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排序方式: 共有1225条查询结果,搜索用时 31 毫秒
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2.
Carmen García-Limones Ana Hervs Juan A. Navas-Corts Rafael M. Jimnez-Díaz Manuel Tena 《Physiological and Molecular Plant Pathology》2002,61(6):325
To ascertain if active oxygen species play a role in fusarium wilt of chickpea caused by Fusarium oxysporum f. sp. ciceris, the degree of lipid peroxidation (malondialdehyde formation) and the activity levels of diamine oxidase (DAO), an apoplastic H2O2-forming oxidase, and several antioxidant enzymes, namely ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), guaiacol-dependent peroxidase (GPX) and superoxide dismutase (SOD), were determined spectrophotometrically in roots and stems of ‘WR315’ (resistant) and ‘JG62’ (susceptible) chickpea cultivars inoculated with the highly virulent race 5 of the pathogen. Moreover, APX, CAT, GPX and SOD were also analysed in roots and stems by gel electrophoresis and activity staining; and the protein levels of APX and SOD in roots were determined by Western blotting. In roots, infection by the pathogen increased lipid peroxidation and CAT and SOD activities, although such responses occurred earlier in the incompatible compared with the compatible interactions. APX, GPX and GR activities were also increased in infected roots, but only in the compatible interaction. In stems, infection by the pathogen increased lipid peroxidation and APX, CAT, SOD and GPX activities only in the compatible interaction, and DAO activity only in the incompatible one. In general, electrophoregrams agreed with the activity levels determined spectrophotometrically and did not reveal any differences in isoenzyme patterns between cultivars or between infected and non-infected plants. Further, Western blots revealed an increase in the root protein levels of APX in the compatible interaction and in those of SOD in both compatible and incompatible interactions. In conclusion, whereas enhanced DAO activity in stems, and earlier increases in lipid peroxidation and CAT and SOD activities in roots, can be associated with resistance to fusarium wilt in chickpea, the induction of the latter three parameters in roots and stems along with that of APX, GR (only in roots) and GPX (only in stems) activities are rather more associated with the establishment of the compatible interaction. 相似文献
3.
F.J. López-Escudero C. del Río J.M. Caballero M.A. Blanco-López 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(1):79-85
Resistance of 23 important olive cultivars to Verticillium dahliae has been evaluated in four experiments under controlled conditions. Nine-month-old nursery olive plants were inoculated with a cotton non-defoliating (ND) (V4) or a cotton defoliating (D) (V117) isolate of V. dahliae. Resistance was evaluated by assessing symptom severity using a 0–4 rating scale and estimating the area under disease progress curves. The percentage of plants killed and of those which recovered from the disease were used as additional parameters for including a particular cultivar into a defined category. Most of the evaluated cultivars were susceptible, although at different levels, to both isolates of V. dahliae. All cultivars were more susceptible to the D pathotype than to the ND one. A group of 11 cultivars, including several important Spanish cultivars, were susceptible or extremely susceptible to both pathotypes of V. dahliae. A second group showed differences of resistance depending on the pathotype used. They were susceptible or extremely susceptible to the D pathotype but resistant or moderately susceptible to the ND one. Finally, 'Frantoio', 'Oblonga' and 'Empeltre' were moderately susceptible to the D isolate of V. dahliae and resistant to the ND one. The resistance of 'Empeltre' was evident by the plant ability to recover from infection with either isolates. 'Empeltre' is considered to be a valuable cultivar for inclusion in breeding programmes for resistance to Verticillium wilt. 相似文献
4.
Efficacy of a mephentermine‐based product as a vasopressor and a cardiac performance enhancer when given intramuscularly to cattle
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D. N. Q. Cunha C. L. del Rio B. L. Youngblood E. L. Ferris G. E. Geist Y. Ueyama L. C. Franz S. Mathur R. L. Hamlin 《Journal of veterinary pharmacology and therapeutics》2018,41(2):274-280
The goal of this study was to confirm the vasopressor and cardiac effects of POTENAY® INJETÁVEL (POT), a mephentermine‐based product, given to cattle with induced vascular/cardiac depression. Ten healthy Holstein cattle (206 ± 13 kg) followed a randomized‐complete‐block design (RCBD) utilizing crossover study design. Each animal randomly received (1 ml/25 kg, IM) of either POT (n = 10) or volume‐matched placebo control (0.9%NaCl, CP, n = 10). A subset of animals (n = 5) received POT first (day 0) while the remaining (n = 5) received CP; after a six‐day washout period, cattle received the opposite compound. Animals were anesthetized and catheterized for systemic/left ventricular hemodynamic monitoring. Myocardial dysfunction/hypotension was induced by increasing the end‐tidal isoflurane concentration until arterial blood pressure was 20% lower than at baseline and remained stable. Once the animal was determined to be hypotensive and hemodynamically stable, steady‐state hypotensive baseline data (BL2) were acquired, and treatment with either POT or CP was given. Data were acquired post‐treatment at every 15 min for 90 min. POT improved cardiac output (+68 L/min, ±14%, p < 0.05), MAP (+14 mmHg, ±4%, p < 0.05), HR (+22 bpm, ±8%, p < 0.05), and peak rates of ventricular pressure change during both systole (dP/dtmax: +37 mmHg/s ±13%, p < 0.05) and diastole (dP/dtmin: +31 mmHg/s, ±7%, p < 0.05). No improvements were noted following placebo‐control administration. Results indicate that POT improves cardiac performance and systemic hemodynamics in cattle with induced cardiovascular depression when given as single intramuscular injection. 相似文献
5.
