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1.
Neotrop Entomol ; 53(4): 854-867, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38958916

RESUMO

The genus Anastrepha contains some of the most important fruit pests in the Americas. It comprises more than 300 species, of which 129 occur in Brazil. The genus is divided into 26 species groups, including the pseudoparallela group with 31 species, whose known host plants are primarily fruits of the genus Passiflora (Passifloraceae). Fourteen species are recorded in Brazil. Here, a new species of Anastrepha reared from fruits of Passiflora actinia Hook. and Passiflora elegans Mast. from southern Brazil is described and illustrated. In addition, a synopsis of the Brazilian species of the pseudoparallela group is provided.


Assuntos
Tephritidae , Animais , Brasil , Tephritidae/classificação , Masculino , Feminino , Passiflora/parasitologia , Frutas/parasitologia
4.
Micron ; 109: 11-21, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29609093

RESUMO

Lepidopteran species present an interesting case of sperm polymorphism and testicular fusion. The study of these features are of great importance in understanding the reproductive biology of these insects, especially in the case of those considered pests. Dione juno and Agraulis vanillae stand out as the most important pests of passion fruit (Passiflora sp.) crops in Brazil. Therefore, the objective of the present study was to characterize the testes and germ cells of Dione juno and Agraulis vanillae at different life stages, using light microscopy and scanning and transmission electron microscopy, to understand the maturation mechanisms of the male gametes in these species. The study showed that the larvae of both species have a pair of brown kidney-shaped testes, covered by epithelial cells which divide the organ into four follicles. The testes are full of spermatogonia which begin to differentiate in the third larval instar. In the fifth larval instar, spermatozoa can be observed. When they enter the prepupal stage the testes begin a fusion process that is completed in the adult insects, where they present as spherical organs divided into eight follicles, containing all the cells of the germ line. Spermatogenesis occurs centripetally, and in both species, sperm dimorphism is observed, where two different types of spermatozoa are formed, eupyrene (nucleated) and apyrene (anucleate), which differ in morphology and function. Apart from contributing to scientific basic research on the reproductive biology of these insects, the present study provides important data that can aid in research on the physiology, systematics, and control of these species.


Assuntos
Borboletas , Espermatogênese/fisiologia , Espermatogônias/citologia , Testículo/anatomia & histologia , Testículo/ultraestrutura , Animais , Brasil , Borboletas/anatomia & histologia , Borboletas/fisiologia , Borboletas/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Passiflora/parasitologia
5.
J Econ Entomol ; 108(1): 201-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26470121

RESUMO

Yellow passionfruit (Passiflora edulis f. flavicarpa O. Deg.) is a tropical fruit crop that is meeting increasing demand both in local and international markets in South America. The lance fly, Dasiops inedulis (Diptera: Lonchaeidae), affects P. edulis floral buds and flowers, and is thought to cause important yield losses in this crop. In Colombia, D. inedulis are commonly controlled through calendar-based applications of chemically synthesized insecticides, and no scientific criteria exist to guide pest management. In the present study, we simulated D. inedulis injury to passionfruit plants, over the course of three production cycles. We assessed the effect of seven different categories of flower bud removal (from 0% to 79.9%) on passionfruit yield and fruit quality parameters. Removal rates above 20% caused a significant reduction in the number of flowers, while yield levels were lowest at 50-79.9% bud removal. With increasing rates of flower bud removal, we observed higher initial production of buds and lower levels of natural abortion of floral and fruiting structures. For the three consecutive harvests, maximum yield levels were 7.57±5.51 kg (mean±SD; with 0-9.9% damage), and minimum yield was 2.37±2.15 kg (60-69.9% damage) per plant. For fruit quality parameters, D. inedulis injury did not affect fruit pulp weight or the content of soluble solids (Brix). Our work provides insights into the impact of D. inedulis on yellow passionfruit production, and constitutes a basis for future integrated pest management programs for this pest.


Assuntos
Dípteros/fisiologia , Passiflora/parasitologia , Animais , Biomassa , Frutas/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Passiflora/crescimento & desenvolvimento
6.
J Evol Biol ; 26(9): 1959-67, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23961921

RESUMO

Shifts in host-plant use by phytophagous insects have played a central role in their diversification. Evolving host-use strategies will reflect a trade-off between selection pressures. The ecological niche of herbivorous insects is partitioned along several dimensions, and if populations remain in contact, recombination will break down associations between relevant loci. As such, genetic architecture can profoundly affect the coordinated divergence of traits and subsequently the ability to exploit novel habitats. The closely related species Heliconius cydno and H. melpomene differ in mimetic colour pattern, habitat and host-plant use. We investigate the selection pressures and genetic basis underlying host-use differences in these two species. Host-plant surveys reveal that H. melpomene specializes on a single species of Passiflora. This is also true for the majority of other Heliconius species in secondary growth forest at our study site, as expected under a model of interspecific competition. In contrast, H. cydno, which uses closed-forest habitats where both Heliconius and Passiflora are less common, appears not to be restricted by competition and uses a broad selection of the available Passiflora. However, other selection pressures are likely involved, and field experiments reveal that early larval survival of both butterfly species is highest on Passiflora menispermifolia, but most markedly so for H. melpomene, the specialist on that host. Finally, we demonstrate an association between host-plant acceptance and colour pattern amongst interspecific hybrids, suggesting that major loci underlying these important ecological traits are physically linked in the genome. Together, our results reveal ecological and genetic associations between shifts in habitat, host use and mimetic colour pattern that have likely facilitated both speciation and coexistence.


