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BACKGROUND AND AIMS: Flower-visitor interactions comprise a continuum of behaviors, from mutualistic partners to antagonistic visitors. Despite being relatively frequent in natural communities, florivory remains unexplored, especially when comprising abiotic factors, spatio-temporal variations and global environmental changes. Here, we addressed the variation of florivory driven by changes in elevation and temporal flower availability. We expect decreased floral resources as elevation increases -due to environmental constraints- which may affect plant-florivore interactions. Yet, if floral resources decrease but florivores remain constant, then we may expect an increase in florivory with increasing elevation in the community. METHODS: The flowering phenology of plant individuals was recorded in the Neotropical campo rupestre vegetation, in southeastern Brazil. Damages by florivores were recorded in plots at elevations ranging from 823 to 1411 m using two response variables as a proxy for florivory: the proportion of attacked flowers per plant and the proportion of petal removal on single flowers. KEY RESULTS: Flower attack increased with elevation and damages were intensified in species with longer flowering periods. Conversely, longer flowering periods resulted in higher levels of petal removal when decreasing elevation. The temporal availability of flowers affected florivory, with the proportion of attacked flowers being more intense when there are less flowered individuals in the community. Petal removal on single flowers was intensified in plots with a larger number of individuals flowering, and with more species co-flowering. CONCLUSIONS: This study brings one of the broadest records of a commonly neglected interaction of insects feeding on floral structures, quantifying the combined effect of floral display and availability along an elevation gradient in a highly biodiverse mountaintop community. These findings contribute to filling in the gap in the understanding of florivory dynamics, focusing on a tropical mountaintop scenario facing imminent environmental changes and excessive natural resource exploitation.
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In a survey of the arthropod fauna of 33 Urban Green Spaces (UGS) in Bogotá, Colombia, between 2017 and 2019, 21 species (3,825 specimens) of Psylloidea were collected. These represent all seven recognised families of jumping plant-lice and include seven species identified only to genus. The specimens, all adults, were collected on 30 plant species used for arborization in the UGS. Two species are described as new (Mastigimaslongicaudatus Rendón-Mera, Burckhardt & Vargas-Fonseca, sp. nov. and Leuronotaalbilinea Rendón-Mera, Burckhardt & Vargas-Fonseca, sp. nov.), one species is redescribed (Mastigimascolombianus Burckhardt, Queiroz & Drohojowska) and one species is recorded for the first time from Colombia (Calindatrinervis Olivares & Burckhardt). Among the seven species identified only to genus is an undescribed species of Melanastera, representing a genus not previously known from Colombia. Fourteen species found during the survey are probably native (66%) and seven (33%) adventive. Our findings highlight the significance of UGS for preservation of biological diversity and stress the importance of using native plants in urban landscape planning for the conservation of the native entomofauna.
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Bermudagrass (Cynodon dactylon (L.) Pers., Poaceae) is one of the most important pasture grasses used in milk production systems in southern Brazil, with an increasing expansion of cultivated areas in recent years. Here, we report the first occurrence of the planthopper Metadelphax propinqua (Fieber) (Hemiptera: Delphacidae) feeding on bermudagrass in Brazil. Population outbreaks of this species were observed in January/February 2023 in a commercial hay production farm in the municipality of Chapecó, Santa Catarina State, southern Brazil. Metadelphax propinqua was found in association with three cultivars of C. dactylon (Tifton 85, Jiggs, and Vaquero). The infested plants showed leaf chlorosis and a reduced plant growth rate due to sap sucking and toxin injection as well as honeydew deposition on the leaves, which led to the development of sooty mold. In addition, this delphacid species has been reported as a vector of important pathogens to bermudagrass species and other row crops. Thus, M. propinqua is a potential pest of bermudagrass in Brazil and should be monitored to assess its establishment and behavior in Brazilian pasturelands.
