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Apple breeding is usually done to produce higher quality apples. We crossed two late ripening high quality apple cultivars (i.e., Golden Smoothie and Red Spur) as maternal parents with two Iranian domestic early ripening apple cultivars (i.e., Golab-e Kohanz and Shafi Abadi) as pollen parents in 2005 to breed new early ripening apple cultivars. We then measured qualitative and quantitative traits of 360 off spring during 2010 and 2011. Results of recorded traits on the 5th and 6th year of growth of the progeny showed that during two evaluation years, flowering and fruit ripening time, titrable acidity, SSC/acid ratio, and fruit weight had the highest coefficients of phenotypic variations. Progenies were classified in three groups: early, mid, and late ripening. Some of the selected progeny were better than their early ripening parental cultivars being earlier in the ripening, with larger fruit size and better texture and flavor. Genotypes A31, A32, I5, I23, and I57 were in the early ripening category, B11 and A34 were in the middle, and B77 and E21 were in the late ripening categories. These characteristics were considered to present an improvement.  相似文献   
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Knowledge of relationships among the cultivated and wild species of Cerasus, a subgenus of Prunus L., is important for recognizing gene pools, identifying pitfalls in germplasm collections and developing effective conservation and management strategies. In this study, morphological characterization of wild Cerasus subgenus species naturally growing in Iran, including P. avium L. (mazzard), P. mahaleb L., P. brachypetala Boiss., P. incana Pall., P. yazdiana Mozaff., P. microcarpa Boiss. subsp. microcarpa, P. microcarpa Boiss. subsp. diffusa and P. pseudoprostrata Pojark. and three commercial species, sweet cherry (P. avium L.), sour cherry (P. cerasus L.) and duke cherry (P. × gondouinii Rehd.) was investigated. Twenty-nine variables were recorded in 95 accessions of these species to detect similarities among them. All studied characteristics were showing a high degree of variability, but it was highly pronounced for plant height, leaf characters especially for dimensions and pubescence as well as for petiole and peduncle length. The majority of significant correlation coefficients were found in the characteristics representing plant size and growth habit with leaf size. Principal component analysis was performed for phenotypical diversity determination and grouping of species. Characters with high discriminating values were those related to growth habit, height, compactness, trunk diameter, leaf dimensions, petiole length, leaf tip and serration, flower color, peduncle length, fruit shape and stone shape. Based on the cluster analysis, species included in two main clusters, first those with large structure (sweet, sour and duke cherries, mazzard and mahaleb), second the other species with small structure which might be potentially suitable for rootstock breeding programs. Scatter plot using two first factors also confirmed the grouping by cluster analysis. The conservation of the highly diverse native populations of Iranian wild Cerasus species is recommended.  相似文献   
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High levels of guanidinoacetate acid (GAA) deteriorate growth response in broiler chickens. We propose using coenzyme Q10, an antioxidant, and taurine (TAU), a methyl donor, to cope with the situation when high level of GAA included in diet. GAA was supplemented at 0 (control), 0.75, 1.5 and 2.25 g/kg in isoenergetic and isonitrogenous diets and fed to broilers (Cobb 500) from 1 to 40 days post‐hatch. Three additional diets were prepared by adding CoQ10 (40 mg/kg), TAU (40 mg/kg) or their combination (both CoQ10 and TAU at 40 mg/kg) to the 2.25 g/kg GAA group. The experimental design used was a completely randomized design. While weight gain (p = 0.038) and feed conversion ratio (p = 0.024) improved when GAA added at 1.5 g/kg, higher supplementation (2.25 g/kg) deteriorated these responses. These responses, however, were significantly restored by using CoQ10, TAU or their combination. Abdominal fat deposition was significantly decreased when TAU added to broiler diets by virtue of upregulating peroxisome proliferator‐activated receptor alpha. Supplementing broiler diets with CoQ10 and TAU or their combination significantly decrease ascites mortality. In conclusion, CoQ10 and TAU have shown beneficial effects when high level of GAA included in broiler diets.  相似文献   
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The aim of this study was to investigate the cytotoxic and anticancer activities of stylosin, a monoterpene extracted from an edible plant, Ferula ovina, on 5637 and HFF3 cells using MTT and comet assays and DAPI staining.To assess stylosin effects, cells were cultured in the presence of various concentrations of stylosin during three days; the IC50 of stylosin on cancerous 5637 cells was less than its value on HFF3 normal cells, indicating that it might have anticancer properties. Investigating the mechanism of stylosin action revealed that it quickly induced DNA lesions and increased the number of apoptotic cells.  相似文献   
