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101.
Amin Nobahar Hamid Reza Zakerin Saeed Sayfzadeh Ali Reza Valadabady 《Communications in Soil Science and Plant Analysis》2019,50(6):749-762
Groundnut is an annual legume and important oilseed crop in the world. In order to evaluate the influence of the topping height and application methods of Zinc (Zn) and Calcium (Ca) nano-chelates on quantitative and qualitative characteristics of groundnut, these experiments were carried out during the 2016–2017 cropping seasons on groundnut in Iran. Both foliar and in soil applications of Zn and Ca nano-chelates improved groundnut yield. Foliar application of Zn nano-chelate in combination with topping the main stem 20 cm above the ground produced the highest 100-seed weight (82.19 g), seed yield per unit area (2722.5 kg.h?1), harvest index (57.53%), biological yield (6540.00 kg.h?1), oil yield (1486.76 kg.h?1), protein yield (742.66 kg.h?1), seed Zn content (12.08 ppm) and Ca content (35.86 ppm). The application of Zn nano-chelate had different positive influences on vegetative and reproductive growth of groundnut plants. Generally, optimizing of the nutritional status in groundnut plants with Ca and Zn supplements is recommended to enhance the quantitative and qualitative yield of groundnut. 相似文献
102.
Arsenic (As) and antimony (Sb) are metalloids that belong to group 15 of the periodic table and exhibit toxic properties in the environment. They mostly occur naturally at low concentrations in soil, although these can be significantly elevated in both aquatic and terrestrial food chains as a result of dispersion from anthropogenic sources, e.g., mining activities. The bioavailability, i.e., the proportion of the contaminant in soil and dust that is available for uptake by plants and other living organisms, presents the greatest risk to terrestrial ecosystems. Various in vivo and in vitro methods have been used to measure As and Sb bioaccessibility in soil and dust. In vivo measurement of bioavailability can be time consuming, expensive, and unethical; thus, in vitro methods are commonly preferred. However, there is considerable uncertainty around the efficacy of in vitro tools used to measure the bioavailable fractions of As and Sb. The results of these methods are dependent on many variables, e.g., soil characteristics, contaminant sources, and chemical composition of in vitro methods. Therefore, substantial variations are observed between in vitro and in vivo results obtained from different test animals and endpoints. In this paper, we review the literature on As and Sb bioavailability in terrestrial ecosystems and current in vivo and in vitro techniques used for assessing bioavailability and bioaccessibility of metalloids. This would reveal research gaps and allow scientists and environmental policy makers to gain a deeper understanding of the potential risks associated with these metalloids in the environment. 相似文献
103.
Wang Yang Li Ming Pei Jiubo An Tingting Saeed Muhammad Farhan Shan Te Xu Yingde Wang Jingkuan 《Journal of Soils and Sediments》2019,19(7):2882-2890
Journal of Soils and Sediments - The addition of maize residue nitrogen (N) to the soil strongly influences soil N accumulations, but the specific contributions of maize residue N to soil... 相似文献
104.
Nemati E Ghanbarpour F Taheri S Einollahi B 《Pakistan journal of biological sciences: PJBS》2008,11(6):910-914
The aim of this study is to document the prevalence of HTN and characterize risk factors associated with HTN in Iranian hemodialysis patients. Three hundred and thirty seven HD patients from 5 university based HD centers around Iran were enrolled in the study. Urea reduction ratio was calculated using formula: 100 * (1-(urea before HD/urea after HD)). Pearson Chi-square test, independent sample t-test and one way ANOVA were used for evaluations, where appropriate. Multivariate logistic regression model was used for defining independent risk factors. Two sided p < 0.05 were considered significant. Patients with diabetes mellitus and hypertension as causes of ESRD significantly were more likely to have hypertension before and after dialysis (p < 0.05). Patients with conventional thrice weekly dialysis (compared to twice), hemodialysis duration of more that 6 months, acetate type of dialysate, ESRD cause when diabetes mellitus and hypertension, were significantly associated with having pre-HD hypertension. We also found that hemodialysis center of the capital city had a significant better measures compared to other cities (p < 0.05). This study revealed a relatively acceptable prevalence of hypertension in our HD population. Nevertheless, because of higher prevalence of HTN in HD centers out of capital city, it seems necessary that we should urgently pay more attention in promotion of these centers toward achieving better outcome with implementing strict guidelines to follow. 相似文献
105.
Siyavash?SoltanianEmail author Mohammad?Saeed?Fereidouni 《Fish physiology and biochemistry》2017,43(6):1645-1655
In the current study, laboratory evaluations were made to assess the immunomodulatory effect of cypermethrin on fingerlings of common carp (Cyprinus carpio L.). Results showed that 96-h LC50 of cypermethrin in common carp was estimated at 0.85 μg/L. Fish were exposed for 21 days to cypermethrin at three sub-lethal concentrations of 0.042, 0.085, and 0.17 μg/L that represented 5, 10, and 20%, respectively, of the 96-h LC50 of the pesticide for this fish species. Blood samples were taken after 7, 14, and 21 days of exposure. Immunological indices and resistance against bacterial infection were determined. Compared to the control group, the fish exposed to cypermethrin showed a significant increase in neutrophil ratio but exhibited a significant decrease in leukocyte number and lymphocyte ratio in treatments exposed to 0.17 and/or 0.085 μg/L after 21 days of exposure (p < 0.05). Serum protein level was significantly decreased in group exposed to 0.17 μg/L on day 14 and also in groups exposed to 0.085 and 0.17 μg/L on day 21 (p < 0.05). Immunoglobulin value was significantly reduced in groups exposed to 0.085 and 0.17 μg/L after 21 days of exposure (p < 0.05). Serum lysozyme activity and phagocytic activity were significantly decreased following exposure to 0.17 μg/L determined on days 14 and 21, post-exposure (p < 0.05). Mortality rate following the challenge with Aeromonas hydrophila significantly increased in fish exposed to 0.17 μg/L of cypermethrin. Overall, the present results indicate severe immunotoxicological effects of cypermethrin in common carp. Therefore, the use of cypermethrin in the proximities of common carp farms should be carefully considered. 相似文献
106.
