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Background There has always been controversy over whether clonal plants have lower genetic diversity than plants that reproduce sexually. These conflicts could be attributed to the fact that few studies have taken into account the mating system of sexually reproducing plants and their phylogenetic distance. Moreover, most clonal plants in these previous studies regularly produce sexual progeny. Here, we describe a study examining the levels of genetic diversity and differentiation within and between local populations of fully clonal Zingiber zerumbet at a microgeographical scale and compare the results with data for the closely related selfing Z. corallinum and outcrossing Z. nudicarpum. Such studies could disentangle the phylogenetic and sexually reproducing effect on genetic variation of clonal plants, and thus contribute to an improved understanding in the clonally reproducing effects on genetic diversity and population structure. Results The results revealed that the level of local population genetic diversity of clonal Z. zerumbet was comparable to that of outcrossing Z. nudicarpum and significantly higher than that of selfing Z. corallinum. However, the level of microgeographic genetic diversity of clonal Z. zerumbet is comparable to that of selfing Z. corallinum and even slightly higher than that of outcrossing Z. nudicarpum. The genetic differentiation among local populations of clonal Z. zerumbet was significantly lower than that of selfing Z. corallinum, but higher than that of outcrossing Z. nudicarpum. A stronger spatial genetic structure appeared within local populations of Z. zerumbet compared with selfing Z. corallinum and outcrossing Z. nudicarpum. Conclusions Our study shows that fully clonal plants are able not only to maintain a high level of within-population genetic diversity like outcrossing plants, but can also maintain a high level of microgeographic genetic diversity like selfing plant species, probably due to the accumulation of somatic mutations and absence of a capacity for sexual reproduction. We suggest that conservation strategies for the genetic diversity of clonal and selfing plant species should be focused on the protection of all habitat types, especially fragments within ecosystems, while maintenance of large populations is a key to enhance the genetic diversity of outcrossing species.

Cyclocybe parasitica is a wood-destroying parasitic edible mushroom growing on diverse broad-leafed trees in New Zealand and other Pacific areas. Recent molecular systematics of European \(\textit {Cyclocybe aegerita}\), a newly delimited Asian phylum and of related species, corroborated the distinction of the chiefly saprobic cultivated edible mushroom \(\textit {C. aegerita}\) from \(\textit {C. parasitica}\). Here, we show that \(\textit {C. parasitica}\) exhibits a morpho-physiological trait characteristic to its European cousin, i.e., monokaryotic fruiting \(\textit {sensu stricto}\) (basidiome formation without mating). Monokaryotic fruiting structures formed by \(\textit {C. parasitica}\) ICMP 11668-derived monokaryons were categorized into four phenotypes. One of them displays ulcer-like structures previously reported from bracket fungi. Histology of dikaryotic and monokaryotic \(\textit {C. parasitica}\) fruiting structures revealed anatomical commonalities and differences between them, and towards monokaryotic fruiting structures of \(\textit {C. aegerita}\). Mating experiments with \(\textit {C. parasitica}\) strains representative of each fruiting phenotype identified compatible sibling monokaryons. Given reports on hypothetically monokaryotic basidiome field populations of \(\textit {"C. aegerita sensu lato"}\), it seems worthwhile to prospectively investigate whether monokaryotic fruiting s.str. occurs in nature. Sampling from such populations including karyotyping, comparative -omics, and competition assays may help to answer this question and provide evidence whether this trait may confer competitive advantages to a species capable of it.

Cyclocybe parasitica is a wood-destroying parasitic edible mushroom growing on diverse broad-leafed trees in New Zealand and other Pacific areas. Recent molecular systematics of European Cyclocybe aegerita, a newly delimited Asian phylum and of related species, corroborated the distinction of the chiefly saprobic cultivated edible mushroom C. aegerita from C. parasitica. Here, we show that C. parasitica exhibits a morpho-physiological trait characteristic to its European cousin, i.e., monokaryotic fruiting sensu stricto (basidiome formation without mating). Monokaryotic fruiting structures formed by C. parasitica ICMP 11668-derived monokaryons were categorized into four phenotypes. One of them displays ulcer-like structures previously reported from bracket fungi. Histology of dikaryotic and monokaryotic C. parasitica fruiting structures revealed anatomical commonalities and differences between them, and towards monokaryotic fruiting structures of C. aegerita. Mating experiments with C. parasitica strains representative of each fruiting phenotype identified compatible sibling monokaryons. Given reports on hypothetically monokaryotic basidiome field populations of ‘C. aegerita sensu lato’, it seems worthwhile to prospectively investigate whether monokaryotic fruiting s.str. occurs in nature. Sampling from such populations including karyotyping, comparative -omics, and competition assays may help to answer this question and provide evidence whether this trait may confer competitive advantages to a species capable of it.

