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11.
Assessment for salinity tolerance through intergeneric hybridisation: Triticum durum × Aegilops speltoides 总被引:1,自引:0,他引:1
Seyed Ahmad Sadat Noori 《Euphytica》2005,146(1-2):149-155
Summary Triploid hybrid embryos (AABB × SS = ABS) were produced by crossing two moderately salt-tolerant wheats, namely Triticum turgidum durum and Aegilops speltoides subsp. speltoides. The embryos were rescued by culturing on agar No. 1. Chromosome doubling was achieved by using 0.05% colchicine. The resulting
hexaploid plants grew to maturity, and produced a considerable amount of seed (≈40,000). The synthetic hexaploid (C2) was tested for salinity tolerance, grown at 0, 100, 125, 150, 160, 170, 180 and 200 mM NaCl in a standard nutrient solution
for 2 weeks. The criterion of salt tolerance was root growth in different NaCl concentrations. The amphidiploid material showed
greater salinity tolerance than either parent, suggesting the presence of different genes for tolerance in the parents. 相似文献
12.
Majid Aghaalikhani Majid Gholamhoseini Aria Dolatabadian Aydin Khodaei-Joghan Kamal Sadat Asilan 《Archives of Agronomy and Soil Science》2013,59(10):1149-1169
With regard to the low cation-exchange capacity and large saturated hydraulic conductivity of sandy soils, a field experiment was carried out in 2006–2007 to determine the impact of zeolite on nitrogen leaching and canola production. Four nitrogen (N) rates (0, 90, 180, and 270 kg ha–1) and three zeolite amounts (3, 6 and 9 t ha?1) were included as treatments. The results demonstrated that the highest growth parameters and seed yield were attained with 270 kg N ha?1 and 9 t zeolite ha?1. However, the highest and the lowest seed protein percentage and oil content were obtained with 270 kg N ha?1 accompanied by 9 t zeolite ha?1, respectively. Nitrate concentration in drained water was affected by nitrogen and zeolite. The lowest and highest leached nitrate values were found in control without N and zeolite (N0Z0) and in treatments with the highest N supply without zeolite (N270Z0), respectively. In general, nitrogen-use efficiency decreased with an increase in N supply. Application of 9 t zeolite ha?1 showed higher nitrogen use efficiency than other zeolite amounts. Also, application of more N fertilizer in soil reduced nitrogen uptake efficiency. In total, application of 270 kg N ha?1 and 9 t zeolite ha?1 could be suggested as superior treatment. 相似文献
13.
Elham Sadat Yazdi Almodarresi Javad Mokhtari Seyed Mohammad Taghi Almodarresi Mahdi Nouri Ali Shams Nateri 《Fibers and Polymers》2013,14(7):1196-1202
Conventional theory for color matching is Kubelka-Munk, but it fails in some situations. New intelligent procedures such as neural networks could learn the behavior of a complex system and produce accurate prediction. This paper investigates the ability of MLP (multiple layer perceptron) neural network for color matching of cotton fabric. Three reactive dyes, namely Levafix Red CA, Levafix Yellow CA and Levafix Blue CA were used for experiments. The dyed samples were scanned and L * a * b * histogram were extracted. Different neural networks were trained and tested using L * a * b * histogram of fabric’s images and also L * a * b * values (D65, 10°) of fabrics. The results were encouraging. For neural networks including the L * a * b * histogram in input vector, colorants and their concentration were predicted with a mean square error (MSE) less than 10?5 and an average value of color difference (CMC (1:2)) less than 1.5 for approximately 80 % of testing data. 相似文献
14.
15.
