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151.
Paula Daiana De Paulo Eliseu José G. Pereira Eugenio E. Oliveira Alberto Fereres Elisa Garzo 《Journal of Applied Entomology》2020,144(10):941-951
The development of herbivore insects is influenced by the quality of their host plants. Elevated CO2 alters plant metabolism, which may change the nutritional quality of the plant, modifying the life history and feeding behaviour of herbivore insects. Understanding how insect pests respond to increasing CO2 concentration is essential for predicting the impact of the pest on food security. In this study, we investigated the effects of elevated CO2 (eCO2) on the life history and feeding behaviour of the MEAM1 species of Bemisia tabaci on a Bt soybean cultivar. We found that eCO2 increased the egg to adult development time and reduced the reproductive responses (fecundity and fertility) of B. tabaci. The whitefly B. tabaci that fed on the soybean plants grown under eCO2 conditions was negatively influenced by several traits related to the host plant resistance, such as the time spent on phloem sap ingestion. Furthermore, we evaluated the changes in the C:N concentration and plant morphology of the Bt plants. The biomass (weight of leaves and stems) of the Bt soybean plants grown under eCO2 conditions was significantly increased, and the elevated C:N ratio in the phenological stage V6 (i.e. when the plants had six trifoliate leaves developed) was the most pronounced difference in the Bt soybean plants subjected to eCO2 treatment. Taken together, our results indicate that Bt plants cultivated under eCO2 inhibit B. tabaci feeding, which can reduce whitefly infestations of the soybean fields. 相似文献
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Carola Cañón Daiana Mir Ulyses F. J. Pardiñas Enrique P. Lessa Guillermo D'Elía 《Zoologica scripta》2014,43(5):443-454
Abrotrichini is a recently defined and diagnosed tribe of Sigmodontinae with a complex taxonomy. Abrotrichine genera, Abrothrix (including Chroeomys), Chelemys, Geoxus, Notiomys and Pearsonomys, are mostly distributed in the central and southern Andes and adjacent lowlands and show terrestrial and fossorial habits. Recent studies have evidenced some incongruence between current taxonomy and abrotrichine phylogeny, such as the polyphyly of Chelemys and paraphyly of Geoxus respect to Pearsonomys. We used DNA sequence data of six loci (one mitochondrial and five nuclear) to resolve the relationships within the tribe. Independent and combined analyses of these loci were carried out using parsimony, maximum likelihood and Bayesian inference. Estimates of divergence time of the main lineages of abrotrichines were calculated with a molecular clock using as calibration, a fossil recently found. The concatenated data set increased the resolution and defined the relationships within the tribe. Our phylogenetic analyses corroborate that Abrothrix is sister of a clade containing the long‐clawed abrotrichines. We recovered two main clades within Abrothrix that match morphologic variation and geographic distribution of its species. In addition, we corroborated the lack of monophyly of Chelemys and the lack of monophyly of Geoxus. We discuss different taxonomic scenarios to abrotrichine classification reflects the phylogenetic relationships obtained in this study. Our molecular clock estimated the Abrotrichini crown age to be around the early Pliocene (4.4 Ma) and suggest that the tribe diversified over a short period of time. 相似文献
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Carlos Alberto de Sousa Rodrigues-Filho Ronaldo César Gurgel-Lourenço Luis Artur Valões Bezerra Edson Fontes de Oliveira Rafael Pereira Leitão Danielle Sequeira Garcez Jorge Iván Sánchez-Botero 《Hydrobiologia》2018,824(1):93-108
The spread of antibiotic-resistant bacteria is a threatening risk for human health at a global scale. Improved knowledge on the cycle of antibiotic resistance spread between human and the environment is a major requirement for the management of the current crisis. Compared to the well-studied cycle in clinical settings much less is known about the factor allowing their persistence in the environment. In fact, lakes and rivers exposed to high anthropogenic impact seem to become long-term reservoirs for resistance genes. The presence of antibiotic resistance genes (ARGs) within the resident microbiome of large subalpine lakes (i.e. Lake Geneva, Lake Maggiore) has recently been investigated in both the water column and the sediment. These studies suggest a correlation between the abundance of some ARGs and the anthropogenic impact. Within the system, however, abiotic factors and the food-web structure determine the survival of specific bacterial genotypes and thus the resistance genes they harbour. Thus, a growing body of work suggests an important role of ecological interactions in the persistence or elimination of such genes from the environment. This article reviews the current literature regarding the presence of ARGs in subalpine lakes, the impact of anthropogenic pollution on their appearance and the potential role of various ecological interactions on their persistence in the system. 相似文献
156.
Ricardo Castilho Garcez Bianca Luise Teixeira Suelen dos Santos Schmitt Márcio Alvarez-Silva Andréa Gonçalves Trentin 《Cellular and molecular neurobiology》2009,29(8):1087-1091
Proliferation of neural crest (NC) stem cells and their subsequent differentiation into different neural cell types are key
early events in the development of the peripheral nervous system. Soluble growth factors present at the sites where NC cells
migrate are critical to the development of NC derivatives in each part of the body. In the present study, we further investigate
the effect of microenvironmental factors on quail trunk NC development. We show for the first time that EGF induces differentiation
of NC to the neuronal and melanocytic phenotypes, while fibroblast growth factor 2 (FGF2) promotes NC differentiation to Schwann
cells. In the presence of both EGF and FGF2, the neuronal differentiation predominates. Our results suggest that FGF2 stimulates
gliogenesis, while EGF promotes melanogenesis and neurogenesis. The combination of both growth factors stimulates neurogenesis.
These findings suggest that these two growth factors may play an important role in the fate decision of NC progenitors and
in the development of the peripheral nervous system. 相似文献
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Severino Adriano de Oliveira Lima Raniere Garcez Costa Sousa 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):842-844
Length–weight relationships (LWR) were estimated for six fish species from the Cujubim lake on the Madeira River. The specimens were sampled between in the months of March and November, 2019 and February, 2020 using gillnets (10 × 5 m, mesh size 40, 60, 80 and 100 mm) which were checked every 6 hr during a 24-hr period and casting nets (1.25 × 2.7 m, mesh size 40 mm) performed three times in this interval. This study reports new maximum lengths for four species and a new tentative LWR for one species. 相似文献