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21.
Muhammad Ashraf Sher Muhammad Shahzad Muhammad Imtiaz Muhammad Shahid Rizwan Muhammad Saleem Arif Rizwana Kausar 《Archives of Agronomy and Soil Science》2018,64(9):1181-1206
Relations between nitrogen (N) nutrition and salinity tolerance in plants are multifaceted and varies significantly depending on many soil and plant factors. Saline environment might experience an N dilemma due to the opposing effects of salt ions on N uptake, translocation and metabolism within the plant body. Adequate regulation of N under saline conditions can be a promising approach to alleviate salinity’s effects on plants by ameliorating ion toxicity and nutrient imbalances through its impacts on the uptake and redistribution of salt ions within the plant. Certain N-containing compounds including proline, glycine betaine, proteins and polyamines help the plants to tolerate salinity through their involvement in improving water uptake and water use efficiency, membrane integrity, enzyme activation, hormonal balance, chlorophyll synthesis, stimulation of photosystems and CO2 assimilation under salinity stress. Nitrogen, particularly NO3? represents a stress signal that triggers the activation of antioxidant enzymes to protect the plants against salinity-induced oxidative damage. Furthermore, the source/form of N application can affect not only N-interactions but also the behavior of other nutrients in stress environment. The present review deals with N-salinity relations in plants, particularly glycophytes, emphasizing on N-induced mechanisms which can improve plant adaptation to saline environment. 相似文献
22.
Rahul Tripathi A. K. Nayak R. Raja Mohammad Shahid S. Mohanty B. Lal 《Communications in Soil Science and Plant Analysis》2017,48(10):1154-1166
Proper doses of nitrogenous fertilizer are most important for rice production system because a large part of the nitrogen may be lost if it is not applied judiciously. A study was conducted covering five blocks of Balasore and two blocks of Bhadrak districts. Soil samples were collected randomly, and field visit was conducted during peak vegetative stage of rice. Two approaches have been used in this study for estimating the site-specific nitrogen (N) requirement in the study area. In one approach, geostatisical analysis and kriging was used to develop the soil test–based N recommendation map by which a minimum of 72 kg N ha?1 and maximum of 94 kg N ha?1 were recommended. In a second approach, remote sensing was used and N recommendation map was developed using the moderate-resolution imaging spectroradiometer (MODIS) leaf area index (LAI) and normalized difference vegetation index (NDVI) satellite data, and a minimum requirement of 60 kg N ha?1 and maximum of 120 kg N ha?1 was estimated through this approach. 相似文献
23.
Muhammad Shahid Camille Dumat Bertrand Pourrut Jérôme Silvestre Christophe Laplanche Eric Pinelli 《Journal of Soils and Sediments》2014,14(4):835-843
Purpose
In spite of substantial advancement in recent past, the role of metal speciation in assessing biogeochemical behaviour of Pb is still topical. Organic ligands are capable to modify Pb speciation in nutrient/soil solution and in turn its soil–plant transfer and toxicity. In this sense, the main objective of this study was to evaluate the effect of organic ligands on Pb-induced oxidative stress to Vicia faba roots.Materials and methods
V. faba seedlings grown to controlled hydroponic system were treated with 5 μM Pb as lead nitrate in the presence and absence of organic ligands viz ethylenediaminetetraacetic acid (EDTA) and citric acid (CA) for 1, 4, 8, 12, and 24 h. The chemical speciation of Pb (percent free and chelated Pb) in nutrient solution in the presence and absence of organic ligands was calculated using Visual Minteq speciation model. The effect of chemical speciation on Pb-induced oxidative stress to V. faba roots was investigated using plant enzymatic antioxidative system [superoxide dismutases (SOD), guaiacol peroxidise (GPX), ascorbate peroxidase (APX), glutathione reductase (GR), and catalase (CAT)]. The antioxidant enzymes activities were determined using ultraviolet spectrophotometer.Results and discussion
The activities of SOD, GPX, APX, and GR significantly increased whereas that of CAT decreased in V. faba roots under Pb alone treatment. Lead-induced increase/decrease in antioxidant enzymes activities was not linear but varies with treatment exposure time. EDTA dose dependently inhibited Pb-induced changes in antioxidant enzymes activities. However, CA did not cause any significant change in Pb-induced variation in antioxidant enzymes activities, but delayed or slightly reduced the Pb effect.Conclusions
The present study suggested that physiological responses of V. faba roots to Pb toxicity vary with applied Pb form and duration of exposure. EDTA can inhibit Pb-induced toxicity to V. faba seedlings by forming stable Pb-EDTA complexes due to its high binding strength for Pb. However, CA had no effect on Pb-induced toxicity to V. faba roots due to weak complexation with Pb. 相似文献24.