6.
Nicols Javier Litterio Augusto Matías Lorenzutti María del Pilar Zarazaga Martín Alejandro Himelfarb Manuel Ignacio San Andrs‐Larrea Juan Manuel Serrano‐Rodríguez 《Journal of veterinary pharmacology and therapeutics》2021,44(1):68-78
Cefquinome is a fourth‐generation cephalosporin that is used empirically in goats. Different physiologic factors like pregnancy or lactation could determine the pharmacokinetic behavior of drugs in the organism. The objectives of this study are to (a) compare the pharmacokinetics of cefquinome after intravenous and intramuscular administration in adult nonpregnant (n = 6), pregnant (n = 6), and lactating goats (n = 6), at a dose of 2 mg/kg, with rich sampling by nonlinear mixed‐effects modeling, (b) conduct a pharmacokinetic/pharmacodynamic analysis to evaluate the efficacy of the recommended posology in goats with different physiological states, and (c) determine the optimal posology that achieve a PTA value ≥ 90%, taking into account a T > MIC ≥ 60% of a MIC value ≤ 0.25 µg/ml, in the different subpopulations of goats for both routes. Gestation significantly increased Ka and V1, while reduced F0, Cl, and Q. On the other hand, lactation significantly increased V1 and reduced Tk0. Cefquinome concentrations achieved in placental cotyledon, amniotic fluid, and fetal serum indicate a minimal penetration across the placental barrier. Moreover, milk penetration of cefquinome was minimal. The total body clearance of cefquinome for goats was 0.29 L kg?1 hr?1, that is apparently higher than the reported for cows (0.13 L kg?1 hr?1) and pigs (0.16 L kg?1 hr?1). So, the optimal dose regimen for cefquinome after intravenous and intramuscular administration required higher dose and frequency of administration compared with recommendations for cows or pigs. Therefore, 2 mg kg?1 8 hr?1 and 5 mg kg?1 12 hr?1 could be used for IV and IM routes, respectively, for the treatment of respiratory infections caused by P. multocida and M. haemolytica, but only 5 mg kg?1 12 hr?1 by both routes should be recommended for Escherichia coli infections. 相似文献
7.
Carmen Klein Melanie Feist Gabriela Knubben-Schweizer Britta Dobenecker 《Journal of animal physiology and animal nutrition》2021,105(6):997-1001
High-yielding dairy cows collapsed and died displaying signs of a disturbed central nervous system (muscle tremor, convulsion) and a considerably reduced body condition score. An intense diagnostic screening did not allow to confirm a definite diagnosis. Therefore, further analyses including an evaluation of feeds and feeding were initiated. The herd was fed a total mixed ration (TMR) based on corn and grass silage of moderate nutritive value supplemented with various amounts of chocolate chips. In retrospect, the amount of chocolate chips added to the respective TMR batches could not be quantified. These chips were purchased from a company producing bakery and chocolate products for human consumption and added to the silage and therefore to the TMR in order to increase the energy intake of the animals. Because the TMR, which was fed during the time of the incidence, was no longer available, a sample of a later batch of silage was examined. The amount of chocolate chips was quantified (0.44% per fresh matter), and a theobromine analysis was performed in the chocolate chips of the available batch (69.7 mg/100 g fresh matter). Because of the possible link between chocolate intake and observed signs, an immediate cessation of using the chocolate chips was recommended in addition to an optimisation of the TMR, that is an increase of the energy density. Even though the theobromine intake during the time of the incidence is unknown and information about toxicity of theobromine in ruminants is limited, we suspect that the feeding of chocolate in this case caused all signs including the sudden death of the cows. Further reasons are that no differential diagnoses were established and the problems at the farm stopped after removing the chocolate from the TMR. 相似文献
8.
