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91.
BACKGROUND: The small number of available nematicides and restrictions on the use of non‐fumigant nematicides owing to high toxicity to human and non‐target organisms hinder effective nematode control. The nematicidal efficacy of MCW‐2, a new nematicide of the fluoroalkenyl group, was evaluated against the root‐knot nematode Meloidogyne javanica (Treub.) Chitwood. RESULTS: MCW‐2 showed irreversible nematicidal activity against second‐stage juveniles of M. javanica in vitro, following exposure for 48 h at concentrations as low as 0.5 mg L?1, in contrast to fenamiphos or cadusafos. When exposed to MCW‐2 for shorter periods, motile juveniles became immobile with time after rinsing in water. MCW‐2 at 8 mg L?1 inhibited nematode hatching, which, however, recovered after rinsing in water. In pot and plot experiments, 0.5 mg MCW‐2 L?1 soil and 2 kg MCW‐2 ha?1, respectively, controlled M. javanica similarly to or better than fenamiphos or cadusafos at the same concentrations or at their recommended doses. In the soil, the nematicidal activity of MCW‐2 was less persistent than that of fenamiphos. CONCLUSION: MCW‐2 has potential to be used as a new non‐fumigant nematicide that probably has a novel mode of action. Copyright © 2009 Society of Chemical Industry 相似文献
92.
93.
Nadia Majeed Bushra Javaid Farah Deeba Syed Muhammad Saqlan Naqvi David S. Douches 《American Journal of Potato Research》2018,95(4):383-394
Germin like proteins (GLPs) are a large group of related and ubiquitous plant proteins which are considered to be involved in different processes important for plant development and defense. Multiple functional copies of this gene family have been reported in a number of species (wheat, barley, rice, soybean mosses and liverwort), and their role is being evaluated by gene regulation studies and transgenic approaches. To analyze the role of a rice (Oryza sativa) root expressed germin like protein1 OsRGLP1, for its antifungal activity, transgenic potato plants were developed. These transgenic potato plants were molecularly characterized and biologically assessed after inoculation with Fusarium oxysporum f. sp. tuberosi. Functional analysis showed high accumulation of H2O2, increased Superoxide Dismutase (SOD) activity and no oxalate oxidase activity (OxO) in transgenics in comparison to nontransformed control. This increased SOD activity, resistance to heat and sensitivity to H2O2 suggest it is a Fe-like SOD. OsRGLP1 expression in potato plants exhibited enhanced resistance in comparison to nontransformed wild type plants suggesting its role in providing protection against Fusarium oxysporum f. sp. tuberosi through elevated SOD level. Overall, results suggest that OsRGLP1 is a candidate for the engineering of potato plants with increased fungal tolerance however, the greater height and tuber number was observed. This phenotype associated with the resistance needs to be evaluated to determine if this is a positive or negative feature. 相似文献
94.
Miguel Gozalo-Marcilla Stelio PL. Luna Nadia Crosignani José NP Puoli Filho Fábio S. Possebon Ludovic Pelligand Polly M. Taylor 《Veterinary anaesthesia and analgesia》2017,44(5):1116-1127
Objective
To evaluate intravenous (IV) detomidine with methadone in horses to identify a combination which provides sedation and antinociception without adverse effects.Study design
Randomized, placebo-controlled, blinded, crossover.Animals
A group of eight adult healthy horses aged (mean ± standard deviation) 7 ± 2 years and 372 ± 27 kg.Methods
A total of six treatments were administered IV: saline (SAL); detomidine (5 μg kg?1; DET); methadone (0.2 mg kg?1; MET) alone or combined with detomidine [2.5 (MLD), 5 (MMD) or 10 (MHD) μg kg?1]. Thermal, mechanical and electrical nociceptive thresholds were measured, and sedation, head height above ground (HHAG), cardiopulmonary variables and intestinal motility were evaluated at 5, 15, 30, 45, 60, 75, 90, 120 and 180 minutes. Normal data were analyzed by mixed-model analysis of variance and non-normal by Kruskal–Wallis (p < 0.05).Results
Nociceptive thresholds in horses administered methadone with the higher doses of detomidine (MMD, MHD) were increased above baseline to a greater degree and for longer duration (MMD: 15–30 minutes, MHD: 30–60 minutes) than in horses administered low dose with methadone or detomidine alone (MLD, DET: 5–15 minutes). No increases in nociceptive thresholds were recorded in SAL or MET. Compared with baseline, HHAG was lower for 30 minutes in MMD and DET, and for 45 minutes in MHD. No significant sedation was observed in SAL, MET or MLD. Intestinal motility was reduced for 75 minutes in MHD and for 30 minutes in all other treatments.Conclusions
Methadone (0.2 mg kg?1) potentiated the antinociception produced by detomidine (5 μg kg?1), with minimal sedative effects.Clinical relevance
Detomidine (5 μg kg?1) with methadone (0.2 mg kg?1) produced antinociception without the adverse effects of higher doses of detomidine. 相似文献95.
