Messiga A.J.,Agriculture and Agri Food Canada |
Messiga A.J.,Laval University |
Ziadi N.,Agriculture and Agri Food Canada |
Morel C.,French National Institute for Agricultural Research |
And 4 more authors.
Field Crops Research | Year: 2012
The benefits of no till (NT) management in the short to medium terms need to be examined over decades of continuous cropping. Our objectives were to (i) assess the long term effects of tillage practices (no-till (NT) and mouldboard plough [MP]) and biennial P×N fertilizer rates applied to the maize phase of a two-year maize-soybean rotation on grain yield, Mehlich-3 P (PM3), and Olsen P (POl), and (ii) determine whether NT practice affects the relationships between PM3, POl and P budgets. The study site was established in 1992 on a clay loam soil of the St-Blaise series (Dark Grey Gleysol). The experimental design is a split plot with NT and MP assigned to main plots and nine combinations of 3 P (0, 17.5, and 35kg Pha-1) and 3N (0, 80, and 160kg Nha-1) additions assigned to subplots. Maize and soybean grain yield response to P additions was obtained only twice between 1992 and 2010. On average, grain yields were reduced by 10-25% in NT compared to MP treatments in 11 years. The dynamics over years of PM3 and POl (0-15cm) in unfertilized P treatment was similar in NT and MP. In contrast, P fertilized NT maintained greater PM3 and POl than MP. This difference in soil tests P was due to greater P accumulation in the 0-5cm and 5-10cm soil layers of NT. Under MP, soil tests P and P budgets over the P treatments were linearly related and for this specific MP treatment, we calculated that a P budget of ±100kg Pha-1 would change PM3 by 12kgha-1 and POl by 7kgha-1. Under NT, a cubic model fitted closely to the experimental data due principally to a more than proportional change in soil tests P relative to P budgets in fertilized P treatments. We conclude that additions of P fertilizer in NT systems changes the dynamics of P in the rooting zone, suggesting the importance of approaches to monitor P dynamics specifically tailored for NT systems that integrates the variability caused by the absence of mixing the fertilizer, residues, and soil. © 2012 .
Lu W.,CAS Nanjing Institute of Soil Science |
Ding W.,CAS Nanjing Institute of Soil Science |
Zhang J.,CAS Nanjing Institute of Soil Science |
Li Y.,Agriculture |
And 3 more authors.
Soil Biology and Biochemistry | Year: 2014
Conversion of plant residues to biochar is an attractive strategy for mitigation of atmospheric carbon dioxide (CO2) emission and enhancement of carbon (C) storage in soil. However, the effect of biochar application on the decomposition of soil organic C (SOC) as well as its mechanisms is not well understood in the sandy loam soil of North China Plain. We investigated how biochar affected the decomposition of native SOC, using stable δ13C isotope analyses by applying biochar produced from corn straw (a C4 plant, δ13C=-11.9 0/00) to a sandy loam soil (δ13C of SOC=-24.5) under a long-term C3 crop rotation. The incubation experiment included four treatments: no amendment (Control), biochar amendment (BC, 0.5% of soil mass), inorganic nitrogen (N) amendment (IN, 100mgNkg-1) and combined biochar and N amendments (BN). Compared with Control, N amendment significantly (P<0.05) increased total soil CO2 emission, even when combined with biochar amendment. In contrast, biochar alone amendment did not affect total soil CO2 emission significantly. However biochar, even when combined with N amendment, significantly (P<0.05) reduced CO2 emission from native SOC by 64.9-68.8%, indicating that biochar inhibited the decomposition of native SOC and the stimulation effect of inorganic N on native SOC degradation, a negative priming effect. N addition immediately stimulated the growth of microorganisms and altered microbial community structure by increasing Gram-positive bacteria compared to Control as measured by phospholipid fatty acid. Biochar amendment did not alter microbial biomass during the 720-h incubation period except at 168 and 720h, but significantly (P<0.05) lowered dissolved organic C (DOC) content in soil, primarily due to sorption of DOC by the biochar. Our study suggested that biochar application could effectively reduce the decomposition of native organic C and a potential effective measure for C sequestration in the test soil of the North China Plain. © 2014 Elsevier Ltd.
