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51.
Muhammad Abbas Javaid Ahmed Shah Muhammad Irfan Muhammad Yousuf Memon 《Journal of plant nutrition》2018,41(12):1522-1533
A solution culture study was conducted to compare the phosphorus (P) remobilization efficiency of four wheat cultivars under induced P deficiency. Wheat cultivars, i.e. Sarsabz, NIA-Sunder, NIA-Amber and NIA-Saarang were initially grown on adequate P nutrition for 30 days and then exposed to P-free nutrient solution for next 15 days to study P remobilization. Completely randomized design (CRD) with ten replicates per cultivar was employed. Cultivars varied for biomass production, P concentration, P uptake, and P utilization efficiency at both harvests. Overall, more than 75% of absorbed P was mobilized from older leaves to younger leaves as well as roots of all cultivars during P-omission period. However, cultivars could not produce significant variations (P < 0.05) in P remobilization, which implied that P remobilization was only a stress response to P deficiency in wheat cultivars and it could not be related to P utilization efficiency of these cultivars. 相似文献
52.
Arezoo Soltani Prem L. Sankhayan Ole Hofstad Farshid Eshraghi Abbas Arabmazar 《Small-Scale Forestry》2017,16(3):347-365
Construction of new roads in rural areas is closely linked to market accessibility and economic growth. It also leads to exploitation of natural resources that may accelerate deforestation. These conflicting effects of an improved road network on rural development and depletion of forest resources present a serious challenge to policy makers interested in sustainable development. This paper investigates the effects of road networks on biological and socio-economic behaviour. The analysis was conducted by using a non-linear bio-economic model for a community in southern Zagros, Iran where they manage the adjoining forest according to traditional rules. Data for the model were obtained through village surveys and published resources. The model followed a holistic approach by incorporating a number of livelihood activities, such as, crop cultivation, goat husbandry, charcoal production and hiring out of community labour, along with several logical resource constraints. It was run over a period of 45 years. The results showed that new roads can either fuel forest degradation or contribute to forest protection depending on the choice of policy options. The study concludes that construction of new roads should be accompanied by policies aimed at higher state controls over newly accessible forest areas through regulatory measures, creation of new non-farm employment opportunities and strengthening of traditional institutions through providing extension services for local communities and facilitating NGO involvement so as to minimize the adverse effects on forest resources. 相似文献
53.
为了查明新疆乌鲁木齐县石人沟地区的地衣物种多样性及其区系和群落特征,在石人沟地区的不同植被带设立16个样点,对地衣进行了样方调查、标本采集和标本鉴定,并对地衣区系成分和生长型进行了分析。结果表明,石人沟地区地衣共有30种,隶属于17属,10科,5目,其中叶状地衣和壳状地衣种类较丰富。地衣区系成分划分为世界广布成分、环北极成分、温带成分、中亚物种和中国特有物种等5个区系成分;按照该地区地衣生长的现状,把其划分为岩面生、树生、藓丛生和地面生等4个类型;该地区地衣的生长型主要以壳状地衣为主,其次为叶状地衣,缺乏枝状地衣种类。同时基于30种地衣及盖度数据,应用双向指示种分析方法(TWINSPAN)和除趋势对应分析(DCA)将该地区的地衣划分为3个样点组,并计算了物种多样性和均匀度指数。 相似文献
54.
Tasawer Abbas Muhammad Ather Nadeem Asif Tanveer Hafiz Haider Ali Amar Matloob 《Archives of Agronomy and Soil Science》2017,63(11):1613-1622
A field survey was conducted for the sampling of Acetyl-CoA carboxylase (ACCase) inhibitor resistance littleseed canarygrass, a major weed of wheat, from Punjab, Pakistan in 2014 for confirmation of resistance. The surveyed regions encompassed four different cropping systems including rice–wheat, maize–wheat, cotton–wheat and mixed cropping. Dose–response assay was conducted for confirmation of resistance. Efficacy of herbicide mixtures including clodinafop–propargyl, metribuzin, pinoxaden and sulfosulfuron at a range of doses was investigated to manage littleseed canarygrass. Results revealed that all populations were resistant to fenoxaprop except PM-BWL-2. The higher level resistance (6.5) was found in populations collected from rice–wheat cropping system. The tested herbicide mixtures at 75% and 100% of the recommended dose of each mixture component provided the effective control of resistant littleseed canarygrass. Mixtures at 50% provided more than 80% control and reduced growth and seed production potential of surviving plants. The confirmation of ACCase inhibitor resistance as the first case of herbicide resistance in Pakistan, leads us to discourage use of ACCase inhibitor herbicides alone. However, herbicide mixtures at 75% and 100% of the recommended dose are suggested to manage this weed for sustainable wheat production in the surveyed cropping systems. 相似文献
55.