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A new analytical method (liquid chromatography-antioxidant, LC-AOx) was used that is intended to separate beer polyphenols and to determine the potential antioxidant activity of these constituents after they were allowed to react online with a buffered solution of the radical cation 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(?+)). Using the LC-AOx method, it was possible to demonstrate that the extent of the antioxidant activity was very much dependent on the phenolic compound considered. The method was also applied to the analysis of beer extracts and allowed the evaluation of their antioxidant activity at different steps of beer processing: brewing, boiling, and fermentation. This study showed that the total antioxidant activity remained unchanged throughout beer processing, as opposed to the polyphenolic content, which showed a 3-fold increase. Hopping and fermentation steps were the main causes of this increase. However, the increase measured after fermentation was attributed to a better extraction of polyphenols due to the presence of ethanol, rather than to a real increase in their content. Moreover, this method allowed the detection of three unknown antioxidant compounds, which accounted for 64 ± 4% of the total antioxidant activity of beer and were individually more efficient than caffeic acid and epicatechin.  相似文献   
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There is a high diversity among cultivated walnut trees in Iran due to its long time of seed propagation and vast area of cultivation. In this study some morphological characters as well as Simple Sequence Repeat (SSRs) markers were used to analyze the genetic diversity and relationships among 31 Iranian walnut genotypes along with four foreign cultivars. The nut weight ranged from 7.52 to 17.73 g, kernel weight from 4.00 to 9.83 g, and kernel percentage ratio from 38.78 to 67.05% among studied genotypes. In SSRs analysis, nine primer pairs were tested that produced 39 alleles ranging from 2 to 8, with a mean value of 5.10 allele per primer. The Iranian genotypes showed relatively high diversity both for their SSRs loci and morphological traits. Although the foreign cultivars (‘Serr’, ‘Vina’, ‘Franquette’ and ‘Lara’) clustered with each other, they also laid close and within the Iranian genotype. The results of the study provided us with valuable diversity among our genotypes which could be used for breeding studies and also showed the power of genetic markers for analysis and evaluation of this diversity.  相似文献   
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In order to shed light on the role of Iran in apple evolution and domestication, we chose to investigate the relationships of a collection of 159 accessions of wild and domesticated apples including Iranian indigenous apple cultivars and landraces, selected wild species, and old apple scion and rootstock cultivars from different parts of the world. The majority of the wild species belonged to M. sieversii, which is widely believed to be the main maternal wild ancestor of domestic apples, from Kazakhstan and M. orientalis, which is one of the probable minor ancestors of domestic apples, from Turkey and Russia located on the east and west of Iran, respectively. The accessions were assigned into six arbitrary populations for the purpose of generating information on genetic parameters. Nine simple sequence repeat (SSR) loci selected from previous studies in apple were screened over DNA extracted from all the accessions. Results showed that all SSR loci displayed a very high degree of polymorphism with 11–25 alleles per locus. In total, there were 153 alleles across all loci with an average of 17 alleles per locus. The SSR allelic data were then used for estimation of population genetic parameters, including genetic variation statistics, F-statistics, gene flow, genetic identity, genetic distance and then cluster analysis using POPGENE 1.32 software. The F-statistics and gene flow in particular, showed that there was more intra-population than between population variation. The genetic identity and genetic distance estimates, and the dendrogram generated from the un-weighted pair group arithmetic average (UPGMA) method of cluster analysis showed that the Iranian cultivars and landraces were more closely related to M. sieversii from Central Asia (east of Iran) and M. orientalis native to Turkey and Russia than to other accessions of Malus species. Also, the old apple cultivars from different parts of the world have a closer genetic relationship to M. sieversii, M. orientalis and the Iranian apples, than to other wild species. Based on these results, we suggest that the Iranian apples may occupy an intermediate position between the domesticated varieties and wild species. We propose that Iran could be one of the major players in apples’ domestication and transfer from Central Asia to the western countries.  相似文献   
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