Compatibility of root growth and tuber production of potato cultivars with dynamic and static water‐saving irrigation managements          下载免费PDF全文

S. H. Ahmadi  M. Agharezaee  A. A. Kamgar‐Haghighi  A. R. Sepaskhah 《Soil Use and Management》2017,33(1):106-119

The important root characteristics of root length density (RLD) and root mass density (RMD) generally differ among irrigation managements and potato cultivars. The objective of this study was to investigate the RLD and RMD variations and their functional relationships with gross potato tuber yield for two commercial potato cultivars, Agria and Sante, under different irrigation strategies. Full irrigation and water‐saving irrigation strategies, deficit and partial root drying irrigations, were applied statically (S) and dynamically (D) based on daily crop evapotranspiration. Results showed that SPRD had significantly greater RLD (3.64 cm/cm³) and RMD (132.7 μg/cm³) than other irrigation treatments. Between the potato cultivars, Agria had significantly larger values of RLD (3.50 cm/cm³) and RMD (138.7 μg/cm³) than Sante. The functional relationship between the root growth characteristics and tuber yield showed that under water‐saving irrigations, Agria increased root mass at the expense of gross tuber yield but Sante increased root mass to maintain larger gross tuber yields. However, Agria produced more roots and gross tuber yield than Sante, and it is concluded that Agria is a more drought‐tolerant potato cultivar, which is recommended for tuber production in regions where water might be scarce. It was shown that larger root production in potatoes was associated with improved tolerance to water stress.  相似文献   

In ovo feeding of nutrients and its impact on post‐hatching water and feed deprivation up to 48 hr,energy status and jejunal morphology of chicks using response surface models          下载免费PDF全文

M. Ghanaatparast‐Rashti  M. Mottaghitalab  H. Ahmadi 《Journal of animal physiology and animal nutrition》2018,102(2):e806-e817

A Box–Behnken design (BBD) in a response surface methodology (RSM) was used to investigate the response of broiler chicks to in ovo feeding (IOF) of beta‐hydroxy beta‐methylbutyrate (HMB), dextrin and the timing of the first water and feed deprivation. On day 18th of incubation, 1,500 eggs were randomly assigned to 15 experimental runs of BBD, each with 4 replicates, as 3 levels IOF of HMB (0%, 0.5% and 1%) and dextrin (0%, 20% and 40%), and 3 levels of the first water and feed deprivation (6, 27 and 48 hr). Day‐old chicks from each replicate were then used to assess the effect of IOF and time first water and feed access on chick's responses. The IOF of dextrin leads to respectively 9.7%–15.5% lower hatchability for 20% and 40% inclusion (p < .05), whereas HMB inclusion appeared with no effect on hatchability (p > .05). Administration of dextrin or HMB into the amnion of embryos elevated length, width and surface area of villus, and increased glycogen content of liver and breast (p < .05). In all parameter models, the linear terms showed highest contribution (R² = 0.81–0.97) to explain existing variation in chick's responses. The first water and feed deprivation had largest effect on BW2 and glycogen content of liver and breast. It is concluded that if possible, place chicks before 7 hr of hatch to preserve BW loss and have maximum response from IOF. If not possible, use IOF with 40% dextrin + 0.5% HMB to preserve gut integrity and energy status up to 48 hr. This should give advantage to chicks to recover fast after feeding, but that would have to be confirmed by trials growing birds to slaughter age.  相似文献   

Effects of zinc oxide nanoparticles on the egg quality,immune response,zinc retention,and blood parameters of laying hens in the late phase of production          下载免费PDF全文

M. Abedini  F. Shariatmadari  M. A. Karimi Torshizi  H. Ahmadi 《Journal of animal physiology and animal nutrition》2018,102(3):736-745