Paspalum notatum is an important forage native to Southern Brazil and one of the most promising fodder species in terms of productivity, quality, resistance and growth speed. The objective of this study was to evaluate the reproductive mode and fertility of hybrid progenies resulting from artificial crosses among artificially duplicated sexual plants, selected intraspecific hybrids of the UFRGS breeding program and apomictic ecotypes of the species. The resulting F1 progenies were represented by 24 plants with high pollen viability (varying from 82.15 to 99.67%) and 1.2:1 segregation for the sexual: apomictic reproduction mode, indicating predominantly sexual hybrids, due to distorted segregation. In the apomictic plants, most chromosomes paired as bivalents in diakinesis. Since the low presence of abnormalities observed in the meiotic chromosome pairing and the high pollen viability of the hybrids, all plants were confirmed as promising parents for future crosses.

Diverse reproduction modes of bio‐organisms open new intriguing opportunities for biochemistry‐enabled materials. Herein, a new strategy is developed to explore biodirected structures for functional materials via controlling the reproduction mode. Yeast with sexual or asexual reproduction mode are employed in this work. They result in two different biodirected structures, from bowl‐like hollow hemisphere to “bubble‐in‐sphere” (BIS) structure, for the VNxOy/C composites. Benefitting from the hierarchical structure, nanoscale particles and conductive biomass–derived carbon base, both VNxOy/C biocomposites achieve high power/energy density, good reliability, and excellent long‐term cycling stability in aqueous Zn‐ion batteries. Deep investigations further reveal that different biodirected structures greatly influence the electrochemical properties of biocomposites. The bowl‐like structures with thin shells and folded double layers achieve larger surface area and more active sites, which ensure their faster kinetics and better high rate capability. The BIS structures with a more compact assembly and higher stack capability are favorable to the better energy storage. Therefore, this work not only introduces a new clue to boost biodirected structures for functional materials, but also propels the development of Zn‐ion batteries in diverse applications., Herein, a new strategy is developed to boost biodirected structures for functional materials via controlling the reproduction mode. Two different structures of bowl‐like hemisphere and “bubble‐in‐sphere” (BIS) are successfully constructed for VNxOy/C. Different features of diverse biodirected structures ensure the applications of high‐performance VNxOy/C in broad fields.

The longhorn crazy ant, Paratrechina longicornis (Latreille), is a ubiquitous agricultural and urban pest that has invaded most tropical and subtropical regions. Although P. longicornis has been found worldwide for more than a century, the genetic structure, origin, and invasion history of this species have not yet been extensively studied, partially because of the limited number of genetic markers currently available. In the present study, we developed 36 polymorphic microsatellite markers for P. longicornis and characterized these markers by genotyping P. longicornis workers from 74 colonies in East and Southeast Asia. All loci were polymorphic, with the number of alleles per locus ranging from 3 to 18 (8.5 on average). Extremely high levels of heterozygosity were found in all populations, suggesting that workers are invariably produced from the mating of divergent queen and male lineages. Queens and males possess non-overlapping allele size ranges at 18 loci, indicating the potential resolving power of the subset of markers in inferring the history of queen and male lineages. Genetic differentiation among three studied populations was low yet significant and may likely reflect their close association with human activities. Overall, the new microsatellite markers developed in the present study serve as a practical tool to reconstruct routes of invasion and assess the population genetics of this invasive ant.

Some of the most important functional traits in animals are related to the potentially vast array of feeding strategies and microhabitat use. Correlated evolution of diet and habitat specialization with ecomorphological traits has been described in vertebrates, but such functional trait variation in soil in vertebrates is less well-studied. In this study, we explore the evidence for ecomorphological adaptations in Collembola, an important group of soil invertebrates, and place this in the context of their feeding biology, vertical stratification in soil and reproduction mode. For this purpose, we compiled a database of functional traits, including mouthparts structures (mandibula, maxilla), feeding guilds (microbivores, herbivores and scavengers/carnivores), vertical habitat stratification (epigeic, hemiedaphic, euedaphic) and reproduction mode (bisexual, parthenogenetic). We used phylogenetic reconstructions and Pagel's discrete method to test for correlations between various traits. We found a correlation between diet and mandibulae structure, with scavengers/predators possessing scratching/piercing mandibulae without a molar plate, while chewing mandibulae with a molar plate were associated with herbivores and microbivores. Vertical habitat stratification did not correlate to diet or to reproduction mode. No phylogenetic signal was found in the structure of the maxillae, although maxillae in the scavenger/predatory diet group differed structurally from herbivores and/or microbivores. The correlated evolution seen between scavengers/predators and scratching/piercing mandibulae indicate selective pressures linking different morphological traits related to the biology of Collembola, and shed new light on the broader context of diet evolution in soil arthropods.