Muhammad Shahid Tiantian Xiong Nasir Masood Tibo Leveque Katelle Quenea Annabelle Austruy Yann Foucault Camille Dumat 《Journal of Soils and Sediments》2014,14(4):655-665
Purpose
The present research aimed to assess the influence of two phosphorous (P) amendments on metal speciation in rhizosphere soil and the soil–plant transfer of metals.Materials and methods
Complementary experiments were performed: field experiments on a contaminated cultivated soil and laboratory experiments on an uncultivated contaminated soil to highlight the mechanisms involved in metal-phosphorous interactions. In laboratory experiment, P amendments were added at 120 mg P/kg of soluble KH2PO4 amendment and 9,000 mg P/kg of solid Ca5(PO4)3OH amendment.Results and discussion
Field-culture results showed the possible food-chain contamination due to Pb, Cd, Cu, and Zn phytoaccumulation by pea and mustard plants from a cultivated agricultural soil. Moreover, P-metal complexes were observed by microscopy in the rhizosphere soil. In laboratory experiments, the application of P amendments significantly increased Pb and Zn level in rhizosphere soil compared to control. Phosphate amendments significantly increased metal-P fraction and decreased “oxides” and “organic matter” fractions of Pb and Zn. Soluble-P amendment was more effective than solid P amendment in changing Pb and Zn speciation. The changes in metal speciation are higher in the rhizosphere soil of pea than tomato. Application of P amendments increased Pb and Zn TF root/soil but decreased TF shoot/root.Conclusions
The effectiveness of in situ metal immobilization technique varies with the type and quantity of applied P amendment as well as plant and metal type. 相似文献25.
Yuqin Wu Xiaonan Yin Youli Wang Tahir Mahmood Muhammad Shahid Dafei Yin Jianmin Yuan 《Animal Science Journal》2020,91(1)
This study was aimed to explore the comparative acidifying properties of 2‐hydroxy‐4‐(methylthio) butanoic acid (HMTBA) and a combination of DL‐methionine (DLM) and acidifier in male broiler production. A total of 480 1‐day‐old broiler chicks were randomly divided into four treatments: A (low HMTBA, 0.057% HMTBA); B (low acidifier, 0.05% DLM + 0.057% acidifier); C (high HMTBA, 0.284% HMTBA); and D (high acidifier, 0.25% DLM + 0.284% acidifier). At 21 d, growth performance, chyme pH, digestive enzyme activities, and intestinal microflora were measured. The pH of crop, gizzard, and ileum contents was higher in the HMTBA treatment group than in DLM + acidifier treatment group. Furthermore, acidifier supplementation promoted growth of butyrate‐producing bacteria such as Faecalibacterium, whereas high HMTBA (0.284%) inhibited the proliferation of acid‐producing bacteria including Roseburia and Collinsella. The chymotrypsin activity was lower in the HMTBA group than in the DLM + acidifier group. In contrast, high‐level HMTBA group showed higher average daily gain and average daily feed intake than the DLM + acidifier group. These results suggested that HMTBA work through different pathways with DLM plus acidifier. 相似文献
26.
Rahman Naeem Ur Mehmood Shahid Ahmad Sohail Javid Arshad Mahmud Athar Hussain Jibran Shaheen Muhammad Shabir Usman Muhammad Mohayud Din Hashmi Syed Ghulam 《Tropical animal health and production》2020,52(3):1125-1131
Tropical Animal Health and Production - This study examined the analysis of personal and production performance of broiler farming in 10 cities of central Punjab (Lahore, Sheikhupura, Kasur, Okara,... 相似文献
27.