Assuntos
Borboletas/genética , Comportamento Competitivo/fisiologia , Ecossistema , Passiflora/parasitologia , Pigmentação/fisiologia , Seleção Genética , Animais , Borboletas/fisiologia , Estudos de Associação Genética , Larva/fisiologia , Panamá , Especificidade da Espécie , Análise de Sobrevida
7.
Neotrop Entomol ; 39(2): 306-7, 2010.
Artigo em Português | MEDLINE | ID: mdl-20498972

RESUMO

We describe the new association of Hexacladia smithii (Ashmead) parasitizing two passion fruit bugs, Holhymenia histrio (Fabricius) and Anisoscelis foliacea marginella (Dallas) (Hemiptera: Coreidae), in Brazil.


Assuntos
Himenópteros/parasitologia , Passiflora/parasitologia , Animais , Brasil
8.
Neotrop. entomol ; 39(2): 306-307, mar.-abr. 2010.
Artigo em Português | LILACS | ID: lil-547696

RESUMO

We describe the new association of Hexacladia smithii (Ashmead) parasitizing two passion fruit bugs, Holhymenia histrio (Fabricius) and Anisoscelis foliacea marginella (Dallas) (Hemiptera: Coreidae), in Brazil.


Assuntos
Animais , Himenópteros/parasitologia , Passiflora/parasitologia , Brasil
9.
Neotrop. entomol ; 37(6): 744-746, Nov.-Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-507037

RESUMO

This note is the first report of Bemisia tabaci (Gennadius) biotype B colonizing passionvine in Brazil. We examined the colonization of nine Passiflora species by a wild B type population under greenhouse conditions. P. amethystina Mikan was the most preferred species for oviposition and colonization, whereas P. suberosa L., P. coriacea Juss. and two commercially cultivated species, P. alata Curtis and P. edulis Sims f. flavicarpa Degener, were mostly uncolonised. P. morifolia Mast., P. cincinnata Mast., P. foetida L. and P. caerulea L. showed intermediate levels of colonization. Such differential colonization might suggest some degree of resistance by certain Passiflora species or oviposition preference by B. tabaci.


Esse trabalho descreve pela primeira vez a ocorrência do aleirodídeo Bemisia tabaci (Gennadius) biótipo B colonizando maracujazeiros no Brasil. Também foi examinada a colonização de nove espécies de Passiflora pelo inseto em condições de telado. P. amethystina Mikan foi a espécie de maior preferência para oviposição e colonização, enquanto P. suberosa L., P. coriacea Juss. e duas espécies cultivadas comercialmente, P. alata Curtis e P. edulis Sims f. flavicarpa Degener, foram pouco colonizadas pelo aleirodídeo. P. morifolia Mast., P. cincinnata Mast., P. foetida L. e P. caerulea L. exibiram níveis intermediários de colonização. Esses resultados sugerem que certas espécies de Passiflora exibem diferentes graus de resistência à colonização ou preferência para oviposição de B. tabaci biótipo B.


Assuntos
Animais , Hemípteros/fisiologia , Passiflora/parasitologia , Brasil
10.
Environ Entomol ; 37(5): 1323-31, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19036213

RESUMO

The interactions of Holymenia clavigera (Herbst) and Anisoscelis foliacea marginella (Dallas) with their hosts (Passifloraceae) in southern Brazil are poorly understood. Previous studies have indicated that both species use several host species and plant parts and have superior performance on wild hosts. This study evaluated feeding preferences and host plant use under both laboratory and field conditions. Choice tests were performed to determine preference for Passiflora suberosa parts, preference for P. suberosa and Passiflora misera immature and ripe fruits, and preference for P. suberosa, P. misera, and Passiflora edulis shoots. A field survey was carried out to assess H. clavigera and A. foliacea marginella use of P. suberosa parts. In addition, immature and ripe fruits of P. suberosa and P. misera were characterized in relation to pH, phenols, and anthocyanins. First-instar nymphs preferred the terminal buds, shifting to immature fruits in the second instar. Both coreids more frequently fed on immature fruits than on ripe ones. Neither species showed a significant preference among host species. The immature fruits presented higher phenol content as compared with the ripe fruits; the opposite was observed for anthocyanins. In the field, immature fruits and mature leaves were selected for feeding and resting. Thus, this study confirms the food mixing condition of these coreids, as well as the importance of fruits for their nutrition. Phenols, and presumably water, in the fruits may play a role in their feeding choices.


Assuntos
Preferências Alimentares , Frutas/parasitologia , Heterópteros/fisiologia , Interações Hospedeiro-Parasita , Passiflora/parasitologia , Animais , Antocianinas/análise , Frutas/química , Concentração de Íons de Hidrogênio , Fenóis/análise , Especificidade da Espécie
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