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391.
Gopesh C. Saha Ashutosh Sarker Weidong Chen George J. Vandemark Fred J. Muehlbauer 《Euphytica》2010,175(2):261-265
Lentil rust caused by Uromyces vicia-fabae (Pers.) Schroet is one of the most important diseases of lentil in South Asia, North Africa and East Africa. This disease
is usually observed during late flowering and early podding stages. Early infection accompanied by favorable environmental
conditions can result in complete crop failure and huge economic losses. Therefore, breeding for resistance against this pathogen
is one of the major challenges for the breeders in those regions. It is important to identify resistance sources and to determine
the location of the genes for resistance in the lentil genome. Since field screening is often difficult due to the unpredictable
nature of the disease, selectable molecular markers can be useful tools to assist lentil breeding and complement field screening
and selection for resistance. To map the genes for resistance, a recombinant inbred line (RILs) population composed of 220
RILs was developed from a cross between a rust resistant line, ILL-4605, and a susceptible line from Bangladesh, ILL-5888.
Phenotyping of the RIL population was carried out during 2006–2007 and 2008–2009 cropping seasons at the Pulse Research Center,
Ishurdi, Bangladesh. There was a lack of uniformity of disease pressure in the 2006–2007 cropping year causing inconsistencies
between replicates. Nevertheless, we were able to choose clearly resistant and clearly susceptible RILs for selective genotyping
using markers previously placed on our lentil genetic map. One of the 62 markers used for selective genotyping proved to be
linked to the gene for resistance. The identified sequence related amplified polymorphism (SRAP) marker, F7XEM4a, was estimated
to be 7.9 cM from the gene for resistance. The F7XEM4a marker could be used for marker assisted selection for resistance;
however, additional markers closer to the resistance gene are needed. 相似文献
392.
Fred Denilson Barbosa da Silva Leonardo Angelo de Aquino Luís Eduardo Panozzo Tricia Costa Lima Paulo Geraldo Berger Denise Cunha Fernandes dos Santos Dias 《Communications in Soil Science and Plant Analysis》2016,47(7):809-817
Sunflower has been mentioned in the literature as a plant that requires large amounts of boron (B) to achieve a successful crop. This study aimed at evaluating the influence of sunflower fertilization with boron on the soil nutrient concentration, index leaf, seed yield, fatty acids’ composition of sunflower oil, and oil content. Cultivar M734 was selected for boron fertilization at 0, 3, 6, 9, and 12 kg ha?1 rates. The maximum economic return was obtained with 3.13 kg ha?1. Neither oil content nor fatty acid composition was affected by boron. With proper irrigation, the M734 cultivar was able to absorb boron in the 0 ? 40-cm layer, ultimately producing about 3000 kg ha?1 of seeds in soils with only 0.30 mg kg?1 of boron. Based on these results, it is suggested that the boron fertilization program be expanded to include the soil strata at 0?20 cm and 20?40 cm. 相似文献
393.
A spatial model of long term habitat succession at a degrading Louisiana wetland was constructed based upon simulating exchanges across irregularly shaped polygons. Polygons represented the natural morphology which is indicative of the natural landscape. The PBS model was partially successful in simulating spatial habitat changes over a 28-year period when more than 1000 ha of wetland loss occurred (r2=.56). General landscape trends did, however, emerge from the model development. Areas of high annual water level fluctuations, and high primary productivity were less likely to change from wetlands to open water and were most likely to recover if altered. We discuss the potential for predictive improvement and for integration with polygon-based geographic information systems, and conclude that a PBS model demonstrates the need for spatially explicit landscape management. 相似文献
394.
The influence of post-treatment temperature on the toxicities of two pyrethroids (lambda-cyhalothrin and bifenthrin), a carbamate (methomyl) and a spinosyn (spinosad) to Ostrinia nubilalis (Hubner) larvae was evaluated in laboratory assays. From 24 to 35 degrees C, the toxicities of the pyrethroids decreased 9.5- and 13.6-fold while spinosad toxicity decreased 3.8-fold. The toxicity of methomyl did not change significantly. The results demonstrate that the most effective insecticide against a pest may vary with environmental conditions. In situations where comparable products from multiple insecticide classes are available, temperature should be included as a factor in the decision-making process. 相似文献
395.
A peptide vaccine administered transcutaneously together with cholera toxin elicits potent neutralising anti-FMDV antibody responses 总被引:2,自引:0,他引:2
Beignon AS Brown F Eftekhari P Kramer E Briand JP Muller S Partidos CD 《Veterinary immunology and immunopathology》2005,104(3-4):273-280
In this study a synthetic peptide representing residues 141-159 from the GH loop of VP1 protein of foot-and-mouth disease virus was tested for its capacity to elicit virus neutralising antibodies in mice after transcutaneous immunisation. Topical application of the peptide conjugated to bovine serum albumin together with cholera toxin as an adjuvant elicited anti-peptide antibody responses with strong virus neutralising activity. The combination of cholera toxin with an immunostimulatory CpG motif resulted in the induction of IgG1 and IgG2a anti-peptide antibodies with significantly enhanced virus neutralising activity. To shed more light on the mechanisms of cholera toxin adjuvanticity we demonstrated its binding to keratinocytes via GM(1)-gangliosides. This was followed by an increase of the intracellular cAMP and the rapid diffusion of cholera toxin throughout the epidermis. These findings demonstrate that peptide-based vaccines when combined with the appropriate adjuvant(s) can elicit potent virus neutralising antibody responses after transcutaneous immunisation. However, experiments in target species will be required to confirm the potential of this simple vaccination procedure in livestock. 相似文献
396.
