources. RESULTS: Larger P. natalis individuals spent more time foraging and less time traveling between foraging patches, traveled shorter nightly distances, and had smaller overall foraging ranges than smaller conspecifics. Additionally, larger individuals visited a lower diversity of floral resources. CONCLUSIONS: Our findings suggest that smaller P. natalis individuals are the primary vectors of long-distance dispersal of pollen and digested seeds in this species, providing a vital mechanism for maintaining the flow of plant genetic diversity across Christmas Island. Overall, our study highlights the need for more holistic research approaches that incorporate population demographics when assessing a species' ecological services.

9.
PLoS One ; 16(11): e0259395, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34723974

RESUMO

Urban expansion is a major threat to natural ecosystems but also creates novel opportunities that adaptable species can exploit. The grey-headed flying-fox (Pteropus poliocephalus) is a threatened, highly mobile species of bat that is increasingly found in human-dominated landscapes, leading to many management and conservation challenges. Flying-fox urbanisation is thought to be a result of diminishing natural foraging habitat or increasing urban food resources, or both. However, little is known about landscape utilisation of flying-foxes in human-modified areas, and how this may differ in natural areas. Here we examine positional data from 98 satellite-tracked P. poliocephalus for up to 5 years in urban and non-urban environments, in relation to vegetation data and published indices of foraging habitat quality. Our findings indicate that human-modified foraging landscapes sustain a large proportion of the P. poliocephalus population year-round. When individuals roosted in non-urban and minor-urban areas, they relied primarily on wet and dry sclerophyll forest, forested wetlands, and rainforest for foraging, and preferentially visited foraging habitat designated as high-quality. However, our results highlight the importance of human-modified foraging habitats throughout the species' range, and particularly for individuals that roosted in major-urban environments. The exact plant species that exist in human-modified habitats are largely undocumented; however, where this information was available, foraging by P. poliocephalus was associated with different dominant plant species depending on whether individuals roosted in 'urban' or 'non-urban' areas. Overall, our results demonstrate clear differences in urban- and non-urban landscape utilisation by foraging P. poliocephalus. However, further research is needed to understand the exact foraging resources used, particularly in human-modified habitats, and hence what attracts flying-foxes to urban areas. Such information could be used to modify the urban foraging landscape, to assist long-term habitat management programs aimed at minimising human-wildlife conflict and maximising resource availability within and outside of urban environments.


Assuntos
Quirópteros , Animais , Ecossistema
10.
Science ; 373(6553): 456-460, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34437121

RESUMO

The emergence, spread, and establishment of innovations within cultures can promote adaptive responses to anthropogenic change. We describe a putative case of the development of a cultural adaptation to urban environments: opening of household waste bins by wild sulphur-crested cockatoos. A spatial network analysis of community science reports revealed the geographic spread of bin opening from three suburbs to 44 in Sydney, Australia, by means of social learning. Analysis of 160 direct observations revealed individual styles and site-specific differences. We describe a full pathway from the spread of innovation to emergence of geographic variation, evidencing foraging cultures in parrots and indicating the existence of cultural complexity in parrots. Bin opening is directly linked to human-provided opportunities, highlighting the potential for culture to facilitate behavioral responses to anthropogenic change.


Assuntos
Comportamento Animal , Cacatuas , Criatividade , Comportamento Alimentar , Aprendizado Social , Animais , Cidades , Feminino , Masculino , New South Wales , Análise Espaço-Temporal
11.
PLoS One ; 16(7): e0255421, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324598

RESUMO

Global conservation is increasingly reliant on young people forming meaningful connections with urban nature. However, interactions with nearby nature do not inspire all children and adolescents living in cities to act pro-environmentally. Our survey of over 1,000 school students from Sydney, Australia, revealed that 28% of respondents maintained strong nature connections. Younger students (aged 8-11) were more strongly connected with nature than their older peers (aged 12-14), and environmental behaviors were negatively associated with increasing age. Differences between boys and girls were less consistent, resulting in part from differential functioning of questionnaire items. Regardless, girls were more willing than boys to volunteer for conservation. Our findings suggest that policies designed to strengthen urban children's nature connections will be most effective if they explicitly address the "adolescent dip" and other emerging demographic patterns, thereby ensuring all young people reap the health, wellbeing, and conservation benefits of connecting with nature.


