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The range of ecological CSR strategies for subalpine tall-herb communities of the northwestern Caucasus (Teberda state natural biosphere reserve) has been studied by the measurement of leaves’ functional traits. These communities are developed in swales, river valleys, and runoff depressions of the subalpine belt and represent a typical element of the Caucasian flora. The dominating species are represented by tall forbs, such as Rumex alpinus, Senecio platyphylloides, Cephalaria gigantea, Ligusticum alatum, etc. To evaluate ecological strategies of plants, three functional traits, including leaf area and the weights of wet and dry leaves, have been measured. Based on these measurements, the strategy parameters have been calculated for 42 vascular plant species. The majority of plants of the subalpine tall-grass community manifest traits typical for the competitive (C) and competitive-ruderal (CR) strategies. According to the calculation algorithm, 11 species (Angelica purpurascens, A. tatianae, Cirsium chlorocomos, Heracleum asperum, H. leskovii, H. sosnowskyi, etc.) are referred to the C-strategy. The CR strategy is observed for Aconitum nasutum, Cirsium simplex, Geranium sylvaticum, Hesperis voronovii, Rumex alpestris, and some other species. Two species (Achillea millefolium and Dactylis glomerata) are characterized by the competitive and stress-tolerant (CS) strategy. The stress-tolerant (S) strategy is observed for three species (Veronica filiformis, Lilium monadelphum, and Millium effusum). Finally, the mixed CSR strategy is typical for two species (Trifolium pratense and Astrantia maxima). The majority (93%) of the species studied is characterized by clear competitive traits; the contribution of this strategy type positively correlates with the average vegetative height of a species. In addition, many of the studied species (26% on average) are also characterized by some R-strategy traits. In our opinion, this fact results from a long-term grazing history of alpine plant communities in this region. The obtained results contradict the common opinion about the domination of stress-tolerant species in highlands. This contradiction may be explained by the fact that the studied subalpine meadows are located in the most favorable habitats providing competitive advantages for rapidly-growing tall-herb species. The study confirms the hypothesis that the dominated species of the subalpine tall-grass community of the northwest Caucasus are characterized by significantly (up to 95%) manifested traits of C strategy.

Both temperature and flower colour have major effects on the foraging of pollinators. Despite both factors being important, no studies have examined the interactive effects of temperature and colour and how this may impact the maintenance of natural floral colour polymorphisms. We tested how temperature influenced bumblebees (Bombus spp.) visitation rates to Geranium sylvaticum (Linnaeus 1753) plants both in a greenhouse and field settings. G. sylvaticum shows colour polymorphism among populations, and individuals can be classified into two discrete morphs, dark morphs or pale morphs based on their visible light. We found that bumblebee visitation rates to plants and flowers increased linearly with temperature in the greenhouse and in the field, before decreasing at the highest temperatures in the greenhouse. In the greenhouse, there was an increasing preference for dark morphs at 23-26oC, whereas dark morphs received more visits than pale morphs at all temperatures. Temperature-related differences in reward quality along with differences between colour morphs are likely to drive this pattern, though other mechanisms could be important.

• In gynodioecious plants, females are expected to produce more or better seeds than hermaphrodites in order to be maintained within the same population. Even though rarely measured, higher seed production can be achieved through differences in physiology. • In this work, we measured sexual dimorphism in several physiological traits in the gynodioecious plant Geranium sylvaticum. Photosynthetic rate, stomatal conductivity, transpiration rate, water use efficiency and isotopic signatures were measured in plants growing in two habitats differing in light availability. • Females have been reported to produce more seeds than hermaphrodites. However, we did not observe any significant difference in seed output between the sexes in these experimental populations. Similarly, the sexes did not differ in any physiological trait measured. Seed production was strongly limited by light availability. Likewise, differences between plants growing in full light vs. low light were detected in most physiological parameters measured. • Our results show that the sexes in G. sylvaticum do not show any evidence of sexual dimorphism in physiology which concurred with the lack of sexual differences in seed output.

