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Drought is currently one of the most severe abiotic factors limiting agricultural production. The high rates of population growth and global warming are expected to further exacerbate the threat of drought, especially in areas with a semi-arid climate as in the Middle East region. Selecting genotypes for improved drought tolerance has long been of interest for those involved in horticulture. The present research investigated the reaction of seven 10-year-old olive genotypes to drought stress in Dallaho Olive Research Station, Iran. To determine the reaction of genotypes to drought stress, physiological and biochemical characteristics, fruit and oil yield, and water use efficiency were measured. The results showed that different genotypes react differently to drought stress while drought decreased vegetative and reproductive traits such as shoot length and diameter, relative water content of the leaves, Ca and K percentage, and fruit yield. Finally, Dd1 and Bn6 showed the highest oil and fruit yield per hectare and the highest water use efficiency. In addition, Bn3 had a favorable status in most of the measured parameters. So, they can be suggested as the genotypes that are tolerant of drought stress. The results also showed that olive yield and irrigation management can be improved by applying proper irrigation levels and using tolerant genotypes. 相似文献
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Roostaei Mozaffar Jafarzadeh Jaffar Roohi Ebrahim Nazary Hossein Rajabi Rahman Haghparast Reza Mohammadi Reza Abediasl Gholam Reza Khalilzadeh Gholam Reza Seif Fereshteh Mirfatah Seyyed Mohammad Mehdi 《Euphytica》2021,217(9):1-1
Soybean mosaic virus (SMV) is a member of genus Potyvirus, which causes worldwide soybean [Glycine max (L.) Merr.] yield loss and seed quality deterioration. It is of great significance to find new resistance loci and genes for cultivation of soybean variety. In the present study, a recombinant inbred line (RIL) population and a genome-wide association study (GWAS) panel, which contained 193 lines and 379 germplasms, respectively, were used for QTL mapping of resistance to SMV. Linkage mapping identified a major QTL, qSMV13, on chromosome 13, conferring resistance to SMV SC3 and SC7 strains, explaining phenotypic variations 71.21 and 76.59?%, respectively. The QTL qSMV13 was located close to the known SMV resistance loci Rsv1-h. GWAS analysis revealed five single nucleotide polymorphisms (SNPs) significantly associated with resistance to SC3 on chromosomes 2, 11, 13, 14 and 16. One of the SNP markers, ss715614844, was the right flanking marker of qSMV13. Combining linkage mapping and GWAS analysis enabled us to delimit qSMV13 in a 97.2-kb genomic region containing seven genes. A LRR-RLK protein was proposed as the candidate gene of qSMV13. These results provided selection markers and candidate genes for SMV resistance in soybean molecular breeding programs.
相似文献104.
Bijan Esmaeilnejad Mousa Tavassoli Siamak Asri-Rezaei Bahram Dalir-Naghadeh Seyyed Meysam Abtahi Froushani Jafar Arjmand Mostafa Golabi 《Tropical animal health and production》2014,46(7):1217-1221
This study is designated to assess the effect of the severity of Babesia ovis infection on sialic acid concentration in blood sera in naturally infected sheep. Infected animals (diseased group) comprised 38 Iranian fat-tailed sheep, about 1–3 years old, naturally infected with B. ovis, divided into four subgroups with respect to parasitemia rates (low 0.1–0.3 %, moderate 0.4–0.9 %, high 1–2.5 %, and very high >2.5 %). The parasitological diagnosis was confirmed using PCR analysis. As a control group, ten clinically healthy sheep reared under the same management and environmental conditions were also sampled. Hematological parameters and the concentrations of total sialic acid (TSA), lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured in both groups. Compared to controls, sialic acid concentrations showed significant increase (p?Parasitemia rate was positively correlated with sialic acid concentrations. This study demonstrated that B. ovis infection induced marked and persistent elevations of serum sialic acid concentrations. It seems that increase of serum sialic acid concentrations during parasitemia alter receptor-ligand interactions, which are known to play important role in immune response. Furthermore, sialic acid would indirectly inhibit the action of leukocytes and consequently promote the evasion of the immune response and persistence of the parasite in the host. This factor could influence the parasite-host cell adhesion, but further detailed biochemical investigations are needed to precisely explain the exact role of sialic acid in invasion process of the parasite to the host cells. 相似文献