Assuntos
Comportamento do Adolescente , População Urbana , Adolescente , Criança , Feminino , Humanos , Masculino , Assunção de Riscos , Inquéritos e Questionários
12.
Theor Appl Genet ; 134(2): 603-620, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33146737

RESUMO

KEY MESSAGE: Investigation of resource availability on allele effects for four yield component quantitative trait loci provides guidance for the improvement of grain yield in high and low yielding environments. A greater understanding of grain yield (GY) and yield component traits in spring wheat may increase selection efficiency for improved GY in high and low yielding environments. The objective of this study was to determine allelic response of four yield component quantitative trait loci (QTL) to variable resource levels which were manipulated by varying intraspecific plant competition and seeding density. The four QTL investigated in this study had been previously identified as impacting specific yield components. They included QTn.mst-6B for productive tiller number (PTN), WAPO-A1 for spikelet number per spike (SNS), and QGw.mst-3B and TaGW2-A1 for kernel weight (KWT). Near-isogenic lines for each of the four QTL were grown in multiple locations with three competition (border, no-border and space-planted) and two seeding densities (normal 216 seeds m-2 and low 76 seeds m-2). Allele response at QTn.mst-6B was driven by changes in resource availability, whereas allele response at WAPO-A1 and TaGW2-A1 was relatively unaffected by resource availability. The QTn.mst-6B.1 allele at QTn.mst-6B conferred PTN plasticity resulting in significant GY increases in high resource environments. The gw2-A1 allele at TaGW2-A1 significantly increased KWT, SNS and GPC offering a source of GY improvement without negatively impacting end-use quality. QGw.mst-3B allelic variation did not significantly impact KWT but did significantly impact SPS. Treatment effects in both experiments often resulted in significant positive impacts on GY and yield component traits when resource availability was increased. Results provide guidance for leveraging yield component QTL to improve GY performance in high- and low-yield environments.


Assuntos
Cromossomos de Plantas/genética , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas , Sementes/crescimento & desenvolvimento , Sementes/genética , Triticum/crescimento & desenvolvimento , Triticum/genética , Alelos , Mapeamento Cromossômico , Regulação da Expressão Gênica de Plantas , Fenótipo , Melhoramento Vegetal , Proteínas de Plantas/genética , Estações do Ano , Sementes/metabolismo , Triticum/metabolismo
13.
J Anim Ecol ; 90(1): 222-232, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32629533

RESUMO

Parrots are often referenced in discussions of social and cognitive complexity, yet relatively little is known of their social organization in the wild. In particular, the presence of long-lasting social ties has been highlighted as a hallmark of social complexity; however, the presence of such ties can be masked in fission-fusion systems like that exhibited by most parrot species. Social network analysis has the potential to elucidate such multi-level dynamics. While most parrot species are tropical canopy dwellers, a subset has successfully colonized urban habitats, where they are often the focus of much public interest. Our study takes advantage of this to use citizen science to collect observations of wing-tagged sulphur-crested cockatoos in central Sydney and record their social associations over multiple years. Using a specifically designed mobile phone application 'Wingtags', we collected over >27,000 citizen science reports of wing-tagged cockatoos, and built social networks from spatial-temporal co-occurrences in observations for 130 tagged birds. To validate this novel methodology, we GPS-tagged a subset of wing-tagged birds and compared networks built from both data collection methods. We then examined correlates of social network structure before exploring the temporal dynamics of network structure and social associations. Social networks constructed from GPS data and citizen science data were highly correlated, suggesting that this novel methodology is robust. Network structure exhibited little seasonal variability and was largely driven by roost site choice; however, individuals also showed a surprising degree of mixing between roosts in their foraging associations. Finally, within this larger fission-fusion system, individuals tended to maintain specific social ties for long periods of time. There was an effect of age on these temporal dynamics, with aging individuals increasing both social stability and longevity of associations. Our findings highlight the utility of citizen science to measure social networks in urban species, and add to the evidence that long-lasting social associations can persist in fission-fusion social systems such as those observed in wild sulphur-crested cockatoos.