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Cynodon , Hemípteros , Animales , Brasil , Poaceae , Productos AgrícolasRESUMEN
Herbivorous insects are known to be resistant to fungal endophytes that asymptomatically inhabit plant tissues. The insecticidal ability of the endophytic fungus Aspergillus terreus isolated from Catharanthus roseus against Spodoptera litura (Fabricius) was assessed in the current study. The survival and growth of S. litura were adversely impacted by the ethyl acetate extract of endophytic A. terreus. Fungal extract supplemented diet caused 14 to 94% larval mortality in comparison to 2% in control. Additionally, retarded insect growth was observed after ingestion of supplemented diet. The fungal metabolites were also observed to have an inhibitory influence on the adult emergence and reproductive potential of adults. Phytochemical analysis revealed the presence of phenolic compounds in the crude extract of endophytic fungus which may be responsible for toxicity. It was also determined how endophyte-infected cauliflower plants affected S. litura's survival and growth. Endophyte-infected plants exhibited resistance to S. litura by causing 54% larval mortality and delaying development by 5.2 days. In comparison to uninfected plants, adult emergence, lifespan, fecundity and egg hatchability of insects was significantly decreased on infected plants. There was a significant decrease in relative growth and consumption rates as well as in the efficiency of food conversion, which indicates toxic and antifeedant effect of the fungus on S. litura. This suggests that endophyte-inoculated plants exhibit antibiosis against S. litura. In conclusion, the endophytic fungi having insecticidal activity could be used to develop alternative ecologically safe control strategies.
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Insecticidas , Mariposas Nocturnas , Animales , Spodoptera , Herbivoria , Aspergillus , Larva , Endófitos , Insecticidas/farmacologíaRESUMEN
ABSTRACT Ficus inflorescences host a species-rich chalcid wasp community, including pollinating fig wasps (Agaonidae: Tetrapusinae, Kradibiinae, and Agaoninae) and several species of non-pollinating fig wasps (NPFW), that show several life-history strategies, including gall-inducers, kleptoparasites (i. e. inquilines), and parasitoids. We analyzed the structure and degree of specialization of the fig wasp community associated with Ficus inflorescences in urbanized areas, agroecosystems, and on the edge of forest fragments in the state of Goiás (Brazil). We sampled 34 wasp species in four native Ficus tree species, from which four wasp species occurred in more than one host. Neotropical fig pollinators (Pegoscapus and Tetrapus) were the most abundant species, and they were host-specific, although two pollinator species were associated with Ficus obtusifolia. The Jaccard similarity index was higher in samples of fig wasps collected in the same host, indicating that the community composition was specific to each host species. Community structure indices indicate a specialized structure with low connectance, high bidimensional Shannon H2' and low partner diversity. The communities present a modular web structure in which modules were represented by each host and its associated insect species. These results indicate that the fig wasp communities analyzed are highly specialized, despite a few not strictly host-specific species.
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Calcium oxalate (CaOx) crystals have challenged human curiosity since the advent of microscopy. These crystals are linked to the control of calcium levels in plant cells, but they have also been attributed several other functions, including protection against herbivory. However, the protection offered by CaOx crystals against herbivory may be overstated, as claims have been mainly based on their shapes and hard and indigestible nature rather than on experimental evidence. I contend that it is improbable that a constitutive defense, present since very early in the evolution of plants, has not been superseded by herbivores, especially insects. Here, I present arguments and evidence that suggest that these crystals have low efficiency in protecting plants against herbivores. First, I argue that insects with chewing mouthparts possess a semipermeable structure that protects their midgut, minimizing damage from crystals. Second, the action of CaOx crystals is purely mechanical and similar to other inert materials such as sand. Therefore, CaOx crystals only provide effective protection from herbivory in very particular cases and should not be considered an effective defense without supporting experimental evidence.
