Studies on the development of a mating disruption system to control the tomato leafminer, Tuta absoluta Povolny (Lepidoptera: Gelechiidae)     

Vacas S  Alfaro C  Primo J  Navarro-Llopis V 《Pest management science》2011,67(11):1473-1480

BACKGROUND: The tomato leafminer (Tuta absoluta Povolny) has rapidly colonised the whole Mediterranean and South‐Atlantic coasts of Spain, and it has become a key problem in both outdoor and greenhouse crops. New control methods compatible with biological control are required, and mating disruption appears to be a perfect method in current agriculture, as it is an environmentally friendly and residue‐free technique. IPM packages tested have included the use of pheromones to detect populations, but there has not been much previous research on mating disruption of T. absoluta. In this work, pheromone doses varying from 10 to 40 g ha^?1, emitted at a constant rate over 4 months, were tested in greenhouses with different levels of containment in order to evaluate the efficacy of mating disruption on T. absoluta. RESULTS: Trials on containment level revealed that the flight of T. absoluta was satisfactorily disrupted with an initial pheromone dose of 30 g ha^?1, and levels of damage did not significantly differ from those in reference plots with insecticide treatments. Later efficacy trials confirmed previous experiences, and release studies showed that control of damage and flight disruption were taking place when releasing at least 85 mg pheromone per ha per day. CONCLUSION: Effective control using pheromone application against T. absoluta can be achieved, in greenhouses with high containment levels, for 4 months, with initial doses of 30 g ha^?1. Further research must be conducted in order to evaluate the prospect of outdoor application of mating disruption systems. Copyright © 2011 Society of Chemical Industry  相似文献   

Potential of Borago officinalis, Sinapis alba L. and Phacelia boratus for Phytoextraction of Cd and Pb from Soil     

Michael W. H. Evangelou  Sandra Kutschinski-Klöss  Mathias Ebel  Andreas Schaeffer 《Water, air, and soil pollution》2007,182(1-4):407-416

Heavy metal phytoextraction is a soil remediation technique, which makes use of plants in removing contamination from soil. The plants must thus be tolerant to heavy metals, adaptable to soil and climate characteristics, and able to take up large amounts of heavy metals. Most of the high biomass productive plants such as, maize, oat and sunflower are plants, which do not grow in cold climates or need intensive care. In this study three “weed” plants, Borago officinalis; Sinapis alba L. and Phacelia boratus were investigated for their ability to tolerate and accumulate high amounts of Cd and Pb. Pot experiments were performed with soil containing Cd and Pb at concentrations of up to 180 mg kg^?1 and 2,400 mg kg^?1 respectively. All three plants showed high levels of tolerance. Borago officinalis; and Sinapis alba L. accumulated 109 mg kg^?1 and 123 mg kg^?1 Cd, respectively at the highest Cd spiked soil concentration. Phacelia boratus reached a Cd concentration of 42 mg kg^?1 at a Cd soil concentration of 100 mg kg^?1. In the case of Pb, B. officinalis and S. alba L. displayed Pb concentrations of 25 mg kg^?1 and 29 mg kg^?1, respectively at the highest Pb spiked soil concentration. Although the Pb uptake in P. boratus reached up to 57 mg kg^?1 at a Pb spiked soil concentration of 1,200 mg kg^?1, it is not suitable for phytoextraction because of its too low biomass.  相似文献   

Hematopoiesis as a competitive exclusion process: Estimation of a stem cell selective advantage     

Sandra?N.?CatlinEmail author  Peter?Guttorp  Monica?T.?McCallie  Janis?L.?Abkowitz 《Journal of Agricultural, Biological & Environmental Statistics》2004,9(2):216-235

Female Safari cats are offspring of domestic and Geoffroy parents, and are balanced heterozygotes with equal numbers of Blood cells containing domestic and Geoffroy-type glucose 6-phosphate dehydrogenase (G6PD),an X-chromosome derived enzyme. In previous studies, however, we observed increasing percentages of Blood cells with Geoffroy G6PD in cats aged 4–12 years. Similarly, ratios of parental X-chromosome phenotypes greater than three to one are common in women over age 60, while women under 40 typically exhibit one to one ratios. Using a two-compartment hidden-Markov model of the distribution of phenotype in samples taken during the second stage of hematopoiesis (Blood cell production), we estimate, through simulation and mathematical calculation, the Geoffroy selective advantages necessary to reproduce the data obtained from female Safari cats. It is shown that small differences in the kinetics of hematopoietic stem cells (HSC), less than might be detected by in vitro assays, can explain the “clonal dominance” observed with aging in cats, and by extension, human females. Conceptually, hematopoiesis in females can be viewed as a competitive exclusion process in which two populations of HSC (defined by parental X-chromosome phenotype) compete for environmental resources. As in many ecological examples, dominance may occur only after long periods of time.  相似文献   

