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121.
Alan Rodrigues Teixeira Machado Viviane Aparecida Costa Campos Willian José Rodrigues da Silva Vicente Paulo Campos Ana Carolina de Mattos Zeri Denilson Ferreira Oliveira 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(2):431-441
To understand the effect of nematode Meloidogyne exigua infestation on coffee plants, resistant and susceptible coffee seedlings were inoculated with second-stage juveniles of M. exigua, and root metabolites were studied for four time intervals at 0, 24, 48 and 96 h. During this important period for parasite establishment, the concentrations of phenols, carbohydrates, amino acids and alkaloids in the roots were measured, and hydrogen nuclear magnetic resonance spectra of the root extracts were used to identify and quantify other metabolites. One of the most striking changes was the concentration of fumaric acid on resistant plants, which varied from 59 μg g(of root)?1 to 138 μg g(of root)?1 during the first 24 h of the nematode inoculation. The same level of variation was observed much later (96 h) in susceptible plants. Similarly, formic and quinic acid concentrations increased more rapidly in the resistant plants compared to the susceptibles. Sucrose concentrations increased to 370 % in the first 48 h in the resistant plants but showed no significant variation in the susceptible plant. Besides, the concentration of alkaloids was much higher at 24 and 48 h in the susceptibles compared to the resistant plants. These results suggest that the higher production of sucrose as well as formic, fumaric and quinic acids, and the lower production of alkaloids by the resistant cultivar in the first 48 h after the nematode inoculation are associated with the resistance of coffee plants to M. exigua. 相似文献
122.
Simões C De Mattos JC Sabino KC Caldeira-de-Araújo A Coelho MG Albarello N Figueiredo SF 《Fitoterapia》2006,77(2):94-99
Methanolic extracts obtained from different organs of Cleome rosea, collected from its natural habitat and from in vitro-propagated plants, were submitted to in vitro biological assays. Inhibition of nitric oxide (NO) production by J774 macrophages and antioxidant effects by protecting the plasmid DNA from the SnCl(2)-induced damage were evaluated. Extracts from the stem of both origins and leaf of natural plants inhibited NO production. The plasmid DNA strand breaks induced by SnCl(2) were reduced by extracts from either leaf or stem of both sources. On the other hand, root extracts did not show any kind of effects on plasmid DNA, and presented significant toxic effects to J774 cells. The results showed that C. rosea presents medicinal potential and that the acclimatization process reduces the plant toxicity both to plasmid DNA and to J774 cells, suggesting the use of biotechnology tools to obtain elite plants as source of botanical material for pharmacological and phytochemical studies. 相似文献
123.
Temperature sensitivity of soil organic matter decomposition varies with biochar application and soil type 总被引:1,自引:0,他引:1
Tatiana F. RITTL Luiza CANISARES Edvaldo SAGRILO Klaus BUTTERBACH-BAHL Michael DANNENMANN Carlos E. P. CERRI 《土壤圈》2020,30(3):336-342
Biochar application has the potential to improve soil fertility and increase soil carbon stock, especially in tropical regions. Information on the temperature sensitivity of carbon dioxide(CO_2) evolution from biochar-amended soils at very high temperatures, as observed for tropical surface soils, is limited but urgently needed for the development of region-specific biochar management targeted to optimize biochar effects on soil functions. Here, we investigated the temperature sensitivity of soil respiration to the addition of different rates of Miscanthus biochar(0, 6.25, 12.5, and 25 Mg ha~(-1)) in two types of soils with contrasting textures. Biochar-amended soil treatments and their controls were incubated at constant temperatures of 20, 30, and 40℃. Overall, our results show that: i) considering data from all treatments and temperatures, the addition of biochar decreased soil CO_2 emissions when compared to untreated soils;ii) CO_2 emissions from biochar-amended soils had a higher temperature sensitivity than those from biochar-free soils; iii) the temperature sensitivity of soil respiration in sandy soils was higher than that in clay soils; and iv) for clay soils, relative increases in soil CO_2 emissions from biochar-amended soils were higher when the temperature increased from 30 to 40℃, while for sandy soils, the highest temperature responses of soil respiration were observed when increasing the temperature from 20 to 30℃. Together, these findings suggest a significantly reduced potential to increase soil organic carbon stocks when Miscanthus biochar is applied to tropical soils at high surface temperatures, which could be counteracted by the soil-and weather-specific timing of biochar application. 相似文献
124.
