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1.
J Med Entomol ; 61(5): 1140-1148, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38920309

RESUMO

In Diptera, reproductive strategies vary according to the stage of development of the newly deposited offspring and their abundance. The aim of our study is to establish connections between the reproductive strategies of flies (larviparous or oviparous) and the prevailing local conditions (sun or shade) as well as landscape attributes (low or high urbanization) in an urban setting. We collected flies using 2 baited traps (in the sun or shade) at each of the 13 study sites with varying levels of urbanization. We used generalized linear mixed models to examine the impact of landscape and local characteristics on the diversity (abundance and richness of larviparous and oviparous Diptera) of sarcosaprophagous flies. Our findings indicate that while the abundance and diversity of both larviparous and oviparous flies are affected by urbanization, larviparous flies would be less sensitive to more urbanized environments. Larviparous also exhibit a preference for resources under sun exposure, while the responses of oviparous seem more species-dependent. The observed patterns can be explained by the known biology of the studied groups.


Assuntos
Dípteros , Urbanização , Animais , Dípteros/fisiologia , Oviparidade , Larva/fisiologia , Larva/crescimento & desenvolvimento , Cidades , Feminino , Viviparidade não Mamífera , Reprodução , Biodiversidade
2.
Evol Psychol ; 20(3): 14747049221096758, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35791511

RESUMO

Previous research has yielded mixed findings on the relationship between facial width-to-height ratio (fWHR), an androgen-dependent feature, and risk-taking propensity. We argue that mixed findings might result from overlooked variables. Given that risk-taking propensity might be ultimately linked to a search for mating opportunities, we analyze if reproductive strategies moderate the relationship between fWHR and risk-taking propensity. Our results, obtained from a sample of 434 male participants, show a positive association between fWHR and recreational and social risk-taking only for men who are more motivated to focus on mating effort over offspring survival. This finding aligns with research arguing that risk-taking may be a mating strategy since being social and recreational risk-prone might illustrate physical and psychological qualities and improve one's ability to attract mates. Our results support the notion that risk-taking might be a domain-specific construct. Overall, our research is in line with recent findings suggesting that the impact of testosterone exposure on risk-taking propensity is best understood when considering the role of contextual variables. Consequently, we add to previous research that studies related to risk-taking propensity should account for reproductive strategies.


Assuntos
Face , Testosterona , Humanos , Masculino , Assunção de Riscos
3.
Am J Primatol ; 82(12): e23190, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32944998

RESUMO

Among non-human primates, alloparental infant care is most extensive in callitrichines, and is thought to be particularly costly for tamarins whose helpers may suffer increased energy expenditure, weight loss, and reduced feeding time and mobility. The costs and benefits of infant care likely vary among group members yet very few wild studies have investigated variable infant care contributions. We studied infant care over an 8-month period in four wild groups of saddleback tamarins in Bolivia to evaluate: (a) what forms of infant care are provided, by whom, and when, (b) how individuals adjust their behavior (activity, vigilance, height) while caring for infants, and (c) whether individuals differ in their infant care contributions. We found that infant carrying, food sharing, and grooming varied among groups, and immigrant males-those who joined the group after infants were conceived-participated less in infant care compared to resident males. Adult tamarins fed less, rested more, and increased vigilance while carrying infants. Although we did not detect changes in overall activity budgets between prepartum and postpartum periods, tamarins spent more time scanning their environments postpartum, potentially reflecting increased predation risk to both carriers and infants during this period. Our study provides the first quantitative data on the timing and amount of infant carrying, grooming, and food transfer contributed by all individuals within and among multiple wild groups, filling a critical knowledge gap about the factors affecting infant care, and highlighting evolutionary hypotheses for cooperative breeding in tamarins.


Assuntos
Comportamento Materno , Comportamento Paterno , Saguinus/psicologia , Animais , Bolívia , Feminino , Masculino , Comportamento Social
5.
Artigo em Inglês | MEDLINE | ID: mdl-30158956

RESUMO

This work aims to contribute to the general information on scorpion reproductive patterns in general including species that can be noxious to humans. Scorpions are unusual among terrestrial arthropods in several of their life-history traits since in many aspects their reproductive strategies are more similar to those of superior vertebrates than to those of arthropods in general. This communication focuses mainly on the aspects concerning embryonic and post-embryonic developments since these are quite peculiar in scorpions and can be directly connected to the scorpionism problem. As in previous similar contributions, the content of this communication is addressed mainly to non-specialists whose research embraces scorpions in several fields such as venom toxins and public health. A precise knowledge of reproductive strategies presented by several scorpion groups and, in particular, those of dangerous species may prove to be a useful tool in the interpretation of results dealing with scorpionism, and also lead to a better treatment of the problems caused by infamous scorpions.