The objective of this study was to evaluate the effects of dietary supplementation with zinc oxide nanoparticles (ZnO‐NPs) on the performance, egg quality, Zn retention, immunity responses, superoxide dismutase activity (SOD), egg malondialdehyde (MDA) content, and serum parameters in laying hens in the late phase of production. A total of 288 laying hens at 64 weeks of age were randomly assigned to 4 treatments with 6 replicates, and 12 birds within each group. Experimental diets included a corn‐soybean meal‐based diet (without Zn supplementation) and a basal diet supplemented with 80 mg/kg of Zn‐oxide, ZnO‐NPs, and Zn‐methionine. The results indicated that egg production and egg mass were significantly higher in the Zn‐methionine and ZnO‐NPs groups (p < .05). Also, eggshell thickness and shell strength increased in the ZnO‐NPs group as compared with the other groups (p < .05). Moreover, Zn supplementation decreased egg loss (p < .05). There were significant differences among treatments in Zn deposition in tibiotarsus, liver, pancreas, eggs, and excreta (p < .01). Antibody titre, heterophil (%(, and phytohemagglutinin (PHA) were significantly higher in birds fed with Zn‐supplemented diets (p < .05). In treatments supplemented with ZnO‐NPs and Zn‐methionine, the SOD activity in the liver, pancreas, and plasma was greater as compared with the other treatments (p < .05). The MDA content in eggs was significantly reduced in groups supplemented with Zn (p < .01). Moreover, dietary Zn supplementation significantly affected serum total protein, albumin, glucose, alkaline phosphatase activity, carbonic anhydrase activity, and Zn level (p < .05). In conclusion, this study demonstrated that dietary supplementation with ZnO‐NPs can improve the performance of laying hens. Therefore, ZnO‐NPs can enhance zinc absorption in the intestine of aged layers and can be a more suitable source of zinc than regular Zn‐oxide in diets.  相似文献   

Direct somatic embryogenesis in Epipactis veratrifolia,a temperate terrestrial orchid     

Shirin Moradi  Mostafa Arab  Kourosh Vahdati 《The Journal of Horticultural Science and Biotechnology》2017,92(1):88-97

Most temperate terrestrial orchids are endangered species. Attempts to produce plantlets from plants of the genus Epipactis by asexual methods have totally failed. This study was conducted using somatic embryogenesis as a rapid vegetative propagation technique for conservation of E. veratrifolia. For these purposes, effects of different types of plant growth regulators (PGRs), different types of explants, light and dark conditions, and the effect of gibberellic acid (GA₃) and Paclobutrazol (PBZ) were investigated on somatic embryogenesis induction. Abscisic acid (ABA) pre-treatment effectiveness on inducting somatic embryogenesis and increasing the number of embryos per explant were investigated. Subsequently, 16 media were tested to find the best medium for plant regeneration and shoot and root proliferation. BA (3 mg L^?1) resulted in a better response than the other PGRs by supporting the development of 17 embryos per protocorm. PBZ, which resulted in 11 embryos per explant, was better than GA₃. FAST medium supplemented with organic substances was recognized as the best medium for plant regeneration and shoot and root proliferation. ABA pre-treatment had positive effect on somatic embryogenesis initiation. This study, for the first time, succeeded in finding a rapid and suitable protocol for propagation and genetic resource conservation of E. veratrifolia.  相似文献   

Genomic Prediction of Arsenic Tolerance and Grain Yield in Rice: Contribution of Trait-Specific Markers and Multi-Environment Models     

Nourollah Ahmadi  Tuong-Vi cao  Julien Frouin  Gareth J. Norton  Adam H. Price 《水稻科学》2021,28(3):268-278

Many rice-growing areas are affected by high concentrations of arsenic(As). Rice varieties that prevent As uptake and/or accumulation can mitigate As threats to human health. Genomic selection is known to facilitate rapid selection of superior genotypes for complex traits. We explored the predictive ability(PA) of genomic prediction with single-environment models, accounting or not for trait-specific markers, multi-environment models, and multi-trait and multi-environment models, using the genotypic(1600 K SNPs) and phenotypic(grain As content, grain yield and days to flowering) data of the Bengal and Assam Aus Panel. Under the base-line single-environment model, PA of up to 0.707 and 0.654 was obtained for grain yield and grain As content, respectively; the three prediction methods(Bayesian Lasso, genomic best linear unbiased prediction and reproducing kernel Hilbert spaces) were considered to perform similarly, and marker selection based on linkage disequilibrium allowed to reduce the number of SNP to 17 K, without negative effect on PA of genomic predictions. Single-environment models giving distinct weight to trait-specific markers in the genomic relationship matrix outperformed the base-line models up to 32%. Multi-environment models, accounting for genotype × environment interactions, and multi-trait and multi-environment models outperformed the base-line models by up to 47% and 61%, respectively. Among the multi-trait and multi-environment models, the Bayesian multi-output regressor stacking function obtained the highest predictive ability(0.831 for grain As) with much higher efficiency for computing time. These findings pave the way for breeding for As-tolerance in the progenies of biparental crosses involving members of the Bengal and Assam Aus Panel. Genomic prediction can also be applied to breeding for other complex traits under multiple environments.  相似文献   

