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1.
J Chem Ecol ; 42(8): 768-771, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27481346

RESUMEN

Phenolic compounds play a role in plant defense against herbivores. For some herbivorous insects, particularly root herbivores, host plants with high phenolic concentrations promote insect performance and tissue consumption. This positive relationship between some insects and phenolics, however, could reflect a negative correlation with other plant defenses acting against insects. Silicon is an important element for plant growth and defense, particularly in grasses, as many grass species take up large amounts of silicon. Negative impact of a high silicon diet on insect herbivore performance has been reported aboveground, but is unreported for belowground herbivores. It has been hypothesized that some silicon accumulating plants exhibit a trade-off between carbon-based defense compounds, such as phenolics, and silicon-based defenses. Here, we investigated the impact of silicon concentrations and total phenolic concentrations in sugarcane roots on the performance of the root-feeding greyback canegrub (Dermolepida albohirtum). Canegrub performance was positively correlated with root phenolics, but negatively correlated with root silicon. We found a negative relationship in the roots between total phenolics and silicon concentrations. This suggests the positive impact of phenolic compounds on some insects may be the effect of lower concentrations of silicon compounds in plant tissue. This is the first demonstration of plant silicon negatively affecting a belowground herbivore.


Asunto(s)
Escarabajos/efectos de los fármacos , Herbivoria/efectos de los fármacos , Fenoles/metabolismo , Raíces de Plantas/metabolismo , Saccharum/metabolismo , Silicio/metabolismo , Animales , Femenino , Masculino , Fenoles/farmacología , Saccharum/fisiología , Silicio/farmacología
2.
Mol Phylogenet Evol ; 63(3): 904-14, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22450357

RESUMEN

The Cotesia flavipes complex of parasitoid wasps (Hymenoptera: Braconidae) are economically important for the biological control of lepidopteran stemboring pests associated with gramineous crops. Some members of the complex successfully parasitize numerous stemborer pest species, however certain geographic populations have demonstrated variation in the range of hosts that they parasitize. In addition, the morphology of the complex is highly conserved and considerable confusion surrounds the identity of species and host-associated biotypes. We generated nucleotide sequence data for two mtDNA genes (COI, 16S) and three anonymous nuclear loci (CfBN, CfCN, CfEN) for the C. flavipes complex. To analyze genetic variation and relationships among populations we used (1) concatenated mtDNA and nDNA data, (2) a nDNA multilocus network approach, and (3) two species tree inference methods, i.e. Bayesian estimation of species trees (BEST) and Bayesian inference of species trees from multilocus data with (*)BEAST. All phylogenetic analyses provide strong support for monophyly of the complex and the presence of at least four species, C. chilonis (from China and Japan), C. sesamiae (from Africa), C. flavipes (originating from the Indo-Asia region but introduced into Africa and the New World), and C. nonagriae (from Australia and Papua New Guinea). Haplotype diversity of geographic populations relates to historical biogeographic barriers and biological control introductions, and reflects previous reports of ecological variation in these species. Strong discordance was found between the mitochondrial and nuclear markers in the Papua New Guinea haplotypes, which may be an outcome of hybridization and introgression of C. flavipes and C. nonagriae. The position of Cotesia flavipes from Japan was not well supported in any analysis and was the sister taxon to C. nonagriae (mtDNA, (*)BEAST), C. flavipes (nDNA) or C. flavipes+C. nonagriae (BEST) and, may represent a cryptic species. The concatenated five gene phylogenetic analyses did not support the overall separation and monophyly of clades associated with different host species, although some clades did show specific host associations, possibly due to localized host availability, rather than host specificity. Our results provide a framework for assessing whether distinct lineages represent cryptic species, and for examining parasitoid-host evolution and compatibility more generally. Given the limitations of morphological based identification for members of this complex, molecular identification is recommended prior to any biological control introductions.