6.
Plant Biol (Stuttg) ; 20(4): 797-801, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29573080

RESUMO

Monomorphic enantiostylous species produce flowers with a displacement of the style to the left (L) or right (R) on the same individual, and may exhibit different dynamics for the production of these floral types, which may influence levels of selfing. We investigated the production dynamics of L and R floral types in seven species and a variety of monomorphic enantiostylous species of the genera Senna and Chamaecrista. Our hypothesis was that most species present similar proportions of floral morphs each day. Individuals were classified daily over a period of 7 days according to the functional status, i.e. the proportion of floral morphs as functionally L, R or reciprocal (REC, i.e. similar proportions of the two floral morphs), and also according to the number of consecutive days in which they exhibited the same functional status. All species presented low daily flower production. Most species had individuals classified as functionally R, L and REC, and tend to repeat the same functional status over a few days, although they may change functional status during the flowering period. All species exhibited individuals that were classified as functionally reciprocal when both the daily and total number of flowers produced over 7 days was considered. The occurrence of different functional status has not yet been reported in the literature for enantiostylous species. The distinct strategies observed in the dynamics of floral morph production seemed likely to minimise geitonogamy and to favour cross-pollination between individuals (xenogamy).


Assuntos
Fabaceae/fisiologia , Flores/fisiologia , Brasil , Fabaceae/anatomia & histologia , Flores/anatomia & histologia
7.
Artigo em Inglês | VETINDEX | ID: vti-734775

RESUMO

This work aims to contribute to the general information on scorpion reproductive patterns in general including species that can be noxious to humans. Scorpions are unusual among terrestrial arthropods in several of their life-history traits since in many aspects their reproductive strategies are more similar to those of superior vertebrates than to those of arthropods in general. This communication focuses mainly on the aspects concerning embryonic and post-embryonic developments since these are quite peculiar in scorpions and can be directly connected to the scorpionism problem. As in previous similar contributions, the content of this communication is addressed mainly to non-specialists whose research embraces scorpions in several fields such as venom toxins and public health. A precise knowledge of reproductive strategies presented by several scorpion groups and, in particular, those of dangerous species may prove to be a useful tool in the interpretation of results dealing with scorpionism, and also lead to a better treatment of the problems caused by infamous scorpions.(AU)


Assuntos
Animais , Escorpiões , Comportamento Reprodutivo , Desenvolvimento Embrionário
8.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;24: 19, 2018. ilus
Artigo em Inglês | LILACS | ID: biblio-954853

RESUMO

This work aims to contribute to the general information on scorpion reproductive patterns in general including species that can be noxious to humans. Scorpions are unusual among terrestrial arthropods in several of their life-history traits since in many aspects their reproductive strategies are more similar to those of superior vertebrates than to those of arthropods in general. This communication focuses mainly on the aspects concerning embryonic and post-embryonic developments since these are quite peculiar in scorpions and can be directly connected to the scorpionism problem. As in previous similar contributions, the content of this communication is addressed mainly to non-specialists whose research embraces scorpions in several fields such as venom toxins and public health. A precise knowledge of reproductive strategies presented by several scorpion groups and, in particular, those of dangerous species may prove to be a useful tool in the interpretation of results dealing with scorpionism, and also lead to a better treatment of the problems caused by infamous scorpions.(AU)


Assuntos
Animais , Masculino , Feminino , Escorpiões/crescimento & desenvolvimento , Escorpiões/embriologia , História Reprodutiva , Picadas de Escorpião
9.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;24: 1-12, 2018. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484760

RESUMO

This work aims to contribute to the general information on scorpion reproductive patterns in general including species that can be noxious to humans. Scorpions are unusual among terrestrial arthropods in several of their life-history traits since in many aspects their reproductive strategies are more similar to those of superior vertebrates than to those of arthropods in general. This communication focuses mainly on the aspects concerning embryonic and post-embryonic developments since these are quite peculiar in scorpions and can be directly connected to the scorpionism problem. As in previous similar contributions, the content of this communication is addressed mainly to non-specialists whose research embraces scorpions in several fields such as venom toxins and public health. A precise knowledge of reproductive strategies presented by several scorpion groups and, in particular, those of dangerous species may prove to be a useful tool in the interpretation of results dealing with scorpionism, and also lead to a better treatment of the problems caused by infamous scorpions.


