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501.
Uddin Nisar Ali Niaz Nisar Mohammad Liu Mengjun Liu Zhiguo Muhammad Noor Rahman Inayat Ur 《Genetic Resources and Crop Evolution》2021,68(6):2391-2409
Genetic Resources and Crop Evolution - Research work on the genetic diversity within Pakistani and Chinese Ziziphus species is limited, and to date, no single report on the application of DNA... 相似文献
502.
Cells of two indica rice (Oryza sativa L.) varieties, one aluminum-tolerant (IAC3), and the other aluminum-sensitive (IR45), were grown in suspension culture in a medium with or without Al (0-800 µM), Si (0-2,000 µM), or Al and Si in combination as well as in R2 medium as control. The influence of Al or Si on cell growth was evaluated based on the growth of the cells in the treatment medium as well as in the R2 medium and compared with the effect on rice seedlings. Similar responses were observed for the cells and the seedlings; Al treatment resulted in a significant reduction of cell growth in both varieties, and the growth was reduced with the increase of the Al uptake by the cells. IAC3 was more tolerant to Al and it absorbed more Al than IR45. On the contrary, Si alone had almost no effect or exerted a negligible effect on the cell growth in both varieties and Si was hardly absorbed by the cells. There was a slight alleviative effect of Si on Al toxicity in the suspension cells of IR45, whereas, a considerable ameliorative effect in the seedlings. The content of total Al and of AI insoluble in citric acid in the cells were higher in the sole Al (800 µM) treatment than in the Al-Si combination treatment. This tendency was also observed in aluminon staining. The differences in the alleviative effects of Si and the uptake of Al and Si between the suspension cells and seedlings may have resulted from the presence of roots and morphological differences in the apoplastic tissues. 相似文献
503.
Md. Hasan Hafizur Rahman Yasuhiro Arima Koichiro Watanabe Hitoshi Sekimoto 《Soil Science and Plant Nutrition》2013,59(2):287-296
A pot experiment was conducted under growth chamber conditions to determine the lower and upper critical levels of boron (B) for plant growth, nodule development, and nodule acetylene reduction activity (ARA) in young soybean plants. Plants of a soybean cultivar, Tachinagaha, were grown in pots containing river sand to which a nutrient solution with different B levels was added and were inoculated with Bradyrhizobium japonicum A1017. At 8, 12, and 16 d after sowing (DAS), among the plants supplied with the solution at 0, 1.0, and 2.0 mg B L-1 , plants with 1.0 mg B L-1 showed the highest values for dry shoot and fresh root weight, root length, total number of developing nodules and meristematic nodules (DMN), and ARA. At 20 DAS plants grown with 11 B levels (0-2.0 mg L-1) were compared. The B critical deficiency levels for soybean dry shoot weight, fresh root weight, root length, DMN, number of complete nodules, and ARA were approximately 46, 35, 34, 57, 60, and 50 mg B kg-1 dry matter, and the critical toxicity levels were approximately 114, 137, 134, 97, 104, and 89 mg B kg-1 dry matter, respectively. The optimum B levels for the growth characters were approximately 34 to 137 mg B kg-1 dry matter. The optimum range of B levels for nodule formation and function was more restricted than that for the growth characters. Based on the results of treatments with various B concentrations, 0.4 mg B L-1 was found to be the concentration most beneficial for all the growth characters including nodule formation at the early stage (20 DAS) of development of soybean plants. 相似文献
504.
505.
M. Abdur Razzaque Nur Mohammad Talukder Rattan Kumar Dutta Sheikh Shawkat Zamil 《Journal of plant nutrition》2013,36(4):571-586
The effect of supplemental calcium (Ca) on the growth of three rice genotypes PVSB9, NS15, and Pokkali were assessed. Different morphological characters were studied among which the percent relative- plant height, total tillers, root dry weight (RDW), shoot dry weight (SDW), and total dry matter (TDM) were higher in Pokkali and PVSB9, but lower in NS15 under different salinity and supplemental Ca levels. These morphological characteristics significantly decreased with increasing salinity levels grown at different Ca levels, but significantly increased with increasing supplemental Ca levels. The interaction effect of genotypes and salinity levels, and genotypes and Ca levels were significant, where a negative relationship with increasing salinity levels and a positive relationship with increasing supplemental Ca levels were found. The interaction effect of salinity and Ca levels on all morphological parameters was significant, where these characteristics increased due to increasing the supplemental Ca levels at all the levels of salinity. 相似文献
506.
This study examines energy choice, consumption pattern and household energy expenditure in Khyber Pakhtunkhwa (KPK) using the Linear Approximate Almost Ideal Demand System (LA‐AIDS). The study used micro‐level data to estimate the price and expenditure elasticities by employing (SUR) methodology. Empirical findings showed that energy choice, consumption patterns, and demand are different for urban‐rural households in the province. Each household living in KPK spent 1838.81 Rupees (9.92%) on energy purchases out of its total average monthly expenditure of Rs. 18,542.79. Compared to urban households, households living in rural areas spend more on energy consumption in a proportionate manner. The expenditure elasticities estimated for all energy sources are positive and statistically significant. Furthermore, the result showed that expenditure elasticities estimated for urban and rural households are less than one, suggesting that all the sources of energy are necessities. Natural gas and electricity are the main energy sources for urban households, while firewood and electricity are key energy sources for rural households in the province. The study suggested that rural households need to switch from conventional energy sources to modern and renewable energy sources, which would reduce the cost of energy use. 相似文献
507.
