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1.
Neotrop Entomol ; 48(3): 433-448, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30515720

RESUMO

Spodoptera marima (Schaus, 1904) and Spodoptera ornithogalli (Guenée, 1852) are noctuid moths recognized for their economic importance in the New World. Historically, they have been considered cryptic species, being supposedly differentiated from each other by the absence of sexual dimorphism in S. marima, subtle differences in coloration on the hindwings and scale tufts of the ovipositor and the shape of male valva. The species are allopatric: North and Central America for S. ornithogalli and South America for S. marima. Previous phylogenetic studies using multilocus DNA sequences including a few specimens of S. marima suggested these species merge into a single clade. Here, we performed a comparative analysis to elucidate further their taxonomic status, using specimens of S. marima from various localities in Brazil. These species were recovered in the phylogenetic analysis as consistently mixed with each other in a major well-supported clade within Spodoptera. The existence of a spatial pattern for genetic structure was not clearly supported when two biogeographic regions (Neotropics and Neartic) were taken in separation; however, an individual-level isolation by distance was significant. The morphological characters traditionally used to differentiate the species were also not consistent. Therefore, we now consider S. marima a new junior synonym of S. ornithogalli. Results on host plant use demonstrated that it is a polyphagous species using more than 200 plants, which may mediate phenotypic variation along its geographical range.


Assuntos
Variação Genética , Spodoptera/genética , Distribuição Animal , Animais , Teorema de Bayes , Brasil , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Genes Mitocondriais , Masculino , América do Norte , Filogenia , América do Sul , Spodoptera/classificação , Asas de Animais/anatomia & histologia
2.
Neotrop Entomol ; 47(1): 85-95, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28332139

RESUMO

Adult foretarsi of Heliconius erato Linnaeus (Lepidoptera, Nymphalidae) are reduced in size and are not used for walking. Foretarsi of the female have specialized sensilla that are presumably used to identify the host plant, by drumming. The mid- and hind tarsi also bear sensilla in both sexes, but these have not been described in detail, nor has their chemosensory function been determined. We described and compared the tarsi of H. erato under light and scanning electron microscopy. Behavioral experiments showed that differences in the shape, number, and size of sensilla were related to feeding and oviposition behaviors. Two types of sensillum (chaeticum and trichodeum) were found in similar numbers and size on the mid- and hind tarsi of both sexes. Sensilla on the female foretarsi act in host-plant site selection, strongly affecting oviposition rates when isolated. Male foretarsi lack sensilla, which may have been selected against due to the absence of function and thus lost. Sensilla on the mid- and hind tarsi are involved in sugar detection in both sexes, responding to an effective dose of sucrose (ED50) near 0.01 M, and therefore might be used to identify food resources when the butterflies settle on flowers.


Assuntos
Borboletas/fisiologia , Comportamento Alimentar , Oviposição , Sensilas/ultraestrutura , Animais , Feminino , Masculino , Microscopia Eletrônica de Varredura , Sacarose
3.
Genet Mol Res ; 15(2)2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27420969

RESUMO

Crespa goats are phenotypically similar to the Angora breed, and are traditionally reared in small, low-tech farms in southernmost Brazil. Whether they represent degenerated remnants of pure Angora goats or result from foreign breeds introduced during colonial times and recently mixed with commercial breeds is unknown. Since the degree of relatedness of Crespa in relation to other goats is completely unknown, we performed a comparative assessment of the genetic similarity between Crespa and foreign commercial breeds reared in the region (Angora, Alpine, Anglo-Nubian, Boer, and Saanen), particularly the Angora. We used 11 microsatellites to score alleles in 148 individuals and performed a Bayesian assignment test, which revealed six clusters (K = 6; Ln likelihood = -5047.6). In addition, a segment of the mitochondrial DNA (mtDNA) control region was sequenced to investigate the relatedness of Crespa goats to Portuguese autochthonous breeds (Algarvia, Bravia, Charnequeira, Serpentina, and Serrana). The origin of the Crespa breed could not be ascertained from the mtDNA, but it does not only descend from the Angora. It is probably related to other introduced and autochthonous Portuguese breeds, in particular the Algarvia. Therefore, our results indicate that this distinctive source of genetic diversity is partly a remnant of animals that were introduced during the colonial period. By recognizing it as genetically distinct, we provide further support for the protection of this particular gene pool.


