The genetic relationships among peach [Prunus persica (L.) Batsch], almond [P. dulcis (Mill.) D.A. Webb or P. amygdalus (L.) Batsch] and 10 related Prunus species within the subgenus Amygdalus were investigated using simple sequence repeat (SSR) markers. P. glandulosa Pall. was included as an outgroup. Polymorphic alleles were scored as present or absent for each accession. The number of alleles revealed by the SSR analysis in peach and almond cultivars ranged from one to three whereas related Prunus species showed a range of one to 10 alleles. Results demonstrated an extensive genetic variability within this readily intercrossed germplasm as well as the value of SSR markers developed in one species of Prunus for the characterization of related species. Mean character difference distances were calculated for all pairwise comparisons and were used to construct an unrooted dendogram depicting the phenetic relationships among species. Four main groups were distinguished. Peach cultivars clustered with accessions of P. davidiana (Carr.) Franch. and P. mira Koehne. The second group contained almond cultivars. A third group included accessions of P. argentea (Lam) Rehd., P. bucharica Korschinsky, P. kuramica Korschinsky, P. pedunculata Pall, P. petunikowii Lits., P. tangutica (Spach) Batal., and P. webbii (Spach) Vieh.. P. glandulosa and P. scoparia Batal. were included in a fourth group.
P. Martínez-Gómez, S. Arulsekar, D. Potter, and T.M. Gradziel
Amnon Levi, Claude E. Thomas, M. Newman, O.U. K. Reddy, X. Zhang, and Y. Xu
Wide phenotypic diversity exists among American heirloom cultivars of watermelon (Citrullus lanatus var. lanatus). However, in published studies, low or no polymorphism was revealed among those heirlooms using isozyme or randomly amplified polymorphic DNA (RAPD) markers. In this study, experiments with inter-simple sequence repeat (ISSR) [also known as simple sequence repeat-(SSR-) anchored primers] and amplified fragment-length polymorphism (AFLP) markers produced high polymorphisms among watermelon heirloom cultivars. ISSR (111) and AFLP (118) markers (229 total) identified 80.2% to 97.8% genetic similarity among heirloom cultivars. The phylogenetic relations based on ISSR and AFLP markers are highly consistent with the parental records available for some of the heirloom cultivars, providing confidence in the dendogram constructed for heirlooms based on similarity values. As compared with RAPD markers, ISSRs and AFLPs are highly effective in differentiating among watermelon cultivars or elite lines with limited genetic diversity.
Chunxian Chen and William R. Okie
Peach (Prunus persica) cultivars maintained at the U.S. Department of Agriculture program at Byron, GA, have never been characterized with any molecular markers. In this study, 20 microsatellite markers were used to genotype 112 cultivars and the data were analyzed to discern their population structure and phylogenetic relationships. STRUCTURE simulations revealed four K clusters and broad genetic admixture among the cultivars. Principal coordinate analysis (PCoA) showed the cultivar groups from western, northeastern, and southeastern U.S. states were adjacent to each other except cultivars from Michigan (close to most southeastern state groups) and Florida (most distant from the other groups). Principal component analysis (PCA) showed that these cultivars had no obvious PCA partitioning boundaries. The intertwined distribution in both PCoA and PCA partitions suggested many of them were genetically closely related to each other largely because most shared same ancestral parentages. Most pairwise distance means within and between the cultivar groups were relatively low, suggesting close phylogenetic relations among those cultivars, as were demonstrated in the phylogenetic tree. Limiting factors and perspectives relevant to peach breeding are discussed.
Masanori Honjo, Susumu Yui, and Miyuki Kunihisa
strawberry. History, breeding and physiology. Holt, Rinehart and Winston, New York, NY Federova, N. 1946 Crossability and phylogenetic relations in the main European species of Fragaria Comp. Rend. Acad. Sci. USSR 53 545 547 Haymes, K.M. Henken, B. Davis, T
Kim E. Hummer, James R. Ballington, Chad E. Finn, and Thomas M. Davis
://faostat.fao.org/site/567/DesktopDefault.aspx?PageID=567#ancor > Fedorova, N.J. 1946 Crossability and phylogenetic relations in the main European species of Fragaria C. R. (Dokl.) Acad. Sci. USSR 52 545 547 Ferguson, A.R. Ferguson, L.R. 2003 Are kiwifruit really good for
Thomas E. Marler and Nirmala Dongol
traits such as their basal position in seed plant phylogenetic relations (Norstog and Nicholls, 1997). However, research on organ development of cycads has been ignored in relation to other horticultural species that historically have commanded greater
Emmanouil N. Tzitzikas, Antonio J. Monforte, Abdelhak Fatihi, Zacharias Kypriotakis, Tefkros A. Iacovides, Ioannis M. Ioannides, and Panagiotis Kalaitzis
an average major allele frequency of 0.45 compared with 0.78, which was the average major allele frequency of Greek/Cypriot cultigens. Phylogenetic relations among melon accessions. The unrooted NJ tree based on the genetic distance by Nei et
Neil O. Anderson, Adnan Younis, and Ye Sun
), Lilium ( Dai et al., 2007 ; Lee et al., 1993 ; Persson et al., 1998 ), and Scaevola ( Swoboda and Bhalla, 1997 ). RAPD markers were used to infer phylogenetic relations and resolve paternity issues in wide hybrid lily crosses ( Wen and Hsiao, 2001