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1.
Amplified fragment length polymorphism (AFLP) analysis is a rapid and efficient method for producing DNA fingerprints and molecular characterization. Our objectives were to: estimate genetic similarities (GS), marker indices, and polymorphic information contents (PICs) for AFLP markers in almond cultivars; assess the genetic diversity of almond cultivars and wild species, using GS estimated from AFLP fingerprints and molecular characterization; and facilitate the use of markers in inter-specific introgression and cultivar improvement. The genetic diversity of 45 almond cultivars from Iran, Europe, and America, were studied assaying 19 primer combinations. In addition, several agronomic traits were evaluated, including flowering and maturity times, self-incompatibility, and kernel and fruit properties. Out of the 813 polymerase chain reaction fragments that were scored, 781 (96.23%) were polymorphic. GS ranged from 0.5 to 0.96, marker indices ranged from 51.37 to 78.79, and PICs ranged from 0.56 to 0.86. Results allowed the unique molecular identification of all assayed genotypes. However, the correlation between genetic similarity clustering as based on AFLP and clustering for agronomic traits was low. Cluster analysis based on AFLP data clearly differentiated the genotypes and wild species according to their origin and pedigree, whereas, cluster analysis based on agronomic data differentiated according the pomological characterization. Our results showed the great genetic diversity of the almond cultivars and their interest for almond breeding.  相似文献   
2.
The ability of hexaconazole (HEX) to ameliorate salinity stress was studied in canola plants (Brassica napus L.). Canola seedlings were subjected to sodium chloride (NaCl) treatment. A treatment with 200 mM NaCl reduced growth parameters, chlorophyll content and protein content as well as increased the proline (Pro) content in canola plants. In addition, NaCl stress increased the endogenous, nonenzymatic antioxidants and the activity of antioxidant enzymes, such as peroxidase (POX; EC 1.11.1.7), superoxide dismutase (SOD; EC 1.15.1.1) and catalase (CAT; EC 1.11.1.6). When these plants were treated with a combination of NaCl and 50 mg L−1 HEX, the inhibitory effects of NaCl stress were decreased by increasing the root growth, shoot growth, dry weight (DW), chlorophyll content, protein content and antioxidant enzyme activity by ameliorating the salinity injury. These results suggested that HEX has an important role in the enhancement of plant antioxidant systems and resistance to salinity in canola plants.  相似文献   
3.
In 12th century, the Buddhist priest Eisai brought tea ( Camellia sinensis L.) seeds to Japan from China and now tea plants are cultivated all over Japan except in the Hokkaido and Tohoku districts. The quality (reflected in the price) of Japanese green tea is affected by the nitrogen content. Consequently in tea fields, for last three decades large amounts of fertilizer have been applied to produce high quality tea. As a result, problems such as acidification of soil have been caused. It is also known that the growth of tea plants is stimulated by the addition of aluminum (Al) under acidic conditions. In this keynote address, some problems caused by excess applications of fertilizer in tea fields and the growth characteristics of tea plants related to Al are presented.  相似文献   
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5.
PCR-RFLP analyses of three regions for each of chloroplast DNA (cpDNA; rbcL-ORF106, trnD-trnT, trnH-trnK) and mitochondrial DNA (mtDNA; nad7/exon2-exon3, nad7/exon3-exon4, 18S-5S) were performed in 26 cultivars of acid citrus grown in Japan to identify polymorphisms and classify them. The polymorphisms were compared with those of three true Citrus species, i.e., mandarin, pummelo and citron. Ichang papeda (C. ichangensis) was also included in this study to find its relationship with Yuzu. Inter-species cpDNA variation was recognized and the acid citrus were divided into three groups, namely; I (‘Yuzukichi’ and ‘Kinkoyu’), II [sour oranges (‘Kaiseito’, ‘Daidai’ and ‘China daidai’), ‘Nansho daidai’, ‘Kiku daidai’, C. sudachi (‘Mushi yukaku’, ‘Yushi yukaku’ and ‘Yushi mukaku’), C. sphaerocarpa (‘Kabosu’ and ‘Aka kabosu’), C. kizu (‘Taninaka kizu’, ‘Kinosu’ and ‘Kizu’), ‘Zanbo’, ‘Mochiyu’, ‘Jabara’ and ‘Naoshichi’], and III [Yuzu (‘Tetraploid’, ‘Tochikei yuzu’ and ‘Yamanekei yuzu’), ‘Matsuda sudachi’, ‘Zuishoyu’, ‘Hanayu’ and ‘Yuko’]. CpDNA restriction patterns of the three true Citrus species differed from each other as well as from those of ichang papeda. CpDNA restriction patterns of group I of the acid citrus were identical to those of mandarins. Group II showed the same as pummelos. CpDNA restriction patterns of group III were differed from those of the three true Citrus species in the three regions. This group was differed from ichang papeda after digestion of trnH-trnK PCR products with TaqI, HinfI and AluI, while they showed identical restriction patterns in two regions, rbcL-ORF106 and trnD-trnT. Citrons and ichang papeda were placed in groups IV and V, respectively. Based on mtDNA restriction patterns, the acid citrus were divided into three groups; i, ii and iii. In groups i and ii accessions of groups I and II of cpDNA were placed with mandarins and pummelos, respectively. In group iii accessions of group III of cpDNA were placed with ichang papeda. Citrons were placed in a distinct group, iv.  相似文献   
6.