Determination of choline in milk, milk powder, and soy lecithin hydrolysates by flow injection analysis and amperometric detection with a choline oxidase based biosensor     

Pati S  Quinto M  Palmisano F  Zambonin PG 《Journal of agricultural and food chemistry》2004,52(15):4638-4642

A fast-response and interference-free amperometric biosensor based on choline oxidase immobilized onto an electropolymerized polypyrrole film for flow injection determination of choline in milk, milk powder, and soy lecithin hydrolysates is described. The sensor displayed an Imax value of 1.9 +/- 0.2 microA and an apparent Michaelis-Menten constant, k'M, equal to 1.75 +/- 0.07 mM. Detection limits of 0.12 microM could be obtained. Because even a slight deterioration of the anti-interference membrane can adversely affect measurement accuracy, a real time monitoring of the biosensor selectivity has been achieved by a dual Pt electrode flow-through cell where the enzyme modified electrode is coupled to an enzyme-free electrode in a parallel configuration. Finally, bracketing technique (alternate injections of sample and standards) allows a two-point calibration to be performed in real-time, correcting for any drift in sensor response.  相似文献   

Effect of the addition of sewage sludge as a fertilizer on a sandy vineyard soil     

Bravo-Martín-Consuegra  Sandra  García-Navarro  Francisco Jesús  Amorós-Ortíz-Villajos  José Ángel  Pérez-de-los-Reyes  Caridad  Higueras  Pablo L. 《Journal of Soils and Sediments》2016,16(4):1360-1365

Purpose

The application of sludge from wastewater in agriculture has increased in recent years, and it is therefore important to assess the effect that such treatment has on both the soil and the plant. The aim of the study described here was to ascertain whether there is a variation in the properties of the soil and to determine if this addition has an impact on the plant.

Materials and methods

The area of investigation was close to the municipality of Villarrubia de los Ojos (Ciudad Real). In this work, six samples were taken from the surface horizon in the studied plot at a depth of 35 cm. A further three samples were taken: (i) a surface horizon of a soil close to the area under investigation but without treatment (control sample), (ii) a sample of sludge from the wastewater treatment plant and (iii) a sample of the mixture used by farmers as fertilizer. Laboratory tests were conducted in accordance with the SCS-USDA (1972) guidelines. Trace element samples were analysed by X-ray fluorescence spectrophotometry (Philips PW 2404).

Results and discussion

The parcel of land studied is dominated by a sandy texture (88.3 % sand), and a decrease in pH was observed in areas in which the mixture (manure + sludge) was added (pH?=?8.0) compared to areas in which fertilizer was not applied (pH?=?8.5). It was observed that the addition of the compound led to an increase in the electrical conductivity of the soil. The trace elements can be organized into two groups based on the results obtained in this study. One group contains the trace elements that were only present in the rows that were treated with the fertilizer. The other group of trace elements was mobilized throughout the whole plot.

Conclusions

The application of sewage sludge on agricultural soils can be very useful as an organic amendment because it produces an increase in soil organic matter. However, sewage sludge must be applied with caution due to the changes in soil chemical properties (for example, pH and E.C.). The use of this type of waste for prolonged periods of time can cause problems of contamination in the soil.

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Comparative study of the composition of melanoidins from glucose and maltose   总被引：1，自引：0，他引：1  

Mundt S  Wedzicha BL 《Journal of agricultural and food chemistry》2004,52(13):4256-4260

The composition of melanoidins formed in the reactions of either glucose or maltose with glycine (70 degrees C, pH 5.5, [glucose] = [maltose] = [glycine] = 0.25 M) (MW > 3500) was investigated by microanalysis and the use of (14)C-labeled sugars and amino acid. The most reliable parameter obtained from microanalysis data is the C/N value, as it was calculated with no model assumption. The C/N value (7.6 +/- 0.2 for glucose and 10.5 +/- 0.2 for maltose) does not change with molecular weight (MW > 3500) as the polymers grow in size. A comparison between the radiochemically determined composition and that obtained from microanalysis suggests that the amino ketone, which is one of the products of Strecker degradation reaction, forms part of the of the melanoidin structure, together with the sugar-derived moiety and the Strecker aldehyde. Evidence is presented that glucose is formed at intermediate stages of the maltose-glycine reaction. The melanoidins are the result of the polymerization of glucose and intact, or substantially intact, maltose residues with glycine.  相似文献   

