Stima della biodiversità della dendroflora italiana attraverso il metodo del dna barcoding: il genere quercus
Author(s)
Piredda, Roberta
Date Issued
March 11, 2011
Type
Doctoral Thesis
Abstract
DNA barcoding may be particularly important in influencing ecology, economic issues, and the
fundamental crisis facing biodiversity as a standardized, species-level identification tool for
taxonomy assessment. Trees play important roles in the conservation of many land ecosystems, the
wood trade, and the definition of biogeographical processes; nevertheless, peculiar biological,
evolutionary and taxonomical features will probably constitute an intriguing challenge to barcoders.
We examined whether four marker regions (trnH-psbA, rbcL, rpoC1, matK) proposed by the
Consortium for the Barcode of Life (CBOL) matched species taxonomy in a preliminary tree
biodiversity survey of Italian forested land. Our objective was to provide a test of future in situ
applications of DNA barcodes by evaluating the efficacy of species discrimination under the criteria
of uniformity of methods and natural co-occurrence of the species in the main forest ecosystems.
Fifty-two species were included in a floristic study. We obtained 73% total discrimination success,
with trnH-psbA as the best performing marker and oaks as the least responsive plants to the markers
used. A further taxon-based study of Quercus (thirty specimens, 12 species) revealed that this genus
is refractory to barcoding (0% discrimination success), a probable consequence of low variation rate
at the plastid genome level, hybridization, and the incidence of biogeography. We conclude that
some species-rich tree genera in small geographical regions may prove exceptionally difficult to
barcode. Until more efficient markers are developed, we recommend that improved and diversified
sampling (multiple locations of sympatric and co-occurring congenerics) be embraced as a timely
and important goal for the precise assessment of haplotype specificity to facilitate the productive
application of barcoding in practice.
Additional information
Dottorato di ricerca in Scienze e tecnologie per la gestione forestale e ambientale
File(s)![Thumbnail Image]()
Name
rpiredda_tesid.pdf
Size
5.63 MB
Format
Adobe PDF
Checksum (MD5)
c9f6c173dd5d018ad3119e7ade49b6ef