Assuntos
Animais , Comportamento Reprodutivo , Desenvolvimento Embrionário , Escorpiões
10.
Rev. biol. trop ; Rev. biol. trop;65(3): 1082-1094, Jul.-Sep. 2017. tab, ilus
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-897604

RESUMO

Abstract: The distribution of amphibians is affected by abiotic and biotic factors, availability of resources and the characteristics of reproductive sites. In particular, reproductive activity of aquatic-breeding anurans that inhabit tropical dry areas is affected by rainfall, which determines the availability and quality of reproductive sites. In this study, we analyzed the spatial and temporal distribution of anurans with indirect development in a tropical dry forest in Western Mexico, during two rainy seasons (July 10-October 4, 2013, and June 26-September 26, 2014). We collected data on the occupancy and reproductive activity of 15 species in four temporary streams, and evaluated their relationship with precipitation, humidity and temperature. We determined richness, abundance and diversity of species in each stream; we also identified differences in the reproductive strategies and microhabitats used by the species. The most abundant species were: Tlalocohyla smithii and Exerodonta smaragdina, whereas the least abundant were Leptodactylus melanonotus and Incilius mazatlanensis. Species richness, abundance and reproductive activity peaked alongside the stream with the greatest number of breeding sites (e.g. pools). We found temporal segregation in the occupancy and reproductive activity of species in all streams which were mainly associated with precipitation. However, occupancy and reproductive activity of some species overlapped up to four weeks during part of the breeding season. Most species used specific substrates for particular reproductive activities (e.g. oviposition), but used a range of microhabitats (leaf-litter, water, rocks, branches, leaves, logs, etc.) for others (e.g. calling). We discuss these behavioral differences as factors that facilitate coexistence of species in this environment in the rainy season. Rev. Biol. Trop. 65 (3): 1082-1094. Epub 2017 September 01.


Resumen: La distribución de los anfibios se ve afectada por factores bióticos y abióticos, la disponibilidad de recursos y las características de los sitios de reproducción. En particular, la actividad reproductiva de los anuros que habitan las zonas tropicales secas se ve afectada por las lluvias, que determinan la disponibilidad y calidad de los sitios de reproducción. En este estudio, se analizó la distribución espacial y temporal de los anuros en un bosque tropical seco en el oeste de México durante dos temporadas de lluvias (10 de julio- 4 de octubre 2013 y 26 de junio- 26 de septiembre 2014). Se tomaron datos sobre la presencia de 15 especies de anuros con reproducción acuática en cuatro arroyos temporales y su relación con la precipitación, la humedad y la temperatura. Se determinó la riqueza, abundancia y diversidad de especies en cada arroyo; así como, las diferencias en las estrategias de reproducción y el uso de microhábitats por cada especie. Las especies más abundantes fueron: Tlalocohyla smithii y Exerodonta smaragdina, mientras que las menos abundantes fueron Leptodactylus melanonotus e Incilius mazatlanensis. La mayor riqueza, abundancia y actividad reproductiva se registró en el arroyo con el mayor número de sitios para la reproducción (charcas). Encontramos una segregación temporal en la presencia y actividad reproductiva de las especies que se asoció principalmente con la precipitación. También se observó una superposición de especies en algunas semanas durante la temporada de lluvias. La mayoría de las especies utilizaron sustratos específicos para determinadas actividades (por ejemplo, puesta de huevos), pero utilizaron una variedad de microhábitats para otras actividades (por ejemplo, vocalización). Discutimos estas diferencias de comportamiento como factores que facilitan la coexistencia de estas especies de anuros en este ambiente durante la estación lluviosa.