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Oxalato de Calcio/química , Herbivoria , Insectos/metabolismo , Plantas/química , Animales , Plantas/parasitologíaRESUMEN
The immune system is considered a functional trait in life-history theory and its modulation is predicted to be costly and highly dependent on the host's nutrition. Therefore, the nutritional status of an individual has a great impact on an animal's immune ecology. Herbivorous insects are commonly used as model organisms in eco-immunology studies and the use of an artificial diet is the predominant rearing procedure to test them. However, this diet differs from what herbivores experience in nature and it is unclear to what degree this distinction might impact on the relevance of these studies for the real world. Here, we compared plant-based vs. artificial diet in a set of three experiments to investigate the interaction of both diets with a plastic immune strategy known as Density-Dependent Prophylaxis (DDP). We used as a model organism the velvetbean caterpillar Anticarsia gemmatalis, which is known to adjust its immune defense in line with the DDP hypothesis. Our main results showed that larvae fed with artificial diet had 20.5% more hemocytes circulating in the hemolymph and died 20% more slowly when infected with an obligate (viral) pathogen. Crucially, however, we did not find any indication of fitness costs related to DDP. The use of artificial diet did not interact with that of DDP except in the case of host survival after infection, where the DDP effect was only observable in this diet. Our findings suggest the use of an artificial diet does not mask resource allocation conflicts between immune investment and fitness related traits, but to some extent it might lead to an overestimation of immune parameters and host survival time after infection. We believe that this is the first study to compare an artificial diet and a host plant covering all these aspects: immune parameters, life-history traits, and host survival after infection. Here we provide evidence that, besides the quantitative effects in immune parameters and host survival time, the use of artificial diet interacts only marginally with a density-dependent immune response. This provides support for the use of artificial diets in eco-immunology studies with insects.
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Abstract Calotropis procera is a xerophytic perennial milkweed shrub native to Asia and Africa, which currently is also widely distributed throughout the Brazilian Caatinga. C. procera is well defended against herbivores, especially with latex and toxic steroidal cardenolides. The goal of this study was to evaluate how patch size of this exotic host plant affect insect herbivory. Eight patches were selected containing a varied number of C. procera individuals (5, 8, 29, 31, 55, 79, 116, and 172 individuals/patch) in the Caatinga. Patches were divided into four categories according to the number of C. procera individuals: very small (5 and 8), small (29 and 31), intermediate (55 and 79), and large (116 and 172). The percentage of herbivory was greater in patch categories with more individuals. Among the herbivorous insects associated with C. procera, larvae of Danaus spp. (Lepidoptera: Nymphalidae) were commonly observed feeding on all patches. These herbivores present specialized behaviors to circumvent the presence of latex on the host leaves. Adult Danaus spp. females probably had higher probability to find large patches of C. procera, leaving a greater abundance of eggs and, consequently, increasing the herbivory by their larvae in these patches. In contrast to immigration tendency, emigration from large patches may be lower, because there is a higher probability of finding resources (e. g. suitable C. procera leaves) inside large patches compared with small patches. We conclude that patch size of the host plant C. procera is a major factor affecting herbivory.
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Abstract We report the first known infestation of mangroves by the invasive moth Hyblaea puera in Paraná, Southern Brazil. The infestation caused massive defoliation of Avicennia schaueriana trees, affecting approximately 20,000 hectares of mangroves. We discuss the implications for conservation and management, focusing on protected areas, the ecology of mangroves, and local livelihoods.
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Cuarentena/métodos , Ecosistema , Plantas , Brasil , Mariposas NocturnasRESUMEN
Abstract Galls are structures produced by plants in response to the activity of several types of organisms. Gall-inducing species have a close relationship with their host plant, as their habitat is largely restricted to the gall and the plant organ in which it develops. All plant organs are susceptible to gall induction by insects, the leaves being the most vulnerable. Knowledge about interactions between gall-inducing insects and plants is fragmented and incomplete in Argentina. In this study, we completed an inventory of galls induced by insects on plants in Córdoba (central Argentina) using information from field surveys and a review of the literature. We also focused on the frequency of plant-insect taxonomic associations and plant organs most commonly attacked by gall-inducing insects. Field surveys were performed systematically in 26 sites of Chaco Serrano, which were visited five times in two consecutive years, and in 17 sites of the province, which were sampled one or two times each. A comprehensive literature search of electronic and conventional databases was also conducted to complete the inventory. A total of 99 gall morphospecies on 58 plant species (21 families and 44 genera) were recorded through both field surveys and a literature review, enlarging the list of species available for the region by almost 50 %. Asteraceae and Fabaceae were the plant families most attacked by galling insects, in partial concordance with the most species-rich plant families in the region. Diptera, particularly the family Cecidomyiidae, was the most species-rich group in the community of galling insects, which is in agreement with different studies across the globe. Baccharis was the genus displaying the highest number of gall morphotypes, followed by Acacia, Condalia, Geoffroea, Prosopis and Schinus. Almost 60 % of the morphotypes were stem galls, a pattern uncommon in the literature. Fusiform and globoid-shaped galls were predominant. Our study highlights the scarce knowledge there is about the interactions between plants and gall-inducing insects in Argentina, particularly those involving species of Cecidomyiidae, with more than 30 undescribed species. Possible mechanisms involved in the predominance of stem galls in central Argentina are discussed. Rev. Biol. Trop. 66(3): 1135-1148. Epub 2018 September 01.