Resource allocation trade-offs between sexual functions are predicted, but these are usually measured only at the whole plant level. In some gynodioecious species, individuals with partially restored male fertility exist providing an opportunity to investigate whether the costs associated with male fertility restoration are linked to seed production. In this study, we examined whether there is a relationship between the numbers of stamens and seeds produced both at the flower level and at the plant level in the gynodioecious herb Geranium sylvaticum. We individually marked flowers in plants varying in the degree of male sterility in the field and counted the number of seeds produced. There was no significant correlation between the numbers of stamens and seeds produced at the flower level suggesting an absence of resource trade-off between female and male functions. Furthermore, the numbers of stamens and seeds were positively correlated at the plant level. The lack of trade-offs between the two sexual functions in this species indicates that relative sex allocation was not affected by resources within a single season and/or that the male costs were relatively small.

tIn gynodioecious plants females need a reproductive advantage over hermaphrodites to be maintainedin the same population. Generally, three main proximate causes for a female advantage are considered:inbreeding avoidance, different resource allocation patterns, and differences in ecological interactions.A mechanism potentially causing a female advantage that is rarely discussed is a difference in flo-ral longevity between the genders. Females may have a longer stigma lifespan than hermaphrodites,which can affect pollination. Stigma and flower lifespan are rarely documented in gynodioecious species,although it is a common observation in dioecious species that female plants flower longer than males.Here we focus on the stigma and flower lifespan of gynodioecious Geranium sylvaticum, which couldpotentially contribute to the female advantage observed in this and other closely related species. Wemeasured the stigma and flower lifespan in unpollinated flowers of female, hermaphrodite and plantswith an intermediate gender expression. Our results show that stigma lifespan is almost twice as long infemales as in hermaphrodites and intermediate plants. Also flower lifespan is longest in females. We dis-cuss the potential mechanisms through which an increased floral lifespan can lead to a female advantagedespite the generally lower pollinator visitation rates observed in females by reviewing available studies.Our study shows that increased floral persistence in females can be an important aspect in the mainte-nance of females in gynodioecious plants and should be taken into account as a potential proximate causefor a female advantage.

The seasonal variation of polyphenols in the aboveground organs and roots of Geranium sylvaticum in four populations was studied using UPLC-DAD-ESI-QqQ-MS/MS. The content of the main compound, geraniin, was highest (16% of dry weight) in the basal leaves after the flowering period but stayed rather constant throughout the growing season. Compound-specific mass spectrometric methods revealed the different seasonal patterns in minor polyphenols. Maximum contents of galloylglucoses and flavonol glycosides were detected in the small leaves in May, whereas the contents of further modified ellagitannins, such as ascorgeraniin and chebulagic acid, increased during the growing season. In flower organs, the polyphenol contents differed significantly between ontogenic phases so that maximum amounts were typically found in the bud phase, except in pistils the amount of gallotannins increased significantly in the fruit phase. These results can be used in evaluating the role of polyphenols in plant-herbivore interactions or in planning the best collection times of G. sylvaticum for compound isolation purposes.

In the UK, upland hay meadows (Anthoxanthum odoratum–Geranium sylvaticum grassland) with high plant biodiversity are rare and confined to submontane areas of northern England. We report results from a 5-year experiment to test suggestions that recent biodiversity declines were attributable to increased sheep-stocking density and a longer spring stocking period, thus delaying the shut up date for the growth of the hay crop. Longer stocking periods and higher stocking densities decreased the forage mass at 8 July, but they increased herbage N content and digestibility, reduced plant species diversity and reduced populations and seed production of Rhinanthus minor. Compared with unstocked swards, the similarity of the vegetation to Anthoxanthum odoratum–Geranium sylvaticum grassland was reduced by 16·9% when stocking with sheep continued until 27 May each year, and by 8·3% when sward heights were maintained at 3 cm compared with 5 cm. Increased mean sward height and height of R. minor were positively correlated with accumulated temperatures. Results support suggestions that recent reductions in the nature value of these grasslands might be a consequence of high stocking densities persisting until later in the spring, carried out during a 1-year period with warmer temperatures.