PubMed | Animal and Plant Health Agency, Agriculture, UK Environment Agency, U.S. Department of Agriculture and City University of Hong Kong
Type: Journal Article | Journal: PloS one | Year: 2015
Conflicts between human interests and feral cattle in Hong Kong derive from growing numbers of free-roaming cattle. Public antipathy towards lethal population control led the local authorities to consider fertility control to reduce cattle numbers. This study assessed the potential side effects of the immunocontraceptive GonaCon on individual female cattle and established the effectiveness of GonaCon to induce infertility. We evaluated GonaCon in 34 captive cattle assigned to four groups: Control administered a sham solution; Webbed (surgically sterilized through removal of the oviducts), administered one dose of GonaCon; Webbed, administered one dose of GonaCon and a booster dose three months later, and Treated, administered one dose of GonaCon. The side effects of GonaCon were assessed by monitoring injection site, body weight, body condition, size of lymph nodes, body temperature, and feeding behaviour 1 week and 1, 3, 6, 9 and 12 months after vaccination and by haematological and biochemical variables at vaccination and three months post-vaccination. The effectiveness of GonaCon to cause infertility was monitored by quantifying anti-GnRH antibody titres and by using kits to detect cycling and pregnancy. GonaCon-treated cattle showed no injection site reaction, limping, or abnormal behaviour. No differences were observed in all physiological and welfare indicators between control and vaccinated cattle. All control cattle and 4 of the 12 cattle in the Treated group became pregnant. Cattle administered a booster dose had higher anti-GnRH antibody titres than cattle that received one dose. We concluded that GonaCon does not compromise the animals welfare and is effective in reducing fertility in cattle. A booster dose is likely to increase the duration of infertility. Further studies are required to assess the feasibility and costs of immunocontraception for controlling free-roaming cattle populations.
Kavitha C.,Agriculture |
Rajamani K.,HC and RI |
Journal of Medicinal Plants Research | Year: 2010
Coleus forskohlii is an important indigenous medicinal plant in India. It has been used in traditional Ayurvedic medicine for curing various disorders and this is the only source of the diterpenoid forskolin. Forskolin is used for the treatment of eczema, asthma, psoriasis, cardiovascular disorders and hypertension, where decreased intracellular cAMP level is believed to be a major factor in the development of the disease process. A comprehensive account of the morphology, distribution, medicinal uses, phytochemistry, pharmacological activities, analytical methods, cultivation aspects and biotechnological approaches for forskolin production reported are included in view of the many recent findings of importance on this plant. © 2009 Academic Journals.
Wong S.S.Y.,University of Hong Kong |
Teng J.L.L.,University of Hong Kong |
Poon R.W.S.,University of Hong Kong |
Choi G.K.Y.,University of Hong Kong |
And 4 more authors.
Vector-Borne and Zoonotic Diseases | Year: 2011
There are no comprehensive studies on the performance of commonly used point-of-care diagnostic enzyme immunoassay for common arthropod-borne canine pathogens. A comparative evaluation of an immunochromatographic test for these infections with a comprehensive polymerase chain reaction (PCR) test panel was performed on 100 pet dogs and 100 stray dogs without obvious clinical symptoms. Of the 162 positive test results from both immunochromatographic test and PCR, there was 85.2% concordance. The 24 discordant results between serology and PCR occurred in tests involving Ehrlichia canis (14) and Anaplasma platys (10), which may be related to the time of infection. No positive cases of borreliosis or rickettsiosis were detected. One important limitation of the immunochromatographic test was its lack of testing for babesiosis and hepatozoonosis. The former is the most prevalent arthropod-borne canine infection in our cohort (41%). Coinfections were found in 19% stray dogs and 6% of pet dogs with both tests (p<0.01). Seventeen and 8 samples from stray and pet dogs, respectively, were initially positive in the PCR test for Ehrlichia. However, on sequencing of the PCR amplicon, 10 from stray and 2 from pet dogs were found to be Wolbachia sequences instead, with 100% nucleotide identity to the 16S rRNA sequence of Wolbachia endosymbiont of Dirofilaria immitis. The presence of Wolbachia DNAemia (6%) correlated well with the molecular test and immunochromatographic antigen test for D. immitis. © Copyright 2011, Mary Ann Liebert, Inc.