Phytophthora root rot caused by Phytophthora drechsleri Tucker is one of the most devastating sugar beet diseases in tropical areas. To identify genetic resources resistant to this disease, an aggressive isolate of P. drechsleri was selected. Then, a screening method was optimized based on the standard scoring scales of 1–9 (1: no symptoms, 9: complete plant death). Finally, 19 sugar beet lines, three cultivars, and 14 accessions of the wild species Beta vulgaris subsp. maritima, B. macrocarpa, B. procumbens, and B. webbiana were evaluated for resistance to the most aggressive isolate of P. drechsleri by using the optimized method (inoculum included 20 g of rice seed together with superficial wound creation). The isolates of P. drechsleri had significant variation in aggressiveness, and Kv10 was the most aggressive isolate on the susceptible variety Rasoul. The lines O.T.201-15, SP85303-0 (resistant check), and S2-24.P.107 had the lowest disease index with scores of 3.09, 3.13, and 3.27 respectively; they were categorized into the resistant group. The interaction between isolates and genotypes was not significant, which indicated the same response of each genotype to different isolates. Investigating the resistance of different generations of sugar beet revealed that progeny selection would be an effective method for increasing the resistance level of breeding materials to P. drechsleri. Among the wild species, the accession 9402 belonging to B. macrocarpa and the accession 7234 of B. vulgaris subsp. maritima had the lowest disease index (2.29 and 2.60, respectively) and were categorized into the resistant group. 相似文献
107.
Muhammad Nafees Muhammad Jafar Jaskani Saeed Ahmad Muhammad Shahid Zaffar Malik Moazzam Jamil 《The Journal of Horticultural Science and Biotechnology》2017,92(2):199-205
The present study was conducted to screen out elite pomegranates through determination of biochemical diversity in wild and cultivated genotypes for a breeding program and for fresh/processed use in industry. The results showed high morphological diversity in accessions of wild pomegranate fruits as compared to cultivated genotypes. The first six principal components covered 80.75 and 75.49% diversity in 53 wild and 62 cultivated pomegranate genotypes, respectively. High values of the coefficient of variance (10.78–18.62%), and a high range of minimum to maximum values of total soluble solids, titratable acidity, ascorbic acid content, total soluble sugars, and total phenolic content (0.10–1.25, 5.88–29.96, 9.69–19.85 and 175.05–595.42), respectively, were recorded in the studied genotypes. Ascorbic acid content had a strong correlation with antioxidant activity (0.952%), super dismutase oxides (0.94%), catalase (0.921%), and titratable acidity (0.91%). Peroxides had a strong correlation (0.88%) with catalase, and 0.81% each with super dismutase oxides and antioxidant activity. Wild and cultivated pomegranates were clustered successfully in separate groups, based on biochemical traits. A variety improvement program and selection of high-quality pomegranate genotypes could help to reduce pomegranate-related malnutrition issues in the human diet. 相似文献
108.
Wang Yang Li Shuangyi Xu Yingde Li Ming Shan Te Zhang Weijun Liu Xu Saeed Muhammad Farhan Wang Jingkuan 《Journal of Soils and Sediments》2020,20(11):3941-3950
Journal of Soils and Sediments - The distribution and dynamic of residue-derived carbon after incorporation into soil at different fertility levels have been well documented. However, the... 相似文献
109.
Previously described methods for the recovery of intestinal Trichinella worms from rodents are not feasible when applied in larger experimental animals such as foxes. In this study,worm recovery by standard technique of simple incubation of the intestine in saline was compared to embedment of the intestine in an agar gel. The small intestines of Trichinella spiralis infected foxes (4-5 days post inoculation) were slit lengthwise and the two corresponding halves were processed with one of the two incubation methods.Worms were recovered from all samples, and the total worm recovery ranged from 0.2-4.4% of the infection dose. The samples from the standard incubation were very unclear and time consuming to count compared with samples from the agar gel embedment,in which the intestinal debris were kept inside the agar. As the agar gel technique generally yielded higher numbers of worms than the corresponding standard incubation sample, it is with some optimisation, recommended for recovery of intestinal Trichinella worms from foxes. 相似文献
110.
1. Seven 35-week-old Hubbard broiler breeder males were subjected to three semen collection frequencies either once every 2 d (48 h), daily (24 h) or twice daily (12 h). 2. Semen characteristics including motility, volume, concentration and sperm numbers per ejaculate were determined for each ejaculate. 3. Sperm motility was unaffected by collection interval, but semen volume was lower at 12 than 24h intervals. Sperm concentration was lower at 12 than 48h intervals. 4. At 24 and 48 h number of sperm per collection (1.7+/-0.2, 1.8+/-0.2 x 10(9)) were higher than at 12 h (1.2+/-0.1 x 10(9)). 5. The number of semen doses over a 6-d period increased linearly as the frequency of collection increased from once every 2 d to twice daily. 6. It is concluded that output was theoretically maximal at twice daily collection, but in practice not all cockerels may be able to maintain full performance with such a demanding regime. 相似文献