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1.
Mohammad FK Alias AS Faris GA Al-Baggou BKh 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(3):140-143
A modified electrometric cholinesterase method has been described for use in ruminants exposed to organophosphate insecticides. The method was used to measure cholinesterase activities in the plasma and erythrocytes of sheep, goats and cattle treated with organophosphate insecticides under field conditions. The animals were treated topically to control ectoparasites with malathion (0.05%) or diazinon (0.06%). The treated animals did not suffer from adverse effects related to cholinesterase inhibition. However, 2 h after treatments, plasma and erythrocyte cholinesterase activities significantly decreased in sheep by 20% and 39% and in goats by 18% and 30%, respectively, when compared with respective untreated control values. Diazinon did not significantly affect plasma and erythrocyte cholinesterase activities in the cattle. The results suggest that the described electrometric method could be efficiently used for detecting cholinesterase inhibition in ruminants exposed to organophosphate insecticides. 相似文献
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3.
A 2-year field study was conducted to determine the effects of different nutrition systems and Salsola kali subsp. tragus densities on industrial hemp yield and its components. Experiments were conducted as a split plot in a randomised complete block design with three replicates. Factors were fertilisation (poultry manure, vermicompost and nitrogen fertiliser) as the main plot and weed density (0, 5, 10, 15 and 20 plants/m2) as the subplot. Results indicated that the maximum number of racemes per plant, seeds per raceme, 1000-seed weight, biomass, grain yield and harvest index (HI) of industrial hemp were obtained using vermicompost and were reduced with nitrogen fertiliser application. All measured properties in hemp plants decreased due to increasing S. kali subsp. tragus density, especially at 15 and 20 plants/m2. The most significant reduction in hemp grain yield and its components was observed by increasing weed density with the application of nitrogen fertiliser. The application of vermicompost at high weed densities resulted in greater hemp grain yield and its components compared with nitrogen fertiliser. It is recommended to apply organic fertilisers, especially vermicompost at high S. kali subsp. tragus densities. 相似文献
4.
Bayzid Yousefi Seyed Reza Tabaei-Aghdaei Farrokh Darvish Mohammad Hassan Assareh 《Scientia Horticulturae》2009
The flower yield stability of Damask rose as an important medicinal and aromatic plant at different environments has not been well documented. In order to evaluate flower yield and stability, 35 landraces of Damask rose were studied at 8 locations in Iran during 2007–2008. Analysis of variance revealed significant differences (p ≤ 0.01) among landraces (G), environments (E), locations (L) and for landrace × environment (GE) and landrace × location (GL) interactions. Both GE and GL interactions were mainly crossover, a large portion of which was accounted for by non-linear (unpredictable) component. The landraces of IS9, YZ2, WA1, IS7 and IS1 with 3120.63, 2941.63, 2894.62, 2769.15 and 2716.92 kg/ha respectively produced the highest flower yield among studied landraces. Kerman with average flower yield of 3635.46 kg/ha produced the highest yield among studied locations. According to the results, most of landraces that originated from temperate, warm temperate and arid regions produced higher flower yield than those from cool, cool temperate, semi-arid and humid regions. The landraces of YZ2, IS5, IS8, IS4, KZ1, AR1, IS3 and BA1 were stable and YZ2, IS5, IS8, IS4, KZ1, AR1 IS6, IS3, BA1, IS10 and YZ1 were adaptable landraces for flower yield according to Eberhart and Russell (1966) model. The presence of some high flower yield and stable landraces such as YZ2 and IS5 suggests that a genotype can demonstrate high flower yield and stability for yield simultaneously. Thus, simultaneous selection for flower yield and stability using nonparametric methods could be possible. In addition, taking into consideration flower yield and stability potential, the landraces of YZ2, IS5, IS8, IS4 and KZ1 as general stable, adaptable, and high flower yield are recommended. Furthermore, the landraces of IS9 and WA1 as high flower yield and specific adaptable landraces can be recommended for temperate and arid areas and the landraces of IS7 and IS1 for semitemperate and cool areas. 相似文献
5.
