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11.
Leaf anatomical changes were appraised in exogenously applied trehalose of radish (Raphanus sativus L.) plants grown under nonstress (well-watered) and water stress (60% field capacity) conditions. Two cultivars of radish namely, Manu and 40-Day, were grown in a pot experiment at the Botanical Garden, GCUF, Pakistan. Plants were subjected to 60% field capacity conditions after three weeks of germination. Trehalose (25 mM) was applied to the radish plants through two different modes (foliar and presowing). After 2 weeks of foliar-applied trehalose, the leaves were excised from the plants for studying different anatomical features. Water stress caused a significant reduction in the leaf vascular bundle area, leaf midrib thickness (only in cv. Manu), leaf parenchyma cell area, and the number of vascular bundles in both radish cultivars, while water stress increased leaf epidermis thickness of both radish cultivars. Exogenously applied trehalose through both (presoaking and foliar spray) modes was effective in increasing leaf epidermis thickness, vascular bundle area, midrib thickness, and number of vascular bundles in both radish cultivars under water stress and nonstress conditions. Foliar-applied trehalose was more effective in increasing midrib thickness in both radish cultivars under both water regimes. Of both cultivars, the performance of cv. Manu was better in leaf epidermis thickness, leaf midrib thickness, vascular bundle area, leaf parenchyma cell area, and the number of vascular bundles. Overall, exogenous application of trehalose through both modes was effective in triggering leaf anatomical changes under different water regimes.  相似文献   
12.
We undertook a comparative analysis of (peri-)urban livestock production strategies across three West African cities. Using a semi-structured questionnaire, livestock-keeping households (HH) were interviewed in Kano/Nigeria (84 HH), Bobo Dioulasso/Burkina Faso (63 HH) and Sikasso/Mali (63 HH). Questions covered livestock species kept, herd sizes and structure, feeds used, manure management, livestock marketing and production constraints. Sheep and goats dominated (p??0.05), but the proportion of HH heads with a long-term experience in UPA activities was higher in Kano and in Bobo Dioulasso than in Sikasso (p?相似文献   
13.
【目的】研究种源、产地和环境因子对尖果沙枣、沙枣和东方沙枣的产胶率和胶多糖含量的影响。【方法】对新疆不同居群药用资源沙枣实地考察,收集沙枣胶,测算产胶率,提取沙枣胶中多糖并计算含量。【结果】不同基源的沙枣其产胶率和多糖含量统计上无显著差异(P>0.05,P=0.173);产地与产胶率相关性显著(尖果沙枣P=0.003、东方沙枣P=0.019、沙枣P=0.011),即低纬度地区产胶率高于高纬度地区,而产地与胶多糖含量差异不显著(P=0.051);生态因子海拔、无霜期、年均温和年积温与产胶率相关性显著,即海拔越低,无霜期越长,年均温和年积温越高,产胶率越高(P<0.05),而多糖含量与生态因子无显著相关(P值均>0.05)。【结论】在海拔较低的平原和天山以东、以南地区种植沙枣以推广沙枣胶产业。  相似文献   
14.
Objectives: It was aimed to investigate the effects of different doses of follicle stimulating hormone (FSH) and activin A on the growth and maturation of preantral mouse follicles during the in vitro culture. Methods: Preantral follicles (90-100 mum in diameter) were harvested from 6-8 week-old Syrian mice and cultured in TCM199 culture medium for 6 days to see the effect of FSH and Activin A. Activin A concentrations in the range of 10-200 ng/ml were used, while 10, 50, 100, 150 and 200 mIU/ml FSH were used in the experiment. Results: Activin A concentration of 100 ng/ml resulted in a significant increase in follicle diameter (170 mum) with the survival rate of 73% as compared to the control (100 mum and 25%, P<0.05). The number of oocytes matured and the percentage of germinal vesicle breakdown (GVBD) was 61 and 70%, respectively as compared to the control (20 and 29%, P<0.05). Follicle diameter (190 mum) and survival rate (85%) increased significantly in the presence of 100 mIU/ml of FSH as compared to the control (P<0.05). But, the administration of activin A+FSH increased the effect of both factors on follicular diameter (205 mum as compared to 100 mum in control, P<0.01). Follicle survival, oocyte maturation and GVBD rates were 91, 81 and 89%, respectively (P<0.01). Conclusion: These results have suggested that exposure to FSH and activin A before the formation of antral cavity had positive effect on follicle survival and oocyte robustness.  相似文献   
15.

Purpose

Cohesive sediment is able to flocculate and create flocs, which are larger than individual particles and less dense. The phenomenon of flocculation has an important role in sediment transport processes such as settling, deposition and erosion. In this study, laboratory experiments were performed to investigate the effect of key hydrodynamic parameters such as suspended sediment concentration and salinity on floc size and settling velocity. Results were compared with previous laboratory and field studies at different estuaries.

Materials and methods

Experimental tests were conducted in a 1-L glass beaker of 11-cm diameter using suspended sediment samples from the Severn Estuary. A particle image velocimetry system and image processing routine were used to measure the floc size distribution and settling velocity.

Results and discussion

The settling velocity was found to range from 0.2 to 1.2 mm s?1. Settling velocity changed in the case of increasing suspended sediment concentration and was controlled by the salinity. The faster settling velocity occurred when sediment concentration is higher or the salinity is lower than 2.5. On the other hand, at salinities higher than 20, in addition to increasing SSC, it was found that the situation was reversed, i.e. the lower the sediment concentration, the faster the settling velocity.

