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241.
Seyed Ali Hosseini Seydeh Zohreh Mirdeilami Fatemeh Ghilishli 《Journal of plant nutrition》2017,40(9):1323-1331
Information on different rangeland plants' nutritive values on different plant parts and for various habitats is important in rangelands management. Effects of different plant parts (stems and leaves) of the Jasminum fruticans L. plant species on forage quality indicators were investigated in two regions in 2015. Plant samples were collected from Sharlogh rangelands and cultivated in the Research and Education Center of Agricultural and Natural Resources (RECANR) in Iran with completely randomized design with three replications in each plant sample. The plant leaves and stems samples were oven-dried at 80°C for 24 hr, and then analyzed for crude protein (CP), crude fiber (CF), dry matter (DM), ether extract (EE), crude ash (CA), metabolizable energy (ME), and mineral elements, including calcium (Ca) and phosphorus (P). Results showed that the forage quality indicators in different regions were statistically significant, except for the CA. Also, nutritive values differed significantly (p < 0.01) between different plant parts, except ME parameter. Results also indicated that J. fruticans due to its high tissue CP content is a valuable source of forage for livestock. 相似文献
242.
Raouf Seyed Sharifi Razieh Khalilzadeh Jalal Jalilian 《Archives of Agronomy and Soil Science》2017,63(3):308-318
In order to study the effects of biofertilizers and cycocel on some physiological and biochemical characteristics of wheat (Triticum aestivum L.) under salinity condition, a factorial experiment was conducted based on randomized complete block design with three replications under greenhouse condition in 2015. Treatments were included salinity in four levels [no salt (control or S0), salinity 30 (S1), 60 (S2) and 90 (S3) mM NaCl equivalent of 2.76, 5.53 and 8.3 dS m?1, respectively], four biofertilizers levels [no biofertilizer (F0), seed inoculation by Azotobacter chrocoocum strain 5 (F1), Pseudomonas putida strain 186 (F2), both inoculation Azotobacter + Pseudomonas (F3)] and three cycocel levels [without cycocel as control (C0), application of 600 (C1) and 1000 (C2) mg L?1]. Results showed that salinity severe stress (90 mM) decreased chlorophyll content, relative water content (RWC), total chlorophyll, photochemical efficiency of PSII and yield of wheat. Whereas, soluble sugars and proline content, electrical conductivity (EC), the activity of catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO) enzymes were increased. Similar results were observed in CAT, POD and PPO activities due to inoculation by biofertilizers and cycocel. Salinity at 30 mM increased the photochemical efficiency of PSII and chlorophyll content in plants grown under biofertilizer and cycocel treatment but with increasing salinity up to 90 mM mentioned parameters were decreased. The highest proline and soluble carbohydrate at all salinity levels were observed in plants treated in the highest cycocel level and Azotobacter+ Pseudomonas application. Generally, it was concluded that biofertilizers and cycocel can be used as a proper tool for increasing wheat yield under salinity condition. 相似文献
243.
Sadegh Saffari Saeed Keyvanshokooh Mohammad Zakeri Seyed Ali Johari Hossein Pasha-Zanoosi Mansour Torfi Mozanzadeh 《Fish physiology and biochemistry》2018,44(4):1087-1097
An 8-week feeding trial was conducted to compare the effects of supplementing (0.7 mg kg?1) different dietary selenium (Se) sources including organic [selenomethionine (SeMet)], inorganic [sodium selenite (Na2SeO3)], and nanoparticulate Se (nano-Se) on physiological responses of common carp, Cyprinus carpio juveniles (9.7?±?0.1 g). Basal diet without Se supplementation used as control. Fish fed nano-Se supplemented diet had the highest weight gain (97.2?±?10.8%) and feed efficiency ratio (42.4?±?0.8%). Intestinal villi height was significantly taller in fish fed nano-Se diet than in the control group in both foregut and midgut sections. Serum glutathione peroxidase and superoxide dismutase activities were significantly higher in nano-Se and SeMet groups than in control and sodium selenite groups. Fish fed Se-supplemented diets had greater red blood cell counts and hematocrit and hemoglobin values than the control group (P?<?0.05). Nano-Se and SeMet groups showed a significant increase in white blood cell counts, neutrophil percentage, and serum lysozyme activity than the other groups. Fish fed nano-Se diet had the highest serum hemolytic activity, total immunoglobulin, and total protein and albumin contents, as well as the lowest serum total cholesterol and low density lipoprotein levels (P?<?0.05). Overall, significant improvements in growth performance, feed utilization, intestinal morphology, and hemato-immunological and serum biochemical parameters of common carp juveniles suggest nano-Se as an efficient source for providing dietary Se in this species. 相似文献
244.