Assuntos
Cabras/genética , Polimorfismo Genético , Seleção Artificial , Animais , Brasil , DNA Mitocondrial/genética , Pool Gênico , Repetições de Microssatélites
4.
Neotrop Entomol ; 45(3): 336-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26957083

RESUMO

The little-known Neotropical tortricid moth Lasiothyris luminosa (Razowski & Becker) is reported for the first time as a grapevine pest in northeastern Brazil. A diagnosis based on morphological characters including the genitalia is provided for both sexes, together with a preliminary description of economic damage caused by the larval stage on flowers and fruits. In addition, we sequenced a partial region of the cytochrome oxidase subunit I gene from specimens from the region and reconstructed phylogenetic relationships using representative lineages of closely related tortricids as terminals.


Assuntos
Mariposas , Filogenia , Vitis , Animais , Brasil , Feminino , Frutas , Larva , Masculino
5.
Genet Mol Res ; 11(3): 2997-3006, 2012 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-22653672

RESUMO

The melanocortin 1 receptor (MC1R) gene has been described as responsible for the black color in some breeds of sheep, but little is known about its function in many colored breeds, particularly those with a wide range of pigmentation phenotypes. The Brazilian Creole is a local breed of sheep from southern Brazil that has a wide variety of wool colors. We examined the MC1R gene (Extension locus) to search for the e allele and determine its role in controlling wool color variation in this breed. One hundred and twenty-five animals, covering the most common Creole sheep phenotypes (black, brown, dark gray, light gray, and white), were sequenced to detect the mutations p.M73K and p.D121N. Besides these two mutations, three other synonymous sites (429, 600, and 725) were found. The dominant allele (E(D): p.73K, and p.121N) was found only in colored animals, whereas the recessive allele (E⁺: p.73M, and p.121D) was homozygous only in white individuals. We concluded that MC1R is involved in the control of wool color in Brazilian Creole sheep, particularly the dark phenotypes, although a second gene may be involved in the expression of the white phenotype in this breed.


Assuntos
Alelos , Loci Gênicos/genética , Variação Genética , Pigmentação/genética , Receptor Tipo 1 de Melanocortina/genética , Ovinos/genética , Lã/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Brasil , Bovinos , Frequência do Gene/genética , Haplótipos/genética , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 1 de Melanocortina/química
6.
Anim Genet ; 41(3): 308-10, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19917048

RESUMO

Using ND5 sequences from mtDNA and 10 nuclear markers, we investigated the genetic differentiation of two South American Creole sheep phenotypes that historically have been bred in different biomes in southern Brazil. In total, 18 unique mtDNA haplotypes were detected, none of which was shared between the two phenotypes. Bayesian analysis also indicated two different groups (k = 2). Thus, these varieties are supported as being genotypically distinct. This situation could have resulted either from geographical isolation, associated with differences in the cultural habits of sheep farmers and in the way that flocks were managed, or more likely, from the introduction of different stocks four centuries ago.


Assuntos
DNA Mitocondrial/genética , Análise de Sequência de DNA , Carneiro Doméstico/genética , Animais , Teorema de Bayes , Tamanho Corporal , Genética Populacional , Carneiro Doméstico/anatomia & histologia , Carneiro Doméstico/fisiologia
7.
Braz J Biol ; 67(1): 91-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17505754

RESUMO

Holymenia clavigera (Herbst) and Anisoscelis foliacea marginella (Dallas) (Hemiptera: Coreidae: Anisoscelini) are distributed in southern Brazil and use various passion vine species (Passifloraceae) as host-plants. Preliminary observations indicate a high coexistence of these species in terms of host-plant use; in addition, there is a strong similarity regarding egg and nymph morphology. In this study, the most suitable feeding sites for nymph performance on wild (Passiflora suberosa Linnaeus and Passiflora misera Humbold, Bonpland et Kunth) and cultivated (Passiflora edulis Sims) hosts were determined by rearing them on each host and on the combination of hosts. Performance was determined by evaluating nymph development and survivorship, and adult size at emergence. Plant parts used were also recorded. For both species, P. suberosa was the most suitable host plant. First instar nymphs of both species fed on terminal buds more frequently when compared to other plant parts. Second instar nymphs switched to green fruits, whose behavior was more pronounced for H. clavigera. Thus, H. clavigera and A. foliacea marginella immatures are extremely similar in terms of host-plant use and consequences for performance, in addition to their morphological similarity. We suggest that these coreids may have evolved through several processes, including parsimony between the immature stages after speciation, evolutionary convergence, mimicry or genetic drift.