Meiosis, the key step of sexual reproduction, persists in facultative apomictic plants functional to some extent. However, it still remains unclear how and why proportions of reproductive pathways vary under different environmental stress conditions. We hypothesized that oxidative stress mediates alterations of developmental pathways. In apomictic plants we expected that megasporogenesis, the stage directly after meiosis, would be more affected than later stages of seed development. To simulate moderate stress conditions we subjected clone-mates of facultative apomictic Ranunculus auricomus to 10 h photoperiods, reflecting natural conditions, and extended ones (16.5 h). Reproduction mode was screened directly after megasporogenesis (microscope) and at seed stage (flow cytometric seed screening). Targeted metabolite profiles were performed with HPLC–DAD to explore if and which metabolic reprogramming was caused by the extended photoperiod. Prolonged photoperiods resulted in increased frequencies of sexual vs. aposporous initials directly after meiosis, but did not affect frequencies of sexual vs. asexual seed formation. Changes in secondary metabolite profiles under extended photoperiods affected all classes of compounds, and c. 20% of these changes separated the two treatments. Unexpectedly, the renowned antioxidant phenylpropanoids and flavonoids added more to clone-mate variation than to treatment differentiation. Among others, chlorophyll degradation products, non-assigned phenolic compounds and more lipophilic metabolites also contributed to the dissimilarity of the metabolic profiles of plants that had been exposed to the two different photoperiods. The hypothesis of moderate light stress effects was supported by increased proportions of sexual megaspore development at the expense of aposporous initial formation. The lack of effects at the seed stage confirms the basic assumption that only meiosis and sporogenesis would be sensitive to light stress. The concomitant change of secondary metabolite profiles, as a systemic response at this early developmental stage, supports the notion that oxidative stress could have affected megasporogenesis by causing the observed metabolic reprogramming. Hypotheses of genotype-specific responses to prolonged photoperiods are rejected. Open-Access Publikationsfonds 2016 peerReviewed

The study aimed to determine the long-term changes of the Senecio macrophyllus M.BIEB. population traits: the abundance, reproduction mode, individual fecundity, seed rain and recruitment of new genets in the course of xerothermic grassland overgrowing. The study had also the applied goal: to estimate the chances of "special care" species to survive in the changing environment without management regime for the maintenance of grassland. The model object was the island population of large-leaved ragwort on Biała Góra (the White Mountain) near Tomaszów Lubelski, South-East Poland. To achieve these aims I used the following sets of data: phytosociological relev,s made in plant communities in an interval of 16-18 years; repeated elaboration of the numbers and life-stage structure of the population, both by non-surface and surface method; observation of plants, life cycle in 50 labelled genets; population reproduction and seed rain amounts. The area of an open xerothermic grassland decreased due to the process of overgrowing by bushes which was accompanied by the increasing coverage of forest and meadow herbs as well as monocotyledons, mainly Brachypodium pinnatum and Calamagrostis epigejos. The abundance of the S. macrophyllus population noticable diminished. The flowering mode has been changing during years from an oscillation to a chaotic type which caused the significant decreasing of the individual fecundity, population reproduction and seed rain. In last years it was reflected in the interruption of juveniles’ recruitment.

For evolutionary studies of polyploid species estimates of the genetic identity between species with different degrees of ploidy are particularly required because gene counting in samples of polyploid individuals often cannot be done, e.g., in triploids the phenotype AB can be genotypically either ABB or AAB. We recently suggested a genetic distance measure that is based on phenotype counting and made available the computer program POPDIST. The program provides maximum-likelihood estimates of the genetic identities and distances between polyploid populations, but this approach is not informative for populations within species that only differ in their allele frequencies. We now close this gap by applying the frequencies of shared 'bands' in both populations to Nei's identity measure. Our simulation study demonstrates the close correlation between the band-sharing identity and the genetic identity calculated on the basis of gene frequencies for any degree of ploidy. The new extended version of POPDIST (version 1.2.0) provides the option of choosing either the maximum-likelihood estimator or the band-sharing measure.