M. S. Abbas M. Akmal Saif Ullah M. U. Hassan S. Farooq 《Communications in Soil Science and Plant Analysis》2017,48(14):1659-1668
Cadmium (Cd) is a nonessential and toxic element because it inhibits the growth and development of plants and is dangerous for end consumer. It enters in the human food chain through food crops. Application of plant nutrients such as zinc (Zn) and gypsum is a viable and cheap strategy to minimize its accumulation in edible plant portions. Therefore, this investigation was conducted to determine the effectiveness of Zn and gypsum against Cd accumulation in wheat. The results showed that Cd toxicity considerably decreased the plant growth, physiological activities, and yield attributes and increased the Cd accumulation in root, shoot, and grain, while application of Zn and gypsum remarkably increased the growth and yield and decreased the Cd accumulation in plant parts in Cd-contaminated soil. The results also depicted that application of Zn showed better results as compared to gypsum. In conclusion, we can say that application of Zn and gypsum remarkably ameliorated the Cd toxicity and decreased its accumulation in wheat, grown in Cd-contaminated soil. 相似文献
56.
Rabbani H Ostadkarampour M Danesh Manesh AH Basiri A Jeddi-Tehrani M Forouzesh F 《Iranian Biomedical Journal》2010,14(3):77-82
Background: The ectopic expression of receptor tyrosine kinase Ror1 has been reported in patients with hematological malignancies such as chronic lymphocytic leukemia and acute lymphoblastic leukemia. Here we report, for the first time, expression of ROR1 gene in both tumor tissues and peripheral blood mononuclear cells (PBMC) from patients with renal cancer (RC). Methods: In the current study, the expression of ROR1 gene was semi-quantitatively measured in PBMC and tumor tissues from 16 RC patients as well as PBMC from 22 healthy individuals relative to the expression of the housekeeping gene phosphoglucomutase 1 by RT-PCR. Results: Our results showed that ROR1 was expressed at gene level in 81.3% of renal tumor tissues (13 out of 16) whereas it was expressed in 94% of PBMC from RC patients (15 out of 16). A weak expression of ROR1 was observed in PBMC of 4 out of 22 healthy individual. A significant expression of ROR1 was observed in PBMC from RC patients when compared to that in PBMC from normal healthy individuals (P<0.001). The expression of ROR1 in PBMC may reflect a shedding of tumor cells into blood stream. Conclusion: We conclude that detection of a high level of ROR1 expression in blood cells might assist in early detection of renal malignancies, providing taking into consideration the clinical symptoms of the disease. Key Words: ROR1, Ectopic expression, Renal cancer 相似文献
57.
58.
M. F. Abbas J. H. Al-Niami E. A. Al-Sareh 《The Journal of Horticultural Science and Biotechnology》2013,88(5):627-629
Mature green jujube fruits of cv. Zaytoni were subjected to gamma radiation doses of 0, 10, 30 and 50 krad. The irradiated and unirradiated fruits were then kept at 20°C and 85-90% r.h., and changes in weight loss, total soluble solids, titratable acidity and ascorbic acid content were determined. Fruits subjected to 30 krad were firmer and greener than unirradiated control fruits after six days of storage, and this treatment delayed ripening by three days. There was no significant loss in the nutritive value of the fruit due to irradiation. 相似文献
59.
Much of inland Australia has been in perpetual drought since 1997 except during 2010 when above average rainfall occurred. It has been the worst drought since 1788 when European settlement began. Water scarcity poses a serious threat to the sustainability of the irrigated agriculture in major irrigation systems across the Murray-Darling Basin (MDB). There is a need for water-saving measures and a structured approach to assess water loss in earthen supply channels. This paper presents such an approach to assess and reduce seepage losses for improving irrigation efficiencies. Main elements of this approach are the following: field measurements, hydrologic modelling, potential options for seepage reduction, economic analysis and financing water-saving investments. Using data from two irrigation systems in the southern MDB, a case is made for reducing seepage water losses in irrigation supply channels in a cost-effective manner using low-cost technologies. Increasing the level of security for investments in water-saving programs provides incentives to key stakeholders to achieve water-saving targets. Considering the value of water recovered from reducing seepage loss at irrigation system level, this study demonstrates how reducing just one component (seepage) from the total water losses in irrigation systems can help improve water supplies as well as the environmental flows. Potential options for financing infrastructure improvement for saving irrigation water are proposed and discussed. 相似文献
60.
Melahat A. Birsin M. Sait Adak Ali Inal Abbas Aksu Aydin Gunes 《Journal of plant nutrition》2013,36(2):267-284
Growth stage effects on distribution of mineral nutrients or beneficial elements phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chloride (Cl), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), molybdenum (Mo), sodium (Na), silicon (Si) and nickel (Ni), and the elements bromine (Br), rubidium (Rb), strontium (Sr), barium (Ba), lanthanum (La), cerium (Ce), and uranium (U) in two barley (Hordeum vulgare L.) cultivars and how the distribution of these elements changed were determined during the 2006–2007 growing season in a field experiment. Barley plants were sampled from the field at shooting, heading, soft dough, hard dough and harvest stages, and mineral nutrients and other elements concentrations of spike, flag leaf, old leaf, and stem samples were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Distribution patterns varied considerably from element to element. At the end of the season much of the Ca, Mg, S, Si, Fe, Mn, Cu, Ni, Sr, Ba, La, Ce, and U were located in the spikes. However, much of the P, K, Zn, Cl, Na, Br, and Rb remained in the old leaves or stem. 相似文献