Assuntos
Comportamento Alimentar/fisiologia , Hemípteros/fisiologia , Passiflora/parasitologia , Animais , Feminino , Interações Hospedeiro-Parasita , Masculino , Ninfa/fisiologia
8.
Braz. j. biol ; 67(1): 91-99, Feb. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-449631

RESUMO

Holymenia clavigera (Herbst) and Anisoscelis foliacea marginella (Dallas) (Hemiptera: Coreidae: Anisoscelini) are distributed in southern Brazil and use various passion vine species (Passifloraceae) as host-plants. Preliminary observations indicate a high coexistence of these species in terms of host-plant use; in addition, there is a strong similarity regarding egg and nymph morphology. In this study, the most suitable feeding sites for nymph performance on wild (Passiflora suberosa Linnaeus and Passiflora misera Humbold, Bonpland et Kunth) and cultivated (Passiflora edulis Sims) hosts were determined by rearing them on each host and on the combination of hosts. Performance was determined by evaluating nymph development and survivorship, and adult size at emergence. Plant parts used were also recorded. For both species, P. suberosa was the most suitable host plant. First instar nymphs of both species fed on terminal buds more frequently when compared to other plant parts. Second instar nymphs switched to green fruits, whose behavior was more pronounced for H. clavigera. Thus, H. clavigera and A. foliacea marginella immatures are extremely similar in terms of host-plant use and consequences for performance, in addition to their morphological similarity. We suggest that these coreids may have evolved through several processes, including parsimony between the immature stages after speciation, evolutionary convergence, mimicry or genetic drift.


Holymenia clavigera (Herbst) e Anisoscelis foliacea marginella (Dallas) (Hemiptera: Coreidae: Anisoscelini) ocorrem no sul do Brasil e são hóspedes de diversas espécies de Passifloraceae. Observações preliminares indicam uma alta coexistência destas espécies em termos de uso da planta hospedeira; em adição, ovos e ninfas são extremamente semelhantes. Neste estudo comparou-se a performance das ninfas das duas espécies em passifloráceas nativas silvestres (Passiflora suberosa Linnaeus e Passiflora misera Humbold, Bonpland et Kunth) e cultivadas (Passiflora edulis Sims), oferecidas em separado e conjuntamente. Foram determinadas as taxas de desenvolvimento e mortalidade ninfal, bem como o tamanho do adulto à emergência. As partes das hospedeiras mais utilizadas para alimentação foram registradas. Para ambos os coreídeos, P. suberosa conferiu melhor performance. Ninfas de primeiro instar de ambas as espécies alimentaram-se com maior intensidade da região apical dos ramos quando comparado com as demais partes das plantas. Ambas as espécies mudaram para os frutos verdes no segundo instar, sendo este comportamento mais pronunciado em H. clavigera. Deste modo, além da semelhança morfológica, os imaturos de H. clavigera and A. foliacea marginella são extremamente similares no tangente à interação com suas plantas hospedeiras. Sugere-se que estes coreídeos possam ter evoluído através de vários processos, entre os quais parcimônia entre as fases imaturas após especiação, convergência evolutiva, mimetismo ou deriva genética.