The use of midday leaf water potential for scheduling deficit irrigation in vineyards 总被引:1,自引:0,他引:1
J. Girona M. Mata J. del Campo A. Arbonés E. Bartra J. Marsal 《Irrigation Science》2006,24(2):115-127
Midday leaf water potential (Ψmd) was monitored for 3 years at a commercial vineyard (cv. Pinot Noir) under four irrigation strategies. Three treatments were
established based on irrigating vines with 4–6 mm/day, when daily measured Ψmd was more negative than the pre-defined threshold. After the first experimental year, thresholds were adjusted for each treatment
as: (1) Control (C), irrigated when Ψmd was less than −0.6 MPa at the beginning of the season and gradually fell to −0.8 MPa at about mid-June, after which the threshold
was maintained at −0.8 MPa until harvest. (2) Control–Deficit (CD), irrigated as C from bud-break to mid-June (around the
middle of Stage II of fruit growth), and from then until harvest when Ψmd decreased below −1.2 MPa. (3) Deficit–Deficit (DD), irrigated when Ψmd was less than −1.0 from bud break to mid-May (about the middle of fruit growth Stage I), and after that time the Ψmd threshold became −1.2 MPa until harvest. A fourth treatment was applied following a soil water budget approach (WB). All
treatments were replicated five times but irrigation in the Ψmd-based treatments were independently applied to each of the replicate plots, whereas irrigation for WB was applied equally
to all replications. The more site-specific information obtained from Ψmd thresholds in C provided substantial advantages for yield homogeneity and repeatability of results with respect to WB, thus
demonstrating the method’s greater ability to account for spatial variability. Average applied water for the 3 years in C,
CD, and DD was 374, 250, and 178 mm, respectively, while the yields were 11.8, 9.2, and 6.1 kg/vine, respectively. The CD
treatment produced better juice quality than C, and was superior in other quality parameters to both C and DD. However, over
the study period, an important carryover effect was observed in the yields and the grape size of CD, which tended to diminish
from year to year relative to C. 相似文献
9.
Among the most important Mediterranean annual crops durum wheat is widely grown in drought-prone areas. Therefore improving water-use efficiency 《分子植物育种》2007,5(2):223-223
Among the most important Mediterranean annual crops, durum wheat is widely grown in drought-prone areas. Therefore, improving water-use efficiency (WUE) of durum wheat represents a major breeding goal. IDu-WUE (Improving Durum wheat for Water Use Efficiency and yield stability through physiological and molecular approaches) is a collaborative project among public and private research centres in Italy, Spain and WANA (West Asia and North Africa) countries (Morocco, Tunisia, Syria and Lebanon) funded by the European Union aimed at investigating the genetic variation for WUE and yield stability in durum wheat grown in Mediterranean droughtprone areas. During the first year of the project, a number of morpho-physiological traits (e.g. early vigour, flowering time, leaf rolling, number of fertile tillers, etc.), WUE, WUE-related traits (e.g. carbon isotope discrimination, canopy temperature, chlorophyll fluorescence, etc.), yield and its components have been investigated in a RIL population (249 lines) and a collection of ca. 190 durum wheat accessions characterized by a high level of linkage disequilibrium (Maccaferri et al., 2005), 相似文献
10.
Isabel GARRIDO Carmen M. MARTNEZ Pilar FLORES Pilar HELLN Fulgencio CONTRERAS Jos FENOLL 《土壤圈》2024,34(3):641-651
Agriculture has a close relationship with nature, but it can also be the source of negative and permanent environmental effects. The use of pesticides in modern agriculture is a common practice, but their side effects on the environment cannot be disregarded. In this study, we evaluated a combination of solarization and ozonation techniques for the elimination of six amide pesticides (boscalid, chlorantraniliprole, cyflufenamid, fluopyram, napropamide, and propyzamide) in soil. Initial experiments were performed with four different soils to assess the efficiency of this methodology at different soil temperatures and ozone dosages under laboratory conditions, and then a greenhouse pot experiment was conducted under controlled conditions during summer. Fifty days after the onset of the experiments, higher degradation percentages of amide pesticides were observed in ozonized soils than in other treated soils, particularly when ozone was applied at 10 cm soil depth. The results show that the utilization of ozonation, along with solarization, represents a valid method for degrading residues of the studied pesticides and suggest that this combined technology may be a promising tool for remediating pesticide-polluted soils. 相似文献