Genetic variability of Eurasian Nuphar species unravels possible routes in which freshwater plants could fill their wide areas

Genetic Diversity and Population Structure Assessed Using Microsatellite (SSR) Markers from Relict Populations of Nuphar pumila (Nymphaeaceae)

“…However, a recent study by Volkova et al [6] based on nuclear and plastid makers, which focused on the east European and central and east Asian populations, suggest that the hybridization between the two species is not as common as previously thought based on morphology, e.g., [3,15,37]. Moreover, Nuphar × spenneriana has been suggested to be capable of displacing either of its parental species depending on the scenario [6,8].…”

“…(1821) [3,5]. These closely related species, which have been reported to be genetically and morphologically similar [1,6], display different ecological preferences linked to factors, such as water temperature, altitude and water depth, that determine their distribution ranges [5,[7][8][9]. Thus, N. lutea is a more generalist species that inhabits warmer waters and tolerates higher salinity, moderately eutrophic habitats and water movements, while N. pumila-which is considered to be part of the "boreal-alpine glacial relicts"-prefers higher altitudes at southern latitudes (e.g., the Alps, Jura, and Vosges), not very deep colder acid waters of mountain lakes, and oligotrophic and dystrophic habitats [3,5,[7][8][9][10].…”

“…Both species are distributed through the lakes of Eurasia, being widespread in northern latitudes [6,[11][12][13]. However, while N. lutea occupies vast territories in southern latitudes extending from the British Islands and the Mediterranean basin in the West-including the Balkans and most the Italic and Iberian Peninsulas-to China and Japan in the East [3,4,[14][15][16][17], the southern distribution of N. pumila comprises a series of relict populations confined to the British Islands and European mountainous areas of the Alps, the French Massif Central and the Cantabrian Mountains (North Spain) in the West, and the northern lakes of Mongolia, east China and Japan in the East [3,4,6,9,14,15,[18][19][20][21][22]. In recent decades, many N. pumila populations in their natural range have been reported to have disappeared due to hybridization with N. lutea-which generates the fertile hybrid Nuphar × spenneriana Gaudin-and Nuphar japonica DC.…”

“…In this sense, the disappearance of populations in recent decades reported in Central Europe has been correlated with the displacement by the hybrid Nuphar × spenneriana using microsatellites, thus suggesting that the presence of this hybrid is one of the major threats for the survival of N. pumila in the area [5,9,10]. However, a recent study by Volkova et al [6] based on nuclear and plastid makers, which focused on the east European and central and east Asian populations, suggest that the hybridization between the two species is not as common as previously thought based on morphology, e.g., [3,15,37]. Moreover, Nuphar × spenneriana has been suggested to be capable of displacing either of its parental species depending on the scenario [6,8].…”

Glacial relicts in the Alps: the decline and conservation strategy for Nuphar pumila (Nymphaeaceae)

“…In the Alps, hybridization with N. lutea has been described as one of the main threats to the natural populations of N. pumila (Arrigo et al 2016). Surprisingly, hybridization seems to be very rare in Eastern Europe and Asia (Volkova et al 2018).…”