Assuntos
Animais , Masculino , Feminino , Comportamento Alimentar/fisiologia , Hemípteros/fisiologia , Passiflora/parasitologia , Interações Hospedeiro-Parasita , Ninfa/fisiologia
9.
Braz J Biol ; 66(3): 853-62, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17119833

RESUMO

Leaf morphology may vary considerably even within a branch of Passiflora suberosa plants. Leaves are of a typical green type in shaded areas, but in open fields turn into violet, and apparently have greater thickness and trichome density. The proximate causes and the adaptive meaning, if any, for the existence of the violet morph are still unknown. By cultivating P. suberosa clones under two light regimes (total and partial exposure to sunlight), we consecutively induced (first year) and then reversed (second year) the appearance of the violet morph. We evaluated the corresponding changes in morpho-anatomic and chemical leaf characteristics. Plants that were grown under partial sunlight had a greater size and did not alter their green color, but those grown under total sunlight changed into violet, were smaller in size and their leaves were tougher, thicker, and had a greater number of trichomes. The violet morph had increased anthocyanins and phenolic derivatives. It also showed cellular hypertrophy, a greater number of cell layers in the mesophyll, and a lignified pericycle. Since these morphs are interchangeable by changing light conditions, we inferred that they are not determined by genotypic diversity, but are mainly a result of a physiological response to light stress, and thus part of P. suberosa phenotypic plasticity.


Assuntos
Passiflora/anatomia & histologia , Fenótipo , Pigmentação/fisiologia , Folhas de Planta/anatomia & histologia , Luz Solar , Antocianinas/análise , Cromatografia em Papel , Passiflora/química , Passiflora/fisiologia , Fenol/análise , Folhas de Planta/química , Folhas de Planta/fisiologia
10.
Braz. j. biol ; 66(3): 853-862, Aug. 2006. ilus, graf
Artigo em Inglês, Português | LILACS | ID: lil-435626

RESUMO

Leaf morphology may vary considerably even within a branch of Passiflora suberosa plants. Leaves are of a typical green type in shaded areas, but in open fields turn into violet, and apparently have greater thickness and trichome density. The proximate causes and the adaptive meaning, if any, for the existence of the violet morph are still unknown. By cultivating P. suberosa clones under two light regimes (total and partial exposure to sunlight), we consecutively induced (first year) and then reversed (second year) the appearance of the violet morph. We evaluated the corresponding changes in morpho-anatomic and chemical leaf characteristics. Plants that were grown under partial sunlight had a greater size and did not alter their green color, but those grown under total sunlight changed into violet, were smaller in size and their leaves were tougher, thicker, and had a greater number of trichomes. The violet morph had increased anthocyanins and phenolic derivatives. It also showed cellular hypertrophy, a greater number of cell layers in the mesophyll, and a lignified pericycle. Since these morphs are interchangeable by changing light conditions, we inferred that they are not determined by genotypic diversity, but are mainly a result of a physiological response to light stress, and thus part of P. suberosa phenotypic plasticity.


A morfologia das folhas de Passiflora suberosa pode variar consideravelmente mesmo dentro dos ramos de um dado espécime. P. suberosa ocorre tipicamente em áreas sombreadas e as folhas são verdes. Porém, em áreas abertas, onde há maior incidência de luz solar, as folhas são de coloração roxa, aparentemente mais duras e com grande densidade de tricomas. As possíveis causas e o significado adaptativo da manifestação destas características ainda são desconhecidas. Com base no cultivo de clones de P. suberosa sob dois regimes de luz solar (incidência total e parcial), nós consecutivamente induzimos (primeiro ano) e então revertemos (segundo ano) o aparecimento da forma roxa. As mudanças nas características morfológicas e químicas das formas verde e roxa foram avaliadas. As plantas que foram cultivadas sob incidência parcial de luz solar apresentaram maior tamanho dos ramos e não alteraram a cor verde das folhas. As plantas que foram cultivadas sob incidência total dos raios solares apresentaram coloração roxa, maior dureza, espessura e pilosidade. A forma roxa apresentou alto teor de antocianinas e derivados fenólicos. As plantas exibiram hipertrofia celular, maior número de camadas celulares no mesofilo e lignificação do periciclo. Considerando que as formas são intercambiáveis perante a mudança na intensidade luminosa, nós inferimos que elas não resultam da diversidade genotípica, mas sim de uma resposta fisiológica ao estresse luminoso e, dessa forma, parte da plasticidade fenotípica de P. suberosa.