Effect of in vitro exposure to Vibrio vulnificus on hydroelectrolytic transport and structural changes of sea bream (Sparus aurata L.) intestine     

Khemiss F  Ahmadi S  Massoudi R  Ghoul-Mazgar S  Safta S  Moshtaghie AA  Saïdane D 《Fish physiology and biochemistry》2009,35(3):541-549

The everted gut sac technique has been used to investigate the effect of Vibrio vulnificus on water and electrolyte (Na⁺, K⁺, Cl⁻, HCO₃ ⁻) transport on the intestine of sea bream (Sparus aurata L.). Both the anterior and the posterior intestine were incubated in a medium containing 10⁸ V. vulnificus cells ml⁻¹ at 25°C for 2 h. The presence of V. vulnificus resulted in a significant reduction (P < 0.05) of water absorption in the anterior intestine, while sodium absorption in the anterior (P < 0.01) and posterior (P < 0.05) intestine was elevated. Chloride absorption was increased, but the changed was not significant, while potassium absorption decreased significantly (P < 0.05), but only in the posterior intestine. Incubation the sea bream intestine with V. vulnificus did not affect carbonate secretion in the anterior segment, whereas high secretion was stimulated in the posterior segment (P < 0.01). Histological evaluations demonstrated damage in the anterior intestine of sea bream that was characterized by the detachment of degenerative enterocytes, alterations in the microvilli, and the presence of a heterogenous cell population, indicating inflammation. Based on our results, we conclude that V. vulnificus caused cell damage to the intestine of sea bream and that the anterior intestine is more susceptible than the posterior part of the intestine. Several hypotheses are suggested to explain our observations, such as the presence of higher numbers of villosities in the anterior intestine than in the posterior one and/or the presence of endogenous bacteria in the posterior intestine which may have a protector role.  相似文献   

Effects of Salinity and Soil–Drying on Radiation Use Efficiency,Water Productivity and Yield of Quinoa (Chenopodium quinoa Willd.)     

F. Razzaghi  S. H. Ahmadi  S.‐E. Jacobsen  C. R. Jensen  M. N. Andersen 《Journal of Agronomy and Crop Science》2012,198(3):173-184

Drought and salinity reduce crop productivity especially in arid and semi‐arid regions, and finding a crop which produces yield under these adverse conditions is therefore very important. Quinoa (Chenopodium quinoa Willd.) is such a crop. Hence, a study was conducted in field lysimeters to investigate the effect of salinity and soil–drying on radiation use efficiency, yield and water productivity of quinoa. Quinoa was exposed to five salinity levels (0, 10, 20, 30 and 40 dS m^?1) of irrigation water from flower initiation onwards. During the seed‐filling phase the five salinity levels were divided between two levels of irrigation, either full irrigation (FI; 95 % of field capacity) or non‐irrigated progressive drought (PD). The intercepted photosynthetically active radiation was hardly affected by salinity (8 % decrease at 40 dS m^?1) and did not differ significantly between FI and PD. Radiation use efficiency of dry matter was similar between salinity levels and between FI and PD. In line with this, no negative effect of severe salinity and soil–drying on total dry matter could be detected. Salinity levels between 20 and 40 dS m^?1 significantly reduced the seed yield by ca. 33 % compared with 0 dS m^?1 treatment owing to a 15–30 % reduction in seed number per m², whereas the seed yield of PD was 8 % less than FI. Consequently, nitrogen harvested in seed was decreased by salinity although the total N‐uptake was increased. Both salinity and drought increased the water productivity of dry matter. Increasing salinity from 20 to 40 dS m^?1 did not further decrease the seed number per m² and seed yield, which shows that quinoa (cv. Titicaca) acclimated to saline conditions when exposed to salinity levels between 20 and 40 dS m^?1.  相似文献   

