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231.
Hossein Zakariapour Bahnamiri Mahdi Ganjkhanlou Abolfazl Zali Mostafa Sadeghi Hossein Moradi Shahrbabak Gholam Ali Nehzati Paghaleh 《Journal of animal physiology and animal nutrition》2019,103(2):427-435
Fat‐tailed sheep breeds can tolerate periods of negative energy balance without suffering from elevated concentration of plasma non‐esterified fatty acid (NEFA). This ability was attributed to unique metabolism of fat‐tailed adipose depot, whereas role of liver as an influential organ in fatty acid metabolism was not evaluated yet. Hence, current study was conducted to evaluate the effects of negative and positive energy balances on liver expression of genes related to fatty acid metabolism in fat‐tailed and thin‐tailed lambs. Lambs experienced negative (21 days) and positive (21 days) energy balances and were slaughtered at the beginning and end of negative energy balance and at the end of positive energy balance. Real‐time quantitative polymerase chain reaction (RT‐Q‐PCR) was conducted to evaluate changes in gene expression. Expression of diglyceride acyltransferase 1 (DGAT1), 3‐hydroxy‐3‐methylglutaryl‐CoA synthase 2 (HMGCS2) and apolipoprotein B (APOB) was not affected by genotype, energy balance and their interaction. Expression of carnitine palmitoyltransferase 1 (CPT1) was significantly higher in liver of fat‐tailed comparing to thin‐tailed lambs regardless of energy balance (p < 0.02). Catalase mRNA abundance was increased in response to negative energy balance (p < 0.02), and severity of this enhancement was higher in fat‐tailed lambs (p < 0.06). Expression of CPT1 was positively correlated with expression of HMGCS2 in both fat‐tailed (p < 0.05) and thin‐tailed lambs (p < 0.002); however, the correlation was weaker in fat‐tailed lambs (0.72 vs. 0.57, respectively, for thin‐tailed and fat‐tailed lambs). There was a positive correlation between DGAT1 and APOB genes expression in fat‐tailed lambs (0.94; p < 0.001), whereas this correlation was not observed in thin‐tailed lambs. Results demonstrate that liver of fat‐tailed lambs has higher capacity for metabolism of mobilized NEFA exposed to liver during negative energy balance. 相似文献
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233.
Masoumeh Pouresmael Ramazan Ali Khavari-Nejad Javad Mozafari Farzaneh Najafi Foad Moradi 《Archives of Agronomy and Soil Science》2013,59(12):1675-1693
Crop drought tolerance improvement is one of the most challenging objectives of plant breeding programs. Developing an efficient screening technology and access to genetic variation for the traits contributing toward drought tolerance are major steps in this direction. To go in this quest, an experiment was conducted under controlled condition in a greenhouse. Nine Kabuli chickpea genotypes were grown under well-watered condition (85–90% field capacity (FC)) until start of flowering. Then, the following water treatments were imposed: well-watered, intermediate (55–60% FC), and severe (25–30% FC) drought stress. Physiological and agronomical traits were compared under different water treatments. Drought stress and genotypes interaction was significant in all measured traits, indicating that various genotypes responded differently to drought stress. Among measured traits, electrolyte leakage, stomatal conductance, yield components, and harvest index exhibited the highest variations. Yield components and stomatal conductance showed maximum reduction under drought stress and in susceptible known genotype, ILC3279, reduction reached up to 95%. Principal component analysis indicated that relative water content, photochemical efficiency of photosystem II, and stomatal conductance are the physiological traits with greater contribution toward drought tolerance. Therefore, these traits should be evaluated ahead of many other traits in making selections for drought-tolerant chickpea genotypes. 相似文献
234.
Maryam Goodarzian Ghahfarokhi Syrus Mansurifar Ruhollah Taghizadeh-Mehrjardi Mohsen Saeidi Amir Mohammad Jamshidi Elahe Ghasemi 《Archives of Agronomy and Soil Science》2013,59(4):493-506
Drought is a problem of the expanding universe which seriously influences crop production and quality. Approximately one-third of the cultivated area of the world suffers from constantly inadequate supplies of water. The present study aimed to determine the effects of drought and rewatering on activities of antioxidant enzymes, chlorophyll, proline, and relative water contents (RWC). In this experiment, six maize hybrids (Sc260, Sc370, Sc500, Sc647, Sc700, and Sc704) were examined in a pot study during the maize-growing season of 2011. Results indicated that the growth of hybrids was retarded under drought stress conditions and regained growth speed during rewatering. RWC, chlorophyll, and carotenoid contents were markedly decreased by the water deficit and reached normal values during rewatering in Sc647, Sc704, and Sc700. Our findings also indicated significantly higher activity levels of peroxidase and catalase and proline content in water-stressed plants than in well-watered plants, which decreased when the plants were rewatered, showing an inverse relationship to gluthatione reductase activity. According to the results, the better upregulation of the protective mechanism in Sc704 and Sc647 probably induced higher drought resistance. We concluded that antioxidant enzyme activity could provide a useful tool for depicting drought tolerance in maize hybrids in arid and semiarid regions. 相似文献
235.