11.
Mol Phylogenet Evol ; 95: 94-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26642825

RESUMO

Internal fertilization is a widespread mode of reproduction in chondrichthyans and tetrapods, but uncommon in actinopterygian fishes. In killifishes of the suborder Aplocheiloidei, internal fertilization is restricted to two genera, Campellolebias and Cynopoecilus, both containing species adapted to life in seasonal pools of subtropical South America and exhibiting elaborated inseminating structures. Phylogenetic studies involving these genera are scarce and limited to morphological characters and fragments of mitochondrial DNA sequences available for a few taxa, providing incongruent results and thus impeding hypotheses on the evolution of insemination and related morphological traits. We analyzed three nuclear loci (GLYT1, ENC1, Rho) for 13 aplocheiloid taxa obtaining the first well-supported phylogeny for cynopoecilines, thus providing a significant background to interpret evolutionary changes within the group. Like in killifishes of the suborder Cyprinodontoidei, the evolution of internal fertilization in aplocheiloids is associated with deep changes in the structure of male anal fin. The phylogenetic analyses indicate that internal fertilization corresponds to a single evolutionary event during the evolution of aplocheiloid killifishes. The analyses also indicate that male specialized muscle characters, comprising a muscular ejaculatory pump in the urogenital region and hypertrophied inclinatores and depressores anales, arose in the ancestor of the clade comprising Campellolebias and Cynopoecilus. On the other hand, anal fin specialized structures including the male inseminating tube of Campellolebias and the male inseminating fan of Cynopoecilus evolved independently in each genus.


Assuntos
Fertilização/genética , Peixes Listrados/anatomia & histologia , Peixes Listrados/classificação , Peixes Listrados/genética , Reprodução/genética , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/fisiologia , Animais , Evolução Biológica , Cromossomos , DNA Mitocondrial/genética , Inseminação/genética , Masculino , Filogenia , Estações do Ano , Comportamento Sexual Animal , América do Sul , Estados Unidos
12.
Braz. j. biol ; Braz. j. biol;75(3s1): 47-54, Aug. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769592

RESUMO

Abstract The zooplankton community of the lower Xingu River shows strong fluctuations in species richness and number of organisms during periods of water level fluctuation. Pulses of density and species richness are adapted to the pulses in water flows and water level. This is conected with reproductive strategies of some zooplankton groups. The spatial heterogeneity of the lower Xingu River consisting of braided channels, bedrocks, macrophyte stands, is probably a relevant factor for the species richness of the zooplankton communities, and may be a fundamental factor for the overall aquatic biodiversity of the lower Xingu River.


Resumo A comunidade zooplanctônica do Baixo Rio Xingú apresenta grandes flutuações em riqueza de espécies e na densidade (no org./m3) durante os diferentes períodos de flutuação do nível da água. Pulsos de densidade e de riqueza de espécies, são adaptados e ajustados aos pulsos em nível da água e fluxo. Isto está conectado com as estratégias reprodutivas de certos grupos de zooplancton. A heterogeneidade espacial do baixo Rio Xingú consistindo de canais anastomosados, pedrais, macrófitas aquáticas é provavelmente um fator relevante que impulsiona a riqueza de espécies das comunidades zooplanctõnicas e pode ser um fator fundamental para a alta biodiversidade aquática do Rio Xingú.


Assuntos
Animais , Distribuição Animal , Biodiversidade , Rios , Ciclo Hidrológico , Zooplâncton/fisiologia , Brasil
13.
Braz. j. biol ; Braz. j. biol;75(3)Aug. 2015.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468266

RESUMO

Abstract The zooplankton community of the lower Xingu River shows strong fluctuations in species richness and number of organisms during periods of water level fluctuation. Pulses of density and species richness are adapted to the pulses in water flows and water level. This is conected with reproductive strategies of some zooplankton groups. The spatial heterogeneity of the lower Xingu River consisting of braided channels, bedrocks, macrophyte stands, is probably a relevant factor for the species richness of the zooplankton communities, and may be a fundamental factor for the overall aquatic biodiversity of the lower Xingu River.


Resumo A comunidade zooplanctônica do Baixo Rio Xingú apresenta grandes flutuações em riqueza de espécies e na densidade (no org./m3) durante os diferentes períodos de flutuação do nível da água. Pulsos de densidade e de riqueza de espécies, são adaptados e ajustados aos pulsos em nível da água e fluxo. Isto está conectado com as estratégias reprodutivas de certos grupos de zooplancton. A heterogeneidade espacial do baixo Rio Xingú consistindo de canais anastomosados, pedrais, macrófitas aquáticas é provavelmente um fator relevante que impulsiona a riqueza de espécies das comunidades zooplanctõnicas e pode ser um fator fundamental para a alta biodiversidade aquática do Rio Xingú.

