Conservation unit status inferred for plants by combining interspecific crosses and AFLP

Abstract

Hybridization and introgression are common in plants and lead to morphological similarity between species and taxonomic confusion. This gene flow with closely related species can complicate efforts to determine whether an endangered taxon is evolutionarily distinctive and should be identified as a separate conservation unit. Potentilla delphinensis is a rare and threatened endemic species of the Southern French Alps. Two common related taxa (P. grandiflora and P. thuringiaca) are morphologically similar and occur in the same geographical locations. Thus, whether P. delphinensis represents a reliable conservation unit remained unclear. Our evaluation procedure based on a combination of molecular biology and interspecific crosses was used to define taxa within these plants. Plants were sampled from a total of 23 single and mixed localities for the three supposed taxa and were genotyped with 68 polymorphic Amplified Fragment Length Polymorphism (AFLP) loci. Fourty-one seedlings from interspecific crosses were obtained and genotyped. Amplified Fragment Length Polymorphism markers identified four genetically distinct units (P. delphinensis, P. grandiflora and two distinct groups of P. thuringiaca). All individuals of P. delphinensis formed a homogeneous and distinct taxon. This taxon was most probably an old allopolyploid from P. grandiflora and the related group of P. thuringiaca. Interspecific crosses gave low seed set and low germination rate. Furthermore, assignment test indicated that seedlings obtained from interspecific crosses were essentially apomictic rather than hybrids. These results suggest that a reproductive barrier exists between the different taxa. In conclusion, all results supported P. delphinensis as a true biological species and justified its conservation unit status. A surprising outcome of this work was the evidence of a potential new cryptic species. This study demonstrated the need to combine a molecular marker-based approach and pollination experiments for an accurate evaluation of plant taxa

Potentilla—A review of its phytochemical and pharmacological profile

“…The genus Potentilla is well known for its difficulties in identifying species and the frequent synonymies (Nicolè et al, 2007). A common phenomenon within this genus is interspecies hybridization and apomixis.…”

Two new polyploid species closely related to Alnus glutinosa in Europe and North Africa – An analysis based on morphometry, karyology, flow cytometry and microsatellites

“…These morphologically hard to distinguish, yet often reproductively isolated lineages (cryptic taxa; Grant, 1981) represent an important but hidden part of species diversity. The number of recognized cryptic taxa significantly increased during the last decades due to the rapid development of molecular-based taxonomy (e.g., Whittall & al., 2004;Grundt & al., 2006;Nicolè & al., 2007). Many cryptic taxa belong to polyploid plant groups (e.g., Porella L.; Heinrichs & al., 2011;Potentilla L.;Nicolè & al., 2007;Tolmiea Torr.…”

“…The number of recognized cryptic taxa significantly increased during the last decades due to the rapid development of molecular-based taxonomy (e.g., Whittall & al., 2004;Grundt & al., 2006;Nicolè & al., 2007). Many cryptic taxa belong to polyploid plant groups (e.g., Porella L.; Heinrichs & al., 2011;Potentilla L.;Nicolè & al., 2007;Tolmiea Torr. & A.Gray;; Veronica L.; Bardy & al., 2010) and have been recognized thanks to progress in the fields of flow cytometry and molecular biology.…”

Variation in Total Polyphenolics Contents of Aerial Parts of Potentilla Species and Their Anticariogenic Activity

“…A common phenomenon within this genus is interspecies hybridization and apomixis. This has resulted in a great morphological variability of species [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. Extracts from Potentilla species were and are still applied for the treatment of inflammations, wounds, certain forms of cancer, infections due to bacteria, virus or fungi, diarrhoea, diabetes mellitus and several more ailments.…”