Saeedeh Rafatnezhad Bahram Falahatkar Mohammad H Tolouei Gilani 《Aquaculture Research》2008,39(14):1506-1513
The influence of stocking density (1, 2, 4, 6 and 8 kg m?2) was investigated on haematological parameters, growth and fin erosion of great sturgeon (Huso huso) juveniles for a period of 8 weeks. The mean weight of fish at the start of trial was 93.13±1.04 g. After 8 weeks of rearing, the mean weight was 362.4, 319.7, 267, 242.1 and 211.1 in densities 1–8 kg m?2 respectively. The results of this study showed that growth parameters, including condition factor, weight, weight gain, feed conversion ratio, specific growth rate and body weight increase, had a statistically significant difference among treatments (P<0.05). A significant difference (P<0.05) was observed in haematocrit, but the other haematological parameters, including red blood cells, white blood cells (WBC), haemoglobin concentration, mean corpuscular haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin concentration and differential WBC count, showed no significant effect with stocking density (P>0.05). At the end of the experiment, stocking density had no significant effect on plasma cortisol and glucose concentration. The fin length (dorsal, anal, ventral, pectoral and caudal) of fish was measured to calculate the fin index. According to this index, dorsal, anal, ventral and pectoral fins showed no significant difference among treatments (P>0.05), but the erosion of the caudal fin was significantly different between fish held on 6 and 8 kg m?2 (P<0.05). These results showed that rearing density has a major effect on the growth indices of H. huso. Unlike many other fish, great sturgeon exhibited lower stress responses to high stocking density. This indicates that they are more tolerable to rearing conditions in high stocking densities. With respect to the various effects that density causes on growth, fin erosion and physiological and haematological parameters, better understanding of these phenomena considering different levels of density could have a beneficial impact on many rearing steps of this species. 相似文献
6.
Abdus Sattar Mohammad Wahid Shahid Khan Durrani 《Plant foods for human nutrition (Dordrecht, Netherlands)》1989,39(3):279-286
Different spices, dry fruits and plant nuts commonly consumed in Pakistan were assayed for the heavy metals cadmium, lead, copper, zinc, iron and manganese by the potentiometric stripping analysis and AA spectrophotometry. The results revealed wide variation in heavy metal content among different biological materials. Mixed spices generally exhibited higher value for trace metals specially lead (6.6–9.2 µg/g), cadmium (0.65–1.34 µg/g), iron (142.3–285.0 µg/g) and zinc (64.2–65.8 µg/g). Dry fruits contained relatively lesser amounts of heavy metals than plant nuts. Almonds contained higher levels of lead (1.02 µg/g) and cadmium (0.24 µg/g) than other nuts and dry fruits. 相似文献
7.
The Penman–Monteith (FAO-56 PM) equation is suggested as the standard method for estimating evapotranspiration (ET0) by the International Irrigation and Drainage Committee and Food and Agriculture Organization (FAO). On the other hand, the Hargreaves–Samani (HS) equation is an alternative method compared with the FAO-56 PM equation. In the present study, the original coefficient C of the HS equation is calibrated based on the FAO-56 PM equation for estimating the reference ET0 from 15 meteorological stations in central Iran (about 170,000 km2) under semiarid and arid conditions. After calibration, the new values for C are ranged from 0.0018 to 0.0037. The mean bias error (MBE), the root mean square error (RMSE), and the ratio of average estimations of ET0 (R) values for all stations are ranged from 0.12 to 5.38, ?5.35 to 1.15 mm d?1 and 0.64 to 1.28 for the HS equation and from 0.12 to 2.48, ?2.2 to 0.60 mm d?1, and 1.00 to 1.05 for the calibrated Hargreaves–Samani equation (CHS), respectively. Results indicate that the average RMSE and MBE values are decreased by 40% and 66%, respectively. Relationships for calibrating the C coefficient on the basis of annual average of daily temperature range (ΔT) and wind speed (V) are proposed, calibrated, and validated. Hence, the CHS equation can be used for ET0 estimates with acceptable accuracy instead of the FAO-56 PM method. 相似文献
8.
Rahul Tripathi A. K. Nayak R. Raja Mohammad Shahid S. Mohanty B. Lal 《Communications in Soil Science and Plant Analysis》2017,48(10):1154-1166
Proper doses of nitrogenous fertilizer are most important for rice production system because a large part of the nitrogen may be lost if it is not applied judiciously. A study was conducted covering five blocks of Balasore and two blocks of Bhadrak districts. Soil samples were collected randomly, and field visit was conducted during peak vegetative stage of rice. Two approaches have been used in this study for estimating the site-specific nitrogen (N) requirement in the study area. In one approach, geostatisical analysis and kriging was used to develop the soil test–based N recommendation map by which a minimum of 72 kg N ha?1 and maximum of 94 kg N ha?1 were recommended. In a second approach, remote sensing was used and N recommendation map was developed using the moderate-resolution imaging spectroradiometer (MODIS) leaf area index (LAI) and normalized difference vegetation index (NDVI) satellite data, and a minimum requirement of 60 kg N ha?1 and maximum of 120 kg N ha?1 was estimated through this approach. 相似文献
9.