Assuntos
Ciência do Cidadão , Cacatuas , Papagaios , Animais , Rede Social
14.
BMC Biol ; 18(1): 101, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32819385

RESUMO

BACKGROUND: Effective conservation management of highly mobile species depends upon detailed knowledge of movements of individuals across their range; yet, data are rarely available at appropriate spatiotemporal scales. Flying-foxes (Pteropus spp.) are large bats that forage by night on floral resources and rest by day in arboreal roosts that may contain colonies of many thousands of individuals. They are the largest mammals capable of powered flight, and are highly mobile, which makes them key seed and pollen dispersers in forest ecosystems. However, their mobility also facilitates transmission of zoonotic diseases and brings them in conflict with humans, and so they require a precarious balancing of conservation and management concerns throughout their Old World range. Here, we analyze the Australia-wide movements of 201 satellite-tracked individuals, providing unprecedented detail on the inter-roost movements of three flying-fox species: Pteropus alecto, P. poliocephalus, and P. scapulatus across jurisdictions over up to 5 years. RESULTS: Individuals were estimated to travel long distances annually among a network of 755 roosts (P. alecto, 1427-1887 km; P. poliocephalus, 2268-2564 km; and P. scapulatus, 3782-6073 km), but with little uniformity among their directions of travel. This indicates that flying-fox populations are composed of extremely mobile individuals that move nomadically and at species-specific rates. Individuals of all three species exhibited very low fidelity to roosts locally, resulting in very high estimated daily colony turnover rates (P. alecto, 11.9 ± 1.3%; P. poliocephalus, 17.5 ± 1.3%; and P. scapulatus, 36.4 ± 6.5%). This indicates that flying-fox roosts form nodes in a vast continental network of highly dynamic "staging posts" through which extremely mobile individuals travel far and wide across their species ranges. CONCLUSIONS: The extreme inter-roost mobility reported here demonstrates the extent of the ecological linkages that nomadic flying-foxes provide across Australia's contemporary fragmented landscape, with profound implications for the ecosystem services and zoonotic dynamics of flying-fox populations. In addition, the extreme mobility means that impacts from local management actions can readily reverberate across jurisdictions throughout the species ranges; therefore, local management actions need to be assessed with reference to actions elsewhere and hence require national coordination. These findings underscore the need for sound understanding of animal movement dynamics to support evidence-based, transboundary conservation and management policy, tailored to the unique movement ecologies of species.


Assuntos
Tamanho Corporal , Quirópteros/fisiologia , Conservação dos Recursos Naturais , Voo Animal , Animais , Austrália , Movimento , Tecnologia de Sensoriamento Remoto/veterinária
15.
G3 (Bethesda) ; 9(6): 1999-2006, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31015195

RESUMO

The wheat stem sawfly (WSS) (Cephus cinctus Norton) is a major yield-reducing pest of wheat (Triticum aestivum L.). Varieties with pith-filled, or solid, stems provide a measure of resistance by inhibiting larval survival inside the stem. Durum wheat (Triticum turgidum L.) has resistance to the wheat stem sawfly even in the absence of known genes for stem solidness. To determine the genetic basis of resistance in durum wheat, a susceptible durum wheat, PI 41353, was identified from among 1,211 landrace accessions from around the world screened in WSS-infested sites. A recombinant inbred line (RIL) population of 105 individuals was developed from a cross of PI 41353 with a typically resistant variety, Pierce. The RIL were screened in a total of three WSS-infested locations in Montana over a two year period. A genetic map was constructed with 2,867 SNP-based markers. A quantitative trait locus (QTL) analysis identified six QTL associated with resistance. An allele from resistant cultivar Pierce at a QTL on chromosome 3A, Qss.msub-3AL, caused a 25% reduction in stem cutting. Assessment of near-isogenic lines that varied for alleles at Qss.msub-3AL showed that the Pierce allele was also associated with higher stem solidness as measured early in stem development, which is a critical stage for WSS oviposition and larval development. Stem solidness of Pierce and other resistant durum wheat lines largely disappeared later in plant development. Results suggest a genetic mechanism for WSS resistance observed in durum wheat, and provide an additional source of WSS resistance for hexaploid bread wheat.