Four hydrolysable tannins, named as sylvatiins A (1), B (2), C (3) and D (4), were isolated from the petals of Geranium sylvaticum. On the basis of spectrometric evidence of NMR analysis ((1)H NMR, (13)C NMR, DQF-COSY, TOCSY, NOESY, HSQC and HMBC), circular dichroism (CD) and ESI-MS/MS, sylvatiins A, B and C were characterized as galloyl glucoses containing one or two acetylglucoses attached to the 3-OH of the galloyl group, whereas sylvatiin D was found to have a chebulinic acid core containing acetylglucose attached in a similar way. The potential of these compounds to act as defensive compounds against herbivores was evaluated using the radial diffusion assay that measures the protein precipitation capacity. In addition, the capacity of sylvatiins to act as co-pigments with anthocyanins of G. sylvaticum petals was measured in vitro at different pH values. Sylvatiins A and D maintained efficiently the purple flower color near the natural pH of petal cells. The amount of sylvatiins was changed according to the flower color; deep purple petals with higher amount of anthocyanin contained more sylvatiins A and C than whiter petals. It was concluded that G. sylvaticum petal cells may accumulate sylvatiins for intermolecular co-pigmentation purposes.

Most land plants grow in association with arbuscular mycorrhizal fungi (AMF) in their roots and these fungi can cause transgenerational effects on plants' offspring. These may be caused by changes in DNA methylation of the offspring. In this study, we compared the amount of global DNA methylation in seeds of the gynodioecious plant Geranium sylvaticum in relation to the gender and the AMF status of the parents producing the seeds. The amount of DNA methylated was positively related to seed mass. Seeds produced by females had a similar proportion of methylated DNA regardless of the AMF status of the father siring the seed. By contrast, seeds from hermaphrodites had higher DNA methylation when sired by AMF fathers. We show to the best of our knowledge for the first time, that the AMF status of fathers can affect DNA methylation in seeds and that these changes in DNA methylation are further dependent on the gender of the mother producing the seeds.

Sex-specific interactions with antagonists may explain female maintenance in gynodioecious populations if seeds produced by hermaphroditic plants are preferred over seeds produced by female plants. Among antagonistic interactions, pre-dispersal seed predators have received relatively little attention even though they may exert sex-specific selective pressures on the evolution of floral and flowering traits. In this work, I investigate temporal variation in seed predation in gynodioecious Geranium sylvaticum, where in addition to female and hermaphrodite individuals, plants with an intermediate sexual expression are also present in most populations. Specifically, I examined whether seed predation is linked to flowering phenology, plant gender, and sexual dimorphism in floral and seed traits over the flowering season using an experimental field population. Within the population, I selected female, intermediate, and hermaphrodite plants with different timing of flowering onset (early, mid, or late), and collected seeds across the fruiting period. Seeds were weighed and examined for seed predator damage. The results show that the three genders experienced similar levels of seed predation attack regardless of their flowering phenology, and that overall seed predation was not related to changes in seed production or seed mass. These results suggest that sexual dimorphism in seed predation cannot be responsible for female maintenance in this species.

Most flowering plants species rely on insects for pollination, a successful mutualism allowing them to reproduce over wide areas while flower-visitors are rewarded with food. This association is so conspicuous in the case of bees that other groups of potential pollinators, especially flies, have long been underestimated. However, visitors are not always pollinators. While the importance of flies in plant–visitor networks is now acknowledged, their pollination effectiveness has hardly been investigated. In this study, we assessed the pollination effectiveness ofGeranium sylvaticumflower-visitors using single-visit seed set experiments, in a subalpine meadow where flies are predominant. We found that: (i) empidine dance flies were the most frequent visitors ofG. sylvaticum; (ii) a single-visit by an empidine dance fly produced the same average number of seeds as a visit by a bee; (iii) large pollinators were more efficient than small pollinators irrespective of their identity. As a conclusion, large empidines were the main pollinators ofG. sylvaticum. Considering the high diversity and abundance of flower-visiting fly species, such results showing their ability to be as effective pollinators as bees should encourage further studies to develop a better understanding on their role in plant–pollinator networks.

A combination of high-resolution mass spectrometry and modern HPLC column technology, assisted by diode array detection, was used for accurate characterization of water-soluble polyphenolic compounds in the pistils, stamens, petals, sepals, stems, leaves, roots and seeds of Geranium sylvaticum. The organs contained a large variety of polyphenols, five types of tannins (ellagitannins, proanthocyanidins, gallotannins, galloyl glucoses and galloyl quinic acids) as well as flavonoids and simple phenolic acids. In all, 59 compounds were identified. Geraniin and other ellagitannins dominated in all the green photosynthetic organs. The other organs seem to produce distinctive polyphenol groups: pistils accumulated gallotannins; petals acetylglucose derivatives of galloylglucoses; stamens kaempferol glycosides, and seeds and roots accumulated proanthocyanidins. The intra-plant distribution of the different polyphenol groups may reflect the different functions and importance of various types of tannins as the defensive chemicals against herbivory.

