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81.
Cropping system models are widely used tools for simulating the growth and development of crops at field scale. However, it is often difficult to satisfy their detailed input and output data requirements for a proper evaluation of model. In this study, expert knowledge data were used as alternative source to fulfil these data requirements. The model was first calibrated for major crops of the studied area and then evaluated for the same crops by using expert knowledge data. Results showed that the model accurately simulated above-ground biomass and grain yield with a relative root mean square error (RRMSE) of 20% and 17%, respectively. On the other hand, simulated results were less satisfactory for N uptake and cumulated evapotranspiration with RRMSE of 27% and 31%, respectively. The model simulated cumulative variables more accurately than dynamic variables. The results of this study suggest that expert knowledge can be used to get data for intermediate variables rarely measured in experiments used for calibration (green leaf area index, actual evapotranspiration, rooting depth) in typical crop management conditions in the region. This approach enables a global and dynamic evaluation of cropping system models when experimental data is unavailable for large heterogeneous areas in a region.  相似文献   
82.
Monounsaturated fatty acids (MUFA)-rich and n-6 polyunsaturated fatty acid (n-6 PUFA)-rich vegetable oils are increasingly used as fish oil replacers for aquafeed formulation. The present study investigated the fatty acid metabolism in juvenile European sea bass (Dicentrarchus labrax, 38.4 g) fed diets containing fish oil (FO, as the control treatment) or two different vegetable oils (the MUFA-rich canola/rapeseed oil, CO; and the n-6 PUFA-rich cottonseed oil, CSO) tested individually or as a 50/50 blend (CO/CSO). The whole-body fatty acid balance method was used to deduce the apparent in vivo fatty acid metabolism. No effect on growth performance and feed utilization was recorded. However, it should be noted that the fish meal content of the experimental diets was relatively high, and thus the requirement for n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) may have likely been fulfilled even if dietary fish oil was fully replaced by vegetable oils. Overall, relatively little apparent in vivo fatty acid bioconversion was recorded, whilst the apparent in vivo β-oxidation of dietary fatty acid was largely affected by the dietary lipid source, with higher rate of β-oxidation for those fatty acids which were provided in dietary surplus. The deposition of 20:5n-3 and 22:6n-3, as % of the dietary intake, was greatest for the fish fed on the CSO diet. It has been shown that European sea bass seems to be able to efficiently use n-6 PUFA for energy substrate, and this may help in minimizing the β-oxidation of the health benefiting n-3 LC-PUFA and thus increase their deposition into fish tissues.  相似文献   
83.
In this study, removal of Congo red (CR) from aqueous solution by 1,6-diaminohexane-functionalized glycidyl methacrylate-g-poly(ethylene terephthalate) (HMDA-GMA-g-PET) fiber was investigated. A new aminated fibrous adsorbent was prepared by a reaction between amine and epoxy group in GMA-g-PET fiber prepared by grafting GMA monomer onto poly (ethylene terephthalate) (PET) fiber. Effects of various parameters such as pH, treatment time, initial, dye concentration, and reaction temperature on the adsorption amount of dye onto reactive fiber were investigated. The adsorption rates of CR were much higher on the HMDA-GMA-g-PET fiber than on GMA-g-PET and ungrafted PET fiber. The effective pH was 2.0 for adsorption on grafted PET fiber. It was found that the sufficient time to attain equilibrium was 60 min. The maximum adsorption capacity of the reactive fiber for CR is 16.6 mg/g fiber. The rates of adsorption were found to conform to the pseudo-second order kinetics with good correlation. It was found that the adsorption isotherm of CR fitted Freundlich type isotherm.  相似文献   
84.
