The allopolyploid origin ofNarcissus obsoletus(Alliaceae): identification of parental genomes by karyotype characterization and genomicin situhybridization

Abstract

Karyological and genomic in situ hybridization (GISH) approaches provided evidence of the parentage and origin of the hybrid species Narcissus obsoletus. Here, we demonstrate that the putative parental species, N. serotinus L. and N. elegans (Haw.) Spach, recently proposed because of their intermediate morphological traits, have participated in the hybridization process forming this taxon. Karyotype characterization of parental genomes in populations from S Spain and N Morocco has revealed differences in chromosome length and karyotype asymmetry, highlighting their diploid nature. Multicolour GISH on metaphase plates of N. obsoletus, with N. serotinus and N. elegans DNA used as probes, showed differential fluorescent staining of 10 and 20 chromosomes from parental genomes, respectively. Both parental genomes were detected in the allopolyploid, albeit in a duplicated manner. Secondary hybridization between N. obsoletus and N. serotinus was also detected karyologically. Little karyological differentiation between different geographic regions was found in either N. serotinus or N. obsoletus.

Insights into Neogene Mediterranean biogeography based on phylogenetic relationships of mountain and lowland lineages of Narcissus (Amaryllidaceae)

“…Some of the species of most recent origin, such as N . elegans and N. obsoletus , have never been cultivated and show a wide geographical range (Díaz Lifante et al. , 2009).…”

“…, 1999a; Krijgsman, 2002); and the climatic oscillations of the Pleistocene, coupled with sea‐level fluctuations enabling connections between islands (Collina‐Girard, 2001). Different Narcissus groups show very different ecogeographical patterns and speciation processes, which include hybridization and polyploidy in lowland coastal species (Díaz Lifante & Andrés Camacho, 2007; Díaz Lifante et al. , 2009) with largely overlapping ranges (subgenus Hermione ), with some of them (e.g.…”

Population Genetics Methods Applied to a Species Delimitation Problem: Endemic Trumpet Daffodils (NarcissusSectionPseudonarcissi) from the Southern Iberian Peninsula

“…5A), as denoted by the medians of between-group F st values (0.61) being significantly greater than the medians of withingroup F st distributions (0.40). In addition, the virtual absence of admixed individuals in the mountain range where the green and blue groups occur in sympatry (Cazorla-Segura-Las Villas) suggests that despite instances of hybridization being known for this genus (Blanchard 1990;Díaz-Lifante and Andrés-Camacho 2007;Marques et al 2007Marques et al , 2010Díaz-Lifante et al 2009) and the occasional co-occurrence of plants from both groups in adjacent habitats within this area, some type of reproductive isolation between them may be operating. Fifth, the comparison of the relationship between genetic and geographic distances revealed substantial differences between the within-and between-group regression lines ( fig.…”

“…The taxonomy of Narcissus is unsettled and problematic (Webb 1980;Blanchard 1990;Mathew 2002;Zonneveld 2008;Aedo, forthcoming); in particular, the trumpet daffodils (section Pseudonarcissi) are one of the most controversial groups of the genus and are a clear example of the confounding views on both the discrimination of taxa and the assignment of rank (see below). In fact, the reasons for this wide discrepancy among studies may reflect, among other processes, recent phylogenetic divergence, ongoing differentiation, high phenotypic plasticity, hybridization, or some complex combination of these (Pérez- Barrales et al 2006;Díaz-Lifante and Andrés-Camacho 2007;Hodgins and Barrett 2007;Díaz-Lifante et al 2009). Irrespective of the mechanisms responsible for this complexity, however, tracing species boundaries in such complex groups is a challenge unless the patterns and causes of differentiation are assessed.…”

Aneuploids without Bulbils Segregated in F₁ Hybrids Derived from Triploid <i>Lilium lancifolium</i> and Diploid <i>L. leichtlinii</i> Crosses

“…For example, interspecific hybridization between triploid and diploid Lycoris species produced tetraploid hybrids, where unreduced gametes (2n-gametes) in the triploid species were involved in tetraploid production (Ogawa et al, 2006). Unreduced gametes in triploid plants have also contributed to the development of tetraploid cultivars in Narcissus (Lifante et al, 2009) and pentaploid hybrid progenies in the potato (Adiwilaga and Brown, 1991).…”