Background and Aims Allopolyploidy and intraspecific heteroploid crosses are associated, in certain groups, with changes in the mating system. The genus Sorbus represents an appropriate model to study the relationships between ploidy and reproductive mode variations. Diploid S. aria and tetraploid apomictic S. austriaca were screened for ploidy and mating system variations within pure and sympatric populations in order to gain insights into their putative causalities. Methods Flow cytometry was used to assess genome size and ploidy level among 380 S. aria s.l. and S. austriaca individuals from Bosnia and Herzegovina, with 303 single-seed flow cytometric seed screenings being performed to identify their mating system. Pollen viability and seed set were also determined. Key Results Flow cytometry confirmed the presence of di-, tri- and tetraploid cytotype mixtures in mixed-ploidy populations of S. aria and S. austriaca. No ploidy variation was detected in single-species populations. Diploid S. aria mother plants always produced sexually originated seeds, whereas tetraploid S. austriaca as well as triploid S. aria were obligate apomicts. Tetraploid S. aria preserved sexuality in a low portion of plants. A tendency towards a balanced 2m : 1p parental genome contribution to the endosperm was shared by diploids and tetraploids, regardless of their sexual or asexual origin. In contrast, most triploids apparently tolerated endosperm imbalance. Conclusions Coexistence of apomictic tetraploids and sexual diploids drives the production of novel polyploid cytotypes with predominantly apomictic reproductive modes. The data suggest that processes governing cytotype diversity and mating system variation in Sorbus from Bosnia and Herzegovina are probably parallel to those in other diversity hotspots of this genus. The results represent a solid contribution to knowledge of the reproduction of Sorbus and will inform future investigations of the molecular and genetic mechanisms involved in triggering and regulating cytotype diversity and alteration of reproductive modes.

