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91.

Context   

Turkish red pine (Pinus brutia Ten.) is widespread in the eastern Mediterranean Basin. In the late 1970s, four common gardens were established along steep altitudinal transects extending from the coast to about 1,200 m in the Taurus Mountains (Antalya, Turkey).  相似文献   
92.
93.
Mycorrhizae can enhance plant growth and phosphorus (P) use efficiency in horticultural plants. This research evaluated the effectiveness of mycorrhizae on increasing growth and yield of nine horticultural plants for two different rates of P fertilization under field conditions. The mycorrhizal inoculums increased the root colonization of mycorrhizal horticultural plants compared with the non-inoculated treatments. Mycorrhizal inoculation significantly increased onion, garlic, chickpea, broad bean, carrot, parsley and cress plants. Mycorrhizal effectiveness showed that without P addition the effect of mycorrhizae on plant yield is much higher than that with P fertilizer addition. Under low P fertilization inoculation effectiveness is much higher than P addition treatments. Mycorrhizal inoculums also increased tissue P and zinc (Zn) for horticultural plant. The improved growth, yield, Zn and P uptake in plants demonstrated the potential of mycorrhizal inoculation to reduce the effects P fertilization on horticultural plants grown under field conditions.  相似文献   
94.
Seven dogs with parasitologically proven clinical visceral leishmaniosis (Leishmania infantum infection) were treated with a combination of allopurinol and sodium stibogluconate. The dogs received first orally 15 mg/kg of allopurinol every 12 h until the clinical signs improved, in the following 1 month period allopurinol at same dose and subcutaneously 30 mg/kg of sodium stibogluconate combination were given daily and at the end of the combined treatment, allopurinol was continued alone at the same dose till the end of 8 months. During the treatment period, dogs were supported by additional proteins, vitamins, and minerals. A long acting insecticide (collar or drop) was also used in order to prevent further parasite transmission. Follow-up was maintained by clinical, clinicopathological evaluation, and parasitological examination of lymph node, serology using the indirect immunofluorescent antibody test (IFAT). Before treatment commenced, the most important clinical signs were exfoliative dermatitis, ulcerations, peripheral lymhadenopathy, pale mucous membranes, weight loss, and ocular lesions. Clinicopathological findings included commonly anaemia, hyperproteinaemia, hyperglobulinaemia and hypoalbuminaemia. Before the treatment, amastigotes were seen in six of the seven dogs by examination of lymph node aspiration, and IFAT-titers were positive in all dogs. At the end of 8 months treatment, remission of clinical signs, restoration to normal of clinicopathological abnormalities were noticed. Lymph node aspiration was performed on three out of the seven dogs at the end of the treatment because of the very small sizes of the lymph nodes, and no amastigotes were observed. Although the mean IFAT-titer of the dogs were significantly (P < 0.001) lower compared with pretreatment, IFAT-titers of dogs were still positive. No relapses occurred during treatment period and a 6-24-month duration after the end of therapy. Based on the above results, long-term use of allopurinol combined with sodium stibogluconate together with support treatment concluded to have enough therapeutic efficacies in the treatment of dogs with visceral leishmaniosis. Observations of the cases for possible relapses were still going on and insecticide application was carefully carrying on in order preventing a possible re-infection.  相似文献   
95.
This study was conducted in 2007–2008 to determine the effects of different irrigation regimes on yield, quality and water-yield relationships of young dwarf ‘Gala, Galaxy’ apple trees in Isparta-Turkey. Irrigation water was applied based on a ratio of class A pan evaporation (rates of 0.0 (kcp0), 0.25 (kcp1), 0.50 (kcp2), 0.75 c (kcp3), 1.00 (kcp4) and 1.25 (kcp5)) with 5-day intervals. The effects of irrigation regimes on yield and fruit weight were statistically significant. Seasonal evapotranspiration was measured as 246.5–608.2 mm and 289.3–631.9 mm in 2007 and 2008, respectively. Water use efficiency lead to a yield ranging from 0.0023 to 0.0055 t ha?1mm?1 and from 0.0033 to 0.0111 t ha?1mm?1 and irrigation water use efficiency varies from 0.0009 to 0.0073 t ha?1mm?1 and from 0.0045 to 0.0186 t ha?1mm?1 in 2007 and 2008, respectively. The annual average yield response factor, ky, was 1.22. As a result of the research, it was concluded that the irrigation schedule for the 0.75 kcp3 treatment, applying 0.75 of evaporation from class A pan, could be used in the irrigation of young dwarf apple trees without evident reduction in yield and that high water use efficiencies could be obtained.  相似文献   
96.