Nik Muhamad Majid M. M. Islam Melina E. Nap Maryam Ghafoori Arifin Abdu 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):101-108
Abstract Heavy metals are dangerous environmental pollutants that can be transferred and accumulated in human and animal bodies causing deoxyribonucleic acid (DNA) damage and carcinogenic effects. A glass house experiment was conducted to evaluate the potential of Justicia gendarussa Burm F. to absorb heavy metals from textile industry sludge. Justicia gendarussa seedlings were planted on six different growth media (soil+sludge) comprising: 100% soil, 100% sludge, 80% sludge+20% soil, 60% sludge+40% soil, 40% sludge+60% soil and 20% sludge+80% soil. The maximum height increment and number of leaves were found in 20% sludge+80% soil while the highest basal diameter increment was recorded in the 100% sludge. Copper and iron were highly concentrated in the roots, zinc in the leaves, while aluminium was concentrated in both leaves and stems. Justicia gendarussa seems to have a high potential to absorb high amounts of Al and Fe in the leaves and roots. This species showed high translocation (TF) and low bioconcentration factor (BCF) in the contaminated soil. Justicia gendarussa was able to tolerate and accumulate a high concentration of heavy metals. Therefore, this species can be considered as a potential phytoremediator. 相似文献
236.
Abstract Can humic acid (HA) and glutamic acid (GA), when added to tomato (Lycopersicon esculentum Mill. cv. ‘Hongyangli’) nutrient solution in a hydroponic system, improve growth? Tomato seedlings were grown in six nutrient solutions: (1) control (C), (2) C + 25 mg L?1 HA (HA1); (3) C + 50 mg L?1 HA (HA2); (4) C + 100 mg L?1 GA; (5) HA1 + GA; (6) HA2 + GA. Various biochemical and physiological parameters were measured. HA increased photosynthesis rate and mesophyll conductance. HA did not significantly affect transpiration, stomatal conductance, titratable acidity, or antioxidant activity. In addition, GA improved protein and sugar content, mesophyll conductance and yield. The combination of HA and GA was more effective, especially with 50 mg L?1 HA. The activity of superoxide dismutase (SOD) and peroxidases (POD) did not change in the presence of HA or GA. Malondialdehyde (MDA) content increased by 30% in HA2 together with GA. HA has a positive effect on tomato hydroponic growth when applied with GA. This expands the use of HA and GA for horticultural commodities in hydroponic systems. 相似文献
237.
Hamideh Heydari Maryam Rezayian Hassan Ebrahimzadeh 《Soil Science and Plant Nutrition》2013,59(3):243-250
ABSTRACTSesame (Sesamum indicum L.) is one of the world’s important oil crops. The aim of the present study was to investigate the effects of salt stress on physiological and biochemical parameters of sesame and assess the improvement of salt tolerance by Penconazole (PEN). Plants were treated with various NaCl concentrations (0, 50, 100, and 200 mM) without or with PEN (15 mg L?1). Salt stress inhibited the growth in sesame. Our results showed sesame plant under salinity used of the enzymatic and non-enzymatic system and compatible osmolytes to overcome on oxidative and osmotic stress, respectively. PEN improved the growth and reduced the negative effects of salinity in sesame. In fact, PEN increased the resistance of this plant under salt stress by improving the antioxidant system and osmotic regulation. Thus, this compound can be used as stress-ameliorating agents in this crop plant. 相似文献
238.