Asunto(s)
Agentes de Control Biológico , Variación Genética , Lepidópteros , Filogenia , Avispas/genética , Animales , Teorema de Bayes , Complejo IV de Transporte de Electrones/genética , Genes Mitocondriales , Proteínas de Insectos/genética , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Proteína Relacionada con la Hormona Paratiroidea , Fragmentos de Péptidos , ARN Ribosómico 16S/genética
3.
Virus Res ; 141(2): 247-57, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19428738

RESUMEN

The island sugarcane planthopper, Eumetopina flavipes Muir, is the only known vector for Ramu stunt disease of sugarcane. This study examined the relationship between host plant distribution and abundance, and E. flavipes distribution, abundance and levels of population connectivity in Papua New Guinea (PNG), the Torres Strait (TS) and northern peninsula area (NPA) of Australia, as a first step in establishing E. flavipes invasion potential through the TS/NPA. Results show that E. flavipes utilises a wide range of Saccharum host species in PNG and that the occupation rates and abundances differed significantly among host types. For hosts in common, the proportion of plants occupied in PNG was significantly greater than in TS/NPA. This is likely the result of greater overall host density and connectivity in PNG. E. flavipes abundance per plant did not differ significantly between the two regions suggesting a possible plant-specific abundance and/or dispersal threshold independent of location. Whilst E. flavipes presence and persistence was highly variable at some TS/NPA locations, large and stable infestations occurred down the western edge of the TS archipelago. These populations appear to link PNG to the NPA and offer a potential incursion route for Ramu stunt disease. The stability of these populations appears to be associated with the availability and persistence of host material, which in turn is significantly affected by variation in cultivation practices. In the TS/NPA, implementation of pre-emptive management of E. flavipes via cultivation techniques, such as simultaneous tip-pruning, may be an effective means of control for the pest, and would be simpler and preferable to the direct management of Ramu stunt disease should it be detected in the TS/NPA.


Asunto(s)
Hemípteros/fisiología , Enfermedades de las Plantas/virología , Saccharum/virología , Animales , Australia , Papúa Nueva Guinea , Densidad de Población , Dinámica Poblacional
4.
Kans J Med ; 12(4): 132-135, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31803355

RESUMEN

INTRODUCTION: We evaluated the knowledge of non-steroidal anti-inflammatory drugs (NSAIDs) including their dosage, side effects, contraindications, and drug interactions among the patients in an outpatient rheumatology clinic. METHODS: Patients in a rheumatology clinic completed a short survey assessing their knowledge of over-the-counter NSAIDs. RESULTS: The survey was provided to 400 participants and 275 (68.5%) were using over-the-counter (OTC) NSAIDs. The majority of the participants identified their commonly used NSAID. Almost a third were unaware of the contraindication of NSAIDs such as peptic ulcer disease, chronic kidney disease, and hypertension. Nearly 53.9% participants denied having any discussion of OTC medications with their providers. Two-thirds of the respondents reported seeing only the medication packaging for the dose determination (67.8%). CONCLUSIONS: The gap in patient knowledge of the potential side effects and the lack of discussion of OTC medications by the providers may be predisposing the patients to preventable side effects from NSAIDs.

5.
Sci Rep ; 9(1): 7039, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-31065024

RESUMEN

Lepidopteran stemborers are among the most damaging agricultural pests worldwide, able to reduce crop yields by up to 40%. Sugarcane is the world's most prolific crop, and several stemborer species from the families Noctuidae, Tortricidae, Crambidae and Pyralidae attack sugarcane. Australia is currently free of the most damaging stemborers, but biosecurity efforts are hampered by the difficulty in morphologically distinguishing stemborer species. Here we assess the utility of DNA barcoding in identifying stemborer pest species. We review the current state of the COI barcode sequence library for sugarcane stemborers, assembling a dataset of 1297 sequences from 64 species. Sequences were from specimens collected and identified in this study, downloaded from BOLD or requested from other authors. We performed species delimitation analyses to assess species diversity and the effectiveness of barcoding in this group. Seven species exhibited <0.03 K2P interspecific diversity, indicating that diagnostic barcoding will work well in most of the studied taxa. We identified 24 instances of identification errors in the online database, which has hampered unambiguous stemborer identification using barcodes. Instances of very high within-species diversity indicate that nuclear markers (e.g. 18S, 28S) and additional morphological data (genitalia dissection of all lineages) are needed to confirm species boundaries.


Asunto(s)
Código de Barras del ADN Taxonómico , Lepidópteros/genética , Control de Plagas , Animales , Bases de Datos Genéticas , Lepidópteros/clasificación , Mariposas Nocturnas/genética , Filogenia , Cuarentena , Saccharum
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