The scale insects Acanthomytilus sacchari (Hall) and Duplachionaspis erianthi Borchsenius (Hemiptera, Diaspididae) are newly recorded as indigenous insects from Turkey. Both A. sacchari and D. erianthi were found to feed only on rhizomes of Johnsongrass. A field study was conducted to determine host ranges and feeding effects of these scale insects on Johnsongrass, Sorghum halepense (L.) Pers. No feeding of these species was observed on Zea mays L. (maize), Sorghum sudanense Staph. (sorghum), Aegilops triuncialis L. (barbed goatgrass), Avena fatua L. (wild oat), A. sterilis (sterile oat), Bromus tectorum L. (downy brome), Cynodon dactylon (L.) Pers. (bermudagrass), Phragmites australis (Cav.) Trin. ex Steudel (common reed), Poa bulbosa L. (bulbous bluegrass), or Secale montanum Guss. (wild rye). The mean infestation rates of the scale insects on Johnsongrass in southeastern Anatolia were 11.47% and 1.64% for A. sacchari and D. erianthi, respectively. Further investigations are required to clarify their biology and damage to Johnsongrass under field conditions.  相似文献   
85.
Turkey is one of the richest areas in the middle latitudes in terms of plant diversity. It has approximately 12 000 plant species and a great number of new species are being added each year. However, invasive alien species have not yet been fully considered in Turkey and only two plant species are in Turkey's quarantine list (Arceuthobium spp. and Eichhornia crassipes). EPPO is an intergovernmental organization responsible for cooperation in plant protection in the European and Mediterranean region and maintains the A1 and A2 Lists of pests recommended for regulation (A1 species are absent from the EPPO region, A2 species are present but of limited distribution), the List of Invasive Alien Plants, the Observation List of invasive alien plants and the Alert List. Eichhornia crassipes, Heracleum persicum, Heracleum sosnowskyi, Ludwigia peploides, Polygonum perfoliatum and Solanum elaeagnifolium are among the species which were recorded in Turkey and are included in the EPPO A2 List. Species recorded in the EPPO List of invasive alien plants which are present in Turkey are: Acroptilon repens, Ailanthus altissima, Ambrosia artemisiifolia (= A. elatior), Carpobrotus edulis, Cortaderia selloana, Cyperus esculentus, Paspalum distichum (= P. paspalodes), Oxalis pes‐caprae and Sicyos angulatus. Azolla filiculoides and Rhododendron ponticum are listed in the EPPO Observation List of Invasive alien plants and Miscanthus sinensis, listed in the EPPO Alert List, are also recorded in the Turkish flora.  相似文献   
86.
Formalin (37–40% formaldehyde) is one of the most effective, widely used chemical in pisciculture for its antiparasitic, antifungal and prophylactic activities. It is used in paints, cleaning products and textile industry, as well. Genotoxic and histological effects of sublethal formalin exposure on Nile tilapia (Oreochromis niloticus) are investigated in this study. The semi‐static acute test was employed. One‐tenth, one‐fifth and half of the 96‐h LC50 value, 148 mg L?1, were used as sublethal exposure concentrations: 15, 30 and 75 mg L?1 for 24, 48, 96 and 168 h respectively. The micronucleus test was applied to investigate the genotoxic effects on fish erythrocytes at the end of predetermined exposure periods and all tissues of the fish were sampled for histological examination. The micronucleus frequencies increased significantly in all exposure groups when compared with their control groups in a dose and time dependent manner (< 0.05). Results of histological examination showed no histopathological findings in the gonads, heart, skeletal muscle, spleen and intestine tissues after sublethal formalin exposure. Passive hyperaemia of liver tissue in varying proportions, hydropic degeneration, fatty degeneration in high concentrations, branchitis on gill tissues in varying proportions, epithelial lifting, telangiectasia, bleeding in kidney and hyperaemia were found in Nile tilapia exposed to formalin at different concentrations and durations. As a result, it is thought that formalin leads to tissue damage and shows genotoxic effects even at 15 mg L?1 concentration in O. niloticus.  相似文献   
87.