14.
Braz. j. biol ; Braz. j. biol;75(3,supl.1): 47-54, Aug. 2015. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468293

RESUMO

The zooplankton community of the lower Xingu River shows strong fluctuations in species richness and number of organisms during periods of water level fluctuation. Pulses of density and species richness are adapted to the pulses in water flows and water level. This is conected with reproductive strategies of some zooplankton groups. The spatial heterogeneity of the lower Xingu River consisting of braided channels, bedrocks, macrophyte stands, is probably a relevant factor for the species richness of the zooplankton communities, and may be a fundamental factor for the overall aquatic biodiversity of the lower Xingu River.


A comunidade zooplanctônica do Baixo Rio Xingú apresenta grandes flutuações em riqueza de espécies e na densidade (no org./m3) durante os diferentes períodos de flutuação do nível da água. Pulsos de densidade e de riqueza de espécies, são adaptados e ajustados aos pulsos em nível da água e fluxo. Isto está conectado com as estratégias reprodutivas de certos grupos de zooplancton. A heterogeneidade espacial do baixo Rio Xingú consistindo de canais anastomosados, pedrais, macrófitas aquáticas é provavelmente um fator relevante que impulsiona a riqueza de espécies das comunidades zooplanctõnicas e pode ser um fator fundamental para a alta biodiversidade aquática do Rio Xingú.


Assuntos
Animais , Biodiversidade , Ciclo Hidrológico , Distribuição Animal , Rios , Zooplâncton/fisiologia , Brasil
15.
Braz. J. Biol. ; 75(3,supl.1): 47-54, Aug. 2015. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-341493

RESUMO

The zooplankton community of the lower Xingu River shows strong fluctuations in species richness and number of organisms during periods of water level fluctuation. Pulses of density and species richness are adapted to the pulses in water flows and water level. This is conected with reproductive strategies of some zooplankton groups. The spatial heterogeneity of the lower Xingu River consisting of braided channels, bedrocks, macrophyte stands, is probably a relevant factor for the species richness of the zooplankton communities, and may be a fundamental factor for the overall aquatic biodiversity of the lower Xingu River.(AU)


A comunidade zooplanctônica do Baixo Rio Xingú apresenta grandes flutuações em riqueza de espécies e na densidade (no org./m3) durante os diferentes períodos de flutuação do nível da água. Pulsos de densidade e de riqueza de espécies, são adaptados e ajustados aos pulsos em nível da água e fluxo. Isto está conectado com as estratégias reprodutivas de certos grupos de zooplancton. A heterogeneidade espacial do baixo Rio Xingú consistindo de canais anastomosados, pedrais, macrófitas aquáticas é provavelmente um fator relevante que impulsiona a riqueza de espécies das comunidades zooplanctõnicas e pode ser um fator fundamental para a alta biodiversidade aquática do Rio Xingú.(AU)


Assuntos
Animais , Distribuição Animal , Biodiversidade , Rios , Ciclo Hidrológico , Zooplâncton/fisiologia , Brasil
16.
Am J Bot ; 102(5): 745-57, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26022488

RESUMO

PREMISE OF THE STUDY: Isometric and allometric scaling of a conserved floral plan could provide a parsimonious mechanism for rapid and reversible transitions between breeding systems. This scaling may occur during transitions between predominant autogamy and xenogamy, contributing to the maintenance of a stable mixed mating system. METHODS: We compared nine disjunct populations of the polytypic, mixed mating species Oenothera flava (Onagraceae) to two parapatric relatives, the obligately xenogamous species O. acutissima and the mixed mating species O. triloba. We compared floral morphology of all taxa using principal component analysis (PCA) and developmental trajectories of floral organs using ANCOVA homogeneity of slopes. KEY RESULTS: The PCA revealed both isometric and allometric scaling of a conserved floral plan. Three principal components (PCs) explained 92.5% of the variation in the three species. PC1 predominantly loaded on measures of floral size and accounts for 36% of the variation. PC2 accounted for 35% of the variation, predominantly in traits that influence pollinator handling. PC3 accounted for 22% of the variation, primarily in anther-stigma distance (herkogamy). During O. flava subsp. taraxacoides development, style elongation was accelerated relative to anthers, resulting in positive herkogamy. During O. flava subsp. flava development, style elongation was decelerated, resulting in zero or negative herkogamy. Of the two populations with intermediate morphology, style elongation was accelerated in one population and decelerated in the other. CONCLUSIONS: Isometric and allometric scaling of floral organs in North American Oenothera section Lavauxia drive variation in breeding system. Multiple developmental paths to intermediate phenotypes support the likelihood of multiple mating system transitions.