Seyed Mohammad Moein Sadeghi John Toland Van Stan Thomas Grant Pypker Jelveh Tamjidi Jan Friesen Moein Farahnaklangroudi 《European Journal of Forest Research》2018,137(1):121-130
The temporal dynamics of forest canopy rainfall partitioning are important to forest ecology and management as it influences all subsequent hydrological processes along the rainfall-to-discharge flow path. Despite a growing body of literature on the importance of coupled hydrological–ecological interactions during periodic forest life cycle events, little work has examined how canopy rainfall partitioning varies across transitional leaf states (between the leafed vs. leafless states). This study analyzed a 3 year field monitoring campaign for two tree species in semiarid Iran (Robinia pseudoacacia and Platanus orientalis) to describe rainfall partitioning dynamics across the full-leaf, senescence, leafless, and leafing states. Crown saturation point, canopy storage capacity, free throughfall coefficient and the ratio of wet canopy evaporation rate to mean rainfall intensity were related to decreases/increases in plant area index and canopy closure. The high variability of rainfall partitioning observed in this study highlights the importance of transitional leaf states in the temporal characterization of water inputs to forest surfaces and boundary layer. 相似文献
245.
Muhammad Asif Shehzad Muhammad Maqsood Fahim Nawaz Tasawer Abbas Sanaullah Yasin 《Journal of plant nutrition》2018,41(8):943-955
Terminal drought stress (drought at reproductive growth stage) has been considered a severe environmental threat under changing climatic scenarios and undoubtedly inhibits sunflower production. A field study was conducted to explore the potential role of foliar applied boron (B) (0, 15, 30, 45 mg L?1) at late growth periods of sunflower in alleviating the adversities of terminal drought stress (75, 64, 53 mm DI) grown from inflorescence emergence to maturity stages. The plant water relations such as leaf relative water content (RWC), water potential (Ψw), osmotic potential (Ψs), and turgor pressure (Ψp) were increased significantly with B foliar sprays while exposed to terminal drought stress. Foliar B application considerably improved the nitrogen and B concentrations in leaf and seed tissues, and also chlorophyll a and b pigments under terminal drought stress conditions. Drought-induced proline accumulation prevented the damages caused by drought stress, nevertheless, B foliar spray increased its contents. Compared to well-watered conditions, terminal drought stress substantially declined the growth performance in terms of reduced leaf area index (LAI), crop growth rate (CGR), net assimilation rate (NAR), and total dry matter (TDM) production; however, foliar B supply (30 mg L?1) might be helpful for improving drought tolerance in sunflower with reduced growth losses. 相似文献
246.
Muhammad Naeem Muhammad Shahbaz Naeem Rashid Ahmad Muhammad Zahid Ihsan Muhammad Yasin Ashraf Yasir Hussain 《Archives of Agronomy and Soil Science》2018,64(1):116-131
Water and nutrient restrictions are the factors that limiting growth of maize in arid/semi-arid climate. Calcium (Ca2+) uptake is affected severely under drought stress (DS). The objectives of this study were to investigate the effects of DS and foliar applied Ca2+ on growth, physiological, biochemical, yield and grain-nutrient content in two maize cultivars i.e. drought-tolerantDekalb-6525 and drought-sensitive Yousafwala-hybrid. The study comprised of two phases; firstly the best rate of Ca2+ (20, 40 and 60 mg L?1) was evaluated. Secondly, optimized rate of Ca2+ (40 mg L?1) was used to assess physio-biochemical and yield responses of maize under DS. The applied DS caused significant reduction in maize growth, water-status, photosynthesis and grain nutrient contents. Foliar Ca2+ markedly improved plant growth, water-potential (18%), turgor-potential (75%), photosynthesis (45%), stomatal-conductance (47%), transpiration rate (43%) and accumulation of total soluble sugars (20%) along with decline in H2O2 content (23%) in both cultivars under DS. Furthermore, optimized rate of Ca2+ improved maize grain yield and quality under water-deficit conditions. Cultivar Dekalb-6525 presented significant response to Ca2+ over Yousafwala-hybrid. Results of the study surmise that foliar supply of Ca2+ is an effective approach to make plants vigorous to thrive under limited-water supply. 相似文献
247.
248.