Mahbube Sadat Musavi Jad Seyed Abdolkarim Hosseini Ravandi Hossein Tavanai Razieh Hashemi Sanatgar 《Fibers and Polymers》2011,12(6):801-807
The aim of this paper is to investigate vertical wicking in polyacrylonitrile (PAN) electrospinning nanofiber yarn using image
analysis. Colored liquid rising phenomenon into the yarn and the distance of liquid rise were determined as a function of
time. The kinetics of capillary rise follows the Lucas-Washburn equation. The results show that capillary rise rate coefficient
is being reduced with increasing yarn twist, due to the reduction of continuity and size of capillaries. Increasing heat treatment
stretch from 0 % (draw ratio=1) to 50 % (draw ratio=1.5) increases the capillary rise rate coefficient, due to the more homogeneity
of capillary spaces in the yarn structure and increasing heat treatment stretch from 50 to 100 % (draw ratio=2) reduces capillary
rise rate coefficient, because of the low capillary length. The present study indicates that an appropriate choice in production
parameters of nanofiber yarn is all important in obtaining the desired properties of capillary rise. 相似文献
16.
Toktam Taghavi Adam Dale James Luby James Hancock Becky Hughes 《International Journal of Fruit Science》2016,16(4):258-266
ABSTRACTCommon strawberry cultivars are hermaphrodites, producing both anthers and pistils in their flowers. However, octoploid Fragaria species are trioecious and different genotypes can be female with pistillate flowers, hermaphrodites, or males with staminate flowers. One female selection, F. virginiana High Falls 22 and three hermaphrodite selections, N8688, RH23, and Montreal River 10 were hybridized with five June-bearing cultivars. Seedlings of each family were planted in Ontario and Michigan. Two F. chiloensis selections Pigeon Point (female) and FRA1267 (hermaphrodite), were hybridized with 14 F. virginiana selections. Seedlings from each family were planted in Ontario and Minnesota. In all progeny, the presence or absence of anthers was recorded and a subjective scale used to estimate the percentage of fruit set (1–10 representing 10% intervals). Also, FRA1267 was crossed with one F. × ananassa selection and the progeny intercrossed and grown in Ontario. In the sib-crosses gender was recorded. In two female parents, the female progeny had on average a higher fruit set than the hermaphrodite progeny. F. virginiana genotypes varied in their fruit set, which suggested that there are a number of alleles involved in the fertility of hermaphrodites. In crosses, FRA1267 produced 80% females when used as a female parent and 100% hermaphrodites when used as a male parent. It is thought that the trait is inherited cytoplasmically or that the F. chiloensis alleles involved are epistatic when F. virginiana or F. × ananassa is used as a male parent. 相似文献
17.
Variability in response to salinity was examined in 29 Triticum durum Desf. accessions or cultivars based upon relative root and shoot lengths of 14-day-old seedlings grown in control and 100 mM NaCl solutions. NaCl caused a significant reduction of root and shoot growth for all accessions/cultivars, but the degree of reduction differed between them. Some cultivars had significantly greater relative root and shoot lengths than others, suggesting that there may be potentially useful variability in salinity tolerance within the durum wheats. 相似文献
18.
BACKGROUND: The p53 protein function is essential for the maintenance of the nontumorigenic cell phenotype. Pancreatic tumor cells show a very high frequency of p53 mutation. To determine if restoration of wild type p53 function can be used to eliminate the tumorigenic phenotype in these cells, pancreatic tumor cell lines, PANC-1 and HTB80, differing in p53 status were stably transfected with exogenous wild type p53 gene. METHODS: The transfection was performed using Polybrene/DMSO-Assisted Gene Transfer method. The wild type p53 gene integration into genomic DNA was detected by Southern blot and PCR. Furthermore, the expression of wild type p53 protein was detected in selected clones by immunohistochemistry and Western blot. RESULTS: While HTB80 cell line failed to produce a stable p53 expressing clone, the PANC-1 cells produced stable lines. Following characterization of clones, the growth rate and tumorigenicity of PANC-1 wild type p53 clones were compared to the control cells. Our data showed that the expression of wild type p53 decreased the growth rate of PANC-1 cells. It was also observed that the expression of wild type p53 in PANC-1 cells suppressed its potential for tumor formation in nude mice, completely, while the parental line leads to the formation of a relatively large tumor. CONCLUSION: Our results suggest that gene therapy based on restoration of wild type p53 protein function in pancreatic tumor cells with high amount of mutant p53 is a feasible option in pancreatic cancer treatment. 相似文献
19.
