Petiole N,P, K Concentrations and Yield of the Potato Cultivar Molli from Certified Organic Amendments and Fertilizer Formulations     

H.P. Collins  L. Porter  R.A. Boydston  A. Alva  B. Chaves Cordoba 《Communications in Soil Science and Plant Analysis》2016,47(10):1227-1238

This study evaluated the petiole uptake of nitrogen, phosphorus, potassium, and sulfur (N, P, K, and S) by the potato from two seed meals, mint compost, and five commercially available organic fertilizers under an irrigated certified organic production system. Available soil nitrate (NO₃-N) and ammonium (NH₄-N) from each amendment averaged 115 kg N ha^?1 at application and 25 kg N ha^?1 30 d after planting through harvest, with minor differences between fertilizers. Petiole N declined from an average of 25,000 mg N kg^?1, 4 wk after emergence to 3,000 mg N kg^?1 prior to harvest. Petiole P and K concentrations were maintained above 4,000 mg P kg^?1, 10,000 mg K kg^?1, and 2,000 mg S kg^?1 tissue, respectively, throughout the growing season in all treatments. Tuber yields were not different between fertilized treatments averaging 53 Mg ha^?1. This study provides organic potato growers baseline information on the performance of a diverse array of organic fertilizers and amendments.  相似文献   

Performance of legume–grass mixtures in the West Balkan region     

Branko Ćupina  Svetlana Vujić  Branko Djurić  Sali Aliu  Maja Manojlović 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(1):1-11

Three perennial legumes (alfalfa, red clover and birdsfoot trefoil) and four cool-season perennial grasses (orchardgrass, tall fescue, Italian ryegrass and red fescue) were grown in legume–grass combinations and in pure stands of individual species, at three locations in the West Balkan region (Novi Sad, Banja Luka and Pristina) in the period from 2012 to 2015. The study evaluated dry matter yield, legume–grass–weed proportion and forage quality. High annual forage yield of legume–grass mixtures can be obtained with proper selection of species and an appropriate legume–grass ratio. However, high and stable yield, particularly in the case of grasses, depends on the amount and schedule of precipitation as well as the cutting time. The mixtures and legume pure stands achieved better forage production both per cutting and on the annual basis and had better forage quality than grass pure stands.  相似文献   

Concentration of trace and major elements in natural grasslands of Bosnia and Herzegovina in relation to soil properties and plant species     

Jasmina Vejnovic  Branko Djuric  Peder Lombnæs  Bal Ram Singh 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(3):243-254

Deficient trace elements concentration in soils, forages, and animals have been reported in several areas of Balkan region. Main challenge in overcoming low productivity of forage and animal production in this region is the lack of data on the nutritional status of the pastures and soils. This study examined the nutrient and pseudo total concentration of trace elements in soil and herbage plants, and the potential deficiency or excess with regards to crop and livestock production. Soil and plant samples from 100 sampling points were collected in the mountainous grasslands of Manja?a (between longitudes 16°56′ and 17°8′ east; and latitudes 44°33′ and 44°42′ north) and Vla?i? (between longitudes 17°14′ and 17°29′ east; and latitudes 44°25′ and 44°37′ north). Soil samples were analysed for soil texture, pseudo total concentration (5?ml HNO₃) of trace elements (TE), pH, soil organic carbon (SOC), while plant samples were analysed for TE. The soil pH varied from strongly acidic to moderately alkaline. The concentration of SOC varied from 0.5% to 12.3%. Most of the soil samples were finer-textured soils high in silt content. The average concentrations of Na, P, Zn, Se, Cu, Co, and B were low in both soil and herbage plants. Plant K, Ca, Mg, Mo, and Mn concentrations were sufficiently high to meet the requirements of grazing animals, while Fe concentrations was elevated in certain areas. High levels of Mo were found in both soil and plants. The results suggest that imbalances observed in natural pastures of Manja?a and Vla?i? area, caused by low soil TE concentration and other soil and plant properties, could contribute to poor animal nutrition.  相似文献   

Effects of Biochar and Biosolid on Adsorption of Nitrogen,Phosphorus, and Potassium in Two Soils     