Filipa Cox Nadia Barsoum Martin I. Bidartondo Isabella Børja Erik Lilleskov Lars O. Nilsson Pasi Rautio Kath Tubby Lars Vesterdal 《Annals of Forest Science》2010,67(2):200-200
The functionally critical role of mycorrhizal fungi in forest ecosystems, and the imminent threat of climate change that may
act to alter mycorrhizal functional biodiversity, means there is an urgent need for a regional to continental-scale assessment
of mycorrhizal distributions. Until recently, it had not been possible to cost-effectively assess mycorrhizas precisely and
accurately. A large-scale survey of ICP Forests plots would be only the first stage in answering many of the questions outlined
above, but it is essential if future studies are going to address these questions with hypothesis-driven research in a cohesive
manner, rather than remain independent for lack of a unified approach. The chance to utilise the vast network of biomonitoring
plots at this time is a remarkable opportunity because it minimises the logistics and costs associated with achieving such
an enormous effort and provides a rare stable — past and future — ground for forest ecosystem scientific investigation. In
the face of rapid global change, we finally have an opportunity to accurately integrate mycorrhizal distribution data with
long-term environmental monitoring, providing a basic understanding of functionally crucial organisms, and at the same time
creating an invaluable resource for future research. 相似文献
96.
Hoffmann M Hilton-Taylor C Angulo A Böhm M Brooks TM Butchart SH Carpenter KE Chanson J Collen B Cox NA Darwall WR Dulvy NK Harrison LR Katariya V Pollock CM Quader S Richman NI Rodrigues AS Tognelli MF Vié JC Aguiar JM Allen DJ Allen GR Amori G Ananjeva NB Andreone F Andrew P Aquino Ortiz AL Baillie JE Baldi R Bell BD Biju SD Bird JP Black-Decima P Blanc JJ Bolaños F Bolivar-G W Burfield IJ Burton JA Capper DR Castro F Catullo G Cavanagh RD Channing A Chao NL Chenery AM Chiozza F Clausnitzer V 《Science (New York, N.Y.)》2010,330(6010):1503-1509
Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species. 相似文献
97.
Maria Rosa Simon Elena K. Khlestkina Nadia S. Castillo Andreas Börner 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(3):317-324
The foliar wheat disease septoria tritici blotch can cause significant yield losses. A source of resistance has been mapped
on chromosome 7D of spelt wheat, Triticum aestivum L. subsp. spelta (L.) Thell. The microsatellite-based genetic map was constructed from a set of 87 single-chromosome recombinant doubled-haploid
lines bred from the cross between the landrace ‘Chinese Spring’ and a ‘Chinese Spring’-based line carrying chromosome 7D from
spelt wheat. Two regions of the chromosome were associated with isolate-specific QTL expressed one at the seedling and another
at the adult plant stage. The seedling resistance locus QStb.ipk-7D1 was found in the centromeric region of chromosome 7D, which corresponds to the location of the major resistance genes Stb4 originating from bread wheat cultivar ‘Tadinia’ and Stb5 originating from Triticum tauschii. The adult resistance locus QStb.ipk-7D2 was found on the short arm of chromosome 7D in a similar position to the locus Lr34/Yr18 known to be effective against multiple pathogens. Composite interval mapping confirmed QStb.ipk-7D1 and QStb.ipk-7D2 to be two distinct loci. 相似文献
98.