This study used pedigree information and data collected from 1979 to 2012 at the Raeini Cashmere goat breeding station, located in Baft City in Kerman Province in southeastern Iran. Genetic and phenotypic parameters for early reproductive traits of breeding does, including total numbers of kids born at first kidding (LSB1), total numbers of kids weaned at first kidding (LSW1), total birth weight of all kids born at first kidding (LWB1), total weaning weight of all kids weaned at first kidding (LWW1), and age at first kidding (AFK), were estimated using a Bayesian approach via Gibbs sampling. Posterior means for heritability estimates of LSB1, LSW1, LWB1, LWW1, and AFK were statistically significant, with values of 0.12, 0.23, 0.17, 0.15, and 0.46, respectively. Low-to-moderate additive genetic variation was present for the studied reproductive traits. Estimated genetic correlations among LSB1, LSW1, LWB1, and LWW1 were statistically significant and ranged from 0.12 between LWB1 and LWW1 to 0.72 between LSB1 and LSW1. Corresponding phenotypic correlation estimates were also statistically significant and ranged from 0.04 between LWB1 and LWW1 to 0.55 between LSB1 and LSW1. Posterior means of genetic and phenotypic correlations between AFK and other studied traits were statistically significant only for LSB1 and LWB1. For LSB1, LSW1, LWB1, and LWW1, we conclude that genetic and phenotypic improvement in any of these traits in Raeini Cashmere does would favorably influence all of the other traits. However, does that first kidded at younger ages have smaller litters at birth and lower litter birth weights at their first parity.