Karina Batista Luciana Gerdes Alessandra Aparecida Giacomini Waldssimiler Teixeira de Mattos Ivani Pozar Otsuk 《African Journal of Range and Forage Science》2019,36(1):41-48
The response of legumes to the supply of either phosphorus (P) or calcium (Ca) alone has been extensively investigated but no prior studies have evaluated their combinations in the perennial legume Macrotyloma axillare (Macrotyloma legume). This study assessed the mineral composition of Macrotyloma legume in response to the combined application of P and Ca in an Ultisol. The experiment was conducted in a greenhouse in Nova Odessa city, São Paulo, Brazil. Five rates of P and Ca, respectively, were combined in a 52 incomplete fractional factorial design. Thus, the treatments consisted of 13 P and Ca combination rates (respectively, in mg dm?3): 0?0, 0?40, 0?80, 15?20, 15?60, 30?0, 30?40, 30?80, 45?20, 45?60, 60?0, 60?40 and 60?80 arranged in a randomised block design with four replications. Mineral composition was evaluated after two harvests (53 d after sowing and 34 d after the first harvest). During the initial growth of the Macrotyloma legume, P × Ca interactions occurred. The P supply antagonistically influenced the nitrogen content. The excess P supply reduced nitrogen accumulation in the shoots and caused a lack of nitrogen in the leaves. The Ca supply synergistically impacted the magnesium content and caused a ‘Viets effect’ in potassium content. 相似文献
125.
Sequential medium with GH and IGF‐1 improved in vitro development of bovine preantral follicles enclosed in ovarian tissue 下载免费PDF全文
Carolina Rodriguez Jimenez Jovana Luiza de Azevedo Torres Ciro Alexandre Alves Jurandy Mauro Penitente‐Filho Wagner Gonzaga Gonçalves 《Reproduction in domestic animals》2018,53(5):1103-1113
The growth hormone (GH) and growth insulin‐like factor‐1 (IGF‐1) act directly upon the regulation and growth in the different phases of preantral follicles. Thus, it is necessary to define their sequentiality until the in vitro preovulatory development. Therefore, the study aimed to assess the effects of a sequential medium containing GH and/or IGF‐1 in the long‐duration in vitro culture of preantral ovarian follicles. Ovarian fragments were cultivated: first half (days 1–7), second half (days 7–14) or during 14 culture days. Treatments were identified as: αMEM+; GH → IGF‐1; IGF‐1 → GH and GH + IGF‐1. The culture was designed in 24‐well plates, in an incubator at 37°C and 5% CO2. The parameters of normality, viability, follicles (primordial/in developing) and follicle diameter were evaluated. In addition, the ultrastructure was confirmed with electron transmission microscopy. The results showed that the culture treated with GH → IGF‐1 kept the follicular normality and the viability until the 14th day of culture and increased both in the follicular development until 7th day and in the follicular diameter until 14th day, when compared to the control. The treatments IGF‐1 → GH and GH + IGF‐1 were not effective in the developing and follicular diameter after 7 days of culture, and also reduced the percentage of viability. It is concluded that the bovine preantral follicles cultured in the sequential medium treated with GH → IGF‐1 improved the follicular development until the first half of the culture and kept these parameters with normality, viability and ultrastructure until the second half of the in vitro culture. 相似文献
126.