Resumen Las agallas son estructuras producidas por las plantas en respuesta a la actividad de diversos tipos de organismos, los cuales establecen una estrecha relación con sus especies hospedantes, ya que su hábitat está restringido en gran medida a la agalla y al órgano vegetal donde la agalla se desarrolla. Todos los órganos vegetales son susceptibles a la inducción de agallas por insectos, siendo las hojas los más frecuentemente atacados. En Argentina, el conocimiento de estas interacciones es fragmentando e incompleto. En el presente estudio, se realizó un inventario de agallas inducidas por insectos utilizando información obtenida de muestreos a campo y revisión bibliográfica. También nos enfocamos en las asociaciones taxonómicas insecto-planta más frecuentes y en los órganos vegetales más atacados por los insectos cecidógenos. Se realizaron muestreos a campo en 26 sitios localizados en el Chaco Serrano, que fueron visitados cinco veces en dos años consecutivos y en otros 17 sitios, distribuidos en la provincia de Córdoba, que fueron visitados una o dos veces. Además se realizó una exhaustiva revisión bibliográfica en bases de datos electrónicas (disponibles en internet) y convencionales. Un total de 99 agallas en 58 especies vegetales (21 familias y 44 géneros) fueron registradas a través de los muestreos en el campo y la revisión bibliográfica, ampliando el número de interacciones previamente conocidas en al menos un 50 %. Las familias vegetales más atacadas fueron Asteraceae y Fabaceae, coincidiendo con las familias vegetales más diversas de la región. La familia Cecidomyiidae (Diptera) presentó el mayor número de especies, en concordancia con diversos estudios alrededor del mundo. Baccharis fue el género vegetal que mayor número de morfotipos de agallas albergó, seguido por Acacia, Condalia, Geoffroea, Prosopis y Schinus. Al menos el 60 % de morfotipos registrados se presentaron en tallos, un patrón poco común en la bibliografía. Las formas predominantes fueron fusiforme y globoide. Nuestra investigación revela el escaso conocimiento sobre la comunidad de insectos cecidógenos y sus agallas en Argentina, particularmente de las inducidas por especies de la familia Cecidomyiidae, con más de 30 especies aún no descritas. Se discuten posibles mecanismos involucrados en la predominancia de agallas caulinares en el centro de Argentina.
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Animales , Tumores de Planta/estadística & datos numéricos , Asteraceae/crecimiento & desarrollo , Dípteros/anatomía & histología , Dípteros/crecimiento & desarrollo , Insectos , Fabaceae/crecimiento & desarrollo , ArgentinaRESUMEN
ABSTRACT The Parque Nacional do Itatiaia (PNI) (Brazilian Southeast Region) was surveyed monthly for insect galls from February/2014 to December/ 2015. A total of 432 gall morphotypes were found. This number places the PNI as the richest Atlantic forest area in number of gall morphotypes. The galls were found on 47 plant families. Among them, Asteraceae were pointed out as the superhost. The gall richness in the lower part of the PNI is higher than that of the plateau. The insect galls were found in 154 native, 56 endemic and only one exotic plant species. Concerning the conservational status, the host plants include two vulnerable species with three morphotypes together. Several new botanical records were reported. Leaves were the most galled plant organ, followed by stems. Globoid, green, glabrous and one-chambered galls were the most frequent. Cecidomyiidae were the most common gallers. Parasitoids, successors and inquilines composed the associated fauna.
