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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]

A doubled haploid (DH) population derived from a cross between the Japanese cultivar 'Fukuho-kumogi' and the Israeli wheat line 'Oligoculm' was used to map genome regions involved in the expression of grain yield, yield components, and spike features in wheat ( Triticum aestivum L). A total of 371 markers (RAPD, SSR, RFLP, AFLP, and two morphological traits) were used to construct the linkage map that covered 4190 cM of wheat genome including 28 linkage groups. The results of composite interval mapping for all studied traits showed that some of the quantitative trait loci (QTL) were stable over experiments conducted in 2004 and 2005. The major QTL located in the Hair-Xpsp2999 interval on chromosome 1A controlled the expression of grains/spike ( R2 = 12.9% in 2004 and 22.4% in 2005), grain weight/spike ( R2 = 21.4% in 2004 and 15.8% in 2005), and spike number ( R2 = 15.6% in 2004 and 5.4% in 2005). The QTL for grain yield located on chromosomes 6A, 6B, and 6D totally accounted for 27.2% and 31.7% of total variation in this trait in 2004 and 2005, respectively. Alleles inherited from 'Oligoculm' increased the length of spikes and had decreasing effects on spike number. According to the data obtained in 2005, locus Xgwm261 was associated with a highly significant spike length QTL ( R2 = 42.33%) and also the major QTL for spikelet compactness ( R2 = 26.1%). [ABSTRACT FROM AUTHOR]

The lateral spikelets of two-rowed barley are reduced in size and sterile, but in six-rowed barley all three spikelets are fully fertile. The trait is largely controlled by alleles at the vrsl locus on chromosome arm 2HL, as modified by the allele present at the / locus on chromosome arm 4HS. Molecular markers were developed to saturate the 4HS region by exploiting expressed sequence-tags, either previously mapped in barley to this region, or present in the syntenic region of rice chromosome 3. Collinearity between rice and barley was strong in the 4.8cM interval BJ468164-AV933435 and the 10cM interval AV942364-BJ455560. A major QTL for lateral spikelet fertility (the I locus) explained 44% of phenotypic variance, and was located in the interval CB873567-BJ4739I6. The genotyping of near-isogenic lines for I placed the locus in a region be-tween CB873567 and EBmac635, and therefore the most likely position of the I locus was proximal to CB873567 in a 5.3 cM interval between CB873567-BJ473916. [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]

Spike morphology is a key characteristic in the study of barley domestication, yield, and use. Multiple alleles at the vrs1 locus control the development and fertility of the lateral spikelets of barley. We developed five amplified fragment length polymorphism (AFLP) markers tightly linked to the vrs1 locus using well-characterized near-isogenic lines as plant materials. The AFLP markers were integrated into three different maps, in which 'Azumamugi' was used as the maternal parent. Of the three maps, Hordeum vulgare L. 'Azumamugi' × H. vulgare 'Golden Promise' showed recombination of the AFLP markers and the vrs1 locus (closest, 0.05 cM), providing the best mapping population for positional cloning of alleles at the vrs1 locus. Conversion of AFLP bands into polymorphic sequence-tagged sites (STSs) is necessary for further high-throughput genotype scoring and for bacterial artificial chromosome (BAC) library screening. We cloned and sequenced the five AFLP bands and synthesized primer pairs. PCR amplification generated DNAs of the same size from all four parental lines for each marker. Restriction endonuclease treatment of e40m36-1110/AccIII, e34m13-260/Psp1406I, e52m32-270/FokI, and e31m26-520/MnlI revealed fragment length polymorphisms between 'Azumamugi' and all the two-rowed parents. Allelism between the AFLPs and corresponding STS markers was confirmed genetically, indicating the usefulness of the STSs as genetic markers. [ABSTRACT FROM AUTHOR]

Vessel dilator is a 3.9-KDa potent anticancer peptide and a valuable candidate in the treatment of conditions such as congestive heart failure and acute renal failure amongst others. Here we report the recombinant production of vessel dilator in Escherichia coli . Three different synthetic ORF's dubbed VDI, VDII and VDIII, each encoding a trimmer of the vessel dilator peptide attached to a His tag sequence at their C- terminal, were synthesized and placed in pET21c expression vectors. The highest yield, following expression in E. coli BL21 (DE3), was recorded with VDII that carried the shortest fusion partner. Subsequent to the initial capture of the fusion protein by a Ni affinity column, the vessel dilator monomers were cleaved by trypsin treatment, and further purified to at least 90% homogeneity by anion exchange chromatography. De-novo sequencing and in vivo anticancer activity tests were used to verify the peptide sequence and its biological activity, respectively. The final yield was estimated to be approximately 15 mg of the purified vessel dilator per gram wet weight of the bacterial cells. [ABSTRACT FROM AUTHOR]

The large intergenic spacer (IGS) region of rDNA is a valuable DNA sequence because it contains the signals for transcription and processing of rRNAs. In this study, we sequenced and analyzed the complete nucleotide of rDNA IGS region of pomegranate for the first time. This IGS sequence was 3,712 bp in length with GC content of 67.8 %. The sequence analysis indicated that the spacer could be divided into three main regions: a central repetitive region and two flanking unique domains on on both sides of the central area. Central region is composed of two repeat families (A and B), and the third region contained two short direct repeats (C1 and C2). By comparisons with the IGS sequence of other plant species and computer-aided searches, we determined the putative transcription initiation and termination sites, and the large number of methylable sites. The presence of some conserved motifs in this region may play an important role in regulation of rRNA transcription. Taken together, the pomegranate IGS revealed the complex structure. However, its organization and structure are similar to most other rDNA spacers studied. [ABSTRACT FROM AUTHOR]