Sana Eybpoosh Yeganeh Talebkhan Samaneh Saberi Maryam Esmaeili Akbar Oghalaie Fatemeh Ebrahimzadeh Toktam Karimi Afshin Abdirad Azin Nahvijou Mohammad Ali Mohagheghi Mahmoud Eshagh Hosseini Marjan Mohammadi 《Iranian Biomedical Journal》2015,19(3):133-142
Background:
Serologic screening of gastric cancer (GC) by serum pepsinogens (sPG) levels and Helicobacter pylori (Hp) sero-status, though highly informative, has provided heterogeneous results. Here, we have evaluated the modifying effects of demographic factors on the risk impact of Hp sero-status/sPG levels in gastric cancer, with particular emphasis on age.Methods:
A cross-sectional study was carried out on 1341 individuals (GC = 578, healthy = 763), who were stratified into two age groups: 35-59 years (middle-aged, n = 830) and ≥ 60 years (60 years-plus, n = 511). Demographic factors and serological states (Hp sero-staus and sPG levels) were recorded by subject interview and serum ELISAs, respectively. Covariate-specific odds ratios were calculated by multivariable logistic regression.Results:
Hp infection was consistently associated with increased sPGI and sPGII levels in the 60 year-plus, but not the middle-aged group. The joint examination of the variable states of the three serum biomarkers (Hp serology, sPGI, and sPGI/II ratio), in the 60 year-plus age group, demonstrated a stepwise escalation of risk from the single (sPGIlow; OR = 2.6), to double (sPGIlow/sPGI/IIlow; OR = 3.55, and Hppositive/sPGIlow; OR = 5.0) and ultimately triple (Hppositive/PGIlow/PGI/IIlow; OR = 10.48) positive states, in reference to the triple negatives. However, this pattern was not exhibited in the middle-aged subjects.Conclusion:
Age was clearly identified as a modifying factor on the risk projection of the combined states of Hp serology and sPG levels in gastric cancer screening, reflected by the augmented (~10.5 fold) risk of GC in the triple positive (Hppositive/sPGIlow/sPGI/IIlow) 60 year-plus subjects, which was not evident in the middle-aged group. Key Words: Biomarkers, Demography, Age Distribution 相似文献20.
Multilocus sequence analysis reveals a novel phylogroup of Xanthomonas euvesicatoria pv. perforans causing bacterial spot of tomato in Iran
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A multilocus sequence analysis (MLSA) was performed on five housekeeping genes (fusA, gapA, gltA, lacF and lepA) of 22 Xanthomonas euvesicatoria strains recently isolated from alfalfa, pepper and tomato plants in Iran. In addition, 161 strains isolated worldwide from pepper, poinsettia, rose and tomato plants were included in the analysis. All X. euvesicatoria pv. perforans isolates from tomato plants in Iran clustered in a monophyletic group, although five MLSA haplotypes were detected among them. The Iranian tomato strains presented 10 nucleotide differences in the lepA gene sequences compared to the known worldwide population of X. euvesicatoria pv. perforans. Statistical analyses revealed a recombination event that had occurred in the lepA gene of the strains isolated from tomato in Iran. BOX‐PCR analysis confirmed the inclusion of Iranian tomato strains within X. euvesicatoria pv. perforans. Furthermore, X. euvesicatoria pv. euvesicatoria strains isolated from pepper in Iran differed in one nucleotide in the lepA gene sequence from the known worldwide population of the pathovar, and clustered in a group containing strains isolated in Nigeria. The strains isolated from alfalfa in Iran clustered with the type strain of X. euvesicatoria pv. alfalfae. Altogether, the results reveal the existence of a phylogenetically novel population of X. euvesicatoria pv. perforans in Iran which needs further in‐depth analysis to pinpoint the epidemiological impact of these strains. 相似文献