Assuntos
Flores/anatomia & histologia , Oenothera/anatomia & histologia , Oenothera/fisiologia , Evolução Biológica , Flores/genética , Flores/fisiologia , Geografia , México , Oenothera/genética , Fenótipo , Reprodução , Estados Unidos
17.
PeerJ ; 3: e899, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25893150

RESUMO

Partible paternity refers to the conception belief that children can have multiple fathers ("co-fathers") and is common to indigenous cultures of lowland South America. The nature of social relationships observed between co-fathers reveals information about the reproductive strategies underlying partible paternity. Here we analyze clan, genealogical, and social relationships between co-fathers for the Suruí, an indigenous horticultural population in Brazil. We show that co-fathers roughly assort into two separate categories. In the affiliative category, co-father relationships are amicable when they are between close kin, namely brothers and father-son. In the competitive category, relationships are more likely of avoidance or open hostility when between more distant kin such as cousins or unrelated men of different clans. Results therefore imply multiple types of relationships, including both cooperative and competitive contexts, under the rubric of partible paternity. These complexities of partible paternity institutions add to our knowledge of the full range of cross-cultural variation in human mating/marriage arrangements and speak to the debate on whether or not humans should be classified as cooperative breeders.

18.
Braz. j. biol ; Braz. j. biol;74(3): 744-749, 8/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-723881

RESUMO

Body size is one of the most important factors regarding herbaceous perennial plants life-histories, and several fitness components of these organisms are related to size. Clonal plants show distinct kinds of reproduction and can develop offspring by sexual or asexual ways. We aimed to understand how body size affects Comanthera nivea (Eriocaulaceae) sexual reproduction and to verify how clonal growth is related to flower head production in this species. We sampled 600 rosettes in rupestrian grasslands and performed linear regression analysis between body size and number of produced flower heads. We also compared the flower head production between isolated rosettes and rosettes within clones. Our results showed that body size was significantly related, but explained only a small part of flower head production. The flower head production was higher in rosettes within clones than in isolated ones. The clones presented a rosette or a small group of rosettes that concentrated the sexual reproduction. Clonality was positively associated with sexual reproduction. Clonality can represent an important way of allowing the persistence of plants by sexual reproduction in markedly seasonal stressful environments. The cases of clonality enhancing the sexual reproduction must be considered and put in focus on reproductive biology research.


O tamanho de corpo é um dos atributos de história de vida mais importantes para plantas herbáceas perenes e muitos componentes da aptidão desses organismos são relacionados ao tamanho. As plantas clonais apresentam diferentes tipos de reprodução e podem gerar prole por vias sexuadas ou assexuadas. Nosso objetivo foi compreender como o tamanho de corpo afeta a reprodução sexual em Comanthera nivea e verificar como o crescimento clonal relaciona-se à produção de capítulos dessa espécie. Nós amostramos 600 rosetas em campos rupestres e utilizamos regressões lineares para verificar a relação entre o tamanho de corpo e o número de capítulos produzidos pela planta. Nós também comparamos a produção de capítulos entre rosetas isoladas e rosetas pertencentes a clones. Nossos resultados mostram que o tamanho de corpo tem influência positiva significativa na produção de capítulos, mas explica apenas parte da variação nos dados. A produção de capítulos é maior em rosetas pertencentes a clones que em rosetas isoladas. Os clones geralmente apresentam uma roseta, ou um grupo de rosetas, que concentra a reprodução sexual. A clonalidade apresentou ligações significativas com a reprodução sexuada. Em ambientes sazonais a clonalidade pode representar uma importante forma de persistência das plantas já que pode permitir um melhor desempenho da reprodução sexuada em vista dos estresses ambientais. Os casos nos quais a clonalidade representa uma via de melhor desempenho para a reprodução sexuada devem ser considerados e colocados em foco na pesquisa em biologia reprodutiva.


