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Retrotransposons have been highly studied in monocots; however retrotransposon diversity in dicot crops has not been well documented. Our objective was to assess the diversity harbored by field pea landraces using retrotranposon markers. In this research, molecular characterization of 104 landraces and 34 field pea breeding lines was assessed using newly developed iPBS-retrotransposon markers. The 12 iPBS-retrotransposon primers generated a total 106 scorable bands, and 81 of these were found to be polymorphic (76.4%), with an average of 6.75 polymorphic fragments per primer. Polymorphism information content (PIC) ranged from 0.33 to 0.84 with an average of 0.61. It was evident that field pea landraces from the same geographical region were often placed in different groups in the neighbor joining analysis, indicating that grouping based on genetic parameters was not closely related to the geographical origin. The population structure was determined by using STRUCTURE software, and three populations at K = 3 and five populations at K = 5 were identified among landraces. The plentiful diversity present in Turkish field pea landraces could be used as genetic resource in designing breeding program, and may also contribute to worldwide pea breeding programs. Our data also suggested a role of iPBS-retrotransposons as ‘a universal marker’ for molecular characterization of pea germplasm. [ABSTRACT FROM AUTHOR]

Even though lentil has been an important food legume for centuries, genetic studies in lentil are still in their infancy. Genetic diversity and relationships among wild Lens species from Turkey has seldom been investigated. Additionally, a limited number of simple sequence repeat (SSR) markers have been developed for use in breeding and genetic studies of lentil crop. In this study, molecular characterization of 50 accessions mostly from Turkey, belonging to 6 wild and 1 cultivated Lens species, was performed using newly developed inter-primer binding site (iPBS) retrotransposons and inter-SSR (ISSR) markers. The 10 iPBS primers generated a total of 151 scorable bands, of which 150 were polymorphic (99.3%) with an average of 15.0 polymorphic fragments per primer. The 10 ISSR primers detected 138 scorable bands showing 100% polymorphism, with an average of 13.5 bands per primer. The average polymorphism information content (PIC) value for ISSR markers (0.97) was higher than that for iPBS markers (0.90). Lens orientalis was found to be the most diverse species, raising the possibility of wide crosses with cultivated species Lens culinaris . Cultivated varieties also showed high level of polymorphism, at 82.92% and 51.92% with ISSR and iPBS markers, respectively. Lens lamottei and Lens tomentosus were found as the least polymorphic species using both marker systems. The grouping of accessions and species within clusters were almost similar when iPBS and ISSR graphs were compared. Our data also suggested the role of iPBS-retrotransposons as ‘ a universal marker ’ for molecular characterization of wild and cultivated Lens species. [ABSTRACT FROM AUTHOR]

Methods for the diagnostics and detection of plant pathogens need to be quick, simple, reliable, and cost effective. In the present study, inter-priming binding sites (iPBS)-retrotransposons were used to study the genetic diversity of 96 isolates belonging to 16 different fungal species at intra- and inter-species levels. The 6 iPBS-retrotransposon primers amplified 389 bands, of which 387 were polymorphic (99%) with an average of 64.83 polymorphic fragments per primer. Polymorphism information contents per primers ranged from 0.976 to 0.870 with the average being 0.972. Neighbor-joining analysis differentiated all fungal isolates according to their species, and at the intra-specific level revealed considerable genetic variability among fungal isolates. The data supports the use of iPBS-retrotransposons as ‘a universal marker’ for the molecular characterization of different fungal species. It also suggests that only one or a few iPBS-retrotransposon primers would be sufficient for the discrimination of fungal isolates at both intra- and inter-species levels. [ABSTRACT FROM AUTHOR]

Glycine soja , also called wild soybean, is the wild ancestor of domesticated soybean ( Glycine max ), and one of the world's major cultivated crops. Wild soybean is a valuable resource for the breeding of cultivated soybean and harbors useful genes or agronomic traits. To use and conserve this valuable resource, we conducted a study to evaluate the genetic diversity and population structure of wild soybean using the sequencing data of two nuclear loci ( AF105221 and PhyB ) and one chloroplast locus ( trnQ - rps16 ) of more than 600 individuals representing 53 populations throughout the natural distribution range. The results showed that most of the variation was found within the populations and groups, but significant genetic differentiation was also detected among different eco-geographical groups. Correlations between genetic and geographical distance at all the loci were consistent with the isolation by distance gene flow model. G. soja exhibited the highest genetic diversity in middle and downstream of Yangzi River (MDYR) region, followed by North East China (NEC), and was the lowest in North West China (NWC). We concluded that both in situ and ex situ conservation strategies required for wild soybean populations, especially which are native to MDYR and NEC regions. [ABSTRACT FROM AUTHOR]

Korea is considered one of the centers of genetic diversity for cultivated as well as wild soybeans. Natural habitats of wild soybeans are distributed across the Korean mainland and the islands surrounding the Korean peninsula. In this study, the genetic diversity of 100 mainland Korean wild soybean accessions was evaluated by using 42 simple sequence repeat markers covering 17 soybean chromosomes. All analyzed loci were polymorphic and a total of 114 alleles were found. The observed average genetic diversity was low (0.4). The results showed that the 100 selected accessions did not exactly follow the geographical distribution. These results were further confirmed by the phylogeny inferred from five morphological characteristics (i.e., leaf shape, leaf area, plant shape, seed area, and 100-seed weight). Together, the genetic and morphological evaluations suggested conclusively that the selected population did not follow the geographical distribution pattern. The present study could provide useful information for the ex situ conservation and exploitation of wild soybean accessions in soybean improvement stratagems, and will aid in further understanding about the phylogeography of the species in the Korean center of diversity. [ABSTRACT FROM AUTHOR]

Genetic diversity and its geographical patterns play a very important role in species conservation and exploitation. Here, nucleotide polymorphism patterns of four single copy nuclear gene loci in wild ( Glycine soja ) and cultivated soybean ( Glycine max ) populations from different geographical regions as well as their demographic history were analyzed. The results showed that: (1) Southern subpopulation has the highest, while central subpopulation revealed the lowest genetic diversity among three Chinese G . soja subpopulations. (2) Northern Chinese G . max subpopulation depicted higher genetic diversity than other two Chinese, Korean, Japanese and American G . max subpopulations. (3) Significant genetic differentiation ( P < 0.001) was observed among Chinese G . soja subpopulations from three ecological zones. There was also a significant genetic differentiation（ P < 0.01）between three Chinese and Japanese subpopulations of G . max . (4) The demographic dynamics revealed that effective population size of G . soja is expanding, while it was constant in G . max . G . soja is a useful germplasm resource to widen the genetic diversity of G . max . This study suggests that native populations of G . soja from different geo-ecological regions should be protected to conserve the genetic diversity. [ABSTRACT FROM AUTHOR]