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Animales , Tumores de Planta/parasitología , Plantas/parasitología , Insectos/clasificación , Tumores de Planta/estadística & datos numéricos , Plantas/clasificación , Brasil , Bosques , Interacciones Huésped-ParásitosRESUMEN
We studied Spodoptera frugiperda development using different food sources in the laboratory and field. Newly hatched larvae were fed soybean, cotton, maize, wheat, and oat leaves. An artificial diet was used as the control. Duration of pre-pupal, pupal, and larva-adult period, pupal weight, sex ratio, survival, larva feeding preferences, oviposition preferences, and nutritional quality of different hosts were evaluated. Insects fed on wheat showed the shortest larva-adult period. The insects fed on cotton and soybean had longer larval development cycles and pupae of lower weight. Feeding preference was evident for third instar larvae and did not differ between wheat, oat, maize, and soybean, which were the preferred hosts. Moths oviposited to a greater extent on the upper canopy of wheat than that of other plants in both the no-choice and free-choice tests. Treatments influenced insect growth, food consumption, and digestion when nutritional variables were analyzed. Thus, grasses were better hosts for S. frugiperda development. Cotton was the least preferred food, followed by soybean. The present study can improve our understanding of S. frugiperda in these different crops and help in developing management strategies. Even though S. frugiperda is considered to be polyphagous, this pest is closely associated with grasses (maize, wheat, oat) and has lower potential as a soybean or cotton feeder. Howerver, S. frugiperda food intake regulation appears to be triggered by a complex of different mechanisms. Thus, S. frugiperda can also damage soybean and cotton and adapt to them in the absence of preferred hosts.
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Animales , Alimentos , Fenómenos Fisiológicos Nutricionales de los Animales , Spodoptera , Ciencias de la Nutrición Animal , Conducta Alimentaria , Entomología , InsectosRESUMEN
We studied Spodoptera frugiperda development using different food sources in the laboratory and field. Newly hatched larvae were fed soybean, cotton, maize, wheat, and oat leaves. An artificial diet was used as the control. Duration of pre-pupal, pupal, and larva-adult period, pupal weight, sex ratio, survival, larva feeding preferences, oviposition preferences, and nutritional quality of different hosts were evaluated. Insects fed on wheat showed the shortest larva-adult period. The insects fed on cotton and soybean had longer larval development cycles and pupae of lower weight. Feeding preference was evident for third instar larvae and did not differ between wheat, oat, maize, and soybean, which were the preferred hosts. Moths oviposited to a greater extent on the upper canopy of wheat than that of other plants in both the no-choice and free-choice tests. Treatments influenced insect growth, food consumption, and digestion when nutritional variables were analyzed. Thus, grasses were better hosts for S. frugiperda development. Cotton was the least preferred food, followed by soybean. The present study can improve our understanding of S. frugiperda in these different crops and help in developing management strategies. Even though S. frugiperda is considered to be polyphagous, this pest is closely associated with grasses (maize, wheat, oat) and has lower potential as a soybean or cotton feeder. Howerver, S. frugiperda food intake regulation appears to be triggered by a complex of different mechanisms. Thus, S. frugiperda can also damage soybean and cotton and adapt to them in the absence of preferred hosts.(AU)
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Animales , Spodoptera , Fenómenos Fisiológicos Nutricionales de los Animales , Alimentos , Insectos , Ciencias de la Nutrición Animal , Entomología , Conducta AlimentariaRESUMEN
Gall inducers use these structures as shelters and sources of nutrition. Consequently, they cause multiple physiological changes in host plants. We studied the impact caused by seed coat galls of a braconid wasp on the performance of fruits, seeds and seedlings of tree Inga laurina. We tested whether these seed galls are 'nutrient sinks' with respect to the fruit/seed of host plant, and so constrain the reproductive ability and reduce seedling longevity. We measured the influence of such galls on the secondary compounds, fruit and seed parameters, seed viability and germination and seedling performance. Inga laurina has indehiscent legumes with polyembryonic seeds surrounded by a fleshy sarcotesta rich in sugars. The galls formed inside the seed coat and galled tissues presented higher phenol concentrations, around 7-fold that of ungalled tissues. Galls caused a significant reduction in parameters such as fruit and seed size, seed weight and the number of embryos. Fluctuating asymmetry (a stress indicator) was 31% higher in leaves of galled seed plants in comparison to ungalled seed plants. However, the negative effects on fruit and seed parameters were not sufficient to reduce seed germination (except the synchronization index) or seedling performance (except leaf area and chlorophyll content). We attributed these results to the ability of I. laurina to tolerate gall attack on seeds without a marked influence on seedling performance. Moreover, because of the intensity of seed galling on host plant, we suggest that polyembryony may play a role in I. laurina reproduction increasing tolerance to seed damage.