PubMed | Japanese National Research Institute of Brewing and Agriculture
Type: | Journal: Food chemistry | Year: 2016
A method for detecting the undeclared addition of acidic ingredients is required to control the authenticity of Japanese apricot liqueur. We developed an analytical procedure that minimizes carbon isotope discrimination for measurement of the (13)C values of citric and malic acid isolated from Japanese apricot liqueur. Our results demonstrated that freeze-drying is preferable to nitrogen spray-drying, because it does not significantly affect the (13)C values of citric acid and results in smaller isotope discrimination for malic acid. Both 0.1% formic acid and 0.2% phosphoric acid are acceptable HPLC mobile phases for the isolation of citric and malic acid, although the (13)C values of malic acid exhibited relatively large variation compared with citric acid following isolation using either mobile phase. The developed procedure allows precise (13)C measurements of citric and malic acid isolated from Japanese apricot liqueur.
Bartz F.E.,North Carolina State University |
Cubeta M.A.,North Carolina State University |
Toda T.,Akita Prefectural University |
Naito S.,Agriculture |
Ivors K.L.,North Carolina State University
Plant Disease | Year: 2010
A tomato (Solanum lycopersicum) foliar blight disease of unknown etiology was observed in North Carolina (NC) during 2005 to 2006. Symptoms included necrotic lesions and blighted leaves, with signs of white mycelial growth on abaxial leaf surfaces. The morphology of isolates from symptomatic leaves was consistent with that of Rhizoctonia solani. Because the pattern of symptom expression suggested that basidiospores were the primary inoculum source, Koch's postulates were fulfilled using a method to generate basidiospores in planta. Isolates were characterized by morphology, DNA sequence analysis, hyphal anastomosis, and somatic hyphal interactions. Phylogenetic analyses and hyphal anastomosis criteria support placement of the isolates in R. solani anastomosis group 3 (AG-3). Tomato foliar blight isolates from NC form a single phylogenetic group with tomato isolates of R. solani AG-3 from Japan and are more closely related to R. solani AG-3 isolates from potato than tobacco. Isolates exhibited both compatible and incompatible hyphal interactions when paired in vitro. To our knowledge, this is the first detailed report of tomato foliar blight caused by R. solani AG-3 in North America. A comprehensive description of the technique employed for producing basidiospores is presented with potential utility for understanding foliar disease etiology in other Rhizoctonia pathosystems. © 2010 The American Phytopathological Society.
Izumi B.T.,Portland State University |
Alaimo K.,Michigan State University |
Journal of Nutrition Education and Behavior | Year: 2010
Objective: This qualitative study used a case study approach to explore the potential of farm-to-school programs to simultaneously improve children's diets and provide farmers with viable market opportunities. Design: Semistructured interviews were the primary data collection strategy. Setting: Seven farm-to-school programs in the Upper Midwest and Northeast regions of the United States. Participants: Seven school food service professionals, 7 farmers, and 4 food distributors recruited from 7 farm-to-school programs. Phenomenon of Interest: Interviews probed why farmers, school food service professionals, and food distributors participate in farm-to-school programs and how they characterize the opportunities and challenges to local school food procurement. Analysis: Data were analyzed using thematic coding and data displays. Results: School food service professionals described 3 motivators for buying locally grown food for their cafeterias: (1) "The students like it," (2) "The price is right," and (3) "We're helping our local farmer." Students' preference for locally grown food was related to food quality, influence of school staff, and relationships with farmers. Buying food directly from farmers and wholesalers was associated with lower prices and flexible specifications, and the "local feel.". Conclusions and Implications: Understanding school food service professionals' motivations for buying locally grown food is critical to the sustainability of farm-to-school programs. © 2010 Society for Nutrition Education.
