Contribuţii Botanice - 2010, XLV: 7-12 Grădina Botanică “Alexandru Borza” Cluj-Napoca THE POA GRANITICA GROUP IN THE CARPATHIAN MOUNTAINS: SOME MOLECULAR INSIGHTS Ioan BĂCILĂ 1 , Dana ŞUTEU 1 , Ana COSTE 1 , Liviu FILIPAŞ 1 , Tudor URSU 1 , Ilie-Adrian STOICA 1 , Bogdan-Iuliu HURDU 1 , Mihai PUŞCA޲, Gheorghe COLDEA 1 1 Institutul de Cercetări Biologice, str. Republicii, nr. 48, RO-400015 Cluj-Napoca, Romania 2 Universitatea Babeş-Bolyai, Grădina Botanică A. Borza, str. Republicii, nr. 42, RO-400015 Cluj-Napoca, România e-mail: suteudana@yahoo.com Abstract: Poa deylii Chartek & Jirasek is a grass taxon endemic to the South-Eastern Carpathians, which is of unclear taxonomic status, with no molecular research on the structure of its populations. Many authors have considered, based on morphological traits, this taxon to be a valid species or a subspecies included within P. granitica Br.-Bl. In the present study we have used three molecular markers – one nuclear (ITS1) and two chloroplastic (introns trnG and trnL) – to explore the variability within the P. granitica group. No genetic difference was detected, in spite of the morphological variation that distinguishes these two taxa (P. granitica subsp. granitica and P. deylii). Other approaches, such as the AFLP technique, that address the entire genome, might be required for a better understanding of the genetic variation within this group. Keywords: Poa granitica group, taxonomy, endemic species, cpDNA, ITS Introduction The genus Poa includes annual and perennial grass species native to temperate regions of both hemispheres. The genus Poa belongs to the Pooideae subfamily of the family Poaceae [1]. The Poa granitica group comprises two distinct taxonomic units: P. granitica Br.-Bl. and Poa deylii Chrtek & Jirasek. The morphological differences between them are minute and both have approximately the same habitat preferences (alpine and subalpine acidophilic communities of Salicion herbaceae) [2, 7]. The taxonomic history of the group is obscure because P. deylii has been ascribed to different taxonomic categories (var. disparilis Nyar., subsp. disparilis (Nyar.) Nyar.), reviewed by Filipaş et al. (2009) [3]. Due to the low level of morphological differentiation, the presence of both taxa in the South-Eastern Carpathians was questionable. Filipaş et al. (2009) pointed out that P. granitica is not present in the flora of the SE Carpathians, being endemic to the Western Carpathians. Also the authors clarified the chorology of P. deylii. The presence of P. deylii is certified through herbarium material in the following massifs: Bucegi, Făgăraş, Maramureş, Retezat, Iezer and Rodna Mountains. In this last mountain range the species is more frequent and abundant then in the other parts of the SE Carpathians. Molecular markers have proved a powerful tool to resolve many taxonomic issues, especially where the morphological boundaries between very close taxa are obscure or critical [4, 8, 9, 10, 12, 13]. The main goal of this present study has been to investigate whether there is a genetically sound basis for supporting Poa deylii as a distinct taxonomic unit. Furthermore, we aim to identify a molecular marker polymorphic enough to discriminate between P. granitica and P. deylii and to investigate taxonomic boundaries within the P. granitica–P. deylii group in the SE Carpathians.