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Gypsum-bonded particleboard （GBPB） panels were made from various mixtures of particles of bagasse （Saccharum officinarum L.） and wheat straw （Triticum aestivum L.）, bonded with different ratios of particle/gypsum. This study examined the feasibility of bagasse and wheat straw particles in the production of GBPB. One-layer experimental GBPBs with a density of 1.05 or 1.20 g.cm-3 were manufactured at different ratios of bagasse/wheat straw, i.e., 100%/0%, 93.75%/6.25%, 87.5%/12.5%, 75%/25%, 50%/50%, 25%/75% and 0%/100% using two particle/ gypsum composite ratios, i.e., 1/2.75 and 1/3.25 by weight. Thickness swelling （TS）, water absorption （WA）, modulus of rupture （MOR）, modulus of elasticity （MOE） and internal bond strength （IB） properties of the boards were evaluated and a statistical analysis was performed in order to examine the possible feasibility of these agricultural residues for use in commercial GBPB manufacturing. We determined that WA of panels decreases as the amount of straw increases to 100% and the LR/G （wood/gypsum） ratio decreases to 1/3.25, whereas the TS of panels decreases as the proportion of straw decreases to 0% and the LR/G ratio increases to 1/2.75. The experimental results also show that the MOR and MOE of panels containing 0%, 6.25% and 12.5% wheat straw with a LR/G ratio of 1/2.75 were higher than those of panels made from 25%-100% wheat straw with a LR/G ratio of 1/2.75, as well as those from all other percentages of straw with a LR/G ratio of 1/3.25. On the other hand, the IB of panels containing more than 12.5% straw with LR/G ratios of 1/2.75 and 1/3.25 were lower than those of panels made from 0-12.5% straw also with both LR/G ratios. Panels consisting of 0%, 6.25% and 12.5% wheat straw with LR/G ratios of 1/2.75 and 1/3.25 met the minimum EN standard requirements of mechanical properties for general purposes. All of the panels containing 0-100% wheat straw with a LR/ G ratio of 1/2.75 or 1/3.25 met the required level of TS for 24-h immersion. 相似文献
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Morteza Asgarzadeh Kourosh Vahdati Mahmoud Lotfi Mostafa Arab Alireza Babaei Farzaneh Naderi Mohammad Pir Soufi Ghazaleh Rouhani 《Urban Forestry & Urban Greening》2014,13(3):450-458
Choosing appropriate plants for urban landscapes is vital to avoid potential financial and environmental losses that may occur if all selection parameters are not taken into account. A methodology has been developed to assist landscape architects, planting designers, and urban horticulturists in the plant selection process. Tehran has been picked as a case study due to its arid and semi-arid climate which poses more challenges in front of an expert. After grouping plants, selection parameters have been defined for each plant group. Plant species were comparatively graded for each parameter by a group of eight specialists. Analytical hierarchy process (AHP) technique and hierarchical cluster analysis have been utilized to find the most adaptable plant species for the area according to the main selection parameters of zone tolerance, urban conditions, esthetics, maintenance, growth characteristics, and specific features. Several new plants were ranked high in the final tables suggesting that the urban landscape of Tehran has a great potential to become more attractive, less allergic, and less costly, as well as consuming less water. Before introducing new plants to the urban environment, they should be experimented on in small numbers for several years to confirm that they will not change the ecology of the whole region through invasion or posing a threat to any local plant species. 相似文献
107.