Teodora Todorcic Vekic Shahid Nadeem Lars Molstad Vegard Martinsen Elisabeth Gautefall Hiis Lars Bakken Tobias Rütting Leif Klemedtsson Peter Dörsch 《Soil Use and Management》2023,39(3):1082-1095
Liming of acidic agricultural soils has been proposed as a strategy to mitigate nitrous oxide (N2O) emissions, as increased soil pH reduces the N2O/N2 product ratio of denitrification. The capacity of different calcareous (calcite and dolomite) and siliceous minerals to increase soil pH and reduce N2O emissions was assessed in a 2-year grassland field experiment. An associated pot experiment was conducted using homogenized field soils for controlling spatial soil variability. Nitrous oxide emissions were highly episodic with emission peaks in response to freezing–thawing and application of NPK fertilizer. Liming with dolomite caused a pH increase from 5.1 to 6.2 and reduced N2O emissions by 30% and 60% after application of NPK fertilizer and freezing–thawing events, respectively. Over the course of the 2-year field trial, N2O emissions were significantly lower in dolomite-limed than non-limed soil (p < .05), although this effect was variable over time. Unexpectedly, no significant reduction of N2O emission was found in the calcite treatment, despite the largest pH increase in all tested minerals. We tentatively attribute this to increased N2O production by overall increase in nitrogen turnover rates (both nitrification and denitrification) following rapid pH increase in the first year after liming. Siliceous materials showed little pH effect and had no significant effect on N2O emissions probably because of their lower buffering capacity and lower cation content. In the pot experiment using soils taken from the field plots 3 years after liming and exposing them to natural freezing–thawing, both calcite (p < .01) and dolomite (p < .05) significantly reduced cumulative N2O emission by 50% and 30%, respectively, relative to the non-limed control. These results demonstrate that the overall effect of liming is to reduce N2O emission, although high lime doses may lead to a transiently enhanced emission. 相似文献
28.
Shahid Hussain Muhammad Aamer Maqsood Rahmatullah Shamsa Kanwal 《Journal of plant nutrition》2013,36(13):1960-1969
The zinc (Zn) requirement of a maize (Zea mays L.) hybrid (‘FHY-396’) and an indigenous variety (‘EV-7004’) was measured at low (22.4 ± 5°C) and high (28.8 ± 5°C) root-zone temperatures (RZT). Four Zn rates (0, 3, 9 and 27 mg kg?1 soil) were applied to a calcareous loam soil in pots for the glasshouse study. Shoot and root dry matter yields were significantly more at the higher RZT. Regardless the RZT, maximum relative shoot dry matter yield in hybrid and variety was produced, respectively, at 9 and 3 mg Zn kg?1 soil. Zinc concentration in roots and shoots of both the cultivars increased with Zn rates and it was significantly more at the higher RZT. Cultivars differed in critical Zn concentration (CZnC) required for maximum shoot dry matter yield. The CZnC ranged from 25 to 39 μg Zn g?1 plant tissue for optimum growth of both the cultivars at low and high RZT. 相似文献
29.
Abdus Sattar Mohammad Wahid Shahid Khan Durrani 《Plant foods for human nutrition (Dordrecht, Netherlands)》1989,39(3):279-286
Different spices, dry fruits and plant nuts commonly consumed in Pakistan were assayed for the heavy metals cadmium, lead, copper, zinc, iron and manganese by the potentiometric stripping analysis and AA spectrophotometry. The results revealed wide variation in heavy metal content among different biological materials. Mixed spices generally exhibited higher value for trace metals specially lead (6.6–9.2 µg/g), cadmium (0.65–1.34 µg/g), iron (142.3–285.0 µg/g) and zinc (64.2–65.8 µg/g). Dry fruits contained relatively lesser amounts of heavy metals than plant nuts. Almonds contained higher levels of lead (1.02 µg/g) and cadmium (0.24 µg/g) than other nuts and dry fruits. 相似文献
30.
The ethanol extract of leaves of Derris uliginosa given by oral route at dose of 250 and 500 mg/kg produced a significant inhibition on acetic acid-induced writhing in mice. 相似文献