Tomislav Hengl Norair Toomanian Hannes I. Reuter Mohammad J. Malakouti 《Geoderma》2007,140(4):417-427
The paper compares semi-automated interpolation methods to produce soil-class maps from profile observations and by using multiple auxiliary predictors such as terrain parameters, remote sensing indices and similar. The Soil Profile Database of Iran, consisting of 4250 profiles, was used to test different soil-class interpolators. The target variables were soil texture classes and World Reference Base soil groups. The predictors were 6 terrain parameters, 11 MODIS EVI images and 17 physiographic regions (polygon map) of Iran. Four techniques were considered: (a) supervised classification using maximum likelihoods; (b) multinominal logistic regression; (c) regression-kriging on memberships; and (d) classification of taxonomic distances. The predictive capabilities were assessed using a control subset of 30% profiles and the kappa statistics as criterion. Supervised classification and multinominal logistic regression can lead to poor results if soil-classes overlap in the feature space, or if the correlation between the soil-classes and predictors is low. The two other methods have better predictive capabilities, although both are computationally more demanding. For both mapping of texture classes and soil types, the best prediction was achieved using regression-kriging of indicators/memberships (κ = 45%, κ = 54%). In all cases kappa was smaller than 60%, which can be explained by the preferential sampling plan, the poor definition of soil-classes and the high variability of soils. Steps to improve interpolation of soil-class data, by taking into account the fuzziness of classes directly on the field are further discussed. 相似文献
10.
Mohammad I. Khalil Muhammad S. Rahman Urs Schmidhalter Hans‐Werner Olfs 《植物养料与土壤学杂志》2007,170(2):210-218
A 90‐day laboratory incubation study was carried out using six contrasting subtropical soils (calcareous, peat, saline, noncalcareous, terrace, and acid sulfate) from Bangladesh. A control treatment without nitrogen (N) application was compared with treatments where urea, ammonium sulfate (AS), and ammonium nitrate (AN) were applied at a rate of 100 mg N (kg soil)–1. To study the effect of N fertilizers on soil carbon (C) turnover, the CO2‐C flux was determined at nine sampling dates during the incubation, and the total loss of soil carbon (TC) was calculated. Nitrogen turnover was characterized by measuring net nitrogen mineralization (NNM) and net nitrification (NN). Simple and stepwise multiple regressions were calculated between CO2‐C flux, TC, NNM, and NN on the one hand and selected soil properties (organic C, total N, C : N ratio, CEC, pH, clay and sand content) on the other hand. In general, CO2‐C fluxes were clearly higher during the first 2 weeks of the incubation compared to the later phases. Soils with high pH and/or indigenous C displayed the highest CO2‐C flux. However, soils having low C levels (i.e., calcareous and terrace soils) displayed a large relative TC loss (up to 22.3%) and the added N–induced TC loss from these soils reached a maximum of 10.6%. Loss of TC differed depending on the N treatments (urea > AS > AN >> control). Significantly higher NNM was found in the acidic soils (terrace and acid sulfate). On average, NNM after urea application was higher than for AS and AN (80.3 vs. 71.9 and 70.9 N (kg soil)–1, respectively). However, specific interactions between N‐fertilizer form and soil type have to be taken into consideration. High pH soils displayed larger NN (75.9–98.1 mg N (kg soil)–1) than low pH soils. Averaged over the six soils, NN after application of urea and AS (83.3 and 82.2 mg N (kg soil)–1, respectively) was significantly higher than after application of AN (60.6 mg N (kg soil)–1). Significant relationships were found between total CO2 flux and certain soil properties (organic C, total N, CEC, clay and sand content). The most important soil property for NNM as well as NN was soil pH, showing a correlation coefficient of –0.33** and 0.45***, respectively. The results indicate that application of urea to acidic soils and AS to high‐pH soils could be an effective measure to improve the availability of added N for crop uptake. 相似文献