Many studies have investigated the role of miRNAs on the yield of various plants, but so far, no report is available on the identification and role of miRNAs in fruit and seed development of almonds. In this study, preliminary analysis by high-throughput sequencing of short RNAs of kernels from the crosses between almond cultivars 'Sefid' × 'Mamaee' (with small and large kernels, respectively) and 'Sefid' × 'P. orientalis' (with small kernels) showed that the expressions of several miRNAs such as Pdu-miR395a-3p, Pdu-miR8123-5p, Pdu-miR482f, Pdu-miR6285, and Pdu-miR396a were significantly different. These miRNAs targeted genes encoding different proteins such as NYFB-3, SPX1, PGSIP3 (GUX2), GH3.9, and BEN1. The result of RT-qPCR revealed that the expression of these genes showed significant differences between the crosses and developmental stages of the seeds, suggesting that these genes might be involved in controlling kernel size because the presence of these miRNAs had a negative effect on their target genes. Pollen source can influence kernel size by affecting hormonal signaling and metabolic pathways through related miRNAs, a phenomenon known as xenia. [ABSTRACT FROM AUTHOR]

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]

Bermudagrass (Cynodon spp.) is a major turfgrass for home lawns, public parks, golf courses and sport fields and is known to have originated in the Middle East. Morphological and physiological characteristics are not sufficient to differentiate some bermudagrass genotypes because the differences between them are often subtle and subjected to environmental influences. In this study, twenty seven bermudagrass accessions and introductions, mostly from different parts of Iran, were assayed by inter-simple sequence repeat (ISSR) markers to differentiate and explore their genetic relationships. Fourteen ISSR primers amplified 389 fragments of which 313 (80.5%) were polymorphic. The average polymorphism information content (PIC) was 0.328, which shows that the majority of primers are informative. Cluster analysis using the un-weighted paired group method with arithmetic average (UPGMA) method and Jaccard's similarity coefficient (r = 0.828) grouped the accessions into six main clusters according to some degree to geographical origin, their chromosome number and some morphological characteristics. It can be concluded that there exists a wide genetic base of bermudograss in Iran and that ISSR markers are effective in determining genetic diversity and relationships among them. [ABSTRACT FROM AUTHOR]

Abstract: The infection of the model legume Medicago truncatula with Ralstonia solanacearum GMI1000 gives rise to bacterial wilt disease via colonisation of roots. The root and leaf responses to early infection (1 and 3 days post infection) were characterised to investigate the molecular mechanisms of plant resistance or susceptibility. A proteomics approach based on pools of susceptible and resistant recombinant inbred lines was used to specifically target the mechanisms for tolerance. Differential abundances were evidenced for proteins involved in defence (e.g., PR5, PR10, or Kunitz protease inhibitors) and signalling pathways (such as cyclophilin). R. solanacearum inoculation modifies expression levels of those genes, either in both genotypes (AOS1, LOX4, and proteinase inhibitors) or specifically in the resistant line (PR proteins). Exogenous application of salicylic acid (SA) enhanced tolerance to the bacteria, whereas methyl jasmonate (MeJA) enhanced short‐term tolerance then promoted disease in the susceptible ecotype, suggesting that they may mediate defence responses. Conversely, proteomics‐identified genes were also shown to be SA or MeJA responsive. This is the first description of differential response to R. solanacearum in M. truncatula. Our results suggest that root basal defence is activated at 1 dpi, together with the JA pathway. Specific resistance is then evidenced at three dpi, with the up‐regulation of SA‐dependent PR proteins. [ABSTRACT FROM AUTHOR]

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]

The relationships among 55 wheat accessions (47 accessions collected from Iran and eight accessions provided by the Institute of Plant Biology of the University of Zurich, Switzerland) belonging to eight species carrying A genome (Triticum monococcum L., T. boeoticum Boiss., T. urartu Tumanian ex Gandilyan, T. durum Desf., T. turgidum L., T. dicoccum Schrank ex Schübler, T. dicoccoides (Körn. ex Asch. & Graebner) Schweinf. and T. aestivum L.) were evaluated using 31 A genome specific microsatellite markers. A high level of polymorphism was observed among the accessions studied (PIC = 0.77). The highest gene diversity was revealed among T. durum genotypes, while the lowest genetic variation was found in T. dicoccoides accessions. The analysis of molecular variance (AMOVA) showed a significant genetic variance (75.56%) among these accessions, representing a high intra-specific genetic diversity within Triticum taxa in Iran. However, such a variance was not observed among their ploidy levels. Based on the genetic similarity analysis, the accessions collected from Iran were divided into two main groups: diploids and polyploids. The genetic similarity among the diploid and polyploid species was 0.85 and 0.89 respectively. There were no significant differences in A genome diversity from different geographic regions. Based on the genetic diversity analyses, we consider there is value in a greater sampling of each species in Iran to discover useful genes for breeding purposes. [ABSTRACT FROM AUTHOR]