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A 2-year field experiment using a randomized complete block design with the treatments arranged as split-split-plot with three replicates was conducted to investigate the effects of different sowing dates. Different irrigation regimes and different triticale cultivars were tested during 2014 and 2015 growing seasons. Under cutting off irrigation at the milk development stage, Sanabad with 46.2% had higher relative water content on December 3 sowing date. Assimilate remobilization in cutting off irrigation at dough development was more than that at milk development and Sanabad had the highest assimilate remobilization on 3 December sowing date in both years. In both years, Sanabad had the highest remobilization efficiency. The highest contribution of pre-anthesis assimilates to grain was obtained on 3 December sowing date in both years in Sanabad. Lower grain yield in Juanillo cultivar under cutting off irrigation, appeared to be due to reduction in remobilization efficiency, especially by cutting off irrigation at milk development stage in late sowing date. Overall, Sanabad was more tolerant to cutting off irrigation than Juanillo. 相似文献
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Roghayeh Shahriaripour Ahmad Tajabadipour Isa Esfandiarpoor Vahid Mozafary 《Journal of plant nutrition》2019,42(11-12):1277-1282
Developing a fast and reliable soil testing method is critical for improving soil testing efficiency and ensuring reliable fertilizer recommendation. The objectives of this study were to evaluate sodium ethylene diamine tetra acetic acid (Na2-EDTA) as a replacement for ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA) to extract phosphorus (P) to determinate the relationships between extractable P and its uptake by crop in calcareous soils. Na2-EDTA and AB-DTPA was compared by the amounts of extracted P by analyzing soil samples collected from agricultural production areas. There were significant correlations between Na2-EDTA and AB-DTPA for soil test P based on soils collected from the agricultural field. Soil test P by both extractants was significantly correlated with plant P concentration. Na2-EDTA was identified as an alternate improved extraction method instead of AB-DTPA in calcareous soils based on this study. However, more work will be needed to identify the correlation of the two extractants and crop responses under a field condition. 相似文献
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Vahid Nasiri Ali.A.Darvishsefat Reza Rafiee Anoushirvan Shirvany Mohammad Avatefi Hemat 《林业研究》2019,(3):943-957
Temporal land use/land cover (LULC) change information provides a variety of applications for informed management of land resources. The aim of this study was to detect and predict LULC changes in the Arasbaran region using an integrated Multi-Layer Perceptron Neural Network and Markov Chain analysis. At the first step, multi-temporal Landsat images (1990, 2002 and 2014) were processed using ancillary data and were classified into seven LULC categories of high density forest, low-density forest, agriculture, grassland, barren land, water and urban area. Next, LULC changes were detected for three time profiles, 1990–2002, 2002–2014 and 1990–2014. A 2014 LULC map of the study area was further simulated (for model performance evaluation) applying 1990 and 2002 map layers. In addition, a collection of spatial variables was also used for modeling LULC change processes as driving forces. The actual and simulated 2014 LULC change maps were cross-tabulated and compared to ensure model simulation success and the results indicated an overall accuracy and kappa coefficient of 97.79% and 0.992, respectively. Having the model properly validated, LULC change was predicted up to the year 2025. The results demonstrated that 992 and 1592 ha of high and lowdensity forests were degraded during 1990–2014,respectively, while 422 ha were added to the extent of residential areas with a growth rate of 17.58 ha per year. The developed model predicted a considerable degradation trend for the forest categories through 2025, accounting for 489 and 531 ha of loss for high and low-density forests, respectively. By way of contrast, residential area and farmland categories will increase up to 211 and 427 ha, respectively. The integrated prediction model and customary area data can be used for practical management efforts by simulating vegetation dynamics and future LULC change trajectories. 相似文献
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Keyvan Karami Saeed Zerehdaran Ali Javadmanesh Mohammad Mahdi Shariati Hossien Fallahi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(3):205-216
Imprinted genes display biased expression of paternal and maternal alleles in mammals. They are marked through epigenetic process during gametogenesis. Characterization of imprinted genes has expanded our understanding of the regulation and function of genes. In the current study, 22 experimentally validated imprinted genes in bovine (Bos Taurus) were analysed. Several supervised machine learning algorithms and attribute weighting methods were used to find characteristics of different types of imprinted genes and suggest a classification method for finding maternally and paternally expressed genes in bovine. For assessing the best model and comparing attributes in other organisms, we have also conducted a comparative analysis for human and sheep imprinted genes. According to the results of the present study, GC contents 10 and 100 kb upstream, Gly and Gln amino acids, Ile/ATC codon usage, LINE and SINE in 100kbup and length of first intron were significantly different between the maternal and paternal genes in cattle. Considering all species together, we found that GC content 100 kb up, LINE 100 kb up and the frequency of amino acids like Gly, Gln and Met were the most important attributes for identifying the paternal and maternal imprinted genes. These findings could imply conservation pattern in the attributes among these species. 相似文献
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Cryopreservation of Persian sturgeon (Acipenser persicus) sperm: effects of cryoprotectants,antioxidant, membrane stabilizer,equilibration time and dilution ratio on sperm motility and fertility 
