Most flowering plants, including important crops, require double fertilization to form an embryo and endosperm, which nourishes it. Independence from fertilization is a feature of apomictic plants that produce seeds, from which the plants that are clones of the mother plant arise. The phenomenon of apomixis occurs in some sexual plants under specific circumstances. Since the launch of a fertilization-independent mechanism is considered a useful tool for plant breeding, there have been efforts to artificially induce apomixis. We have been able to produce fertilization-independent endosperm in vitro in Arabidopsis over the last few years. This paper demonstrates the methods of improving the quality of the endosperm obtained using plant and mammalian steroid hormones. Additionally, it shows the study on the autonomous endosperm (AE) formation mechanism in vitro.This paper examines the effect of exogenous steroid hormones on unfertilized egg and central cell divisions in culture of unpollinated pistils of Arabidopsis Col-0 wild-type and fie-1 mutant. All media with hormones used (estrone, androsterone, progesterone, and epibrassinolide) stimulated central cell divisions and fertilization-independent endosperm development. The stages of AE development followed the pattern of Arabidopsis thaliana wild type after fertilization. Subsequent stages of AE were observed from 2-nuclear up to cellular with the most advanced occurring on medium with 24-epibrassinolide and progesterone. The significant influence of mammalian sex hormones on speed of AE development and differentiation was noticed. Using restriction analysis, the changes in methylation of FIE gene was established under in vitro condition. The authors of this paper showed that Arabidopsis thaliana has a high potency to fertilization-independent development.

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Current and expected changes in global climate are major threat for biological diversity affecting individuals, communities and ecosystems. However, there is no general trend in the plants response to the climate change. The aim of present study was to evaluate impact of the future climate changes on the distribution of holomycotrophic orchid species using ecological niche modeling approach. Three different scenarios of future climate changes were tested to obtain the most comprehensive insight in the possible habitat loss of 16 holomycotrophic orchids. The extinction of Cephalanthera austiniae was predicted in all analyses. The coverage of suitable niches of Pogoniopsis schenckii will decrease to 1–30% of its current extent. The reduction of at least 50% of climatic niche of Erythrorchis cassythoides and Limodorum abortivum will be observed. In turn, the coverage of suitable niches of Hexalectris spicata, Uleiorchis ulaei and Wullschlaegelia calcarata may be even 16–74 times larger than in the present time. The conducted niche modeling and analysis of the similarity of their climatic tolerance showed instead that the future modification of the coverage of their suitable niches will not be unified and the future climate changes may be not so harmful for holomycotrophic orchids as expected.

Polish Arabian horses are one of the most important populations of this breed in the world. Their post-war history can be divided into two periods, with the dominant role of state studs until 1989, and the increasing significance of private breeding in the next years. The goal of the study was to evaluate genetic diversity and structure of the population under a new breeding policy. The analyses of breeding and microsatellite data from 1996 to 2012 provide a coherent picture of the population with constant flow of horses only in one direction from state to private studs. An increase in the number of broodmares was observed, from 396 mares in 1996 to 1021 mares in 2012. The proportion of foreign sires used in Polish studs also increased, from 7.1% to 37.0%. An increasing number of alleles and progressive differentiation in mares were observed. STRUCTURE analysis indicated that the Polish horses were clearly separated from foreign horses used in Polish breeding, although only one of the 75 alleles found can be considered as typically Polish. The high heterozygosity is an important feature of the Polish population; however, the decrease of heterozygosity in state broodmares was noted. This issue needs to be studied further.

BackgroundThe generic separateness and specific composition of the orchid genus Cyrtochilum was discussed for almost two centuries. Over the years several smaller taxa were segregated from this taxon, but their separateness was recently questioned based on molecular studies outcomes. The aim of our study was to revise concepts of morphological-based generic delimitation in Cyrtochilum-alliance and to compare it with the results of genetic analysis. We used phylogenetic framework in combination with phenetical analysis to provide proposal of the generic delimitation within Cyrtochilum-alliance. Two molecular markers, ITS and matK were used to construct phylogenetic tree. A total of over 5000 herbarium specimens were included in the morphological examination and the phenetical analysis included 29 generative and vegetative characters.ResultsComparative morphology of the previously recognized genera: Buesiella, Dasyglossum, Neodryas, Rusbyella, Siederella and Trigonochilum is presented. A new species within the the latter genus is described. Fourteen new combinations are proposed. The key to the identification of the genera of the Cyrtochilum-alliance and morphological characteristics of each genus are provided.ConclusionsA total of six separated genera are recognized within Cyrtochilum-alliance. The reasons of the incompatibility between morphological differences observed within studied taxa and phylogenetic tree are argued and the taxonomic implications of such inconsistency, resulting in fragmentation or lumping of taxonomic units, are discussed.Electronic supplementary materialThe online version of this article (doi:10.1186/s40529-017-0164-z) contains supplementary material, which is available to authorized users.

