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This study investigated the effect of drought stress on the amount of phenolic and flavonoid compounds as well as H 2 O 2 and malondialdehyde (MDA) in Achillea pachycephala. The expression patterns of the key genes and their molecular mechanisms in the phenylpropanoid pathway (PAL , CHS , CHI , F3H , F3′H , F3′5′H , FLS) were also assessed during drought stress using quantitative real-time polymerase chain reaction (qRT-PCR). The samples were harvested at 0, 7, 14, 21 and 28 days after exposure to drought stress. High-performance liquid chromatography (HPLC) analysis was performed to determine the changes of phenolic and flavonoid compounds – chlorogenic acid, caffeic acid, rutin, luteolin-7-O-glycoside, 1,3-dicaffeoylquinic acid, apigenin-7-O-glycoside, luteolin, apigenin and kaempferol – during stress conditions. Concentrations of most of the compounds increased with increasing drought stress duration. Most of the phenolic acids continued to accumulate with increasing duration of stress, while flavonoids dramatically decreased at day 28 of stress. Chlorogenic acid was the most abundant phenolic acid (4.97 mg/100 g dry weight [DW]) at the beginning of the experiment, while it decreased at day 7 and increased again at day 21. However, different trends were observed for some flavonoids, such as luteolin and apigenin. At the beginning of stress treatment, high accumulation of free radicals (H 2 O 2) and lipid peroxidation (MDA) led to elevated expression of most of the flavonoid genes. MDA increased from 22.66 to 43.28 μmol g−1 DW at day 28. CHS gene expression was elevated at day 7, while chi gene expression remained unchanged. At the end of the stress period, most of the flavonoid concentrations and expression of the relevant genes also increased. The results can facilitate selection of appropriate drought conditions to obtain the highest levels of flavonoids such as luteolin and apigenin and phenolic compounds such as chlorogenic acid for improved health benefits. Image 1 • The effect of drought on flavonoid genes and metabolites were assessed in Achillea pachycephalla. • The concentration of the phenolics and flavonoids showed different trends in response to drought. • H 2 O 2 and MDA were elevated at the beginning of drought stress. • Most of the genes were upregulated at the beginning and end days of the stress. [ABSTRACT FROM AUTHOR]

Abstract: Amplified fragment length polymorphism (AFLP) markers were used to assess the genetic diversity of 57 Achillea accessions belonging to five species, A. millefolium, A. filipendulina, A. tenuifolia, A. santolina and A. biebersteinii. Nine AFLP primer combinations were used, which produced 301 polymorphic bands. In most species, a high level of genetic variation was detected among the genotypes. The Jaccard''s similarity indices (J), based on AFLP profiles, were subjected to UPGMA cluster analysis. Application of Mantel''s test for cophenetic correlation to the cluster analysis indicated the high fitness of the accessions to a group (r =0.918). The dendrogram generated revealed five major groups corresponding to five species. The principle coordinate analysis (PCoA) data confirmed the results of the clustering. Among the species, A. teunifolia and A. santolina showed the greatest and the least genetic diversity, respectively. A. filipendulina accessions were acquired primarily from the same ecological regions of western Iran. Accessions belonging to A. biebersteinii originated from the Isfahan province and were separated from other species at the root of the dendrogram. The results of the clustering method, based on AFLP markers, corresponded closely with the geographical origins of the genotypes. The results of the present study could contribute to a better understanding and management of conservation and exploitation of the Achillea germplasm. [Copyright &y& Elsevier]

Abstract: In the present research, we used microsatellite markers to study the genetic diversity and phylogenetic analysis among 75 pomegranate genotypes from Iran, Japan, Turkmenistan, Russia, Italy and USA. Ten out of 25 primer pairs showed 12 polymorphic loci and revealed 38 alleles with an average of 3.1667 alleles per locus and the mean of polymorphic information content (PIC) was calculated as 0.358. Comparing the group of genotypes from different countries revealed that the Iranian genotypes have the highest genetic diversity. The analysis of molecular variance (AMOVA) showed that the high level of genetic diversity occurred within groups and low level of that obtained among them. According to the results, most of the Russian accessions clustered with the Iranian genotypes and some of the American genotypes were grouped with Turkmenistan accessions. Also unknown genotypes showed the close relationships to Turkmenistan and Iranian ones. The results could show the existence of the common ancestors among the genotypes and probably confirms the hypothesis that pomegranate spread from central Asia, especially parts of Iran and neighboring areas such as Turkmenistan to other regions of the world. [Copyright &y& Elsevier]

Abstract: Pomegranate (Punica granatum L.) is one of the oldest fruits known to mankind and is one of the most important endemic horticultural plants in Iran. To investigate the genetic diversity of Iranian pomegranates, efficiency of universal chloroplast microsatellite loci on 51 cultivated, wild and ornamental Iranian genotypes and five genotypes from outside of Iran as outgroups was assessed. The results showed that 16 loci out of 25 loci were polymorphic and revealed 39 alleles with an average of 2.44 alleles per locus. The range of polymorphism information content (PIC) was 0.02–0.39 (average, 0.24), which shows that the majority of loci are informative. The Nei''s gene diversity varied from 0.02 to 0.51, with an average of 0.29. Cluster analysis using neighbor-joining method at the genetic similarity value of 0.90 grouped the 56 genotypes into seven main groups. Pomegranate genotypes were classified based on cultivation and geographical regions for analysis of genetic diversity within and among groups and performed the analysis of molecular variance (AMOVA), which results showed significant differences among groups. It can be concluded that chloroplast microsatellite markers are useful tools to study the genetic diversity of pomegranate genotypes. [Copyright &y& Elsevier]

Abstract: Genetic diversity of 47 Mahaleb cherry genotypes (Prunus mahaleb L.) and six sweet cherry accessions (Prunus avium L.) was studied using 13 SRAP primer combinations. The number of polymorphic fragments detected per primer combination ranged from 1 to 10 bands with an average 4.23 bands. Average PIC was 0.42 over all primer combinations. Cluster analysis using UPGMA method and Dice’s coefficient grouped the species into two main clusters with similarity coefficient ranging from 0.16 to 0.93. Sum of first three PCAs could be represented most of (65.64%) the total variation in the original dimensions and confirmed the results of cluster analysis. Based on AMOVA results, the allele numbers among groups and species studied in this research were more than those observed within them. This is the first report of using SRAP marker as a tool for determining genetic variation among and within P. mahaleb and P. avium. [Copyright &y& Elsevier]