Origin and genetic diversity of Spartina anglica (Poaceae) using nuclear DNA markers

• Published in: American journal of botany Vol. 88; no. 10; pp. 1863 - 1867
• Main Authors: Ayres, Debra R., Strong, Donald R.
• Format: Journal Article
• Language: English
• Published: United States Botanical Soc America 01.10.2001; Botanical Society of America; Botanical Society of America, Inc
• Subjects: allopolypoid; Biodiversity; Chromosomes; Deoxyribonucleic acid; DNA; Evolution; Flowers & plants; Genetic diversity; Genetic variation; Genetics; Genomes; Genotypes; Hybridity; hybridization; ISSRs; parentage; Plants; Poaceae; Population genetics; RAPDs; Spartina alterniflora; Spartina anglica; Spartina maritima; Spartina ×townsendii; Systematics; ANE, British Isles
• ISSN: 0002-9122; 1537-2197
• DOI: 10.2307/3558362

Spartina alterniflora, introduced into the UK in the 1800s, was the seed parent in an interspecific hybridization with S. maritima. The sterile F1 hybrid S. xtownsendii gave rise to the fertile allopolyploid S. anglica by chromosomal doubling. Previous chromosome, isozyme, and cpDNA surveys did not reveal notable genetic variation within either the parental or the hybrid species. We used nuclear DNA markers (random amplified polymorphic DNA ([RAPD]) and inter-simple sequence repeats (ISSR) to further explore the origin, diversity, and parentage of S. anglica. We found DNA fragments in S. x townsendii were the aggregate of diagnostic DNA fragments from S. maritima and S. alterniflora, thus confirming its hybrid origin. The S. xtownsendii genotype was identical to most of the S. anglica individuals analyzed, establishing the genetic concordance of these two taxa. We found widespread genetic variation within S. anglica. This could indicate that S. anglica arose several times, from different S. maritima sires. Alternatively, alleles could have been lost through recombination and/or through loss of entire chromosomes in S. anglica. Finally, all but one S. anglica individual had a S. alterniflora component that was indistinguishable from a S. alterniflora plant extant in Marchwood, UK, leaving open the possibility that this plant is the actual seed parent of S. anglica.