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111.
David Wm. Reed 《Journal of plant nutrition》2013,36(8):667-677
Various glues and adhesives were tested for their ability to remove the unabsorbed residue from drops of foliar applied radioactive nutrients to Ficus benjamina L. and Glycine max Merr. Most glues/adhesives adequately removed the unabsorbed residue from nutrients that dried forming a salt deposit on the leaf surface, but only 1.6–3.2% agar, Rhoplex 33, and Elmers Glue removed greater than 95% of the residue from nutrients that formed a moist hygroscopic residue on the leaf surface. Adding 25 mM KH2PO4 to 3.2% agar, followed by swabbing the treated area with lN HCl‐1% Liquinox detergent removed all unabsorbed residue from monovalent and divalent cationic an anionic nutrients including heavy metals. Methods to assay foliar absorption were compared by applying “Rb phosphate to leaves of intact plants, excised leaves and leaf discs. Excised leaves with their petiole or stem bases in water behaved similar to intact plants, whereas excised leaves or discs maintained in in a moist atmosphere behaved atypically due to slower and incomplete drying compared to intact plants. 相似文献
112.
Extraction of Fe from fresh leaves with 0.1 N HCl proved to be a better indicator of the Fe status of a variety of ornamental tropical foliage and flowering plants compared to total Fe, 0.1 N HCl‐ether, and IN HCl extraction. It consistently gave higher correlations (r = 0.73 to 0.95 depending on the species) with chlorophyll concentration than the other methods tested. However, even 0.1 N HCl extraction did not distinguish levels of Fe deficiency accurately when compared between species. 相似文献
113.
In a series of experiments, plants of Salvia splendens ’St. John's Fire’ were sprayed to run‐off with NH4NO3 solutions that varied from 0.10–1.87 M (0.8–15.0% NH4NO3). Damage to young fully expanded leaves was determined by measuring percent visually estimated necrosis, leakage of UV (264 nm) absorbing constituents, K, Ca and phosphate, and post‐treatment dry weight:fresh weight ratio. The average correlation coefficient of percent visually estimated necrosis was 0.992 with leakage of UV absorbing constituents, 0.956 with leakage of phosphate, 0.951 with dry weightfresh weight ratio, 0.919 with leakage of Ca and 0.741 with leakage of K. Leakage of UV absorbing constituents consistently provided the best correlation with the visual degree of leaf burn. 相似文献
114.
Yan Shi David H. Byrne David Wm. Reed Richard H. Loeppert 《Journal of plant nutrition》2013,36(6):1039-1046
For dicots, bicarbonate (HCO3‐) is regarded as a main factor in the induction of iron (Fe) chlorosis in calcareous soils, and sand and solution culture. In sand culture experiments, peach [Prunus persica (Batsch) L.] rootstock developed chlorosis only when HCO3‐ levels were equal to or higher than 6 mM. Above this level, chlorosis increaeed as HCO3‐ level was increased. In spite of the lack of chlorosis at to or below 6 mM of HCO3‐, large growth reductions (40–60% reduction in fresh shoot weight) were seen in all rootstocks, although the tolerant rootstock had less reduction than the more susceptible rootstocks. Shoot growth was affected by HCO3‐ more than was root growth. 相似文献
115.
Recent attempts to address land degradation have seen calls for greater integration of scientific expertise with local knowledges. In this paper we investigate the potential for such combined understandings to enhance the accuracy, coverage and relevance of land degradation assessment. We followed a participatory approach, using methods from a variety of disciplines, to elicit potential land degradation indicators from communities in Botswana and Swaziland. These indicators were then assessed according to local and scientific understandings. We noted a significant overlap between scientific and local knowledges about land degradation in most instances. Where discrepancies occurred, the integrated participatory approach we used allows appropriate explanation to be reached, supporting the case that such an iterative process can lead to both accurate and relevant monitoring of land degradation. However, the incorporation of integrated knowledges into national policy has not been widespread in either country, suggesting that much greater efforts are required to institutionalise participatory land degradation assessment methodologies. Powerful, often neo‐Malthusian narratives of degradation continue to dominate policy discourse and limit the extent to which hybrid combined local and scientific knowledges can enhance land degradation assessment on a national and regional scale. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
116.