Nutritional evaluation of the legume Macrotyloma axillare using in vitro and in vivo bioassays in sheep 下载免费PDF全文
P. M. T. Lima G. D. Moreira G. Z. Sakita A. S. Natel W. T. Mattos F. M. A. Gimenes L. Gerdes C. McManus A. L. Abdalla H. Louvandini 《Journal of animal physiology and animal nutrition》2018,102(2):e669-e676
This study consisted of two experiments with the following objectives: to evaluate the effects of tannins from the tropical legume macrotiloma (Macrotyloma axillare) on total gas and methane (CH4) production, as well as on ruminal fermentation parameters by performing an in vitro bioassay, with samples incubated with and without polyethylene glycol (PEG) in a semi‐automatic system; and secondly in a 17 day in vivo experiment, to determine apparent total tract digestibility (ATTD) of dietary nutrients and ruminal fermentation parameters of 12 intact 8‐ to 9‐month‐old Santa Inês (averaging 24.95 ± 1.8 kg body weight) ewes fed tropical grass hay supplemented with macrotiloma hay. The ewes were divided into two treatment groups depending on their diet: chopped aruana grass hay (Panicum maximum cv. Aruana) (control—CON); and aruana grass hay supplemented with chopped macrotiloma hay (macrotiloma—MAC). The animals were kept for 5 consecutive days in metabolic cages for the ATTD assay, and at the end of this period, samples of rumen fluid were collected from each ewe to determine ammoniacal nitrogen (NH3‐N) and short‐chain fatty acid (SCFA) production, and protozoa count. For the in vitro assay, a decrease in total gas and CH4 production was observed for samples incubated without PEG (p < .05). No differences were observed for the other parameters evaluated (p > .05). In the in vivo experiment, increased intake and ATTD of crude protein were observed for the animals fed MAC when compared to CON (p < .05). For rumen fermentation parameters, increased NH3‐N, total SCFA and isobutyrate concentrations, as well as reduced protozoa count were observed for MAC when compared to CON (p < .05). The results observed here indicated the potential of macrotiloma for use as a ruminant feed, and antimethanogenic potential of this plant was noted. 相似文献
127.
Jurandy Mauro Penitente‐Filho Carolina Rodrigues Jimenez Adriana Moreira Zolini Erly Carrascal Jovana Luiza Azevedo Camila Oliveira Silveira Fabrício Albani Oliveira Ciro Alexandre Alves Torres 《Animal Science Journal》2015,86(2):148-152
In order to evaluate whether ovarian volume, presence and diameter of the corpus luteum (CL) have effects on the number and quality of bovine recovered oocytes, 110 ovaries were obtained from the slaughterhouse. Cumulus oocytes complex were aspirated and evaluated under stereomicroscope. Oocytes were counted and classified according to their quality (Grades I, II, III and IV). Ovarian volume was weakly correlated to the number of good quality oocytes (P < 0.05). Ovaries with CL showed greater numbers of good quality oocytes than ovaries without CL (P < 0.05). Further, presence of CL and its diameter positively influenced the probability of recovering good quality oocytes (P < 0.05). In conclusion, ovarian volume is not a good parameter itself to predict important ovarian characteristics; moreover, analysis of CL, its presence and diameter, may be a good tool to improve efficiency on in vitro embryo production programs. 相似文献
128.
Mattos Bruno D. de Cademartori Pedro H. G. Missio André L. Gatto Darci A. Magalhães Washington L. E. 《Wood Science and Technology》2015,49(6):1281-1294
Wood Science and Technology - The aim of this study was to evaluate treatability, morphology and mechanical resistance of composites prepared by in situ polymerization of methyl methacrylate on... 相似文献
129.
130.
George N.Zaimes Petros A.Tsioras Chrysovalantis Kiosses Mustafa Tufekcioglu Sergiy Zibtsev Ilya Trombitsky Razvan Uratu Luiza Gevorgyan 《林业研究》2020,31(1):257-268
Protected areas are necessary for the conservation and enhancement of biodiversity.Wildfires are major threats to forests and other natural areas,because they may cause irreversible damages.The aim of this study was to analyze the perspective of experts(N=284),from six countries of the Black Sea,on the current status and problems of protected areas and wildfires.Understanding their points of view could enhance future management on these issues in the region.Data collection was carried out for 9 months,using a web-based questionnaire.Wildfires were perceived as a serious problem in Turkey,Armenia and Greece but as a substantially less serious problem in Romania,Ukraine and Moldova.In Greece,Armenia,and especially Ukraine,the current designated protected areas are considered sufficient to maintain biodiversity,while in Romania,Turkey,and especially Moldova,more areas should be designated as protected.A major need in all countries(except for Turkey)is the increased use of information and communication technologies for both wildfire suppression and protected area management.Experts were divided on whether wildfire suppression and management of protected areas are interconnected.However,there is growing awareness of the adverse impacts of climate change in protected areas and the frequency of wildfires in the future.The most frequently suggested measures to alleviate these impacts were:changes in forest management and increasing public awareness for wildfire suppression,along with changes in forest management and increased staff training to enhance protected area conservation. 相似文献