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下载免费PDF全文 Three experiments were performed to develop protocols for cryopreservation of Persian sturgeon Acipenser persicus, sperm. In the first experiment, sperm from six males was individually split in three subsamples and cryopreserved using Modified Tsvetkova's extender (mT) supplemented with dimethyl sulfoxide (DMSO), methanol (MeOH), glycerol (Gly) and ethylene glycol (EG) at concentration of 5%, 10%, 15% and 20%. In the second set of experiments, the effects of six equilibration times (0, 5, 10, 20, 40 and 60 min) and dilution ratios (volume sperm: volume extender 1:0.5, 1:1, 1:2, 1:3, 1:5 and 1:10) and the additive advantage of bovine serum albumin (BSA; 0, 2.5, 5 and 10 mg mL?1) and ascorbic acid (0, 2.5, 5 and 10 U mL?1), on the post‐thaw survival of sperm (triplicate set of six fish) were evaluated. Then, sperm was diluted in 1:1 mT extender with 10 mg mL?1 BSA with selected cryoprotectants (15% MeOH and 10% DMSO) for 5 min. After a month of storage in liquid nitrogen, post‐thawed sperm motility; fertilization and hatching rate and viability of derived larvae were measured (Exp.3). Evaluation of cryoprotectants efficiency showed that MeOH 15% and DMSO 10% were suitable for cryopreservation of Persian sturgeon sperm. Gly and EG resulted in very low post‐thaw motility rates even at lowest concentration. No significant difference was observed among the four different equilibration times (0, 5, 10, 20 min) (P > 0.05) although higher equilibration times than 20 min resulted low post‐thaw motility (P < 0.05). The motility of frozen–thawed sperm did not significantly change when dilution ratio was increased from 1:0.5 to 1:3 (P > 0.05). However, higher dilution ratios (1:5 and 1:10) reduced the percentage of motile sperm. Supplementation of the cryoprotectant solution with 10 mg mL?1 BSA significantly improved post‐thaw motility (P < 0.05), but ascorbic acid did not improve post‐thaw motility (P > 0.05). The results of experiment 3 showed that the highest fertilization (30.2 ± 5.75) and hatching rates (28.2 ± 5.25) were observed when samples were frozen with 15% MeOH (P > 0.05). Our study indicates that the use of mT extender consisting of 10 mg mL?1 BSA in 15% MeOH diluted with sperm at 1:1 ratio for 5 min can be recommended cryopreservation method for Persian sturgeon sperm. 相似文献
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Akbar Abbaszadeh Vahid Yavari Seyed Javad Hoseini Mahmod Nafisi Mansour Torfi Mozanzadeh 《Aquaculture Research》2019,50(4):1162-1176
A 5‐week study was performed to evaluate the effect of spoilage date extract (SDE) as the biofloc carbon source on Litopenaeus vannamei (5.4 ± 0.3 g) performance. The two levels of dietary protein (15% and 25% crude protein) and two carbohydrate sources (molasses‐M and SDE‐P) were tested including: M15, M25, P15 and P25. The minimum (0.2 ± 0.0 mg/L) and the maximum (0.5 ± 0.0 mg/L) of total ammonia nitrogen were observed in the P15 and M25 groups respectively. The highest protein efficiency ratio (6.1 ± 0.3) and protein productive value (112.3 ± 5.8%) were found in the P15 group (p < 0.05). No significant difference was found between biofloc treatments in the expression of cathepsin L gene in hepatopancreas (p > 0.05). The number of total haemocyte count (THC), semigranular cells (SGC) and granular cells (GC) of shrimp in SDE‐based biofloc treatments was relatively higher than those in molasses‐based biofloc treatments. Following the white spot syndrome virus (WSSV) challenge, a significant decrease in THC, SGC, GC and hyaline cell values was observed in all treatments (p = 0.001). Plasma biochemical parameters were significantly influenced by dietary protein levels, biofloc carbon sources as well as WSSV challenge test. In conclusion, SDE successfully could be used as an alternative carbon source for establishing a biofloc system in L. vannamei production. 相似文献
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The accuracy of the knowledge of mass transfer parameters(effective moisture diffusivity,mass transfer Biot number and mass transfer coefficient) in the case of frying food,is essential and important for designing,modeling and process optimization.This study is undertaken to develop an approach for determining mass transfer parameters during frying of spherical rice cracker in sunflower oil at 150,170 and 190 ℃.These parameters were evaluated from the plots of dimensionless concentration ratios against time of frying.Effective moisture diffusivity,mass transfer Biot number and mass transfer coefficient ranged between 1.24×10-8 to 2.36×10-8 m2/s,1.96 to 2.34 and 5.51×10-6 to 9.70×10-6 m/s,respectively.Effective moisture diffusivity and mass transfer coefficient were found to increase with an increasing frying temperature,whereas mass transfer Biot number decreased.An Arrhenius-type relationship was found between effective diffusivity coefficient and frying temperature. 相似文献
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Vahid Tavallali 《Journal of plant nutrition》2017,40(11):1588-1603
The effects of zinc (Zn) and boron (B) on some physiological and biochemical characteristics of pistachio (Pistacia vera L. cv. Badami) seedlings were evaluated in a greenhouse study. It was found that both high levels (10 and 20 mg B kg?1 soil) and also lack of B account for the reduction in growth and photosynthesis parameters, especially at low Zn levels. Moreover, Zn deficiency resulted in a reduction in the net photosynthetic rate and stomatal conductance. However, the adverse effects of B deficiency and toxicity were alleviated by increasing Zn levels up to 10 mg kg?1 soil. In addition, provided that B and Zn are adequate, synergism can be observed between the two nutrients. This is because sufficient amounts B accelerated the effects of Zn by raising the plant dry weight, photosynthesis parameters, carbonic anhydrase activity, and chlorophyll contents. This increase was reported higher in comparison with Zn alone application. It was concluded that Zn may act as a scavenger of reactive oxygen species (ROS) for mitigating the injury on biomembranes under B stress. Adequate concentration of Zn also prevents uptake and accumulation of excess B in leaf by increasing membrane integrity of root cells. Similarly, B application in adequate concentration plays an important structural role in the cell wall and influences a great variety of physiological processes in pistachio seedlings. 相似文献