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Fabaceae/fisiología , Avispas/fisiología , Animales , Fabaceae/citología , Fabaceae/parasitología , Frutas/citología , Frutas/parasitología , Frutas/fisiología , Germinación , Hojas de la Planta/citología , Hojas de la Planta/parasitología , Hojas de la Planta/fisiología , Plantones/citología , Plantones/parasitología , Plantones/fisiología , Semillas/citología , Semillas/parasitología , Semillas/fisiología , ÁrbolesRESUMEN
Abstract:Food web studies, which include qualitative and quantitative information about species interactions for all trophic levels in a specific community, are important tools to characterize the community structure, and to understand the role of species interaction in natural communities. With this aim, we collected fruits of Senegalia tenuifolia from a total of nine sites from three different areas in Minas Gerais, from June to August 2011. Fruits were collected and taken to the laboratory in special containers, to allow insect development and description. And then, we characterized the food web of insects associated with these seeds, and described interactions between these organisms and the host plant, and assessed the impact of insect attacks on seed germination with an experiment under controlled conditions. Additionally, we estimated the available NPK content and the Carbon:Nitrogen ratio in both fruits and seeds. In S. tenuifolia seeds, we have found 937 associated insects of 15 species structured in four trophic levels. We found two Bruchinae seed-feeders species: Merobruchus terani and Stator maculatopygus. We also have observed the seed-feeding hymenopteran species Allorhogas sp. 1 and Prodecatoma sp. 1, and hymenopteran parasitoids species such as Eupelmus sp.1, Lyrcus sp.1, Eurytoma sp.1, Horismenu s sp.1, Chelonus sp.1, Aprostocetus sp.1, Eiphosoma sp.1 and an unidentified Pteromalinae. Considering quantitative food web metrics, our data have suggested low values of generality and high values of trophic vulnerability, besides others, which demonstrated how species interactions are specialized. The impact of seed-feeding insects on seeds was found severe and prevented their germination. Lastly, seeds contained higher NPK content than fruits. In conclusion, the seed predation food web supported by S. tenuifolia has depicted two different features: specialized species interactions, considering parasitoids and seed-feeding species, and, generalized species interactions, considering host-plant and seed-feeding species. Indeed, seeds are resources with high nutrient concentration supporting a rich and complex food web. Finally, S. tenuifolia seeds are directly impacted by seed-feeding insects, preventing them from germination, which could result in a negative effect on host-plant population.
Resumen:Estudios de redes alimentarias, que incluyen información cualitativa y cuantitativa sobre las interacciones entre especies para todos los niveles tróficos en una comunidad específica, son herramientas importantes para caracterizar la estructura de la comunidad, y para comprender el papel de la interacción de las especies en las comunidades naturales. Con este objetivo, se recolectaron frutos de Senegalia tenuifolia de un total de nueve sitios de tres áreas diferentes, en Minas Gerais, entre junio y agosto 2011. Los frutos fueron recolectados y llevados al laboratorio en contenedores especiales, para permitir el desarrollo y descripción del insecto. Luego, se caracterizó la red alimentaria de los insectos asociados a estas semillas, se describieron las interacciones entre estos organismos y la planta hospedera, y se evaluó el impacto del ataque de insectos en la germinación de semillas mediante un experimento en condiciones controladas. Además, se estimó el contenido de NPK y la relación carbono:nitrógeno en frutos y en semillas. En semillas de S. tenuifolia, se encontraron 937 insectos de 15 especies estructuradas en cuatro niveles tróficos. Se encontraron dos especies de Bruchinae que se alimentan de semillas: Merobruchus terani y Stator maculatopygus. También se observaron especies de himenópteros que se alimentan de semillas: Allorhogas sp. 1 y Prodecatoma sp. 1, y especies de himenópteros parasitoides como: Eupelmus sp.1, Lyrcus sp.1, Eurytoma sp.1, Horismenus sp.1, Chelonus sp.1, Aprostocetus sp.1, Eiphosoma sp.1 y un Pteromalinae no identificado. Nuestros datos sugieren valores bajos de generalidad trófica y valores altos de vulnerabilidad trófica, además de otros, lo que demuestra cómo las interacciones entre especies son especializadas. El impacto en las semillas de los insectos que se alimentan de estas es severo e impidió su germinación. Por último, las semillas tenían un mayor contenido de NPK que los frutos. En conclusión, la red alimentaria de depredación de semillas con S. tenuifolia tiene dos características: interacciones de especies especializadas, considerando parasitoides y especies comedoras de semillas, e interacciones generalizadas entre especies, teniendo en cuenta la planta hospedera y las especies comedoras de semillas. De hecho, las semillas son recursos con alta concentración de nutrientes que proveen una rica y compleja red trófica. Por último, las semillas de S. tenuifolia se ven directamente afectadas por los insectos que se alimentan de semillas, que les impide la germinación, lo que podría resultar en un efecto negativo en la población planta-hospedero.