Effect of date palm (Phoenix dactylifera) seed extract as a dietary supplementation on growth performance immunological haematological biochemical parameters of common carp 下载免费PDF全文
Maryam Mohammadi Mehdi Soltani Ali Siahpoosh Seyed Pezhman Hosseini Shekarabi Mehdi Shamsaie Mehrgan Alan Lymbery 《Aquaculture Research》2018,49(8):2903-2912
This study aimed to assess the effect of date palm (Phoenix dactylifera) seed (DPS) extract at 0.5%, 1%, 2% and 4% as a dietary supplement over 60 days, on the growth and immune‐physiology of common carp (Cyprinus carpio) fingerlings. The weight gain in fish fed with 0.5% DPS was significantly greater than other treatments and fish fed a control diet with no DPS (p < 0.05). With increasing DPS dosage above 0.5%, weight gain and growth rate gradually declined. Feed conversion ratio in fish fed 0.5% DPS was lower than other treatments, but not significantly so, except for the highest DPS concentration (4%). With respect to immunophysiological variables, fish treated with 0.5% DPS leucocyte, neutrophil, lymphocyte and monocyte counts that were generally equivalent to fish on a control diet, but significantly lower than fish treated with greater concentrations of DPS (p < 0.05). Chemilumincene response and lysozyme activity, as well as levels of total protein and albumin, were higher in all treated groups than the control. The highest levels of iron and high density lipoprotein (HDL) were observed in fish fed with 0.5% DPS, while the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP), glucose, cholesterol, triglyceride, low density lipoprotein (LDH), thyrotropin, thyroxine and triiodothyronine were lower level in fish fed with 0.5% DPS than in all other treatments. In aquaculture practice, use of 0.5% DPS in commercial carp feed can improve the growth rate and condition of fish. 相似文献
249.
Potassium(K) is known as one of the essential nutrients for the growth of plant species. The relationship between K and clay minerals can be used to understand the K cycling, and assess the plant uptake and potential of soil K fertility. This study was conducted to analyze the K forms(soluble, exchangeable, non-exchangeable and structural) and the relationship of K forms with clay minerals of calcareous soils in Kohgiluyeh and Boyer-Ahmad Province, Southwest Iran. The climate is hotter and drier in the west and south of the province than in the east and north of the province. A total of 54 pedons were dug in the study area and 32 representative pedons were selected. The studied pedons were mostly located on calcareous deposits. The soils in the study area can be classified into 5 orders including Entisols, Inceptisols, Mollisols, Alfisols and Vertisols. The main soil clay minerals in the west and south of the study area were illite, chlorite and palygorskite, whereas they were smectite, vermiculite and illite in the north and east of the province. Due to large amount of smectite and high content of organic carbon in soil surface, the exchangeable K in surface soils was higher than that in subsurface soils. It seems that organic matter plays a more important role than smectite mineral in retaining exchangeable K in the studied soils. Non-exchangeable K exhibited close relationships with clay content, illite, vermiculite and smectite. Although the amount of illite was the same in almost all pedons, amounts of structural and non-exchangeable K were higher in humid regions than in arid and semi-arid regions. This difference may be related to the poor reservoir of K~+ minerals like palygorskite and chlorite together with illite in arid and semi-arid regions. In humid areas, illite was accompanied by vermiculite and smectite as the K~+ reservoir. Moreover, the mean cumulative non-exchangeable K released by CaCl_2 was higher than that released by oxalic acid, which may be due to the high buffering capacity resulting from high carbonates in soils. 相似文献
250.
Mousavi SH Chobert JM Bordbar AK Haertlé T 《Journal of agricultural and food chemistry》2008,56(18):8680-8684
The changes of structure and ligand binding properties of beta-LG B have been studied by fluorescence and circular dichroism spectroscopy in ethanolic solutions. Fluorescence measurements of retinol/beta-LG interactions at 480 nm in various ethanol concentrations show that the maximal fluorescence intensity induced by this interaction between retinol and beta-LG is observed around 20% v/v of ethanol. It is reduced to zero at 40% and 50% of ethanol. These results suggest that there are two distinct structural changes in beta-LG occurring between 20% and 30% and around 40% of ethanol. The first transition, which increases affinity and the apparent number of binding sites for retinol, may be related or similar to the Tanford transition. The strong quenching of retinol emission at 480 nm in 40% of ethanol indicates the radical transformation of beta-LG tertiary structure and the release of retinol. CD spectra at the aromatic region show that secondary and tertiary structures of beta-LG are not significantly affected between 0% and 20% of ethanol. In 30% of ethanol, beta-sheet percentage of beta-LG decreases with respect to native beta-LG (from 55% to 46%). beta-Sheet percentage in beta-LG increases in 40% and 50% alcohol (51% and 53%) relative to 30% of ethanol, which also indicates the strong rearrangement of the secondary structure of beta-LG, while its tertiary structure and beta-LG interactions are radically changed. 相似文献