The intensively discussed taxonomic complexity of the Dactylorhiza genus is probably correlated with its migration history during glaciations and interglacial periods. Previous studies on past processes affecting the current distribution of Dactylorhiza species as well as the history of the polyploid complex formation were based only on molecular data. In the present study the ecological niche modeling (ENM) technique was applied in order to describe the distribution of potential refugia for the selected Dactylorhiza representatives during the Last Glacial Maximum. Additionally, future changes in their potential habitat coverage were measured with regard to three various climatic change scenarios. The maximum entropy method was used to create models of suitable niche distribution. A database of Dactylorhiza localities was prepared on the grounds of information collected from literature and data gathered during field works. Our research indicated that the habitats of majority of the studied taxa will decrease by 2080, except for D. incarnata var. incarnata, for which suitable habitats will increase almost two-fold in the global scale. Moreover, the potential habitats of some taxa are located outside their currently known geographical ranges, e.g. the Aleutian Islands, the western slopes of the Rocky Mountains, Newfoundland, southern Greenland and Iceland. ENM analysis did not confirm that the Balkans, central Europe or central Russia served as the most important refugia for individual representatives of the Dactylorhiza incarnata/maculata complex. Our study rather indicated that the Black Sea coast, southern Apennines and Corsica were the main areas characterized by habitats suitable for most of the taxa.

To gain an overview of the variation in the Dactylorhiza incarnata/maculata complex in northern Poland, ten plastid DNA regions (seven microsatellite and three indel loci) and 23 morphometric characters were used. In total, 972 and 480 samples from 64 and 31 populations were utilized for the genetic and morphometric analyses, respectively. One hundred and forty‐one haplotypes that have not been reported previously were recognized. The continuity of morphological characters between the studied species and the impact of post‐glacial colonization on the observed complexity in the Dactylorhiza incarnata/maculata complex were concluded. It was confirmed that the allotetraploid group of D. majalis s.s. has inherited its plastid genome from D. maculata s.l., specifically from D. maculata ssp. fuchsii. In addition, some of the haplotypes found in D. majalis s.s. were distinct and evidently not present in the preserved D. maculata s.l. Although possible gene flow and introgression between two subspecies of the D. maculata s.l. group were indicated, we suggest that they should be treated as separate evolutionary units. Both the common and rare haplotypes show a similar pattern of geographical distribution for all four taxa analysed, which suggests that hybridization took place relatively recently, shortly after the retreat of the ice sheet. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178, 121–137.

The results of a revision of the orchid genus Andinia are presented. The proposed classification is based on outcomes of morphological and molecular studies. Additionally, the similarity of the climatic niches occupied by representatives of the Andinia-complex was calculated and visualized. The highest number of Andinia representatives is found in the Eastern Cordillera real montane forests, while Neooreophilus species are found in two ecoregions—the Eastern Cordillera real montane forests, and the Northwestern Andes. According to the level of endemism, a very unique orchid flora was noted in the Guajira–Barranquilla xeric scrub ecoregion, as well as in the Isthmian-Pacific and the Ucayali moist forests, where single endemic species occur. In the proposed classification, nine genera are recognized within the Andinia-complex, three of which (Xenosiella, Chicalia, and Minuscula) are described in this paper. A key to the identification of all genera is provided. Additionally, sections Amplectentes and Bilamellatae of Neooreophilus are elevated to the subgeneric rank, and subgenus Aenigma is here considered as a separate genus. A complete list of representatives of each taxon is provided, and new combinations are proposed accordingly. A new species of Neooreophilus from Colombia is described.