117.
Treatment of atrial fibrillation in horses by intravenous administration of quinidine 总被引:1,自引:0,他引:1
W W Muir S M Reed S M McGuirk 《Journal of the American Veterinary Medical Association》1990,197(12):1607-1610
Intravenous administration of quinidine gluconate converted atrial fibrillation (AF) to sinus rhythm in 9 of 12 horses. Twelve horses that were diagnosed by ECG to have AF were administered up to 11 mg of quinidine gluconate/kg of body weight in 1.0- to 1.5-mg/kg bolus injections every 10 to 15 minutes. The total dose of quinidine administered IV ranged from 1.8 to 5.8 g. Increased ventricular rate, apprehension, and mild depression were observed during treatment. Other signs of toxicosis were not observed. One horse was successfully treated with IV administered quinidine gluconate on 3 occasions. Intravenous administration of quinidine is a safe and effective alternative for treatment of AF in some horses. 相似文献
118.
R A Nicholas N E Reed G W Wood C N Hebert J C Muskett D H Thornton 《Research in veterinary science》1985,38(2):189-192
Four different oil emulsion infectious bursal disease virus (IBDV) vaccines were inoculated into four-week-old specific pathogen-free chickens. At weekly intervals for five weeks, sera were obtained from the vaccinated birds and from uninoculated control birds and examined for antibodies against IBDV by enzyme-linked immunosorbent assay (ELISA), the quantitative agar gel precipitin (QAGP) test and the virus neutralisation (VN) test. There was a highly significant correlation between the mean responses to all tests; the highest correlation (0.818) was between VN and QAGP and the lowest (0.573) between QAGP and ELISA. Generally the ELISA detected positive sera earlier than the VN test which in turn was more sensitive than the QAGP test. The ELISA and QAGP test were less variable, more reproducible and easier to perform than the VN test. 相似文献
119.
Light microscopic and ultrastructural characterization of cells recovered by respiratory-tract lavage of 2- and 6-week-old chickens 总被引:1,自引:0,他引:1
This study characterized the cell population recovered by respiratory-tract lavage of 57 two-week-old and 59 six-week-old specific-pathogen-free chickens as a prerequisite to study the response of the avian respiratory tract to infectious agents. The respiratory tract of each bird was lavaged through the trachea with a series of three lavages of 10 ml of room-temperature, neutral phosphate-buffered saline per lavage. The three lavages per bird were pooled for analysis. Total recovery volumes were measured, lavage fluid cellularity was determined, and a 200-cell differential count of non-erythrocyte cells was performed. Lavage fluid recovery was greater from 2-week-old birds (91.3 percent) than from 6-week-old birds (86.3 percent). Total cells recovered were greater for 6-week-old chickens (6.79 x 10(5)) than for 2-week-old chickens (5.03 x 10(5)). Cells of epithelial origin included squamous cells, goblet cells, and both ciliated and non-ciliated columnar epithelial cells. Cells of non-epithelial origin consisted of heterophils, lymphocytes, macrophages, eosinophils, basophils, and erythrocytes. Cells of epithelial origin were the predominant cell type recovered from the 2-week-old chickens, followed by heterophils. In 6-week-old chickens, heterophils were the predominant cell type recovered, followed by cells of epithelial origin. In descending order of prevalence, the remainder of cell types recovered from chickens of both ages were lymphocytes, macrophages, eosinophils, and basophils. 相似文献
120.
J A Angell J N Shively R E Merideth R E Reed K C Jamison 《Journal of the American Veterinary Medical Association》1985,187(2):167-169
Enucleation of the right eye was performed on a 12-year-old male Persian cat when therapy for uveitis failed. Histologic examination of the anterior and posterior chambers and the vitreous led to a diagnosis of endophthalmitis caused by Coccidioides immitis infection. The primary focus of infection was not determined. Latex particle agglutination, agar gel immunodiffusion, and complement fixation gave negative results for Coccidioides immitis antibody. 相似文献