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Conducta Predatoria , Germinación/fisiología , Insectos/clasificación , Fabaceae/anatomía & histología , Plantas/clasificaciónRESUMEN
Japanagromyza inferna Spencer is recorded for the first time from Brazil, in the North coast of the State of Rio de Janeiro, inducing galls in Centrosema virginianum L. (Fabaceae). The species is redescribed, with illustrations of male and female terminalia. A key to the identification of the Neotropical species of Japanagromyza Sasakawa is presented.
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BACKGROUND AND AIMS: Trichomes are epidermal outgrowths generally associated with protection against herbivores and/or desiccation that are widely distributed from ferns to angiosperms. Patterns of topological variation and morphological evolution of trichomes are still scarce in the literature, preventing valid comparisons across taxa. This study integrates detailed morphoanatomical data and the evolutionary history of the tribe Bignonieae (Bignoniaceae) in order to gain a better understanding of current diversity and evolution of trichome types. METHODS: Two sampling schemes were used to characterize trichome types: (1) macromorphological characterization of all 105 species currently included in Bignonieae; and (2) micromorphological characterization of 16 selected species. Individual trichome morphotypes were coded as binary in each vegetative plant part, and trichome density and size were coded as multistate. Ancestral character state reconstructions were conducted using maximum likelihood (ML) assumptions. KEY RESULTS: Two main functional trichome categories were found: non-glandular and glandular. In glandular trichomes, three morphotypes were recognized: peltate (Pg), stipitate (Sg) and patelliform/cupular (P/Cg) trichomes. Non-glandular trichomes were uniseriate, uni- or multicellular and simple or branched. Pg and P/Cg trichomes were multicellular and non-vascularized with three clearly distinct cell layers. Sg trichomes were multicellular, uniseriate and long-stalked. ML ancestral character state reconstructions suggested that the most recent common ancestor (MRCA) of Bignonieae probably had non-glandular, Pg and P/Cg trichomes, with each trichome type presenting alternative histories of appearance on the different plant parts. For example, the MRCA of Bignonieae probably had non-glandular trichomes on the stems, prophylls, petiole, petiolule and leaflet veins while P/Cg trichomes were restricted to leaflet blades. Sg trichomes were not present in the MRCA of Bignonieae independently of the position of these trichomes. These trichomes had at least eight independent origins in tribe. CONCLUSIONS: The patterns of trichome evolution indicate that most morphotypes are probably homologous in Bignonieae and could be treated under the same name based on its morphological similarity and common evolutionary history, in spite of the plethora of names that have been previously designated in the literature. The trichome descriptions presented here will facilitate comparisons across taxa, allowing inferences on the relationsthips between trichome variants and future studies about their functional properties.
