Microsatellite DNA as shared genetic markers among conifer species

Abstract

Polymerase chain reaction (PCR) primer pairs for 21 simple sequence repeat (SSR) loci in Pinus strobus L. and 6 in Pinus radiata D. Don. were evaluated to determine whether SSR marker amplification could be achieved in 10 other conifer species. Eighty percent of SSR primer pairs for (AC)n loci that were polymorphic in P. strobus also amplified SSR loci in two other soft pines of the subgenus Strobus but not in seven hard pines of the subgenus Pinus, nor in Picea glauca (Moench) Voss or Pseudotsuga menziesii (Mirb.) Franco. The six P. strobus SSR primer pairs that did amplify loci from conifers other than soft pines were those that were specific to loci monomorphic within P. strobus. These six loci were also monomorphic within seven other species tested, but four of the loci were polymorphic among species. A comparison of allelic variation among the three soft pine species found only 25 shared alleles among a total of 122 alleles at eight loci. Primer pairs for dinucleotide SSR loci that were polymorphic in Pinus radiata also specifically amplified loci from various other hard pines but not from the soft pines or from the other conifers tested.

Cross-amplification and sequence variation of microsatellite loci in Eurasian hard pines

“…In pines, Echt et al (1999) successfully transferred 80% of the microsatellites tested within subgenus Strobus but only 29% among subgenus Strobus and Pinus, which diverged over 130 million years ago (approximately 13 million generations in pines) according to the fossil record (Miller 1977). Kutil and Williams (2001), using triplet-repeat microsatellites, found high transfer rates (100%) from P. taeda (subsection Australes) to a close relative of the same subsection, P. palustris but only moderate (and similar to our study) transfer success (47%) to P. halepensis (subsection Pinaster).…”

“…Although a number of methods have been developed to circumvent problems associated with repetitive DNA , the transfer of microsatellites between related conifer species is one of the more promising (Echt et al 1999;Kutil and Williams 2001;Shepherd et al 2002). Shepherd et al (2002) reported successful microsatellite transfer in hard pines (subgenus Pinus) for species that diverged a few million generations ago.…”

Somatic stability of microsatellite loci in Eastern white pine, Pinus strobus L.

“…DNA sequences of the PCR primers for the loci examined in this study have been published elsewhere (Cato and Richardson, 1996;Echt et al, 1996;Vendramin et al, 1996). The PCR reaction and amplification conditions were as described by Echt et al (1996Echt et al ( , 1999. Fluorescently labeled amplified PCR products were separated by electrophoresis on a 41 cm polyacrylamide gel (Li-Cor model 4000L automatic DNA sequencer) (Li-Cor, Lincoln, NE, USA).…”

Conservation and synteny of SSR loci and QTLs for vegetative propagation in four Eucalyptus species

“…Other studies have considered cross-species amplification, with varying degrees of primer-sequence conservation being demonstrated in Pinus (Fisher et al 1998), Quercus (Steinkellner et al 1997), Populus (van der Schoot et al 2000 and among conifer species (Echt et al 1999).…”