A linkage map for flowering dogwood (Cornus florida L.) based on microsatellite markers

Abstract

A genetic linkage map of Xowering dogwood (Cornus Xorida L.) was constructed using 94 individuals derived from a cross of two F 1 trees designated 97-6 and 97-7, which were originally from a cross between 'Appalachian Spring' and 'Cherokee Brave'. Out of approximately 800 SSR loci examined, 271 were polymorphic between 'Appalachian Spring' and 'Cherokee Brave', but were monomorphic between 97-6 and 97-7. These 271 segregating markers were used to build a linkage map for Xowering dogwood. Eleven linkage groups were obtained with a log-of-odds (LOD) value of 6.0 using JoinMap® 4.0 software, which matches the chromosome number of Xowering dogwood haploid genome. This linkage map consisted of 255 SSR loci, spanned a total of 1,175 centimorgans (cM) with an average internal distance of 4.6 cM. Several larger gaps and slight clustering of markers were present on this linkage map. This is the Wrst linkage map of Xowering dogwood and will be a fundamental tool for new gene identiWcation and marker-assisted selection in our Xowering dogwood breeding program.

Genetic analysis and associated SRAP markers for flowering traits of chrysanthemum (Chrysanthemum morifolium)

“…This makes it practically difficult to obtain advanced generations of inbred lines of the sort used for genetic research in self-compatible species. A number of tree species are similarly heterozygous, and in these the F 1 generation is generally used as a pseudo-F 2 population for genetic studies (Grattapaglia and Sederoff 1994;Marron and Ceulemans 2006;Song et al 2005;Wang et al 2009). Such a pseudo-F 2 population was also widely applied in horticultural crops of m population mean, d major gene additive effect, h major gene dominant effect, d a the additive effect of the first pair of major genes, d b the additive effect of the second pair of major genes, h a the dominance effect of the first pair of major genes, h b the dominance effect of the second pair of major genes, i additivity 9 additivity interaction effect, j ab additivity 9 dominance interaction effect, j ba dominance 9 additivity interaction effect, l dominance 9 dominance interaction effect, r p 2 phenotypic variance, r mg 2 major gene variance, h mg 2 major gene heritability self-incompatibility such as artichoke (Lanteri et al 2006;Portis et al 2009) and garlic .…”

Polymorphism of Microsatellite Markers in Papaya (Carica papaya L.)

“…Polymorphisms based on SSR are more powerful to estimate genetic parameters of populations and understand detailed patterns of gene flow and parentage composition (Dow and Ashley 1996;Collevatti et al 1999;Ren et al 2008). Besides, SSRs markers are more useful for genetic mapping (Oliveira et al 2008b;Wang et al 2009), and ancestry studies (Guilford et al 1997;Gianfranceschi et al 1998).…”

Development of DNA markers that discriminate between white- and blue-flowers in Japanese gentian plants

“…Namely, the v 2 P values were \ 0.05 and observed segregation ratio did not fit Mendelian expectations. The exact reason for the unexpected segregation ratio is unknown, but many biological factors, such as unequal crossover during meiosis, chromosome loss, non-random union of gametes, zygotic embryo abortion, changes in genetic load, or lethal alleles may distort allele segregation, as reported previously (Taylor and Ingvarsson 2003;Wang et al 2009). Japanese gentian shows self-pollinated weakness; therefore it is likely that many recessive lethal genes contributed to the unexpected segregation ratio under these heterozygous conditions.…”