In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit set, pollen production and floral size. The two AM species used in the present work had different effects on plant fitness parameters. One AM species increased female fitness through increasing seed number and seed mass, while the other species reduced seed mass in all sexes investigated. AM fungi did not affect intermediate and hermaphrodite pollen content in anthers. The three sexes in G. sylvaticum did not differ in their reproductive output in terms of total seed production, but hermaphrodites had potentially larger fathering ability than intermediates due to higher anther number. The ultimate female function--seed production--did not differ among the sexes, but one of the AM fungi used potentially decreased host plant fitness. In addition, in the intermediate sex, mycorrhizal symbiosis functioned similarly in females as in hermaphrodites.

In gynodioecious plants, females are predicted to produce more and/or better offspring than hermaphrodites in order to be maintained in the same population. In the field, the roots of both sexes are usually colonized by arbuscular mycorrhizal (AM) fungi. Transgenerational effects of mycorrhizal symbiosis are largely unknown, although theoretically expected. We examined the maternal and paternal effects of AM fungal symbiosis and host sex on seed production and posterior seedling performance in Geranium sylvaticum, a gynodioe- cious plant. We hand-pollinated cloned females and hermaphrodites in symbiosis with AM fungi or in nonmycorrhizal conditions and measured seed number and mass, and seedling survival and growth in a glasshouse experiment. Females produced more seeds than hermaphrodites, but the seeds did not germinate, survive or grow better. Mycorrhizal plants were larger, but did not produce more seeds than nonmycorrhizal plants. Transgenerational parental effects of AM fungi were verified in seedling performance. This is the first study to show transgenerational mycorrhiza-mediated parental effects in a gynodioecious species. Mycorrhizal symbiosis affects plant fitness mainly through female functions with enduring effects on the next generation.

Habitat loss, fragmentation of meadow patches, and global climate change (GCC) threaten plant communities of montane grasslands. We analyzed the genetic structure of the montane herb Geranium sylvaticum L. on a local scale in order to understand the effects of habitat fragmentation and potential GCC impacts on genetic diversity and differentiation. Amplified fragment length polymorphism (AFLP) fingerprinting and cpDNA sequencing was performed for 295 individuals of 15 G. sylvaticum populations spanning the entire distribution range of the species in the Taunus mountain range in Germany. We found patterns of substantial genetic differentiation among populations using 150 polymorphic AFLP markers (mean F ST = 0.105), but no variation in 896 bp of plastid DNA sequences. While populations in the center of their local distribution range were genetically diverse and less differentiated, higher F ST values and reduced genetic variability was revealed for the populations at the low-altitudinal distribution margins. Projections of GCC effects on the distribution of G. sylvaticum in 2050 showed that GCC will likely lead to the extinction of most edge populations. To maintain regional genetic diversity, conservation efforts should focus on the diverse high-altitude populations, although a potential loss of unique variations in genetically differentiated peripheral populations could lower the overall genetic diversity and potentially the long-term viability in the study region. This study documents the usefulness of fine-scale assessments of genetic population structure in combination with niche modeling to reveal priority regions for the effective long-term conservation of populations and their genetic variation under climate change.