Assuntos
Eriocaulaceae/anatomia & histologia , Eriocaulaceae/fisiologia , Brasil , Eriocaulaceae/classificação , Flores/crescimento & desenvolvimento , Reprodução/fisiologia , Estações do Ano
19.
Braz. J. Biol. ; 74(3): 744-749, 8/2014. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-13515

RESUMO

Body size is one of the most important factors regarding herbaceous perennial plants life-histories, and several fitness components of these organisms are related to size. Clonal plants show distinct kinds of reproduction and can develop offspring by sexual or asexual ways. We aimed to understand how body size affects Comanthera nivea (Eriocaulaceae) sexual reproduction and to verify how clonal growth is related to flower head production in this species. We sampled 600 rosettes in rupestrian grasslands and performed linear regression analysis between body size and number of produced flower heads. We also compared the flower head production between isolated rosettes and rosettes within clones. Our results showed that body size was significantly related, but explained only a small part of flower head production. The flower head production was higher in rosettes within clones than in isolated ones. The clones presented a rosette or a small group of rosettes that concentrated the sexual reproduction. Clonality was positively associated with sexual reproduction. Clonality can represent an important way of allowing the persistence of plants by sexual reproduction in markedly seasonal stressful environments. The cases of clonality enhancing the sexual reproduction must be considered and put in focus on reproductive biology research.(AU)


O tamanho de corpo é um dos atributos de história de vida mais importantes para plantas herbáceas perenes e muitos componentes da aptidão desses organismos são relacionados ao tamanho. As plantas clonais apresentam diferentes tipos de reprodução e podem gerar prole por vias sexuadas ou assexuadas. Nosso objetivo foi compreender como o tamanho de corpo afeta a reprodução sexual em Comanthera nivea e verificar como o crescimento clonal relaciona-se à produção de capítulos dessa espécie. Nós amostramos 600 rosetas em campos rupestres e utilizamos regressões lineares para verificar a relação entre o tamanho de corpo e o número de capítulos produzidos pela planta. Nós também comparamos a produção de capítulos entre rosetas isoladas e rosetas pertencentes a clones. Nossos resultados mostram que o tamanho de corpo tem influência positiva significativa na produção de capítulos, mas explica apenas parte da variação nos dados. A produção de capítulos é maior em rosetas pertencentes a clones que em rosetas isoladas. Os clones geralmente apresentam uma roseta, ou um grupo de rosetas, que concentra a reprodução sexual. A clonalidade apresentou ligações significativas com a reprodução sexuada. Em ambientes sazonais a clonalidade pode representar uma importante forma de persistência das plantas já que pode permitir um melhor desempenho da reprodução sexuada em vista dos estresses ambientais. Os casos nos quais a clonalidade representa uma via de melhor desempenho para a reprodução sexuada devem ser considerados e colocados em foco na pesquisa em biologia reprodutiva.(AU)


Assuntos
Eriocaulaceae/anatomia & histologia , Eriocaulaceae/fisiologia , Brasil , Eriocaulaceae/classificação , Flores/crescimento & desenvolvimento , Reprodução/fisiologia , Estações do Ano
20.
Phytopathology ; 104(7): 769-78, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24423403

RESUMO

Citrus crops in São Paulo State, Brazil, have been severely affected by postbloom fruit drop disease (PFD), which is caused by Colletotrichum acutatum. This disease leads to the drop of up to 100% of young fruits. Previous studies have assumed that this pathogen exhibits a clonal reproductive mode, although no population genetic studies have been conducted so far. Thus, the genetic structure of six C. acutatum populations from sweet orange orchards showing PFD symptoms was determined using nine microsatellite markers, enabling inference on predominant mode of reproduction. C. acutatum populations exhibit a nearly panmictic genetic structure and a high degree of admixture, indicating either ongoing contemporary gene flow at a regional scale or a recent introduction from a common source, since this pathogen was introduced in Brazil only very recently. Sharing haplotypes among orchards separated by 400 km suggests the natural dispersal of fungal propagules, with the possible involvement of pollinators. A significant population expansion was detected, which was consistent with an increase in host density associated with crop expansion toward new areas across the state. Findings of moderate to high levels of haplotypic diversity and gametic equilibrium suggest that recombination might play an important role in these pathogen populations, possibly via parasexual reproduction or a cryptic sexual cycle. This study provides additional tools for epidemiological studies of C. acutatum to improve prevention and management strategies for this disease.


Assuntos
Citrus/microbiologia , Colletotrichum/isolamento & purificação , Variação Genética , Doenças das Plantas/microbiologia , Brasil , Análise por Conglomerados , Colletotrichum/genética , DNA Fúngico/química , DNA Fúngico/genética , Demografia , Frutas/microbiologia , Genótipo , Haplótipos , Repetições de Microssatélites/genética , Recombinação Genética , Análise de Sequência de DNA
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