Assuntos
Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Locos de Características Quantitativas , Característica Quantitativa Herdável , Triticum/genética , Triticum/parasitologia , Alelos , Mapeamento Cromossômico , Resistência à Doença/genética , Ligação Genética , Genótipo , Interações Hospedeiro-Parasita , Polimorfismo de Nucleotídeo Único
16.
Plant Sci ; 281: 180-185, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30824050

RESUMO

Pre-harvest sprouting (PHS) of wheat (Triticum aestivum L.) is an important phenomenon that results in weather dependent reductions in grain yield and quality across the globe. Due to the large annual losses, breeding PHS resistant varieties is of great importance. Many quantitative trait loci have been associated with PHS and a number of specific genes have been proven to impact PHS. TaPHS1, TaMKK3, Tamyb10, and TaVp1 have been shown to have a large impact on PHS susceptibility while many other genes such as TaSdr, TaQSd, and TaDOG1 have been shown to account for smaller, but significant, proportions of variation. These advances in understanding the genetics behind PHS are making molecular selection and loci stacking viable methods for affecting this quantitative trait. The current review article serves to provide a brief synthesis of recent advances regarding PHS, as well as provide unique insight into the genetic mechanisms governing PHS in bread wheat.


Assuntos
Triticum/genética , Genótipo , Germinação/genética , Germinação/fisiologia , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
17.
Front Plant Sci ; 10: 51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30778362

RESUMO

The Reduced Height (Rht) genes formed the basis for the green revolution in wheat by decreasing plant height and increasing productive tillers. There are two current widely used Rht mutant alleles, Rht-B1b and Rht-D1b. Both reduce plant height by 20% and increase seed yield by 5-10%. They are also associated with decreased seed size and protein content. Here, we tested the degree to which Rht-B1b impacts flag leaf photosynthetic rates and carbon and nitrogen partitioning to the flag leaf and grain during grain fill under field conditions using near isogenic lines (NILs) that were either standard height (Rht-B1a) or semi-dwarf (Rht-B1b). The results demonstrate that at anthesis, Rht-B1b reduces flag leaf photosynthetic rate per unit area by 18% and chlorophyll A content by 23%. Rht-B1b significantly reduced grain protein beginning at 14 days post anthesis (DPA) with the greatest difference seen at 21 DPA (12%). Rht-B1b also significantly decreased individual seed weight beginning at 21 DPA and by 15.2% at 28 DPA. Global expression analysis using RNA extracted from developing leaves and stems demonstrated that genes associated with carbon and nitrogen metabolism are not substantially altered by Rht-B1b. From this study, we conclude that Rht-B1b reduces flag leaf photosynthetic rate at flowering while changes in grain composition begin shortly after anthesis.

18.
J Mammal ; 99(6): 1510-1521, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30538341

RESUMO

Flying foxes (family Pteropodidae) have distinct life histories given their size, characterized by longevity, low reproductive output, and long gestation. However, they tend to decouple the age at which sexual maturity is reached from the age at which they reach adult dimensions. We examined growth, maturation, and reproduction in the Critically Endangered Christmas Island flying fox (Pteropus natalis) to determine the timing of sex-specific life cycle events and patterns of growth. We estimated that juvenile growth in forearm length and body mass increased at a mean rate of 0.029 ± 0.005 mm/day and 0.33 ± 0.07 g/day for both males and females alike. Using these growth rates, we determined that the birth of pups occurs between December and March, with young becoming volant between June and August. The age at maturation for P. natalis is one of the oldest among all bat species. Juvenile males began to mature 15 months after birth and reached maturity 27 months after birth. Females reached maturity 24 months after birth at a significantly smaller body mass (3.6%) and forearm length (1.4%) than males. Significant sexual dimorphism and bimaturation was observed, with juvenile males being 1.5% and adult males being 1.9% larger on average than females for skeletal dimensions only. Growth and maturation are even slower in P. natalis than in the few other Pteropus species studied to date. The slow growth and delayed maturation of P. natalis imply slower potential population growth rates, further complicating the recovery of this Critically Endangered single-island endemic.