Solid-state light sources getting smart 总被引:2,自引:0,他引:2
More than a century after the introduction of incandescent lighting and half a century after the introduction of fluorescent lighting, solid-state light sources are revolutionizing an increasing number of applications. Whereas the efficiency of conventional incandescent and fluorescent lights is limited by fundamental factors that cannot be overcome, the efficiency of solid-state sources is limited only by human creativity and imagination. The high efficiency of solid-state sources already provides energy savings and environmental benefits in a number of applications. However, solid-state sources also offer controllability of their spectral power distribution, spatial distribution, color temperature, temporal modulation, and polarization properties. Such "smart" light sources can adjust to specific environments and requirements, a property that could result in tremendous benefits in lighting, automobiles, transportation, communication, imaging, agriculture, and medicine. 相似文献
397.
Efficacy of tulathromycin injectable solution for the treatment of naturally occurring Swine respiratory disease 总被引:4,自引:0,他引:4
Nutsch RG Hart FJ Rooney KA Weigel DJ Kilgore WR Skogerboe TL 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):214-224
Tulathromycin, a novel triamilide antimicrobial, was evaluated for treatment of swine respiratory disease (SRD) in field efficacy studies involving 720 pigs in six North American swine herds. In each study, feeder pigs with clinical SRD were randomly assigned in equal numbers to a group treated with tulathromycin given as a single injection at 2.5 mg/kg of body weight or to a saline-treated control group. Four of the studies included a third group treated with ceftiofur sodium for 3 consecutive days at 3 mg/kg of body weight. Pigs were treated on day 0 and evaluated for treatment response on day 7. In each study, 10 or more nontreated pigs and saline-treated pigs that did not respond to treatment underwent necropsies to obtain lung samples that were evaluated for SRD pathogens. The overall cure rate was 46.4% for saline-treated pigs, 71.1% for tulathromycin-treated pigs, and 63.1% for ceftiofur-treated pigs. The cure rate for tulathromycin-treated pigs was significantly higher than for saline-treated pigs (P = .0116). Mortality from SRD occurred in 24 control pigs, seven tulathromycin-treated pigs, and one ceftiofur-treated pig. The mortality rate was significantly lower for both the tulathromycin- and ceftiofur-treated pigs compared with those treated with saline (P = .0148 and P = .0195, respectively). Actinobacillus pleuropneumoniae, Pasteurella multocida, Haemophilus parasuis, and Mycoplasma hyopneumoniae, bacteria commonly associated with SRD, were isolated from SRD-affected pigs. Under field conditions, tulathromycin injectable solution given as a single IM dose of 2.5 mg/kg of body weight was safe and effective in the treatment of SRD. 相似文献
398.
Caldwell FJ Mueller PO Lynn RC Budsberg SC 《American journal of veterinary research》2004,65(3):271-276
OBJECTIVE: To determine whether 1% diclofenac liposomal suspension (DLS) ointment would be absorbed transdermally and attenuate experimentally induced subcutaneous inflammation in horses. ANIMALS: 7 healthy adult horses. PROCEDURE: Inflammation was produced by injecting 1% sterile carrageenan into subcutaneously implanted tissue cages 8 hours before (time -8) and at the time of application of test ointment. A crossover design was used. Horses received 1 of 2 treatments (topically administered control or DLS ointments) during 48 hours of carrageenan-induced subcutaneous inflammation. A single application of test ointment (7.2 g) was applied over each tissue cage (time 0). Samples of transudate and blood were collected at -8, 0, 6, 12, 18, 24, 30, 36, and 48 hours. Plasma and transudate diclofenac concentrations were determined by use of high-performance liquid chromatography. Transudate concentrations of prostaglandin E2 (PGE2) were determined with a competitive enzyme immunoassay. RESULTS: DLS was absorbed transdermally. The highest concentration (mean +/- SEM, 76.2 +/- 29 ng/mL) was detectable in tissue-cage fluid within 18 hours after application. Minimal concentrations of diclofenac were detectable in plasma. Application of DLS significantly decreased transudate concentrations of PGE2 at 6 and 30 hours. Decreases in PGE2 concentration were observed in the DLS group at all collection times. CONCLUSIONS AND CLINICAL RELEVANCE: A single topical application of DLS resulted in concentrations of diclofenac in transudate within 6 hours and significantly attenuated carrageenan-induced local production of PGE2. Results of this study suggest that DLS is readily absorbed transdermally and may be efficacious for reducing subcutaneous inflammation in horses. 相似文献
399.
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