Hamid Yaghini Maryam Shirani Azin Archangi Karim Sorkheh Sajad Badfar Chaleshtori Seyed Ehsan Sangi Mahmood Khodambashi Farahnaz Tavakoli 《Euphytica》2013,194(3):305-324
Nineteen agrochemical traits of 20 almond inter-specific backcrosses progenies were evaluated and compared for three consequence years to find out their phenotypic diversity and determine the relationships of fruit quality traits in almond × peach backcrosses breeding progenies. The variation was observed for traits of phenology parameters (blooming time, ripening time), Physical parameters (fruit weight, width, height, shape, thickness, skin pubescences, colour and flower type), chemical parameters (total sugar content, soluble solids content and acidity) and sensory parameters (attractiveness, taste, and flavor) and yield. Many fruit characteristics that are important to breeders are present in this collection. A high variability was found in the evaluated almond progenies and significant differences were found among them in all studied quality attributes. Year-by-year variations were observed for majority of traits. A significant correlation was found among the fruit height, fruit width, skin pubescences and yield. Fruit height showed a significant positive correlation with fruit weight and fruit thickness and some other traits and a negative correlation with the titratable acidity, skin pubescences and fruit flavour. A high negative correlation was found between the fruit weight and titratable acidity (?0.8). Low coefficients were got between the flower colour and skin pubescences. In addition, principal component analysis it possible to established similar groups of genotypes depending on their quality characteristics and to study relationships among pomological traits in almond progenies evaluated. 相似文献
239.
Hamid Hoseinian Khoshro Alireza Taleei Moahmmad Reza Bihamta Maryam Shahbazi Alireza Abbasi 《Journal of Crop Science and Biotechnology》2013,16(3):173-181
Osmotic adjustment is the main component for physiological machinery of wheat drought tolerance. Some of parameters implicated in osmotic adjustment in 15 bread wheat cultivars were evaluated at soil water deficits (50% FC) and FC as the control in the greenhouse. For the physiological traits, analysis of variance showed that there are highly significant differences between treatments, i.e. water stress levels and wheat cultivars. Shahpasand and Marvdasht as sensitive wheat cultivars had significantly lower osmotic adjustment, relative water content, K+ content, soluble sugar, proline, and glycine betaine levels than the rest of the cultivars. The results of cluster analysis revealed that all cultivars were grouped into three distinct clusters. Dez, Kavir, Pishtaz, and Maron cultivars which have the highest osmoregulation activity were in cluster I, whereas clusters II (Pishgam, Aflak, Hirmand, Zagros, and Vee/Nac) and III (Ws-89-2, Sardari, Azar2, Shapasand, and Marvdasht) had intermediate activity and the lowest capacities for osmoregulation, respectively. In addition, in wheat flag leaf during the reproductive stage under drought conditions, the changes in gene expression of two key genes namely P5CS (D-Pyrroline-5-carboxylate synthetase) and BADH (Betaine Aldehyde Dehydrogenase) in two selected cultivars including Dez and Marvdasht revealed that water stress can increase the expression level of the genes P5CS and BADH in the resistant cultivar, Dez, compared with Marvdasht, the sensitive one. In general, it seemed that application of the all cultivars in cluster I would enable breeders to acquire more reliable achievements under drought conditions. 相似文献
240.
Simulation of 1D surface and 2D subsurface water flow and nitrate transport in alternate and conventional furrow fertigation 总被引:3,自引:0,他引:3
Hamed Ebrahimian Abdolmajid Liaghat Masoud Parsinejad Enrique Playán Fariborz Abbasi Maryam Navabian 《Irrigation Science》2013,31(3):301-316
Increasing water and fertilizer productivity stands as a relevant challenge for sustainable agriculture. Alternate furrow irrigation and surface fertigation have long been identified as water and fertilizer conserving techniques in agricultural lands. The objective of this study was to simulate water flow and fertilizer transport in the soil surface and in the soil profile for variable and fixed alternate furrow fertigation and for conventional furrow fertigation. An experimental data set was used to calibrate and validate two simulation models: a 1D surface fertigation model and the 2D subsurface water and solute transfer model HYDRUS-2D. Both models were combined to simulate the fertigation process in furrow irrigation. The surface fertigation model could successfully simulate runoff discharge and nitrate concentration for all irrigation treatments. Six soil hydraulic and solute transport parameters were inversely estimated using the Levenberg–Marquardt optimization technique. The outcome of this process calibrated HYDRUS-2D to the observed field data. HYDRUS-2D was run in validation mode, simulating water content and nitrate concentration in the soil profiles of the wet furrows, ridges and dry furrows at the upstream, middle and downstream parts of the experimental field. This model produced adequate agreement between measured and predicted soil water content and nitrate concentration. The combined model stands as a valuable tool to better design and manage fertigation in alternate and conventional furrow irrigation. 相似文献