Nadia Stegeman J. Jill Heatley Aline Rodrigues Roy Pool 《Journal of Exotic Pet Medicine》2010,19(4):298-303
A cachexic 2-year-old koi (Cyprinus carpio) presented with progressive distension of the coelom (1-month period) and anorexia of 2 days' duration. The fish had been maintaining a normal swimming position, although it was often observed low in the water column. Water quality was within normal limits. A skin scrape, fin clip, and gill clip were unremarkable. The respiration rate (opercular movement) was elevated at 100 breaths per minute. Blood chemistry values demonstrated a hypoalbuminemia (1.3 g/dL), elevated uric acid (1.3 mg/dL), elevated creatine kinase (>14,000 U/L), and hyperkalemia (3.9 mmol/L). Ultrasound revealed a fluid-filled coelom and a soft tissue mass containing large vessels filling most of the coelomic cavity. Fine-needle aspirates of the mass were nondiagnostic, though a poorly exfoliating mesenchymal tumor was suspected. The mass was surgically excised. Pathological examination of the mass revealed it to be a poorly demarcated and unencapsulated neoplasm forming 3 histological patterns in which a spindle cell stromal component predominated over an intermediate-sized blastema and much smaller tubular patterns. These features were most consistent with a nephroblastoma. The koi survived 5 days postoperatively but remained low in the water column and was found dead on day 6. A full necropsy of this patient was not performed. 相似文献
99.
Nitrogen fertilization management under water limited conditions needs to be refined to save environmental ecosystems and increase economic returns. Two-year field studies in a split-plot design were conducted to investigate the response of maize to different nitrogen rates (N100 = 100, N130 = 130, and N160 = 160?kg N ha?1) under two irrigation levels (100 or 75% of water requirements). Under deficit irrigation, water and N were used more efficiently than normal water supply. N-fertilization of drip irrigated maize grown under deficit irrigation with N160 increased the uptake of N, P and K by 35, 29 and 70% compared with N100. Fertilization of maize grown under deficit irrigation with N160 increased the grain, straw and biological yield and water use efficiency by 50, 14, 22 and 33% compared with N100. Based on the obtained results, 160?kg of N ha?1 is the optimum rate of N for maize irrigated by 75% of water requirements. 相似文献
100.
Anya Epelbaum Christopher M Pearce Simon Yuan Nadia Plamondon Helen Gurney‐Smith 《Aquaculture Research》2011,42(7):975-986
The basket cockle, Clinocardium nuttallii, is a candidate species for aquaculture in British Columbia, Canada. Previous research on broodstock conditioning, embryonic development and larval rearing of C. nuttallii demonstrated the potential for reliable hatchery production of cockle seed. In this paper, we investigated the effects of culture density (50% and 150% bottom cover in a monolayer) and substratum (none and fine sand) on cockle seed survival, growth, behaviour and shell morphology to improve the efficiency of the nursery production phase. Low stocking density (50% cover) yielded a shell length increase from 3 to 7 mm over a 4‐week period. High stocking density (150% cover) negatively impacted some of the growth and condition parameters studied, but did not have a statistically significant effect on seed survival. Growing seed without substratum did not significantly affect seed survival or growth, but led to shell deformities (at shell length >15 mm) and lower burrowing rates when cockles were subsequently placed on sand. We recommend planting seed for grow‐out at a shell length not exceeding 15 mm. Acclimating seed to the substratum before planting may increase the burrowing rates, thereby reducing the risks of seed dislocation and mortality. Additional studies are required to determine optimal substratum acclimation times and techniques. 相似文献