Eucharis Grandiflora Planch. and Linden Development Fertirrigated with Different Osmotic Potentials     

Silvia Evangelista-Lozano  Maribel Estrada-García  Sandra Luz Escobar-Arellano  Martha Lucia Arenas-Ocampo  Brenda Hildeliza Camacho-Díaz 《Journal of plant nutrition》2015,38(4):551-567

Eucharis grandiflora Planch. and Linden is a tropical climate Amaryllidacea, commonly known as lily, which develops a bulbous stem and is considered an indoor ornamental plant for its evergreen foliage and inflorescence. The aim of this study was to evaluate the vegetative development of the Lily, in response to the treatment with of the Steiner solution at different concentrations. The plants were acclimated under greenhouse conditions and the bulbs selected by a completely randomized design. Plants were treated with various concentrations of the Steiner solution, to develop the following potential osmotic: ?0.018, ?0.036, ?0.054, ?0.072, and 0 Mpal. The production of bulbils, development and leaf area, stomatal density, chlorophyll quantification, and osmotic potentials were evaluated. The results showed that treatment with solutions of ?0.054 and ?0.072 MPa induced a greater vegetative growth, 29.5% more stomata developed, and synthesized 29% more chlorophyll “b” than the control.  相似文献   

The Adventures of Dr. Duncan McNab McEachran in Western Canada          下载免费PDF全文

Sandra Vokaty 《The Canadian veterinary journal. La revue veterinaire canadienne》1979,20(6):149-156

Duncan McNab McEachran's early history and involvement in the formation of the Montreal Veterinary College as well as in livestock inspection were reviewed. His contribution to the beginning of the ranching industry in western Canada was explored in detail. In 1881, McEachran helped to establish the Cochrane Ranche, which was the first great ranch to be started in southern Alberta. He was employed as the ranch's resident general manager until 1883, in which year the Waldrond Ranch was established. McEachran was this ranch's president and general manager until approximately 1909. During this time, he came under considerable criticism from both The MacLeod Gazette and The Calgary Herald. As Dr. McEachran maintained his obligations to the ranches while he was directing the veterinary college in Montreal as well as chief inspector of livestock for Canada, it was concluded that this feat alone would rank him as a remarkable historical figure.  相似文献   

Animal welfare--the need for a united veterinary voice     

Neumann S 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(9):834-836

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Frequency of urinary tract infection among dogs with pruritic disorders receiving long-term glucocorticoid treatment     

Torres SM  Diaz SF  Nogueira SA  Jessen C  Polzin DJ  Gilbert SM  Horne KL 《Journal of the American Veterinary Medical Association》2005,227(2):239-243

OBJECTIVE: To determine frequency of urinary tract infection (UTI) among dogs with pruritic disorders that were or were not receiving long-term glucocorticoid treatment. DESIGN: Observational study. ANIMALS: 127 dogs receiving glucocorticoids for > 6 months and 94 dogs not receiving glucocorticoids. PROCEDURE: Bacterial culture of urine samples was performed in dogs receiving long-term glucocorticoid treatment, and information was collected on drug administered, dosage, frequency of administration, duration of glucocorticoid treatment, and clinical signs of UTI. For dogs not receiving glucocorticoids, a single urine sample was submitted for bacterial culture. RESULTS: Multiple (2 to 6) urine samples were submitted for 70 of the 127 (55%) dogs receiving glucocorticoids; thus, 240 urine samples were analyzed. For 23 of the 127 (18.1%) dogs, results of bacterial culture were positive at least once, but none of the dogs had clinical signs of UTI. Pyuria and bacteriuria (present vs absent) were found to correctly predict results of bacterial culture for 89.9% and 95.8% of the samples, respectively. Type of glycocorticoid, dosage, frequency of administration, and duration of treatment were not associated with frequency of UTI. None of the urine samples from dogs not receiving glucocorticoids yielded bacterial growth. The frequency of UTI was significantly higher for dogs treated with glucocorticoids than for dogs that had not received glucocorticoids. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dogs receiving long-term glucocorticoid treatment have an increased risk of developing a UTI. On this basis, we recommend that urine samples be submitted for bacterial culture at least yearly for such dogs.  相似文献