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11.
Chemical composition and antioxidant activity of four fennel populations (England, Spain, Poland and Iran) were investigated during six developmental stages including two vegetative and four reproductive phases. In reproductive phase, the essential oil content of fruits decreased and the maximum content (5.9%) was obtained in immediate fruits. The essential oils were analyzed using GC/MS. trans‐Anethole was the main component of the leaves and the fruits oil. In leaves, it ranged from 41.28% in England at late vegetative stage to 56.6% in Poland population at early vegetative stage. Other major compounds of leaves were limonene, α‐pinene and (Z)‐β‐ocimene. In reproductive phases the trans‐anethole increased dramatically. It varied from 85.25% in immature fruits from Poland to 90.7% in pre‐mature stage from Spain. The highest phenolic content in the extracts at different growth stages obtained 189 mg TAE/g DW at full mature stage of seed in Iran population. The flavonoid of leaves extract ranged from 3 to 7.5 mg QUE/g DW, while in fruits extract varied from 3 to 10.3 mg QUE/g DW. Antioxidant activity of the extracts was evaluated using 1,1‐diphenyl‐2‐picrylhydrazy (DPPH) and β‐carotene model systems. Immature and full mature growth stages of fennel population from Spain indicated the highest activity in quenching of DPPH radical (74.2% and 74.5, respectively). Antioxidant activities of the extracts had high positive correlation with their phenolic contents in all fruit maturity stages. Finally, it might probably be suggested that in fennel the hot and humid condition can lead to increase trans‐anethole, while the hot and dry one can produce higher amount of phenolics and flavonoids.  相似文献   
12.
Cytological analyses were performed in nineteen accessions belonging to seven Achillea species. The results indicate that two species, A. filipendulina and A. tenuifolia, are diploid (2n = 2x = 18) and three species, A. bieberstinii, A. pachycephala, and A. aucheri are tetraploid (2n = 4x = 36). For two latter species, the chromosome numbers are new. Two ploidy levels of 2n = 6x = 54 and 2n = 8x = 72 in A. millefolium and two ploidy levels of 2n = 2x = 18 and 2n = 4x = 36 in A. santolina species were found. Cluster analysis based on chromosomal characteristics and karyotype asymmetry indices clustered the studied genotypes into three major groups. The first group included the diploid species (A. filipendulina, A. santolina and A. tenufolia), while the second group comprised tetraploid species (A. santolina, A. aucheri and A. pachycephala). A. millefolium (hexaploid, octaploid) and A. bieberstinii (tetraploid) were classified in the third group. Total form percentage (TF%) in groups 1, 2 and 3 were 42.03, 42.15 and 41.08, respectively. Group 1 possessed the highest average of symmetry index (S% = 70.8). Stebbins classification method grouped all accessions in class A. Moreover, group 1 (diploid level species), had the most symmetric karyotype from point of view of centromere and chromosome length. Therefore, it can be concluded that the genotypes belonging to group 1 are the earliest evolutionary form.  相似文献   
13.
Due to precise evaluation of genetic diversity of Carthamus species, sixty-two genotypes consisting fifty-two from five wild (C. oxyacanthus M. Bieb, C. lanatus L., C. dentatus Vahl, C. boissieri Halácsy, C. glaucus M.B.) and ten from cultivated species (C. tinctorius L.) were selected for evaluation of the genetic diversity in Carthamus species. A total of 238 (81.2 %) polymorphic bands were detected by 12 SRAP primer combinations with an average of 22 bands per combination. Me4-Em1 and Me5-Em2 primer combinations were known as the most informative SRAP markers based on the PIC values (0.34) where they distinguished all studied Carthamus species. Cluster analysis classified all accessions into five main groups among which clusters containing cultivated individuals were distinctly separated from those containing wilds. The most and the least genetic variation based on analysis of molecular variance, were detected within (76.90 %) and among (22.84 %) groups, respectively. The obtained results suggested that C. dentatus, C. glaucus and C. boissieri species may be classified in one section including C. dentatus in one and C. glaucus and C. boissieri in another subsection. The results also revealed high genetic similarity between C. oxyacanthus and C. tinctorius despite their different morphological characteristics.  相似文献   
14.
Yarrow (Achillea millefoilum L.) is an important medicinal plant with different medicinal and ornamental uses. In this study, SSR markers were developed for the first time from the genome A. millefolium using the slightly modified Hamilton protocol. Three yarrow genomic libraries were constructed, enriched for microsatellite motifs AG, AC and ATG. A total of 30 primer pairs were developed of which 16 were polymorphic in 26 A. millefolium accessions. One accession from A. tenuifolia species was also included to assess the transferability of new developed SSR primers in other species. The average allele number of SSR markers was 8.5 per locus and ranged from 2 to 14. The observed heterozygosity (H O) varied from 0 to 0.96 with an average of 0.52 and the expected heterozygosity (H E) ranged from 0.07 to 0.49 with an average of 0.39. Among primers, Am142 showed the highest polymorphic information content (PIC) and the lowest value was obtained from Am59 primer with an average of 0.33. Three loci (AmK59, AmK344 and AmK329) deviated significantly from Hardy-Wrinberg Equlibrium (HWE) and one locus (Am344) might have null alleles. Cluster and PCoA analyses classified A. millefolium accessions according to their geographical distribution and A. tenuifolia species completely separated from A. millefoliulm genotypes.  相似文献   
15.
Essential oil (EO) composition, phenolic content, and antioxidant activity were investigated in 17 P. abrotanoides populations collected from different geographical regions in Iran. The highest (3.61%) and lowest (1.25%) essential oil yields were measured in populations from Semnan Province (PSESM2) and PISKS from Isfahan Province, respectively. GC/MS analysis identified camphor (4.05 – 35.94%), 1,8‐cineole (7.15 – 24.34%), borneol (0 – 21.75%), and α‐pinene (2.05 – 10.33%) as the main constituents of Perovskia essential oil. Cluster analysis classified the studied populations into four different groups: (I) high camphene, (II) high camphor/1,8‐cineole, (III) high borneol/δ‐3‐carene, and (IV) high α‐cadinol/trans‐caryophyllene. The highest flavonoid and phenolic contents were detected in PISAK from Isfahan Province (4.09 ± 0.05 mgQE/gDW, 58.51 ± 1.63 mgGAE/gDW) and PKRGS from Khorasan Province (3.80 ± 0.002 mgQE/gDW, 66.86 ± 0.002 mgGAE/gDW). DPPH and reducing power activity model systems identified PMASA and PKRKL as the populations with the highest antioxidant activity. Finally, the data obtained represented valuable information for introducing elite populations with EO components favorable to pharmaceutical and industrial applications.  相似文献   
16.
Thymus daenensis is an aromatic medicinal plant endemic to Iran. We used inter simple sequence repeat (ISSR) markers to detect genetic polymorphism in this herb using 17 T. daenensis accessions collected from different geographic regions in Iran. The 15 primers chosen for analysis revealed 256 bands, of which 228 (88.9%) were polymorphic. Jaccard’s similarity indices based on ISSR profiles were subjected to UPGMA cluster analysis. The generated dendrogram revealed two major groups. The Tc group included the accessions collected from the center of the Zagros Mountains, and the Te group was collected from the extremes of the Zagros range. A principal coordinate analysis confirmed the results of clustering. The results showed that the divergence of accessions based on the Zagros Mountains is more logical in comparison with classification on the basis of provincial borders. Gene diversity and expected heterozygosity were greater in the Tc group than in the Te group, suggesting that the germplasm collected from the center of the Zagros Mountains is more variable.  相似文献   
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