Ecology and genetic diversity of the dense-flowered orchid, Neotinea maculata, at the centre and edge of its range

Abstract

Background and Aims Species may occur over a wide geographical range within which populations can display large variation in reproductive success and genetic diversity. Neotinea maculata is a rare orchid of conservation concern at the edge of its range in Ireland, where it occurs in small populations. However, it is relatively common throughout the Mediterranean region. Here, factors that affect rarity of N. maculata in Ireland are investigated by comparing Irish populations with those found in Italy, where it is more common. † Methods Vegetation communities, breeding system and genetic diversity were compared using three amplified fragment length polymorphism (AFLP) primer pairs in populations in Ireland and Italy. Vegetation was quantified using quadrats taken along transects in study populations, and hand pollination experiments were performed to assess reliance of N. maculata on pollinators in both Irish and Italian populations. † Key Results Neotinea maculata occupies different vegetation communities in Italian and Irish populations.Breeding system experiments show that N. maculata is 100 % autogamous, and there are no differences in fruit and seed production in selfed, outcrossed and unmanipulated plants. AFLP markers revealed that Irish and Italian populations have similar genetic diversity and are distinct from each other. † Conclusions Neotinea maculata does not suffer any negative effects of autogamous reproduction; it self-pollinates and sets seed readily in the absence of pollinators. It occupies a variety of habitats in both Ireland and Italy; however, Irish populations are small and rare and should be conserved. This could be due to climatic factors and the absence of suitable soil mycorrhizas to allow recruitment from seed.

Disjunct Populations of a Locally Common North American Orchid Exhibit High Genetic Variation and Restricted Gene Flow

“…Many studies in orchids have reported a lower level of population differentiation than reported in the present study (e.g. [16] [24] [58] [64]. Most of them identified high gene flow between populations through pollen, and/or seed dispersal as the potential causes.…”

Highest genetic diversity at the northern range limit of the rare orchid Isotria medeoloides

“…Numerous subsequent studies have also found low genetic differentiation among orchid populations (for example, Chung et al, 2005;Esfeld et al, 2008;Swarts et al, 2009). Self-fertilization may contribute to the high differentiation of I. medeoloides populations (Hamrick and Godt, 1996), although Neotina maculata, another selfing orchid species, has low population differentiation (Duffy et al, 2009). The tiny and widely separated populations of I. medeoloides may also contribute to its strong genetic structure.…”

Antimicrobial Activity of some Egyptian Citrus Peels Extracts

“…They found that maximum total phenolic content was 53.1 mg GAE/g dry weight by using 5% HCl and this value decreased by using boiling water (38.4) followed by 50% ethanol (25.9), while using cold water the total phenolic content was 15.1 mg GAE/g dry weight. These differences of phenolic content might be due to numerous factors, including types of extraction, kind of solvents ,climatic variables, growing environment, plant age and harvesting time as well as the origin of the sample (Douglas et al, 2004& Duffy et al, 2009). …”