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Linum species are of various benefits to mankind, such as fiber and oil source, ornamental as well as medicinal values. Population genetic study by using molecular markers can produce valuable information on genetic structure, genetic variability, genetic fragmentation and gene flow among plant populations. These data can be used in conservation and breeding programs of economically important plants. We performed population genetic study on 6 populations of two Linum species, namely L. usitatissimum L. and wild species L. austriacum L., by using SRAP molecular markers. In general low genetic variability was observed in both studied species, but a little higher genetic diversity occurred in the wild species L. austriacum (6.25-21.88%). AMOVA revealed significant genetic difference among these populations that was supported by Gst and Dest parameters of genetic differentiation. K-Means clustering and STRUCTURE analyses identified three distinct genetic groups within each species. Nm and population assignment test did not show the occurrence of gene flow among the studied populations and suggested genetic fragmentation in both Linum species. Predominant selfing in L. usitatissimum may be the reason for genetic uniformity within each population and genetic differentiation among these populations. L. austriacum shows distyly, which promotes pollination between different floral morphs, and prevents self-pollination. This may be the reason for higher degree of within population genetic variability in this species. [ABSTRACT FROM AUTHOR]

Hybridization is one of the main strategies in cotton breeding producing new genotypes and increasing the genetic diversity in the cotton germplasm available. Thirty RAPD and ten ISSR markers were use to assess the genetic diversity in F2 progenies of tetraploid cotton hybrid genotypes (Gossypium hirsutum). Fifteen of 30 RAPD primers produced 126 reproducible bands with 66.44% polymorphism. Among the primers used, OPA09 primer showed highest value of number of effective allele (Ne), Shannon index (I), Nei's genetic diversity (H) (1.814, 0.638 and 0.447 respectively). The value of genetic identity varies from 0.65 between Siokra x No.200 and Tabladila x Siokra to 0.93 between Tabladila x Sindose and Sindose x No.200. Eight of 10 ISSR primers provided 87 reproducible bands with 67.82 % of polymorphism. UBC834 primer with AG repeats as a core sequence showed the highest value of Ne (1.570), I (0.477) and H (0.323) while combined primer UBC807+(GA)9T showed the highest PIC value (0.500). Based on ISSR data obtained, the hybrid cultivars Mehr x Tabladila and Tabladila x Siokra showed the lowest Nei's genetic identity (0.59), while, the hybrid cultivars No.200 x Belilzovar and Tabladila x Sindose showed the highest value. UPGMA Dendrograms obtained in RAPD and ISSR as well as combined RAPD and ISSR markers grouped together the hybrid genotypes which have Mehr cultivar as one of their parents. In conclusion, this study showed that using combined RAPD and ISSR data provides higher resolution of molecular profiles in hybrid genotypes [ABSTRACT FROM AUTHOR]

Pomegranate Punica granatum (Lythraceae) is one of the most important horticultural plants of Iran cultivated in different areas with different cultivars having specific fruit characteristic such as size, color, time of ripening, disease resistance, taste, etc. The present study considers morphological and RAPD analysis of eighteen pomegranate cultivars of the country. Agro-morphological characters were studied by using factor analyses. Clustering separated cultivars in distinct groups indicating their morphological differences. Forty RAPD primers used produced 182 bands, out of which 414 bands were polymorphic (about 44%) with average of 4.55 polymorphic bands for each primer. Eight unique bands (cultivar-specific) were observed. Two cultivars of Malas Yazdi and Poost Ghermez Mamooli showed the highest similarity among the cultivars studied [ABSTRACT FROM AUTHOR]

Numerous olive cultivars are cultivated in Iran, mainly in the north. Ninety-two accessions belonging to 10 main olive cultivars were screened by 13 microsatellite markers revealing high genetic variability both within and between cultivars. In total, 72 alleles were detected with a mean number of 5.5 alleles per locus. Twenty-four unique allelic patterns were observed, whereas six genotypes showed 15 unique alleles. Heterozygosity ranged from 0.00 to 0.98, whereas the mean number of discrimination power and polymorphic information content were 0.55 and 0.54, respectively. The combination of 5 simple sequence repeat markers made discrimination of 84% of all accessions included in the study possible. The existence of homonyms, synonyms, or mislabeling as well as intracultivar polymorphism was revealed by allele differences between accessions of the same denomination. The phenogram showed variability among as well as between some cultivars, but most accessions with the same generic names were grouped together. [ABSTRACT FROM AUTHOR]