19.
PLoS One ; 13(8): e0201962, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30133503

RESUMO

Dental mesowear analysis can classify the diets of extant herbivores into general categories such as grazers, mixed-feeders, and browsers by using the gross wear patterns found on individual teeth. This wear presumably results from both abrasion (food-on-tooth wear) and attrition (tooth-on-tooth wear) of individual teeth. Mesowear analyses on extinct ungulates have helped generate hypotheses regarding the dietary ecology of mammals across space and time, and recent developments have expanded the use of dental mesowear analysis to herbivorous marsupial taxa including kangaroos, wombats, possums, koalas, and relatives. However, the diet of some of the most ubiquitous kangaroos (e.g., Macropus giganteus) along with numerous other species cannot be successfully classified by dental mesowear analysis. Further, it is not well understood whether climate variables (including precipitation, relative humidity, and temperature) are correlated with dental mesowear variables including various measures of shape and relief. Here, we examine the relationship between dental mesowear variables (including traditional methods scoring the sharpest cusp and a new potential assessment of multiple cusps) and climate variables in the grazers/mixed feeders Macropus giganteus and Macropus fuliginosus, and the obligate browser Phascolarctos cinereus. We find that dental mesowear of mandibular teeth is capable of differentiating the dietary habits of koalas and the kangaroo species. Furthermore, both Macropus giganteus and Phascolarctos cinereus exhibit mesowear correlated with mean minimum temperature, while Macropus fuliginosus dental mesowear is unaffected by temperature, despite significant differences in mean minimum and mean maximum temperature across their distribution (and in the specimens examined here). Contrary to expectations that individuals from drier regions would have blunter and lower relief teeth, dental mesowear is unrelated to proxies of relative aridity-including mean annual precipitation and relative humidity. Collectively, dental mesowear in these marsupials is related to feeding behavior with increased wear in cooler regions (in Macropus giganteus and Phascolarctos cinereus) potentially related to more or different food resources consumed.


Assuntos
Clima , Herbivoria , Macropodidae , Phascolarctidae , Desgaste dos Dentes , Animais , Geografia , Macropodidae/fisiologia , Phascolarctidae/fisiologia , Dinâmica Populacional
20.
Hum Gene Ther Methods ; 28(3): 124-138, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28504553

RESUMO

Adeno-associated virus (AAV) producer cell lines are created via transfection of HeLaS3 cells with a single plasmid containing three components (the vector sequence, the AAV rep and cap genes, and a selectable marker gene). As this plasmid contains both the cis (Rep binding sites) and trans (Rep protein encoded by the rep gene) elements required for site-specific integration, it was predicted that plasmid integration might occur within the AAVS1 locus on human chromosome 19 (chr19). The objective of this study was to investigate whether integration in AAVS1 might be correlated with vector yield. Plasmid integration sites within several independent cell lines were assessed via Southern, fluorescence in situ hybridization (FISH) and PCR analyses. In the Southern analyses, the presence of fragments detected by both rep- and AAVS1-specific probes suggested that for several mid- and high-producing lines, plasmid DNA had integrated into the AAVS1 locus. Analysis with puroR and AAVS1-specific probes suggested that integration in AAVS1 was a more widespread phenomenon. High-producing AAV2-secreted alkaline phosphatase (SEAP) lines (masterwell 82 [MW82] and MW278) were evaluated via FISH using probes specific for the plasmid, AAVS1, and a chr19 marker. FISH analysis detected two plasmid integration sites in MW278 (neither in AAVS1), while a total of three sites were identified in MW82 (two in AAVS1). An inverse PCR assay confirmed integration within AAVS1 for several mid- and high-producing lines. In summary, the FISH, Southern, and PCR data provide evidence of site-specific integration of the plasmid within AAVS1 in several AAV producer cell lines. The data also suggest that integration in AAVS1 is a general phenomenon that is not necessarily restricted to high producers. The results also suggest that plasmid integration within the AAVS1 locus is not an absolute requirement for a high vector yield.


Assuntos
Dependovirus/genética , Marcação de Genes/métodos , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Células HeLa , Humanos , Recombinação Genética
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