Isolated and island-like populations at the periphery of a geographic range of a given species are usually predicted to have low genetic diversity due to founder effect, habitat fragmentation, and bottleneck and/or inbreeding. As for parasitic plants, they may be more vulnerable to environmental and demographic stochasticities, habitat degradation, and genetic limitation because of their specialized life-history strategies depending on i.e. host plants. Pedicularis sceptrum-carolinum is a hemiparasitic species with a strongly fragmented geographic range in Eurasia whose small, isolated, island-like populations are scattered at the periphery of its geographic range. I studied its genetic diversity patterns at the western periphery of the species' range (Poland) using AFLP markers in order to unravel how isolation, population size and life-history traits (i.e. type of reproduction) influence its population genetic structure. Despite the geographic isolation among the four investigated populations (ca. 35–350 km), and irrespective of their small population sizes (14–50 individuals) and areas (6–100 m²) they preserved relatively high genetic diversity (Frag_poly= 46.7%-54.6%, Shannon's I = 0.222-0.241) in comparison with other polyploid, long-lived and outcrossing perennials, and significantly higher than that in the other Pedicularis species. Among the factors generating such high genetic diversity is the polyploid origin of this species. Additionally, sexual reproduction, the breeding system, and seed dispersal seem responsible for the patterns of within-population spatial genetic structure. The moderate genetic differentiation among populations (FST = 0.154) and the evidence of recent genetic admixture of populations, as well as genetic similarity among all investigated individuals suggested that gene flow may be relatively high and multi-directional, reflecting recent range expansion of the study species in Europe. I considered that the estimates of genetic differentiation supported the possibility of repeated colonization from different source populations.

Scaphyglottis baudoana Szlach. & Kolan. and S. rangeli Szlach. & Kolan., two new orchid species from Colombia, are described and illustrated. Their taxonomic affinities are discussed and information of their distribution and ecology is provided. They are placed within an identification key to species of the Scaphyglottis fusiformis complex.

Aspidistra australis S.Z. He & W.F Xu sp. nova (Ruscaceae) is described and illustrated from southern Guizhou Province, China. It differs from its closest sibling, A. claviformis, by its leaf blades which are oblong-lanceolate and sparsely serrulate above the middle, by its light yellow perianth, by its stamens being inserted slightly below the middle of the perianth tube, and by its stigma being a little enlarged and with a concave apex.

Psilochilus tuerckheimii Kolan. & Szlach., a new orchid species from Guatemala is described, illustrated and placed within an identification key to the Central American species of Psilochilus. The taxonomic affinity of P. tuerckheimii is briefly discussed.

A new species of Gesneriaceae, Oreocharis jinpingensis W.H. Chen & Y.M. Shui from the Xilong Mountains of Jinping County in southeastern Yunnan, China, bordering North Vietnam, is described and illustrated. Its morphological distinctiveness from the most similar species O. auricula is discussed. Pollen and seed morphological characters are also reported for O. jinpingensis:

The orchid genus Gomphichis, which belongs to the subtribe Prescottiinae, includes approximately 30 species in the Neotropics. The present paper describes and illustrates three new species in the genus: G. schneideri Szlach., S. Nowak & Paluchowska, G. epiphytica Szlach., S. Nowak & Paluchowska and G. renziana Szlach., S. Nowak & Paluchowska. A distribution map of the new species is included along with notes on their habitats. A dichotomous identification key to all Gomphicis species in northern South America is provided. It seems that the new species are endemic in the Cordillera Oriental in the Colombian Andes. The specimens were collected in the Department of Cundinamarca, which includes the Tropical Andes biodiversity hotspot.

Ophiopogon yangshuoensis R.H. Jiang & W.B. Xu (Asparagaceae), a new species from limestone areas in Guangxi, China, is described and illustrated. It is similar to O. intermedius, but differs by its abaxially glaucous leaves, white streaked, broadlanceolate or ovate-lanceolate bracts, narrow-lanceolate innermost bracts, and ovate, reflexed tepals.

Over 30 Prunus species and taxa below the rank of species are known from Iran. These wild taxa provide an enlarged gene pool and may be considered a valuable germplasm source for breeding cultivated almonds. The present study is a genetic diversity analysis of six P. scoparia populations using six nuclear SSR markers. We also studied correlations between the population genetic differences, morphological differences and geographical distance. All six SSR primers produced amplification. The highest number of alleles occurred in the Fars and Lorestan populations, with 121 and 114 alleles, respectively. Some of the alleles were shared by all populations, while some others were specific to one population only. The observed heterozygosity ranged from 0.675 in the Tehran population to 0.900 in the Fars and Lorestan populations, while the expected heterozygosity ranged from 0.783 in the Tehran population to 0.948 in the Fars population. Bayesian model-based clustering showed a good separation of populations at K = 6. AMOVA indicated significant differences both among individuals and among populations. Mantel's test of SSR and morphological trees or geographical distance did not show any distinct pattern. Neighbour-joining and reticulation trees, as well as the STRUCTURE plots revealed admixture among the populations, indicating genetic exchange and presence of ancestral gene loci among them.

Birches are ecologically and economically important trees in forest ecosystems and commonly used in studies of plant—herbivore interactions. Such studies often require manipulation of natural levels of herbivory. In field conditions, this can be executed using insecticides, but such experiments have to assume that the insecticide has no side effects on the study plant. Here we (1) provide results of a test of the effects of synthetic Pyrethrin, deltamethrin, on growth, leaf and litter chemistry and litter decomposition rate of Betula pendula seedlings in controlled growth chamber conditions, and (2) illustrate effectiveness of the insecticide in a field study of the effects of insect herbivory on B. pendula. The field effects, a significant reduction in leaf damage and a corresponding increase in growth, show that we used an effective dose of deltamethrin, while the results of the growth chamber experiment show that the dose did not cause any side effects on B. pendula seedling growth or chemistry. We conclude that Pyrethrin compounds can be safely used for reducing insect-herbivore load on B. pendula in field-scale studies of tree—herbivore interactions.

Sobralia (Orchidaceae) is a genus of about 150 species distributed in Mesoamerica and tropical and subtropical regions of South America. Its species are most often tall plants with single, showy but fugacious flowers. As the result of a morphological study based on herbarium material examined by the authors, Sobralia pakaraimense Baranow & Szlach. from Guyana is described and illustrated as a new species. A key for determination of all Sobralia species reported till now from Guyana is provided.

Dipelta (Caprifoliaceae) is endemic to China, and comprises 3–1 species. Here we used DNA sequences, and SSR and AFLP data to investigate relationships among these taxa. Cluster analysis of all the data showed that D. elegans, an endangered species, was early separated from the others. Both SSR and AFLP data indicated that individuals of D. wenxianensis and D.floribunda were mixed together, suggesting that they were conspecific. STRUCTURE analysis revealed the introgression between D. floribunda and D. yunnanensis, which might produce new “taxa” like D. wenxianensis.