Assuntos
Fenótipo , Passiflora/anatomia & histologia , Pigmentação/fisiologia , Folhas de Planta/anatomia & histologia , Luz Solar , Antocianinas/análise , Cromatografia em Papel , Passiflora/química , Passiflora/fisiologia , Fenol/análise , Folhas de Planta/química , Folhas de Planta/fisiologia
11.
Braz J Biol ; 62(2): 321-32, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12489404

RESUMO

Adult body size, one of the most important life-history components, varies strongly within and between Heliconius erato phyllis (Lepidoptera: Nymphalidae) populations. This study determines if this variation is caused by geographical changes in host-plant used by the larval stage, whose reproductive parameters are influenced by female body size, with estimates of the corresponding heritability. The variation in adult body size was determined together with a survey of passion vine species (Passifloraceae) used by the larvae in seven localities in Rio Grande do Sul State: three located in the urban area of Porto Alegre and Triunfo Counties, two within Eucalyptus plantations (Barba Negra Forest, Barra do Ribeiro County, and Aguas Belas Experimental Station-Viamão County), one in a Myrtaceae Forest (Itapuã State Park-Itapuã County) and one in the Atlantic Rain Forest (Maquiné Experimental Station-Maquiné County). Effects of female body size on fecundity, egg size and egg viability were determined in an outdoor insectary. Size heritability was estimated by rearing in the laboratory offspring of individuals maintained in an insectary. The data showed that adults from populations where larvae feed only upon Passiflora suberosa are smaller than those that feed on Passiflora misera. The larvae prefer P. misera even when the dominant passion vine in a given place is P. suberosa. Fecundity increases linearly with the increase in size of females, but there is no size effect on egg size or viability. Size heritability is null for the adult size range occurring in the field. Thus, the geographical variation of H. erato phyllis adult size is primarily determined by the type, corresponding availability and quality of host-plants used by the larval stage. Within the natural size range of H. erato phyllis, the variation related to this character is not genetically based, thus being part of H. erato phyllis phenotypic plasticity.


Assuntos
Constituição Corporal , Borboletas/anatomia & histologia , Passiflora/parasitologia , Animais , Borboletas/crescimento & desenvolvimento , Borboletas/fisiologia , Comportamento Alimentar , Feminino , Fertilidade , Interações Hospedeiro-Parasita , Larva/fisiologia , Masculino , Oviposição , Características de Residência
12.
Braz. j. biol ; 62(2): 321-332, May 2002. ilus, graf
Artigo em Inglês | LILACS | ID: lil-326203

RESUMO

Adult body size, one of the most important life-history components, varies strongly within and between Heliconius erato phyllis (Lepidoptera: Nymphalidae) populations. This study determines if this variation is caused by geographical changes in host-plant used by the larval stage, whose reproductive parameters are influenced by female body size, with estimates of the corresponding heritability. The variation in adult body size was determined together with a survey of passion vine species (Passifloraceae) used by the larvae in seven localities in Rio Grande do Sul State: three located in the urban area of Porto Alegre and Triunfo Counties, two within Eucalyptus plantations (Barba Negra Forest, Barra do Ribeiro County, and Aguas Belas Experimental Station -- Viamäo County), one in a Myrtaceae Forest (Itapuä State Park -- Itapuä County) and one in the Atlantic Rain Forest (Maquiné Experimental Station -- Maquiné County). Effects of female body size on fecundity, egg size and egg viability were determined in an outdoor insectary. Size heritability was estimated by rearing in the laboratory offspring of individuals maintained in an insectary. The data showed that adults from populations where larvae feed only upon Passiflora suberosa are smaller than those that feed on Passiflora misera. The larvae prefer P. misera even when the dominant passion vine in a given place is P. suberosa. Fecundity increases linearly with the increase in size of females, but there is no size effect on egg size or viability. Size heritability is null for the adult size range occurring in the field. Thus, the geographical variation of H. erato phyllis adult size is primarily determined by the type, corresponding availability and quality of host-plants used by the larval stage. Within the natural size range of H. erato phyllis, the variation related to this caracter is not genetically based, thus being part of H. erato phyllis phenotypic plasticity


Assuntos
Masculino , Feminino , Animais , Constituição Corporal , Borboletas , Passiflora , Borboletas , Comportamento Alimentar , Fertilidade , Interações Hospedeiro-Parasita , Larva , Oviposição , Características de Residência
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