Conclusions

Sediment flocculation is enhanced with increasing sediment concentration but not with increasing salinity.
  相似文献   
16.
17.
Irrigated trials were conducted during the dry seasons of 2004, 2005 and 2006 at the Irrigation Research Station of the Institute for Agricultural Research (IAR), Nigeria, to study the performance of three groundnut (Arachis hypogaea L.) varieties as affected by basin size and plant population. Treatments consisting of three basin sizes (3 × 3, 3 × 4 and 3 × 5 m), three plant populations (50,000, 100,000 and 200,000 plants ha?1) and three varieties (Samnut 11, Samnut 21 and Samnut 23), were laid out in a split-plot design with factorial combination of population and variety assigned to the main plots and basin sizes to the subplots. Plant height exhibited the highest positive (p ≤ 0.05) effect of 0.3993, 0.5124, 0.6296 and 0.5897, followed by total dry matter (0.2339, 0.3329, 0.4040 and 0.4197) and number of branches (0.1118, 0.0181, 0.0416 and 0.1541) in the three years and when combined. Path coefficient analysis revealed that among the growth characters selected, plant height made the highest positive contribution of 34.77% to pod yield of groundnut, followed by total dry matter with a positive contribution of 17.46%, suggesting plant height was the most critical growth parameter for determining yield of groundnut under irrigation.  相似文献   
18.
High germination percentage with vigorous early growth is preferred for harvesting good wheat stand under saline soils. Therefore, an attempt for rapid screening of wheat genotypes for salt tolerance was made in this study. Eleven wheat genotypes including salt tolerant check Kiran-95were subjected to salinity (120 and 160 mMNaCl) along with non-saline control. Results showed a gradual decrease in seed germination and restricted seedling growth in tested wheat genotypes in response to increasing NaCl concentration in nutrient solution. Among the genotypes, NIA-AS-14-6 and NIA-AS-14-7 exhibited more sensitivity towards the salt stress at the germination stage but NIA-AS-14-6 performed quite satisfactorily later on at the seedling stage. Wheat genotypes NIA-AS-14-2, NIA-AS-14-4, NIA-AS-14-5, NIA-AS-14-10, and Kiran-95 showed better performance in term of root-shoot length, plant biomasses (fresh and dry), K+:Na+ ratio with least Na+ content, and high accumulation of K+ at higher levels of NaCl stress. On the basis of overall results, the categorization of genotypes was carried out as sensitive, moderately tolerant, and tolerant. Wheat genotypes NIA-AS-14-2, NIA-AS-14-4, NIA-AS-14-5, NIA-AS-14-10, and Kiran-95 grouped as tolerant, moderately salt tolerant group comprised of NIA-AS-14-1, NIA-AS-14-3, NIA-AS-14-6, and NIA-AS-14-8, whereas, NIA-AS-14-7 and NIA-AS-14-9 were found sensitive to salt stress. Principal component analysis revealed that components I and II contributed 70 and 16.5%, respectively. All growth parameters are associated with each other except RDW. In addition to growth traits, low Na+ and improved K+ content with better K+:Na+ ratio may be used for screening of salt tolerance in wheat as potential physiological criteria.  相似文献   
19.
Distal ulnar ostectomy may be performed palliatively in patients with distal ulnar osteosarcoma. Concurrent arthrodesis of the carpus has been proposed to counteract joint instability following transection of carpal ligaments associated with removal of the distal ulna. The objective of this prospective one group pretest, posttest study was to assess stability of the carpus following distal ulnar ostectomy using pre‐ and postoperative stress radiographic views in a group of canine cadaver limbs. Seven thoracic limbs from six canine cadavers weighing more than 20 kg were obtained. Lateral and dorsopalmar, extended lateral, medial stress, and lateral stress radiographs were made before and after distal ulnar ostectomy. Presurgical canine cadaver carpal angle measurements were as follows (mean ± standard deviation): extension 205.9° ± 5.4; medial stress 25.1° ± 5.7; and lateral stress 13.3° ± 5.2°. Cadaver limb joint angles exceeded those previously reported in live dogs. A significant increase in carpal angle was noted following ulnar ostectomy. The mean increases in carpal angle were as follows: (mean ± standard deviation (95% confidence interval)): extension 6.2° ± 4.9 (2.6–9.8) (P = 0.007); medial stress 3.2° ± 3.0 (1.0–5.5) (P = 0.015); lateral stress 6.2° ± 5.2 (2.4–10.1) (P = 0.010). Findings from this cadaver study support the use of supplementary stabilization for clinical patients undergoing distal ulnar ostectomy. Future studies are needed in clinical patients to evaluate changes in limb positioning and gait associated with distal ulnar ostectomy.  相似文献   
20.
Impact of tannic acid (TA), date seed extract (DSE), catechin (CT) and green tea extract (GTE) on lipid oxidation, microbial load and textural properties of camel meat sausages during 12 days of refrigerated storage was investigated. TA and CT showed higher activities in all antioxidative assays compared to DSE and GTE. Lipid oxidation and microbial growth was higher for control sausages when compared to other samples. TA and CT at a level of 200 mg/kg were more effective in retarding lipid oxidation and lowering microbial count (P < 0.05). Sausages treated with TA and DSE were found to have higher hardness, gumminess and chewiness values compared to other treatments (P < 0.05). Addition of different phenolic compounds or extract did not influence the sensory color of sausages. Furthermore, sensory quality was also found to be superior in TA and CT treated sausages. Therefore, pure phenolic compounds (TA and CT) proved to be more effective in retaining microbial and sensorial qualities of camel meat sausages compared to phenolic extracts (GTE and DSE) over 12 days of storage at 4°C.  相似文献   
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