  相似文献   
7.
BACKGROUND: Serum biochemical and hematologic parameters are important in the management of game species in Iran, such as Persian squirrels. OBJECTIVE: The purpose of this study was to establish baseline serum chemistry and hematology values in Persian squirrels (Sciurus anomalus) and describe blood cell morphology and the electrophoretic pattern of hemoglobin. METHODS: Blood samples were collected from 30 Persian squirrels (Sciurus anomalus) maintained in captivity in the Tehran Zoo. Blood was placed into EDTA and serum clot tubes and analyzed using standard manual hematology and biochemical techniques. Hemoglobin electrophoresis was done on cellulose acetate paper strips. RESULTS: Minimum, maximum, and median values were obtained for 11 hematologic and 12 serum chemistry parameters. Hypersegmented neutrophils were observed frequently. We did not find basophils or band neutrophils. Hemoglobin electophoresis resulted in a band slightly anodal to that of human hemoglobin A. CONCLUSION: Biochemical and hematologic values in Persian squirrels were comparable to those of related species, and may be used as a standard profile for healthy Persian squirrels kept in captivity.  相似文献   
8.
A novel biodegradable polylactic acid-based polyurethane (PU) was synthesized via a chain extension reaction between hydroxylated polylactic acid (PLA-OH) and hydroxylated tung oil (HTO) using 1,6-hexamethylene diisocyanate (HDI) to link the two polyols and dibutyltin dilaurate (DBTDL) as a catalyst. Both PLA-OH and HTO, as polyols, were separately synthesized in our laboratory. Three different molecular weights of PLA-OH prepolymers were used, and the molar ratio of PLA-OH to HTO was also changed to investigate the effect of these two parameters on the structure and properties of the final PUs. Chemical structures of PLA-OH, HTO, and final PUs were investigated by Fourier transform infrared (FTIR) and Hydrogen-1 nuclear magnetic resonance (1HNMR) spectroscopies. Thermal transitions and thermal stability of the final PUs were, respectively, studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The FTIR and 1HNMR results showed that the chain-extension reaction of the two polyols with HDI was sufficiently achieved. The TGA results showed that the polyurethanes based on the lower molecular weight PLA segments were more thermally stable; it was not degraded up to 270 °C. DSC results showed that incorporating HTO in the PU chains led to formation of more flexible PU chains, while the glass transition temperatures of the PUs of higher PLA-OH molecular weights were higher than those of lower ones.  相似文献   
9.

Background:

Skin flap grafting is a popular approach for reconstruction of critical skin and underlying soft tissue injuries. In a previous study, we demonstrated the beneficial effects of two 5α-reductase inhibitors, azelaic acid and finasteride, on tissue survival in a rat model of skin flap grafting. In the current study, we investigated the involvement of nitric oxide and inducible nitric oxide synthase (iNOS) in graft survival mediated by these agents.

Methods:

A number of 42 male rats were randomly allocated into six groups: 1, normal saline topical application; 2, azelaic acid (100 mg/flap); 3, finasteride (1 mg/flap); 4, injection of L-NG-nitroarginine methyl ester (L-NAME) (i.p., 20 mg/kg); 5, L-NAME (20 mg/kg, i.p.) + azelaic acid (100 mg/flap, topical); 6, L-NAME (20 mg/kg, i.p.) + finasteride (1 mg/flap, topical). Tissue survival, level of nitric oxide, and iNOS expression in groups were measured.

Results:

Our data revealed that azelaic acid and finasteride significantly increased the expression of iNOS protein and nitric oxide (NO) levels in graft tissue (P < 0.05). These increases in iNOS expression and NO level were associated with higher survival of the graft tissue.

Conclusion:

It appears that alterations of the NO metabolism are implicated in the azelaic acid- and finasteride-mediated survival of the skin flaps.Key Words: Finasteride, Azelaic acid, Surgical flaps, Nitric oxide, Nitric oxide synthase Type II  相似文献   
10.
A total of 137 accessions from 18 wild almond species were collected from Iran and leaf and fruit traits were characterized. Also evaluated were flowering and ripening date, self-incompatibility and kernel bitterness. An extensive phenotypic diversity was found both among and within species. Differences in average leaf dimensions among and within species were associated with average rainfall but not altitude of collection site. Adjacent accessions located in drier areas had smaller leaf dimensions than those located in semi-humid or humid regions. No relation was found between average fruit dimensions and collection site conditions. Principal component analysis revealed that the nut weight and width, and the kernel weight had highest loading in the first component accounting for 45.8% of total variation. In contrast, leaf traits in the second component accounted for 22.3% of total variation. No significant correlations were detected between leaf dimensions and fruit traits in all species evaluated. Results document a rich source of new germplasm for almond improvement programs. Small fruit size, pollen-pistil self-incompatibility, and bitter kernel flavour are the most common obstacles to the utilization of this wild germplasm in breeding.  相似文献   
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