Mizukami K Chang HS Ota M Yabuki A Hossain MA Rahman MM Uddin MM Yamato O 《Veterinary ophthalmology》2012,15(2):128-132
Objective To describe a Hokkaido dog, one of the traditional Japanese breeds that was affected by Collie eye anomaly (CEA), and to report the genotype of this dog and the Hokkaido dog allelic frequency of the CEA‐associated mutation. Case A nine‐month‐old intact female Hokkaido dog without any obvious visual disturbance was diagnosed ophthalmoscopically with CEA. Severe choroidal hypoplasia was observed in the bilateral temporal area adjacent to the optic nerve head, appearing as whitish areas. Therefore, the dog was suspected of possessing the CEA‐associated mutation that was previously reported as an intronic 7.8‐kilo base deletion in the canine NHEJ1 gene. Procedures SYBR Green‐based real‐time PCR with a melting curve analysis, conventional PCR with agarose gel electrophoresis, and direct DNA sequencing were carried out to determine the genotype of the dog. Furthermore, a preliminary genotyping survey was carried out in 17 Hokkaido dogs from three kennels using the real‐time PCR method, and the pedigree relationships were analyzed using their pedigree papers. Results The Hokkaido dog affected by CEA was proven to possess the CEA‐associated mutation. Of these 17 Hokkaido dogs, 12 dogs were heterozygous carriers and five dogs were affected by this mutation. The preliminary genotyping survey and pedigree analysis demonstrated that the allelic frequency of the CEA‐associated mutation is very high in Hokkaido dogs. Conclusion These data suggest that the Hokkaido breed is highly susceptible to CEA because of the known CEA‐associated mutation much like the Collie‐related breeds. 相似文献
508.
Md Nazrul Islam Khandkar-Siddikur Rahman Md Mezbaul Bahar Md Ahsan Habib Keisuke Ando Nobuaki Hattori 《Urban Forestry & Urban Greening》2012,11(4):460-464
Greenbelts are effective tools for mitigation of traffic induced air and noise pollution. In this study, the potential role of greenbelts along the roadside for the reduction of air pollution and noise levels has been assessed by using seasonally monitored data in a megacity of Bangladesh. Correlation analysis was performed between the vegetation status, measured by canopy density and shelterbelt porosity, and the total suspended particles (TSP) removal percentage. Further, the reduction of noise level was also analyzed. The results showed that the greenbelts greatly contributed to reduce TSP pollution and it was as much as 65%. Noise level reduction was also achieved up to 17 dB when compared to the open area. Moreover, TSP removal percentage was correlated to the crown density. Area having higher crown density demonstrated less air pollution and lower level of noise compared to the area having lower crown density. Greenbelt showed better performance in summer time than winter. 相似文献
509.
AS Urbasic S Hynes A Somrak S Contakos MM Rahman J Liu AL Macneill 《American journal of veterinary research》2012,73(8):1252-1261
Objective-To determine the oncolytic efficacy of an attenuated form of myxoma virus lacking the serp2 gene in canine tumor cells. Sample-Primary cells were isolated from tumors that were surgically removed from dogs and from connective tissue obtained from the cadaver of a dog. Cells of various established cell lines from tumors and nontumorous tissues were obtained. Procedures-Experiments were performed with cells in monolayer culture. Cell cultures were inoculated with wild-type myxoma viruses or myxoma viruses lacking the serp2 gene, and measures of cytopathic effects, viral growth kinetics, and cell death and apoptosis were determined. Results-Myxoma viruses replicated in cells of many of the primary and established canine tumor cell lines. Canine tumor cells in which expression of activated protein kinase B was upregulated were more permissive to myxoma virus infection than were cells in which expression of activated protein kinase B was not upregulated. Myxoma viruses lacking the serp2 gene caused more cytopathic effects in canine tumor cells because of apoptosis than did wild-type myxoma viruses. Conclusions and Clinical Relevance-Results of the present study indicated myxoma viruses lacking the serp2 gene may be useful for treatment of cancer in dogs. Impact for Human Medicine-Results of the present study may be useful for development of novel oncolytic treatments for tumors in humans. 相似文献
510.
Causes and consequences of shifting cultivation and its alternative in the hill tracts of eastern Bangladesh 总被引:1,自引:0,他引:1
Shifting cultivation, which is still prevalent in the uplands of eastern Bangladesh, contributes significantly to forest loss
and is the main cause of land degradation. This paper presents the causes and consequences of shifting cultivation and its
potential land use alternatives. The analysis presented is primarily qualitative with a supplementary quantitative analysis
of the causes of forest loss by logistic regression. The results of the study show that traditional land practices, exacerbated
by poverty and associated with a lack of technical knowledge is the main cause for the continuation of unsustainable shifting
cultivation. Population pressure, inadequate land for cultivation, low education levels, policy planning and implementation
without local participation are all factors that influence farmers’ decision to continue shifting cultivation. Intensive land
management through agroforestry is a promising alternative that can sustainably manage the remaining forest resources. If
adopted, such systems potentially provide good economic returns, and may significantly reduce rural poverty. 相似文献