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Darush Struss, Riaz Ahmad, Stephen M. Southwick, and Manuela Boritzki

Simple sequence repeats (SSRs) and amplified fragment-length polymorphisms (AFLPs) were used to evaluate sweet cherry (Prunus avium L.) cultivars using quality DNA extracted from fruit flesh and leaves. SSR markers were developed from a phage library using genomic DNA of the sweet cherry cultivar Valerij Tschkalov. Microsatellite containing clones were sequenced and 15 specific PCR primers were selected for identification of cultivars in sweet cherry and for cross-species amplification in Prunus. In total, 48 alleles were detected by 15 SSR primer pairs, with an average of 3.2 putative alleles per primer combination. The number of putative alleles ranged from one to five in the tested cherry cultivars. Forty polymorphic fragments were scored in the tested cherry cultivars by 15 SSRs. All sweet cherry cultivars were identified by SSRs from their unique fingerprints. We also demonstrated that the technique of using DNA from fruit flesh for analysis can be used to maintain product purity in the market place by comparing DNA fingerprints from 12 samples of `Bing' fruit collected from different grocery stores in the United States to that of a standard `Bing' cultivar. Results indicated that, with one exception, all `Bing'samples were similar to the standard. Amplification of more than 80% of the sweet cherry primer pairs in plum (P. salicina), apricot (P. armeniaca) and peach (P. persica L.) showed a congeneric relationship within Prunus species. A total of 63 (21%) polymorphic fragments were recorded in 15 sweet cherry cultivars using four EcoRI-MseI AFLP primer combinations. AFLP markers generated unique fingerprints for all sweet cherry cultivars. SSRs and AFLP polymorphic fragments were used to calculate a similarity matrix and to perform UPGMA cluster analysis. Most of the cultivars were grouped according to their pedigree. The SSR and AFLP molecular markers can be used for the grouping and identification of sweet cherry cultivars as a complement to pomological studies. The new SSRs developed here could be used in cherry as well as in other Prunus species for linkage mapping, evolutionary and taxonomic study.

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Soon O. Park, Dermot P. Coyne, Geunhwa Jung, Paul W. Skroch, E. Arnaud-Santana, James R. Steadman, H.M. Ariyarathne, and James Nienhuis

Our objective was to identify quantitative trait loci (QTL) for seed weight, length, and height segregating in a recombinant inbred line population derived from the common bean (Phaseolus vulgaris L.) cross `PC-50' × XAN-159. The parents and progeny were grown in two separate greenhouse experiments in Nebraska, and in field plots in the Dominican Republic and Wisconsin. Data analysis was done for individual environments separately and on the mean over all environments. A simple linear regression analysis of all data indicated that most QTL appeared to be detected in the mean environment. Based on these results, composite interval mapping (CIM) analysis was applied to the means over environments. For seed weight, strong evidence was indicated for five QTL on common bean linkage groups (LGs) 3, 4, 6, 7, and 8. Multiple regression analysis (MRA) indicated that these QTL explained 44% of the phenotypic variation for the trait. Weaker evidence was found for three additional candidate QTL on bean LGs 4, 5, and 8. All eight markers associated with these QTL were significant in a MRA where the full model explained 63% of the variation among seed weight means. For seed length, CIM results indicated strong evidence for three QTL on LG 8 and one on LG 2. Three additional putative QTL were detected on LGs 3, 4, and 11. The markers associated with the three seed length QTL on LG 8, and the QTL on LGs 2 and 11 were significant in a MRA with the full model explaining 48% of the variation among seed length means. For seed height, three QTL on LGs 4, 6, and 11 explained 36% of the phenotypic variation for trait means. Four of the seven QTL for seed length and two of three QTL for seed height also appeared to correspond to QTL for seed weight. Four QTL for common bacterial blight resistance [Xanthomonas campestris pv. phaseoli (Smith Dye)] and for smaller seed size were associated on LGs 6, 7, and 8. The implications of these findings for breeders is discussed.

Open access

Prashant Bhandari and Tong Geon Lee

shown). Therefore, this array is not readily suited for QTL linkage mapping and/or association studies, particularly genotyping populations derived from crosses between two large-fruited fresh-market tomatoes (S.F. Hutton, personal communication). The

Free access

Jim C. Cervantes-Flores, G. Craig Yencho, Kenneth V. Pecota, Bryon Sosinski, and Robert O.M. Mwanga

). Second, this large mapping population was used to develop the most complete molecular linkage map in sweetpotato to date ( Cervantes-Flores et al., 2008 ); thus, this saturated map could be used for QTL detection. If the individual data points were

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Pei Xu, Tingting Hu, Yuejian Yang, Xiaohua Wu, Baogen Wang, Yonghua Liu, Dehui Qin, Jeffrey Ehlers, Timothy Close, Zhongfu Lu, and Guojing Li

control of both traits. Table 1. Segregation of flower and seedcoat color in an F 1 and recombinant inbred line population. Because only 96 lines of the RIL population were genotyped for linkage mapping ( Xu et al., 2011 ) within which Nos. 27 and 160

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De-Kun Dong, Jia-Shu Cao, Kai Shi, and Le-Cheng Liu

; Lincoln et al., 1992 ) was used to perform the linkage analysis. One hundred forty-one AFLP markers were grouped into 17 linkage groups at logarithm of odds (LOD) 3.0 and then ordered at LOD 2.0. Kosambi mapping function ( Kosambi, 1944 ) was used to

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Nina R.F. Castillo, Barbara M. Reed, Julie Graham, Felicidad Fernández-Fernández, and Nahla Victor Bassil

per primer pair. z Linkage mapping. For mapping in the ‘Glen Moy’ × ‘Latham’ (GM × L) population, primers were initially tested on the parents and 10 selected progeny. For polymorphic loci, one primer was fluorescently end-labeled with

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Ivan Simko and Jinguo Hu

The most common method for mapping genes in lettuce and other cultivated plant species is genetic linkage mapping. This approach involves generating populations derived from single crosses and estimating recombination frequencies between marker

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Thierry Pascal, Fred Pfeiffer, and Jocelyne Kervella

. The second was to assess linkage relationships between resistance to powdery mildew and two major genes brought by the peach rootstock cultivar Rubira® (clone S2605), used here as the powdery mildew-susceptible parent and homozygous, respectively, for

Free access

Dario J. Chavez and José X. Chaparro

odds score 10. Map of the seedless locus Fs . Genetic distance (cM) between markers is presented on the left side of the linkage map using Kosambi's mapping function. Primer names are shown on the right by the operon primer code, linkage phase (r