H. Rens  T. Bera  A. K. Alva 《Water, air, and soil pollution》2018,229(8):281

Increasing the retention of nutrients by agricultural soils is of great interest to minimize losses of nutrients by leaching and/or surface runoff. Soil amendments play a role in nutrient retention by increasing the surface area and/or other chemical processes. Biochar (BC) is high carbon-containing by-product of pyrolysis of carbon-rich feedstocks to produce bioenergy. Biosolid is a by-product of wastewater treatment plant. Use of these by-products as amendments to agricultural soils is beneficial to improve soil properties, soil quality, and nutrient retention and enhance carbon sequestration. In this study, the adsorption of NH₄-N, P, and K by a sandy soil (Quincy fine sand (QFS)) and a silty clay loam soil (Warden silty loam (WSL)) with BC (0, 22.4, and 44.8 mg ha^?1) and biosolid (0 and 22.4 mg ha^?1) amendments were investigated. Adsorption of NH₄-N by the QFS soil increased with BC application at lower NH₄-N concentrations in equilibrium solution. For the WSL soil, NH₄-N adsorption peaked at 22.4 mg ha^?1 BC rate. Biosolid application increased NH₄-N adsorption by the WSL soil while decreased that in the QFS soil. Adsorption of P was greater by the WSL soil as compared to that by the QFS soil. Biosolid amendment significantly increased P adsorption capacity in both soils, while BC amendment had no significant effects. BC and biosolid amendments decreased K adsorption capacity by the WSL soil but had no effects on that by the QFS soil. Ca release with increasing addition of K was greater by the WSL soil as compared to that by the QFS soil. In both the soils, Ca release was not influenced by BC amendment while it increased with addition of biosolid. The fit of adsorption data for NH₄-N, P, and K across all treatments and in two soils was better with the Freundlich model than that with the Langmuir model. The nutrients retained by BC or biosolid amended soils are easily released, therefore are readily available for the root uptake in cropped soils.  相似文献   

Evaluation of fipronil spot-on in the treatment of flea allergic dermatitis in dogs     

Medleau L  Clekis T  McArthur TR  Alva R  Barrick RA  Jeannin P  Irwin J 《The Journal of small animal practice》2003,44(2):71-75

The purpose of this study was to evaluate the effectiveness of treatment with 10 per cent fipronil solution for controlling signs of flea allergic dermatitis in dogs under field conditions. Thirty-one client-owned dogs with flea allergic dermatitis were treated with three monthly applications of 10 per cent fipronil solution. Flea counts and pruritus were significantly reduced at all post-treatment visits. At the final visit, on day 90, flea counts were reduced by 98 per cent, and pruritus was reduced or eliminated in 84 per cent of the study dogs. Dermatological lesion scores for erythema, crusts, scales and papules were also significantly improved by the final visit. The overall assessment of efficacy on day 90 was 'excellent' to 'good' for 87 per cent of the study dogs. The results demonstrate that treatment with monthly topical applications of 10 per cent fipronil solution is effective in reducing the prevalence and severity of signs of flea allergic dermatitis in dogs.  相似文献   

Effect of topical application of fipronil in cats with flea allergic dermatitis     

Medleau L  Hnilica KA  Lower K  Alva R  Clekis T  Case J  McArthur TR  Barrick RA  Jeannin P  Irwin J 《Journal of the American Veterinary Medical Association》2002,221(2):254-257

OBJECTIVE: To determine whether topical application of a 10% fipronil solution would control signs of flea allergic dermatitis in cats housed under natural conditions. DESIGN: Multicenter open clinical trial. ANIMALS: 42 client-owned cats with flea allergic dermatitis. PROCEDURES: Study cats along with all other cats and dogs living in the same houses were treated with 10% fipronil solution topically on days 0, 30, and 60. Flea counts and clinical assessments were performed on study cats on days 0, 14, 30, 60, and 90. RESULTS: Percentage reductions in geometric mean flea counts on days 14, 30, 60, and 90, compared with day-0 geometric mean count, were 75, 73, 85, and 94%, respectively. Pruritus score was significantly improved at each examination after day 0, and pruritus was reduced or eliminated in 31 of 40 (78%) cats at the final examination. Similarly, scores for severity of miliary dermatitis and alopecia were significantly improved at each examination, except for alopecia score on day 14. Overall treatment efficacy, assessed on day 90, was excellent for 28 (70%) cats, good for 6 (15%), moderate for 3 (7.5%), and poor for 3 (7.5%). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that monthly topical application of fipronil is effective for treatment of flea allergic dermatitis in cats housed under natural conditions.  相似文献   

Nitrogen uptake and growth of two citrus rootstock seedlings in a sandy soil receiving different controlled-release fertilizer sources   总被引：4，自引：0，他引：4  