Asunto(s)
Bignoniaceae/anatomía & histología , Evolución Biológica , Tricomas/anatomía & histología , Clima Tropical , Bignoniaceae/ultraestructura , Funciones de Verosimilitud , Filogenia , Tricomas/ultraestructuraRESUMEN
Entomofauna associated to fruits and seeds of two species of Enterolobium Mart. (Leguminosae): Harm or benefit? The aims of the present study were to identify the entomofauna associated to the fruits and seeds of Enterolobium contortisiliquum (Vell.) Morong and Enterolobium timbouva Mart. (Leguminosae), as well as to determine relationships among insects and the possible harm and/or benefit stemming from these associations. Fruit infestation was evaluated and the insects were identified. Seed consumption (%) and the germination of predated seeds (%) were determined. The fruits of E. contortisiliquum exhibited a high percentage of infestation (91%). The most representative species in the fruits were Lophopoeum timbouvae Lameere, 1884, Merobruchus bicoloripes (Pic, 1930) and Stator limbatus (Horn, 1873). In the fruits of E. timbouva, only one species was found (S. limbatus). E. contortisiliquum seed consumption was proportionately higher (55.2%) to that of E. timbouva (15%). The germination of predated seeds from E. contortisiliquum was null, whereas 40% of predated seeds from E. timbouva germinated.
RESUMEN
Fragmentos urbanos de mata, como parques e praças, oferecem recursos alimentares, sobretudo abrigo e condições favoráveis para a permanência de borboletas. Este estudo fornece um inventário de borboletas e também a observação das plantas visitadas por indivíduos adultos em um pequeno parque urbano, Parque Municipal Américo Renê Giannetti, Belo Horizonte, estado de Minas Gerais. Amostrou-se uma área de 18,2 ha no período de dezembro/2006 à dezembro/2007, com o auxilio de rede entomológica e armadilhas com frutos fermentados. Foram registrados 165 indivíduos de 78 espécies, distribuídos nas seguintes famílias: Nymphalidae - 46 spp., Hesperiidae - 10 spp., Lycaenidae - sete spp., Pieridae - sete spp., Riodinidae - cinco spp. e Papilionidae - três spp. Entre as plantas visitadas observou-se que a com maior atratividade foi Lantana camara (Verbenaceae), um arbusto com flores de cores vibrantes, destacada como fonte usual de néctar e pólen. As borboletas encontradas indicaram a importância da manutenção de áreas verdes urbanas, proporcionando condições favoráveis para a permanência de borboletas, mesmo em ambientes antrópicos.
Urban forest fragments, such as parks and squares provide food resources, shelter, and favorable conditions for the maintenance of butterflies. This study provides an inventory of butterflies and observations of plants visited by adults in a small urban park, the Américo Renê Giannetti Municipal city park, Belo Horizonte, Minas Gerais State. We sampled an area of 18.2 ha from December 2006 to December 2007 with entomological net and traps baited with fermented fruits. We recorded 165 individuals belonging to 78 species, as follows: 46 spp. of Nymphalidae; 10 spp. of Hesperiidae, seven spp. of Lycaenidae, seven spp. of Pieridae, five spp. of Riodinidae; and three species of Papilionidae. Between the plants visited the more attractive was Lantana camara (Verbenaceae), a shrub with flowers of vibrant colors and common source of nectar and pollen. The butterflies recorded show the importance of maintenance of urban green areas, providing favorable conditions for the permanence of butterflies, even in anthropic environments.
RESUMEN
This study evaluated the parasitoid-aphid-plant associations in Brazil with the objective of developing a useful research database for further studies of aphid parasitoid ecology and aphid management. The original material was obtained from collections made in Paraná, Rio Grande do Sul, Minas Gerais, and São Paulo states. The published information on the Aphidiinae in Brazil is revised. The general features of the target parasitoid fauna of Central and South America is summarized and promising biological control programs of some aphid species in Brazil is discussed.
Este trabalho avaliou as interações parasitóides-pulgão-planta no Brasil, com o objetivo de desenvolver um banco útil de dados para estudos subseqüentes em ecologia de parasitóides de afídeos e manejo de pulgões. O material original foi obtido de coletas nos estados do Paraná, Rio Grande do Sul, Minas Gerais e São Paulo, sendo revisadas as informações sobre Aphidiinae publicadas no Brasil. Foram também sumarizadas as caracteristicas gerais da fauna de parasitóides das Américas Central e do Sul e discutidos os programas potenciais de controle biológico de algumas espécies de pulgões no Brasil.