The high proportion of brooding (50 to 70% depending on phyla) compared with broadcaster species among invertebrates living along the coast of the Southern ocean has been traditionally interpreted as an adaptation to local environmental conditions. Currently, however, species with a planktotrophic developmental mode are ecologically dominant along coastal areas, in terms of abundance of individuals. The fact that Kerguelen island is inhabited by such species and that the French base Port-aux-Français, with its equipped marine laboratory, made it possible to address questions as to why are there so many brooders in the coastal waters of the Southern ocean and if the apparent ecological success of broadcasters related to their developmental mode. We argue that the present shallow antarctic benthic invertebrate fauna is the result of two processes acting at different temporal scales. First, the high proportion of brooding species compared with coastal communities elsewhere corresponds to species-level selection occurring over geological and evolutionary times which explains the very high biodiversity observed in coastal waters. Second, the ecological dominance of broadcasters is the result of processes operating at ecological timescales that are associated with the advantage of having pelagic larvae under highly disturbed conditions (e.g., ice scouring). rÉsUMÉ.-les îles Kerguelen : un laboratoire vivant pour la compréhension de la biodiversité benthique en antarctique. la proportion élevée (50 à 70% selon les phylums) d'espèces incubantes comparée à celle des espèces dispersantes d'invertébrés vivant dans les eaux côtières de l'océan austral a été traditionnellement interprétée comme une adaptation aux conditions environnementales locales. Cependant, de nos jours, les espèces à développement planctotrophique y sont écologiquement dominantes, en termes d'abondance. le fait que les îles Kerguelen abritent de telles espèces et que la base de Port-aux-Français possède un véritable laboratoire marin a permis de développer des programmes pour répondre à des questions comme : pourquoi y-at -il tant d'espèces incubantes dans les eaux côtières de l'océan austral ? ou bien, le suc-cès écologique apparent des espèces dispersantes est-il lié à leur mode de développement ? nous soutenons que la faune actuelle d'invertébrés benthiques côtiers antarctiques est le résultat de deux processus agissant à des échelles temporelles différentes : (1) la proportion élevée d'espèces incubantes, comparée aux communautés côtières partout ailleurs, correspond à une sélection au niveau de l'espèce se produisant à des échelles de temps géologiques qui explique la biodiversité très élevée observée dans les eaux côtières, (2) la dominance écologique actuelle des espèces dispersantes est le résultat de processus fonctionnant à des échelles de temps écologiques qui sont associés à l'avantage de posséder des larves pélagi-ques dans des conditions fortement perturbées (p. ex., rabotage des fonds par les icebergs). Since the seventies, benthic biodiversity was assessed in Kerguelen during the cruises of the Marion Dufresne and thanks to programs by r. Delépine and others focused on algae, P. arnaud, a. Guille, J.-P. Féral on macrobenthos and by J.-C. Hureau and G. Duhamel on fishes. Pioneering efforts to study the antarctic biodiversity in Terre adélie were conducted by P. arnaud and J.-C. Hureau in the early sixties and in 1987 by the first diving expedition by J.-P. Féral. Initial investigations of antarctic marine biology started with mac-robenthos and fishes. The use of scuba diving, limited exploration only until 30 m depth; the use of a remote operated vehicle (roV) in 2000 permitted the study of biodiversity at 150 m depth. The Astrolabe, equipped with a ROV, verified previous observations. Contrary to an accepted (continental-based) paradigm that biodiversity declines from the equator to the poles, marine biodiversity, at least coastally, is very high along the antarctic continent and the sub-antarctic islands. as the observed biodiversity at a time is the result of the histories of the species, of the climate and of the ocean basins, it is necessary to consider different time scales to understand the present biodiversity. To only compare contemporary conditions with the characteristics of the fauna and flora is quite risky. Hence, we propose to first consider exceptional biological properties of the antarctic fauna, using model species ., La proportion élevée (50 à 70% selon les phylums) d’espèces incubantes comparée à celle des espèces dispersantes d’invertébrés vivant dans les eaux côtières de l’océan Austral a été traditionnellement interprétée comme une adaptation aux conditions environnementales locales. Cependant, de nos jours, les espèces à développement planctotrophique y sont écologiquement dominantes, en termes d’abondance. Le fait que les îles Kerguelen abritent de telles espèces et que la base de Port-aux-Français possède un véritable laboratoire marin a permis de développer des programmes pour répondre à des questions comme : pourquoi y-a-t-il tant d’espèces incubantes dans les eaux côtières de l’océan Austral ? Ou bien, le suc-cès écologique apparent des espèces dispersantes est-il lié à leur mode de développement ? Nous soutenons que la faune actuelle d’invertébrés benthiques côtiers antarctiques est le résultat de deux processus agissant à des échelles temporelles différentes : (1) la proportion élevée d’espèces incubantes, comparée aux communautés côtières partout ailleurs, corres-pond à une sélection au niveau de l’espèce se produisant à des échelles de temps géologiques qui explique la biodiversité très élevée observée dans les eaux côtières, (2) la dominance écologique actuelle des espèces dispersantes est le résultat de processus fonctionnant à des échelles de temps écologiques qui sont associés à l’avantage de posséder des larves pélagi-ques dans des conditions fortement perturbées (p. ex., rabotage des fonds par les icebergs).

Background Hybridisation is presumed to be an important mechanism in plant speciation and a creative evolutionary force often accompanied by polyploidisation and in some cases by apomixis. The Potentilla collina group constitutes a particularly suitable model system to study these phenomena as it is morphologically extensively variable, exclusively polyploid and expresses apomixis. In the present study, the alpine taxon Potentilla alpicola has been chosen in order to study its presumed hybrid origin, identify underlying evolutionary processes and infer the discreteness or taxonomic value of hybrid forms. Results Combined analysis of AFLP, cpDNA sequences and ploidy level variation revealed a hybrid origin of the P. alpicola populations from South Tyrol (Italy) resulting from crosses between P. pusilla and two cytotypes of P. argentea. Hybrids were locally sympatric with at least one of the parental forms. Three lineages of different evolutionary origin comprising two ploidy levels were identified within P. alpicola. The lineages differed in parentage and the complexity of the evolutionary process. A geographically wide-spread lineage thus contrasted with locally distributed lineages of different origins. Populations of P. collina studied in addition, have been regarded rather as recent derivatives of the hexaploid P. argentea. The observation of clones within both P. alpicola and P. collina suggested a possible apomictic mode of reproduction. Conclusions Different hybridisation scenarios taking place on geographically small scales resulted in viable progeny presumably stabilised by apomixis. The case study of P. alpicola supports that these processes played a significant role in the creation of polymorphism in the genus Potentilla. However, multiple origin of hybrids and backcrossing are considered to produce a variety of evolutionary spontaneous forms existing aside of reproductively stabilised, established lineages.