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排序方式: 共有311条查询结果,搜索用时 265 毫秒
51.
Azhar Abbas Muhammad Yaseen Muhammad Khalid Muhammad Naveed Muhammad Zahir Aziz Yasir Hamid 《Journal of plant nutrition》2017,40(16):2303-2311
A field experiment was conducted to evaluate effect of biochar-amended urea on nitrogen economy of soil for improving the growth and yield of wheat under field condition. Experiment plan was comprised of twelve treatments with four replications including treatments without application of urea and biochar (control) and urea only. Biochar was applied at 1–10% of the weight of urea fertilizer applied each treatment. Results showed that application of biochar at 10% with recommended dose of urea significantly improved plant height, spike length, number of tillers, number of spikelet per spike, 1000 grain weight, grain yields, biomass yield, harvesting index, nitrogen (N) concentration and uptake in grain and straw, and agronomic efficiency of nitrogen by 6.0%, 11.1%, 32.0%, 55.3%, 5.4%, 38.0%, 19.0%, 9.0%, 19.0%, 26.0%, 65.0%, 50.0%, and 63.0%, respectively, as compared to treatment comprised of recommended rate of nitrogen without biochar. 相似文献
52.
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
53.
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
54.
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
55.
Two eggplant cultivars, Dilnasheen and Bemisal, were selected to assess whether pure GB and sugarbeet extract could effectively ameliorate the harmful effects of salt stress on eggplant (Solanum melongena L.), under saline conditions. Salt stress markedly suppressed the growth, yield, photosynthetic capacity, internal CO2 level, transpiration, and stomatal conductance in both cultivars. Potassium (K+) and Ca2+ contents and K+/Na+ ratios of both root and leaf were also reduced, while GB and proline in leaves, and Na+ and Cl− contents in roots and leaves were significantly enhanced. Exogenously applied glycinebetaine and sugarbeet extracts significantly counteracted the salt-induced adverse effects on growth, yield, various gas exchange characteristics, GB and leaf K+, Ca+, Cl− and Na+. However, GB and sugarbeet extract showed differential effects on photosynthetic rate, stomatal conductance and transpiration, internal CO2 level, Ci/Ca ratio, leaf K+, Ca2+, and Cl− contents, and K+/Na+ ratio. Sugarbeet extract proved better than the GB in improving growth, photosynthetic rate, transpiration, stomatal conductance, yield and GB accumulation. Since, sugarbeet extract contains a substantial amount of GB along with a variety of other important nutrients so it was found as effective as pure GB in improving growth and some key physiological processes in eggplant under salt stress. Thus, it can be used as an alternative cheaper source of GB for its use as an ameliorative agent for protecting plants against the hazardous effects of salt stress. 相似文献
56.
57.
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
58.
Diacetyl (DA), a natural butter flavorant, is a causative agent for the lung disease obliterative bronchiolitis. Mutagenic properties of 1,2-dicarbonyls have previously been empirically linked to their possible interaction with DNA nucleobases. This study for the first time identifies chemically the adduct of DA with 2-deoxyguanosine. Selective reactivity of DA with 5'-TTTGTTTTT-3' over 5'-TTTTTTTTT-3' indicated its propensity to modify specifically the guanosine residue. Treatment of plasmid DNA, pBR322, with DA induced changes in electrophoretic mobility that are typical of ternary structure disruption. Such DNA nucleobase interaction of DA translated into increased apoptosis in DA-treated SH-SY5Y cells in a dose-dependent manner (IC(50) = 0.114 ± 0.0421 mM). The traditional carbonyl scavengers metformin, 2-thiobarbituric acid, and d-penicillamine protected cells from DA toxicity in proportion to their rates of reaction with DA, with d-penicillamine causing a maximal increase in the IC(50) to 5.23 ± 0.0992 mM when co-incubated with DA. 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.
Assessment study on the use of Pawpaw; Carica papaya seeds to control Oreochromis niloticus breeding
This study was carried out to assess the ability of using pawpaw (Carica papaya) seeds as a natural reproduction inhibitor for tilapia fish (Oreochromis niloticus) culture to control its breeding. Biochemical, physiological and histopathological effects ofpawpaw seeds on male tilapia fish were also determined. Mature male tilapia were stocked for 4 weeks and treated with low dose (3 g/kg/day) and high dose (6 g/kg/day) of ground dried pawpaw seeds mixed with their feed. The obtained results showed that the pawpaw seeds induced permanent sterility in the high dose treated fish while the low dose treatment showed reversible results. The results also demonstrated that fish treated with high dose of pawpaw exhibited higher biochemical and physiological effects as: low meat quality, a progressive fall in erythrocyte (RBCs) count, hemoglobin (Hb) content and haematocrit values. Also the high dose revealed a significant increase in the leukocytes (WBCs) count, serum glucose, total protein, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine and uric acid levels. Moreover, serum total lipids revealed a significant decrease compared to control group. On the other hand, the low dose treatment revealed lower biochemical and physiological changes. Histological sections of testis showed disintegration of sperm cells and focal necrosis of seminefrous tubules in the high dose treated fish, hepato-pancreas and posterior kidney tissues also showed severe changes in high dose treated fish. Milder degenerative changes in some necrotic foci and slight changes in hepato-pancreas and posterior kidney were observed in the low dose treated fish. The study concluded that pawpaw seeds which are cheap and easy to obtain, can be incorporated into fish feeds with adjusted amount and be used to control breeding of tilapia fish in growing ponds instead of unfavorable and expensive hormonal use. 相似文献