The inheritance and chromosomal location of morphological traits in wild wheat, Triticum turgidum L. ssp. dicoccoides     

Hadi Ahmadi  Farhad Nazarian 《Euphytica》2007,158(1-2):103-108

The homoeologous groups of chromosomes carrying the genes for some morphological traits in wild wheat Triticum turgidum L. ssp. dicoccoides (T. dicoccoides) were determined, but not the actual chromosomes carrying them. The objectives of this study were to investigate the modes of inheritance, and determine the chromosomes carrying some morphological traits in wild emmer (2n = 28; AABB), the progenitor of most cultivated wheats. To investigate the inheritance of morphological traits, crosses were made between T. turgidum L. ssp. durum (T. durum cultivar Chartokhmi (IR10) and T. dicoccoides accessions TA1150 and TA1131. F₂ seeds from each cross were grown in the field and six qualitative characters were investigated. Purple coleoptile, purple auricle, purple culm, hairy auricle, hairy rachilla, and fragility of spike were controlled by single dominant genes. To determine the chromosomal locations, accession TA1131 was crossed with the complete set of LDN D-genome disomic substitution lines. Assessments of F₂ populations showed that chromosomes 7A, 6A, 7B, 5B, 5A and 3B carried genes for purple coleoptile, purple auricle, purple culm, hairy auricle, hairy rachilla and brittle rachis, respectively.  相似文献   

High-accuracy ab initio rotation-vibration transitions for water     

Polyansky OL  Császár AG  Shirin SV  Zobov NF  Barletta P  Tennyson J  Schwenke DW  Knowles PJ 《Science (New York, N.Y.)》2003,299(5606):539-542

The spectrum of water vapor is of fundamental importance for a variety of processes, including the absorption and retention of sunlight in Earth's atmosphere. Therefore, there has long been an urgent need for a robust and accurate predictive model for this spectrum. In our work on the high-resolution spectrum of water, we report first-principles calculations that approach experimental accuracy. To achieve this, we performed exceptionally large electronic structure calculations and considered a variety of effects, including quantum electrodynamics, which have routinely been neglected in studies of small many-electron molecules. The high accuracy of the resulting ab initio procedure is demonstrated for the main isotopomers of water.  相似文献   

Effects of diazinon on biochemical parameters of blood in rainbow trout (Oncorhynchus mykiss)     

M. Banaee  A. SuredaA.R. Mirvaghefi  K. Ahmadi 《Pesticide biochemistry and physiology》2011,99(1):1-6

Existence of diazinon, an organophosphorous pesticide, in river waters of Iran near rice paddy fields has been reported by some authors. The present research aimed to determine the acute toxicity and evaluate the effect of sub-lethal concentrations of diazinon on some biochemical parameters of rainbow trout, Oncorhynchus mykiss after 7, 14 and 28 days. No significant differences were observed in the plasma levels of creatinine among the treatment groups at different sampling intervals. Acetylcholinesterase activity and the levels of total protein, albumin as well as globulin in plasma were significantly reduced at both concentrations tested (p < 0.05). Lactate dehydrogenase activity was only decreased on 7th day in 0.1 mg/L diazinon treatment (p < 0.05). Creatine kinase activity was significantly lower in 0.1 mg/L diazinon group at 14th and 28th sampling periods, whereas its activity significantly increased in fishes exposed to 0.2 mf/L diazinon only on 7th day (p < 0.05). Aspartate aminotransferase, alanine aminotransferase activities and glucose levels in diazinon treated groups were significantly higher than the controlled group at experimental periods (p < 0.05). In conclusion, long-term exposure to diazinon at sub-lethal concentrations induced biochemical alterations in rainbow trout, and offers a simply tool to evaluate toxicity-derived alterations.  相似文献