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Developing successful strategies to ensure future increase in yield of soybean and peanut crops hinges in part, on improving the genetic basis of the cultivars. Knowledge of genetic relationships in crop breeding programs provides valuable information that can be used by plant breeders as a parental line selection tool. So far, a thorough analysis of genetic diversity among the soybean and peanut genotypes grown in Turkey had not been attempted at DNA level. In this study, inter-simple sequence repeats (ISSR) and sequence-related amplified polymorphism (SRAP) markers were used to evaluate the genetic diversity between 21 soybean and 32 peanut cultivars and breeding lines adapted to different regions of Turkey. The ISSR analysis, which was performed with 46 primers in soybean and 47 primers in peanut, yielded 31 and 26 polymorphic bands, respectively, while 26 and 17 polymorphic amplicons were amplified by 34 and 36 SRAP primer combinations in soybean and peanut, respectively. The unweighted pair group method with arithmetic means dendrograms (UPGMA), based on Jaccard similarities,were obtained from the combined ISSR + SRAP data for both soybean and peanut. In soybean, UPGMA dendrogram clustered all soybean cultivars into the same group except 'Yeşilsoy', whereas, in peanut, it separated cultivars southwest runner and spantex from all the other cultivars, breeding lines, and plant introductions. In light of the narrow germplasm base of soybean and peanut genotypes grown in Turkey, a renewed emphasis should be placed on the introduction of new sources of germplasm into the breeding pool in order to enhance genetic variability to permit continued progress in developing high yielding cultivars and lead to greater gains for selections. The results obtained from this study will be helpful for soybean and peanut breeders in Turkey to gain information about genetic diversity and will enable them to make a future strategy for broadening the genetic basis of these crops. [ABSTRACT FROM AUTHOR]

Wild soybean (Glycine soja Sieb. & Zucc.), the progenitor of cultivated soybean (Glycine max (L.) Merr.), is widely distributed in the Sino-Japanese Floristic Region (SJFR). Therefore, it is an excellent model organism to study the effect of Quaternary climatic changes on the distribution and migration of plant taxa in the SJFR. To investigate the phylogeography of G. soja, a total of 632 individuals representing 52 populations throughout the species distribution range were genotyped by using the sequencing data of a nuclear locus, AF105221, and a chloroplast locus, trnQ-rps16. We detected a total of 23 haplotypes from two loci, including five common and 18 rare haplotypes. Among them, 17 rare haplotypes were limited to Northeast Asia (Northeast China (NEC) and Korea) and the Yangzi River basin (middle and downstream of the Yangzi River (MDYR) and the eastern end of Southwest China (SWC)). Moreover, two common haplotypes were detected throughout the species distribution wide range. All the haplotypes from Japan and the Korean peninsula were also found in China. The haplotype distribution patterns of the two loci suggested that Northeast Asia (NEC and Korea) and the Yangzi River basin (MDYR and the eastern end of SWC) might have been the refugia for G. soja during the Quaternary glacial period, and G. soja expanded rapidly after the end of the Last Glacial Maximum. There was a land bridge between East China, the Korean peninsula, and Japan that permitted gene flow among populations of these regions in the ice age during the Quaternary. [ABSTRACT FROM AUTHOR]

Isoflavones prevent the incidence of cancer, reduce cardiovascular problems, and decrease menopausal symptoms. In soybean (Glycine soja Sieb. & Zucc.) seeds, the content is greatly affected by growing conditions. The variations in soy-isoflavone content were investigated by growing 346 Korean wild soybean accessions from natural habitats under the same agroclimatic conditions. Highperformance liquid chromatography was used to measure the profiles of six soy-isoflavones, i.e. glycosides (daidzin, glycitin, genistin) and malonyl glycosides (malonyl-daidzin, malonyl-glycitin, and malonyl-genistin). The soy-isoflavone content of the wild soybeans ranged from 0.5 to 5.51 mg/g with an average of 2.78 mg/g. The highest mean total soy-isoflavone was genistin (1.393 mg/g), followed by daidzin (0.939 mg/g) and glycitin (0.250 mg/g). Korean wild soybean seeds examined in this study were rich in malonyl-genistin. An increasing trend for total soy-isoflavone content was observed from the north to the southeast in the geographical distribution sites, which signifies the effect of genotype and collection site. The information generated in this report will greatly aid soybean breeding stratagems aimed at improving soy-isoflavone concentration in soybean seeds. [ABSTRACT FROM AUTHOR]

The plant cellulose synthase gene superfamily belongs to the category of type-2 glycosyltransferases, and is involved in cellulose and hemicellulose biosynthesis. These enzymes are vital for maintaining cell-wall structural integrity throughout plant life. Here, we identified 78 putative cellulose synthases (CS) in the soybean genome. Phylogenetic analysis against 40 reference Arabidopsis CS genes clustered soybean CSs into seven major groups (CESA, CSL A, B, C, D, E and G), located on 19 chromosomes (except chromosome 18). Soybean CS expansion occurred in 66 duplication events. Additionally, we identified 95 simple sequence repeat makers related to 44 CSs. We next performed digital expression analysis using publically available datasets to understand potential CS functions in soybean. We found that CSs were highly expressed during soybean seed development, a pattern confirmed with an Affymatrix soybean IVT array and validated with RNA-seq profiles. Within CS groups, CESAs had higher relative expression than CSLs. Soybean CS models were designed based on maximum average RPKM values. Gene co-expression networks were developed to explore which CSs could work together in soybean. Finally, RT-PCR analysis confirmed the expression of 15 selected CSs during all four seed developmental stages. [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]