Black carrots (Daucus earota L. spp. sativus. ) were fermented for 4 weeks by using six different starter dough formulations. Some of the samples were pasteurized to detemaine the effects of heat treatment on fermentation. Fermentation was followed by physicochemical and microbiological analysis. Some characteristics such as dry matter, crude fiber, water soluble extract, alcohol soluble extract, ether soluble extract, crude energy, total sugar, pH, salt and colour values and mineral contents of black carrot were determined. In the beginning of the fermentation, dry matter is highest in the brines with coriandrium and dry matter of the other brines are close to each other and lower than that of the brines with coriander. The number of Lactic acid bacteria, total bacteria, moulds-yeasts and coliform bacteria decreased through the end of fermentation. Heat treatment had a considerable effect on microbial growth. The microbial growth was higher in the nnpastenrized samples. Total bacteria number reached the highest level for the pasteurized samples ( 104 cfu/mL - 105 cfu/mL ) and for the unpasteurized samples (106 cfu/mL - 107 cfu/mL) in the second day. After the fermentation, sensory analyses were carried out to determine the storage stability of the last products. While "a" value increased, "b" and "L" values decreased during storage time. Yoghurt inoculated brine were preferred from the colour, odour and acceptability points of view.  相似文献   
88.
Tissue samples were collected at random from cattle (Bos taurus) and buffalo (Bubalus bubalis) from an abattoir of the district of Lahore and were analyzed for the presence of Mycobacterium avium subsp. paratuberculosis and Mycobacterium bovis through acid-fast staining and polymerase chain reaction (PCR). Body condition of animals and diarrhea were recorded. Most of the animals were emaciated. Diarrhea was noticed in 15.6% of buffaloes and 19.2% of cattle. Intestinal pathology was observed in 29% of buffaloes and 32.8% of cattle. Number of mesenteric lymph node (MLN) showing gross lesions was a bit higher (35.6%) in cattle than buffalo (31.2%). Acid-fast staining of tissue scraping smears revealed the presence of acid-fast bacilli (AFB) in 17.4% intestinal and 16.4% MLN tissue samples in buffalo, while in cattle 19.2% intestinal and 17.8% MLN were found positive for AFB. In buffaloes, PCR confirmed 12.8% intestinal and 12.4% MLN positive samples for M. avium subsp. paratuberculosis. However, in cattle, PCR analysis demonstrated 14.2% positive results for M. avium subsp. paratuberculosis in both MLN and intestinal tissue samples. PCR also confirmed M. bovis in 5.8% of cattle and 5% of buffalo MLN and intestinal tissues. PCR positive tissue samples for M. avium subsp. paratuberculosis were from those animals which were emaciated, having diarrhea, and severe gross lesions. AFB were also detected in tissue scraping smears of these animals. It is concluded that infection by various mycobacterium species can be differentiated by PCR, which is not possible by acid-fast staining technique.  相似文献   
89.
Inability to produce large quantities of high quality, relatively diseasefree potato seed is a major constraint to providing economic support to a highly important and rapidly expanding potato production industry in Pakistan. Studies were undertaken for 5 years to evaluate productivity of seed of cultivars Red Bad, Ajax, Atica, Patrones, Montana, Cosima, Desiree, and Cardinal grown at five environmentally diverse locations in Pakistan versus seed of the same cultivars imported from Europe. The productivity trials were conducted during the autumn and spring seasons at the Ayub Agricultural Research Institute, Faisalabad (Punjab Plains). The results from the 5-year test period indicate that seed of each of the cultivars produced in the high hills (Baluchistan, Northwest Frontier Province) and during autumn (September to December) in the Punjab Plains, the latter cold stored until the following September, are equally as productive as seed imported from Europe.  相似文献   
90.
Effect of nickel sulphate at the sublethal dose of 64 ppm (0.8 of LC50 96 hr) on the blood glucose levels of the freshwater fish, Colisa fasciatus, has been estimated from 3 to 96 hr. The blood glucose level exhibits a steady increase due to Ni toxicity. A maximum increase of 85.08% is observed at 96 hr (P < 0.001). It is suggested that the hyperglycemia in C. fasciatus, caused by exposure to nickel sulphate, is possibly a reflection of stress-induced hormone mediated response. It appears that the blood glucose level is a reliable indicator of Ni toxicity to fish.  相似文献   
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