H. Dou  A. K. Alva 《Biology and Fertility of Soils》1998,26(3):169-172

Understanding the fate of different forms of nitrogen (N) fertilizers applied to soils is an important step in enhancing N use efficiency and minimizing N losses. The growth and N uptake of two citrus rootstocks, Swingle citrumelo (SC), and Cleopatra mandarin (CM), seedlings were evaluated in a pot experiment using a Candler fine sand (hyperthermic, uncoated, Typic Quartzipsamments) without N application or with 400 mg N kg^–1 applied as urea or controlled-release fertilizers (CRF; either as Meister, Osmocote, or Poly-S). Meister and Osmocote are polyolefin resin-coated urea with longevity of N release for 270 days (at 25°C). Poly-S is a polymer and sulfur-coated urea with release duration considerably shorter than that of either Meister or Osmocote. The concentrations of 2 M KCl extractable nitrate nitrogen (NO₃ ^–-N) and ammonium nitrogen (NH₄ ⁺-N) in the soil sampled 180 days and 300 days after planting were greater in the soil with SC than with CM rootstock seedlings. In most cases, the extractable NH₄ ⁺ and NO₃ ^– concentrations were greater for the Osmocote treatment compared to the other N sources. For the SC rootstock seedlings, dry weight was greater with Meister or Poly-S compared with either Osmocote or urea. At the end of the experiment, ranking of the various N sources, with respect to total N uptake by the seedlings, was: Meister = Osmocote > Poly-S > Urea > no N for CM rootstock, and Meister = Poly-S = Osmocote > Urea > no N for SC rootstock. The study demonstrated that for a given rate of N application the total N uptake by seedlings was greater for the CRF compared to urea treatment. This suggests that various N losses were lower from the CRF source as compared to those from soluble fertilizers. Received: 11 April 1997  相似文献   

First application of a microsphere-based immunoassay to the detection of genetically modified organisms (GMOs): quantification of Cry1Ab protein in genetically modified maize     

Fantozzi A  Ermolli M  Marini M  Scotti D  Balla B  Querci M  Langrell SR  Van den Eede G 《Journal of agricultural and food chemistry》2007,55(4):1071-1076

An innovative covalent microsphere immunoassay, based on the usage of fluorescent beads coupled to a specific antibody, was developed for the quantification of the endotoxin Cry1Ab present in MON810 and Bt11 genetically modified (GM) maize lines. In particular, a specific protocol was developed to assess the presence of Cry1Ab in a very broad range of GM maize concentrations, from 0.1 to 100% [weight of genetically modified organism (GMO)/weight]. Test linearity was achieved in the range of values from 0.1 to 3%, whereas fluorescence signal increased following a nonlinear model, reaching a plateau at 25%. The limits of detection and quantification were equal to 0.018 and 0.054%, respectively. The present study describes the first application of quantitative high-throughput immunoassays in GMO analysis.  相似文献   

Efficacy and safety of firocoxib in the management of canine osteoarthritis under field conditions     

Hanson PD  Brooks KC  Case J  Conzemius M  Gordon W  Schuessler J  Shelley B  Sifferman R  Drag M  Alva R  Bell L  Romano D  Fleishman C 《Veterinary therapeutics : research in applied veterinary medicine》2006,7(2):127-140

A total of 249 client-owned dogs with osteoarthritis were treated with firocoxib (5 mg/kg/day) or a positive control, etodolac (10-15 mg/kg/day), for 30 days. Veterinary examinations were performed on approximately days 0 (visit 1), 14 (visit 2), and 29 (visit 3). Based on defined noninferiority criteria, firocoxib and etodolac were comparable. Based on the magnitude of the change from baseline, improvement with firocoxib was significantly greater than with etodolac for lameness at a trot (visits 2 and 3) and for lameness at a walk, pain on manipulation, and range of motion (visit 3) (P < .05). In weekly owner evaluations, firocoxib provided significantly greater improvement than etodolac (P < .05) at each scoring.  相似文献   

An atypical biotype I Actinobacillus pleuropneumoniae serotype 13 is present in North America     

Perry MB  Angen Ø  MacLean LL  Lacouture S  Kokotovic B  Gottschalk M 《Veterinary microbiology》2012,156(3-4):403-410

Atypical Actinobacillus pleuropneumoniae serotype 13 strains present in North America are described here for the first time. Different from serotype 13 strains described in Europe, North America strains are biotype I and antigenically related to both, serotypes 13 and 10. Chemical and structural analysis of the capsular polysaccharide (CPS) and lipopolysaccharide (LPS) of a representative strain revealed that the CPS is almost identical to that of the reference strain of serotype 13, having a slightly higher degree of glycose O-acetylation. However, it produces an O-PS within the LPS antigenically and structurally identical with that of the reference strain of A. pleuropneumoniae serotype 10. The O-PS was characterized as a homopolymer of 1,2 linked β-D-galactofuranosyl residues, a structure unrelated to that of the O-PS produced by the reference strain of serotype 13. Strains from Canada and United States are antigenically, phenotypically and genotypically similar. Animals infected by one of these strains induced antibodies that were detected by a LPS-based ELISA diagnostic test using either the homologous antigen or that of serotype 10. Based on the LPS and toxin profile, these strains might be misidentified as A. pleuropneumoniae serotype 10.  相似文献