Howard P.H.,Agriculture |
Allen P.,University of California at Santa Cruz
Rural Sociology | Year: 2010
The success of alternative food initiatives indicates increasing interest in changing the way food is produced, processed, and sold. Ecolabels such as organic and Fair Trade have entered the mainstream marketplace, and other voluntary identifiers on products are emerging to address criteria not included in these successful initiatives. Little is known about consumer interests in these criteria, however. To anticipate the direction of food-system changes, as well as assist food producers to meet consumer demands, we conducted a national mail survey to assess preferences for criteria that go "beyond" (or could complement) organic and Fair Trade. We utilized a forced-choice paired-comparisons question format to rank five possibilities (humane, local, living wage, small-scale, U.S. grown) that might feasibly be implemented by food producers. Local was the most popular choice, although humane also received a high level of support. Multilevel logistic regression indicated that local was preferred by rural residents, and that humane was preferred by frequent organic consumers and high-income households. Survey respondents also chose product labels more frequently than other potential sources of information about their food. Preferences for local and humane ecolabel criteria should be placed in perspective, as consumers expressed much higher levels of interest in the more individualized concerns of safety and nutrition. The results suggest, however, that consumers are interested in a food system that addresses broader political and ethical values, which has implications for production, marketing, and movement building for sustainable food systems. © 2010, by the Rural Sociological Society.
Rogers M.E.,Agriculture |
Lawson A.R.,Agriculture |
Crop and Pasture Science | Year: 2016
Lucerne (Medicago sativa L.) has the potential to be grown widely under water-limiting conditions in the dairy region of northern Victoria and southern New South Wales, Australia, possibly because of its greater water productivity and because irrigation management of lucerne can be more flexible compared with other forage species. A large-scale field experiment was conducted at Tatura in northern Victoria, over 5 years to determine the effects of limiting (deficit) and non-limiting irrigation management on the dry matter (DM) production, water productivity (irrigation and total water productivity) and stand density (or persistence) of lucerne. Nine irrigation treatments were imposed that included full irrigation, partial irrigation and no irrigation in either a single, or over consecutive, irrigation seasons. In the fifth year of the experiment, all plots received the full irrigation treatment to examine plant recovery from the previous irrigation treatments. In any one year, there was a linear relationship between DM production and total water supply (irrigation plus rainfall plus changes in soil water) such that DM production decreased as the total water supply - due to deficit irrigation - decreased. Over the 5 years, annual DM production ranged from 1.4 to 17.7t DM ha-1 with the highest production occurring in plots that received full irrigation. Irrigation water productivity was inversely related to the amount of water used and was higher in the treatments that had only been partially irrigated for that year compared with the treatments that had been fully watered for that year. Total water productivity values were significantly lower only in the treatments that had not been irrigated for that year, and there was little difference between the treatments that were only partially watered during the year and the fully watered treatments (range 9.1-12.2 kg DM ha-1 mm-1 for Year 4). There was no significant reduction in plant density or plant persistence in those plots where deficit irrigation had been imposed. However, the high irrigation regime and poor drainage in the fully irrigated border-check plots significantly reduced plant density and allowed weed infestation in the fifth year of the experiment. These results suggest that, although lucerne DM production is directly related to total water use and may be significantly reduced in the irrigation regions of south-eastern Australia in seasons when water is restricted, the lucerne stand is able to fully recover once a full irrigation regime is resumed. This makes lucerne an ideal forage species for situations when water is limiting. © 2016 CSIRO.