The effects of etoxazole were evaluated in freshwater fish Oreochromis niloticus from five different sublethal etoxazole concentrations in order to study the biochemical response, photometrically. No changes were observed in the activities of antioxidant enzymes such as superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), and glutathione peroxidase (GPx, EC 1.11.1.9). These were measured in liver after 1, 7, and 15 days of exposure to sublethal concentrations of 0.2, 0.4, 0.6, 0.8, and 1% of field application rate (134.75 ppm). This study also investigated the levels of neurotoxic effects by the determination of acetylcholine esterase (AChE EC 3.1.1.7) and sodium-potassium adenosine 5-triphosphatase (Na+K+-ATPase, EC 3.6.3.9) activities. The exposure of fish led to sharp depletion in AChE activity while there is no significant alteration in Na+K+-ATPase activity. Up to 80% decreases were observed in the AChE activity. Since no difference was found in the activity of glutamate-pyruvate transaminase (GPT, EC 2.6.1.2), etoxazole did not show hepatotoxic effect. The results of the present study show that increase in the malondialdehyde (MDA) contents and decrease in the AChE activity can be used as biomarkers for monitoring toxicity in etoxazole exposure.  相似文献   
97.
尼日利亚北方大果型芒果施肥方案的研究   总被引:1,自引:0,他引:1  
为了迅速提高其生态类型类似非洲、尼日利亚、包奇市区域的芒果生产水平,笔者设计进行L9(3)4+1的正交试验。经过试验初步明确了投肥方式以7月上中旬和9月中下旬2次投肥的方式,有显著的提高肥效和增产的效应。在投肥中7月上中旬以氮钾为主,9月中下旬氮、磷、钾配合为佳。投肥中应加重氮肥和钾肥的投入,并且适度加大投肥量,其增产和提高经济效益的效果明显,并为进一步深入研究当地的最佳投肥方案提供参考。  相似文献   
98.
To improve the functional properties of cast kafirin films, dry kafirin, extracted with an aqueous ethanol‐based solvent at 70°C, was microwave‐heated. No effect on film tensile properties was found. Two strategies were employed to improve the effect of microwaving: extraction of kafirin using an aqueous tert‐butanol‐based solvent at ambient temperature to minimize temperature‐induced denaturation and wetting the kafirin to increase its dielectric properties. Microwave heating this kafirin to 90 or 96°C and holding for 1–2 min more than doubled maximum tensile strength and Young's modulus, and decreased strain by about one‐third compared with films made from nonmicrowaved kafirin. Film water vapor permeability was reduced by at least one‐third. Digestibility of microwaved kafirin and films was also substantially decreased, and film biodegradability was slowed slightly. Microwave heating gave a film microstructure with fewer and smaller size pores. SDS‐PAGE showed microwave‐induced intermolecular cross‐linking of the kafirin monomers, which was possibly responsible for the modification of film properties. Microwave heating of kafirin can be used to modify kafirin film properties, but the kafirin must be microwaved wet and be as close as possible to its native state.  相似文献   
99.
Determination of temporal and spatial distribution of water use (WU) within agricultural land is critical for irrigation management and could be achieved by remotely sensed data. The aim of this study was to estimate WU of dwarf green beans under excessive and limited irrigation water application conditions through indicators based on remotely sensed data. For this purpose, field experiments were conducted comprising of six different irrigation water levels. Soil water content, climatic parameters, canopy temperature and spectral reflectance were all monitored. Reference evapotranspiration (ET0), crop coefficient Kc and potential crop evapotraspiration (ETc) were calculated by means of methods described in FAO-56. In addition, WU values were determined by using soil water balance residual and various indexes were calculated. Water use fraction (WUF), which represents both excessive and limited irrigation applications, was defined through WU, ET0 and Kc. Based on the relationships between WUF and remotely sensed indexes, WU of each irrigation treatments were then estimated. According to comparisons between estimated and measured WU, in general crop water stress index (CWSI) can be offered for monitoring of irrigated land. At the same time, under water stress, correlation between measured WU and estimated WU based on CWSI was the highest too. However, canopy-air temperature difference (Tc − Ta) is more reliable than others for excessive water use conditions. Where there is no data related to canopy temperature, some of spectral vegetation indexes could be preferable in the estimation of WU.  相似文献   
100.
以渭干河-库车河三角洲绿洲连作5、10、15、20 a和25 a的棉田土壤为研究对象,对棉田土壤的理化性质和酶活性进行分析。结果表明: 随着棉花连作年限的增长棉田土壤容重增大、孔隙度下降,粗砂和细沙含量增加,粘粒含 量下降,其变化连作15 a极为明显; 随着连作年限的增长盐分含量和pH值逐渐降低,有机质和碱解氮含量大幅度升高,速效磷比较稳定或略有减小,而钾的含量显著下降,致使氮、磷、钾比例失调,其增减变化连作15 a极为显著; 随着连作年限的增长脲酶、过氧化氢酶和转化酶的活性呈现先升后降的趋势,连作15 a都达到最高值,蛋白酶和磷酸酶活性也呈现先升后降的趋势,但其活性连作20 a达到最高值。 由研究结果可以得出研究区棉花连作年限不宜超过15 a,棉花连作年限超过15 a时,会导致土壤容重增大、孔隙度下降,土体紧实板结,结构性差,土壤养分含量失衡,酶活性降低,土壤质量下降等连作障碍,使得棉花产出和效益受到影响。  相似文献   
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