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51.
Sandrelli F Tauber E Pegoraro M Mazzotta G Cisotto P Landskron J Stanewsky R Piccin A Rosato E Zordan M Costa R Kyriacou CP 《Science (New York, N.Y.)》2007,316(5833):1898-1900
Diapause is a protective response to unfavorable environments that results in a suspension of insect development and is most often associated with the onset of winter. The ls-tim mutation in the Drosophila melanogaster clock gene timeless has spread in Europe over the past 10,000 years, possibly because it enhances diapause. We show that the mutant allele attenuates the photosensitivity of the circadian clock and causes decreased dimerization of the mutant TIMELESS protein isoform to CRYPTOCHROME, the circadian photoreceptor. This interaction results in a more stable TIMELESS product. These findings reveal a molecular link between diapause and circadian photoreception. 相似文献
52.
Adriano Francis Dorigan Silvino Intra Moreira Sarah da Silva Costa Guimarães Valter Cruz-Magalhães Eduardo Alves 《Pest management science》2023,79(12):4731-4753
Fungicides are indispensable for high-quality crops, but the rapid emergence and evolution of fungicide resistance have become the most important issues in modern agriculture. Hence, the sustainability and profitability of agricultural production have been challenged due to the limited number of fungicide chemical classes. Resistance to site-specific fungicides has principally been linked to target and non-target site mechanisms. These mechanisms change the structure or expression level, affecting fungicide efficacy and resulting in different and varying resistance levels. This review provides background information about fungicide resistance mechanisms and their implications for developing anti-resistance strategies in plant pathogens. Here, our purpose was to review changes at the target and non-target sites of quinone outside inhibitor (QoI) fungicides, methyl-benzimidazole carbamate (MBC) fungicides, demethylation inhibitor (DMI) fungicides, and succinate dehydrogenase inhibitor (SDHI) fungicides and to evaluate if they may also be associated with a fitness cost on crop pathogen populations. The current knowledge suggests that understanding fungicide resistance mechanisms can facilitate resistance monitoring and assist in developing anti-resistance strategies and new fungicide molecules to help solve this issue. © 2023 Society of Chemical Industry. 相似文献
53.
da Silva Isadora Gonçalves Castoldi Renata de Oliveira Charlo Hamilton César de Souza Miranda Mateus Nunes Thaíssa Dias Cardoso Costa Luciene Lacerda Lemes Ernane Miranda 《Journal of Crop Science and Biotechnology》2020,23(2):191-196
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of... 相似文献
54.
Samanta A Costa MH Nunes EL Vieira SA Xu L Myneni RB 《Science (New York, N.Y.)》2011,333(6046):1093; author reply 1093
Zhao and Running (Reports, 20 August 2010, p. 940) reported a reduction in global terrestrial net primary production (NPP) from 2000 through 2009. We argue that the small trends, regional patterns, and interannual variations that they describe are artifacts of their NPP model. Satellite observations of vegetation activity show no statistically significant changes in more than 85% of the vegetated lands south of 70°N during the same 2000 to 2009 period. 相似文献
55.
T Guimarães C Miranda M Pinto E Silva L Damásio AL Costa MJ Correia JC Duarte C Cosinha G Lopes G Thompson A Rocha 《Reproduction in domestic animals》2014,49(6):926-933
A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli. 相似文献
56.
ent-Pimara-8(14),15-dien-19-oic acid (PA) isolated from Viguiera arenaria (Asteraceae; Heliantheae) inhibited rat carotid rings contraction induced by phenylephrine (10(-8) mol/l) or potassium chloride (45 mmol/l) at concentration ranging from 5 to 20 microg/ml. This inhibitory effect was not reversible after the removal of this compound from the medium bath. 相似文献
57.
58.
ent-kaurenoic acid (KA) isolated from Viguiera robusta was tested for activity on vascular smooth muscle contactility. Cumulative concentration-response curves were obtained for a stepwise increase (10(-10)-10(-05) mol/l) in the concentration of phenylephrine (Phe), a selective alpha(1)-adrenergic agonist. The effects in the presence of KA (0.2, 2.0 and 20.0 microg/ml), and 90 min after the removal of KA from the medium bath were compared to controls. At 20.0 microg/ml, KA inhibited the in vitro contractility of rat carotid artery elicited by Phe, but had no effect at lower concentrations (0.2 and 2.0 microg/ml). The effect elicited by KA was reversible after 90 minutes. 相似文献
59.
60.
da Costa Eline Nayara Dantas de Souza Jéssica Carneiro Pereira Marilane Andrade de Souza Marcelo F. Landim de Souza Weber F. Landim da Silva Daniela Mariano Lopes 《Agroforestry Systems》2021,95(8):1647-1659
Agroforestry Systems - Inland waters such as streams that receive carbon from terrestrial landscapes usually have a net heterotrophic metabolism and emit significant amounts of CO2 to the... 相似文献