The city of Tehran,like many polluted metropolises of the world,has higher emissions of greenhouse gases than other cities in Iran,due to heavy consumption of fossil fuel and landuse changes.To estimate carbon sequestration in two 40 year-old stands of planted Cupressus arizonica and Fraxinus rotundifolia in degraded lands surrounding Tehran,sampling of above-and below-ground biomass,soil(at two depths of 0-15 and 15-30 cm),and leaf litter was done by systematic random sampling.The total carbon stocks of C.arizonica and F.rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1.The aboveground biomass with 233.16(71%)Mg·ha-1 in C.arizonica and88.16(58.50%)Mg·ha-1 in F.rotundifolia contributed the most shares to carbon sequestration.The diameter at breast height,total height,basal area,total volume,and biomass of C.arizonica were significantly(p0.01)higher than those of F.rotundifolia.Also the depth of 0-30 cm of soil contributed between 18.29%and 32.15%of total ecosystem carbon,respectively.The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars,respectively.Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land,the current status quo.These stands can absorb atmospheric CO2 at different rates,thus tree species selection and stand development should be considered in planning future afforestation projects. 相似文献
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Mokhtari Morteza Sattaei Borzi N. Kargar Fozi M. Asadi Behzadi M. R. Bahreini 《Tropical animal health and production》2019,51(8):2203-2212
Tropical Animal Health and Production - In the present study, 10,116 body weight-age records were measured on 2537 Kermani lambs. The records were collected from Kermani Sheep Breeding Station,... 相似文献
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Nima Naderi Gholam R. Ghorbani Ali Sadeghi‐Sefidmazgi Shahryar Kargar Morteza Hosseini Ghaffari 《Journal of animal physiology and animal nutrition》2019,103(5):1351-1364
This study aims to evaluate the effects of substituting increasing concentrations of shredded beet pulp (SBP) for corn silage (CS) on nutrient intake, sorting index, intakes of particle size and nutrients, meal and rumination patterns, and chewing activity of dairy cows. Four multiparous (126 ± 13 day in milk) and 4 primiparous (121 ± 11 day in milk) Holstein cows were used in a 4 × 4 Latin square design experiment with 4 periods of 21 days. Dietary treatments were (DM basis): 16% of dietary DM as CS without SBP (0SBP); 8% CS and 8% SBP (8SBP); 4% CS and 12% SBP (12SBP); and 0% CS and 16% SBP (16SBP). We observed a reduction in the extent of sorting against long particles and medium particles but for fine particles with increasing SBP levels in the diets. The number of eating bouts per day was lesser (8.2%) in cows fed SBP diets compared with 0SBP cows and corresponded with a reduction in eating time per d across treatments. The number of ruminating bouts per day was similar across diets (16.8 bouts/day), but substituting SBP for CS in the diets tended to decrease linearly ruminating bout length (5 min/bout) and tended to increase ruminating bout interval (8 min/day). Eating, ruminating and total chewing time when expressed as minutes per kilogram of forage NDF intake and peNDF > 8 intake increased when SBP was substituted for CS in the diets. Primiparous cows had greater ruminating time (57 m/day) and total chewing time (73 min/day), eating rate (0.01 kg of DM/min) compared with multiparous cows. Also, increasing forage NDF and peNDF>8, >8‐mm DM intakes are effective means of stimulating ruminating and chewing activities. This study showed that SBP could partially replace CS and not affect DM intake, but chewing activity may decrease slightly. 相似文献
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Peyman Eynipour Morteza Chaji Mohsen Sari 《Journal of animal physiology and animal nutrition》2019,103(6):1708-1718
The aim of the experiment was to investigate the replacement value of common bean residues in the diet of finishing lambs as an inexpensive fodder instead of wheat straw or maize silage. Forty Arabi male lambs with average body weight of 18.90 ± 0.6 kg were randomly divided into five treatments with eight replications. The five experimental treatments consisted of control diet, and 50% and 100% replacement of bean residues with wheat straw or 25% and 50% replacement with maize silage in the control diet respectively. Lambs were slaughtered at the end of the experiment to evaluate carcass traits and meat characteristics. Dry matter intake, blood glucose, urea nitrogen, cholesterol and triglyceride concentration were not affected by the experimental treatments. Apparent digestibility of nutrients; total concentration of volatile fatty acids, acetate and butyrate; and total rumen protozoa population were linearly increased by increasing the levels of bean residues, as replacement with wheat straw (p < .05). Replacement of bean residues in control diets instead of wheat straw or maize silage caused a positive linear incremental trend for average daily gain and total weight gain. There was no significant difference in daily gain, final weight and feed conversion ratio among the treatments. Instead of wheat straw or maize silage, replacement bean residues linearly increased chewing, ruminating and eating activities per neutral detergent fibre intake (p < .05). Carcass traits and physicochemical characteristics of meat were not affected by the treatments. It is advisable to use bean residues in the diet of lambs as an alternative to the wheat straw or maize silage, because no adverse effects were observed on rumen fermentation, blood metabolites and performance; moreover, improvement in average daily gain, total weight gain and digestibility of nutrients, and the fact that bean residue is less expensive than wheat straw and maize silage. 相似文献