RAPD markers variations were studied in ten pomegranate cultivars. Twenty RAPD primers used produced 323 bands. Nineteen bands were common in all the cultivars while other bands were polymorph. Some specific bands were identified in the cultivars studied which may be used in cultivars discrimination. Primers OPB-07 produced the highest number of polymorphic bands (5.9%[U1] ), while primers OPI-16 produced the least number of polymorphic bands (5.2%[U2] ). Different similarity coefficients determined among the cultivars studied, showed the highest value of genetic similarity was observed between Abdandan and Suski cultivars while Shasavar and Shahidaneh cultivars differed from the other cultivars and stand far from them in NJ and Bayesian trees. Some specific bands/loci were observed in pomegranate cultivars studied which may be used for cultivar identification. [ABSTRACT FROM AUTHOR]

L. amplexicaule L. grows in different regions of Iran and forms several populations that can be invasive in some area. Morphological and genetic variation of L. amplexicaule in Iran was studied to evaluate the differentiation among three presumed varieties within this species. Morphometric study was accompanied by the analysis of ISSR and chloroplast genome (psbA-trnH). Results of the molecular methods show that L. amplexicaule var. bornmuelleri Mennema. does not form any genetically distinct group. Genetic study of 103 plant specimens of 13 different populations using ISSR molecular marker revealed a high degree of within-population (67%) and among (33%) populations genetic diversity. AMOVA and Gst analyses produced a significant difference. Nm estimation revealed certain degree of gene flow/shared alleles between these populations, indicating that L. amplexicaule is predominantly an out-crossing species in Iran. Mantel test produced significant correlation between genetic distance and geographical distance of the studied populations (r = 0.097, P = 0.04). STRUCTURE plot identified two main gene pools for this species in Iran. [ABSTRACT FROM AUTHOR]

The genus Tragopogon L. with about 110-150 species is distributed in Asia and Europe, while it is represented by 26 species in Iran. Hybridization and polyploidy occurs in the genus Tragopogon that bring about extensive morphological variation in its species. Tragopogon buphthalmoides (Asteraceae) is a perennial herb with common Persian name "Sheng e Iran" and "Sheng e cheshmgaavi" and is used as traditional medicine. Two varieties have been cited for this species in the country, but due to extensive morphological variability, it is difficult to delimit the two varieties. Therefore, the present study was performed to delimit these varieties by using both morphological and molecular markers (cpDNA and ISSRs). We also aimed to provide data on population genetics of the studied species due to its medicinal importance. In total 134 plant specimens of T. buphthalmoides were randomly collected from 16 geographical populations in 7 provinces. The studied plants were considered as two different varieties based on morphological criteria and were subjected to numerical and phylogenetic analyses. PCOA plot of morphological data, identified some plants with intermediate characters. Moreover, MDS plot of ISSR data and ML tree of cpDNA sequences, did not separate plants of the two varieties and the plants were placed intermixed. Therefore, we consider T. buphthalmoides as a single species with extensive morphological variability and it is complex species. Population genetic study identified four genetic groups in the country, while, STRUCTURE analysis based on admixture model as well as population assignment test revealed some degree of gene flow in the studied populations. [ABSTRACT FROM AUTHOR]

Ziziphora tenuior L. is a medicinal plant species of the genus Ziziphora (Labiatae) that grows in different areas of Iran. In order to study the population genetic structure in Ziziphora tenuior,we collected 107 plant specimens from 20 geographical populations that are located in 17 provinces. ISSR molecular markers were used for genetic diversity analysis. The populations studied revealed intra- and inter-population genetic variability. AMOVA test showed significant genetic difference among the studied populations. STRUCTURE plot identified two main gene pools for Ziziphora tenuior in Iran. These populations showed isolation by distance and restrict gene flow occurred among them. [ABSTRACT FROM AUTHOR]