Geranium sylvaticum is a common herbaceous plant in Fennoscandia, which has a unique phenolic composition. Ellagitannins, proanthocyanidins, galloylglucoses, gallotannins, galloyl quinic acids and flavonoids possess variable distribution in its different organs. These phenolic compounds are thought to have an important role in plant-herbivore interactions. The aim of this study was to quantify these different water-soluble phenolic compounds and measure the biological activity of the eight organs of G. sylvaticum. Compounds were characterized and quantified using HPLC-DAD/MS, in addition, total proanthocyanidins were determined by BuOH-HCl assay and total phenolics by the Folin-Ciocalteau method. Two in vitro biological activity measurements were used: the prooxidant activity was measured by the browning assay and antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Organ extracts were fractionated using column chromatography on Sephadex LH-20 and the activities of fractions was similarly measured to evaluate which polyphenol groups contributed the most to the biological activity of each organ. The data on the activity of fractions were examined by multivariate data analysis. The water-soluble extracts of leaves and pistils, which contained over 30% of the dry weight as ellagitannins, showed the highest pro-oxidant activity among the organ extracts. Fraction analysis revealed that flavonoids and galloyl quinic acids also exhibited high pro-oxidant activity. In contrast, the most antioxidant active organ extracts were those of the main roots and hairy roots that contained high amounts of proanthocyanidins in addition to ellagitannins. Analysis of the fractions showed that especially ellagitannins and galloyl quinic acids have high antioxidant activity. We conclude that G. sylvaticum allocates a significant amount of tannins in those plant parts that are important to the fitness of the plant and susceptible to natural enemies, i.e. pistil and leaf tannins protect against insect herbivores and root tannins against soil pathogens.

Amongst gynodioecious plant breeding systems, there can exist intermediate morphs with a reduction in their male function (i.e. reduced number of functional anthers). Along with this sexual trimorphism, plants can also show floral colour polymorphism. Such intricate mixtures of phenotypes within a species may have complex effects on floral rewards. Floral rewards are known to vary between sexually dimorphic species and to a lesser extent between colour morphs. However, the interactive effect of sexual trimorphism and colour polymorphism is unexplored. We measured nectar’s sugar content in the sexually trimorphic Geranium sylvaticum, a gynodioecious plant with a light/dark floral polymorphism. We found that nectar reward differed across genders and colour morphs. Results were not however consistent within the three genders; dark female and hermaphrodite flowers had higher sugar content than light morphs, whereas intermediate flowers did not. As expected, females and hermaphrodites had different nectar reward, with intermediate morphs being midway between the other genders. In intermediates, the sugar content was not related to the number of functional stamens. We show for the first time the existence of sex-specific differences between flower gender and colour morphs in nectar rewards. Our results demonstrate the importance of considering multiple and conflicting selection pressures to explain rewards.

PREMISE OF THE STUDY: Sex lability (i.e., gender diphasy) in plants is classically linked to the larger resource needs associated with the female sexual function (i.e., seed production) compared to the male function (i.e., pollen production). Sex lability in response to the environment is extensively documented in dioecious species, but has been largely overlooked in gynodioecious plants. METHODS: Here, we tested whether environmental conditions induce sex lability in the gynodioecious Geranium sylvaticum. We conducted a transplantation experiment in the field where plants with different sex expression were reciprocally transplanted between high light and low light habitats. We measured plants’ reproductive output and sex expression over four years. KEY RESULTS: Our results show that sex expression was labile over the study period. The light level at the destination habitat had a significant effect on sexual expression and reproductive output, because plants decreased their reproductive output when transplanted to the low light habitat. Transplantation origin did not affect any parameter measured. CONCLUSIONS: This study shows that sex expression in Geranium sylvaticum is labile and related to light availability. Sexually labile plants did not produce more seeds or pollen, and thus, there was no apparent fitness gain in sexually labile individuals. Sex lability in gynodioecious plants may be more common than previously believed because detection of sex lability necessitates data on the same individuals over time, which is rare in sexually dimorphic herbaceous plants.

An improved understanding of population-level consequences of grazing on plants can be facilitated by an assessment of grazing effects on all stages in the life-cycle. In this study, 6 years of demographic data for three populations of the perennial herb Geranium sylvaticum were analysed. We examined the effects of sheep grazing (high sheep density, low sheep density and no sheep) and interannual climatic variability on vital rates and population growth rates (λ). Grazing did not affect survival or flowering rates, but reduced rates of growth and increased rates of clonal reproduction. At the population level, high contributions from retrogression and clonal reproduction buffered reduced rates of growth and stasis, and no consistent differences in λ between populations exposed to different sheep densities were found. Instead, large between-year variability in λ, independent of sheep density, was detected, related to variation in the local summer climate. The results indicated, however, that grazing effects on λ were more severe in unfavourable than in normal years. Our study highlights that increased clonal reproduction rates functioned as a tolerance mechanism towards grazing in this herb, which forms a mechanism to explain how moderate population responses to grazing in some herbs can arise.

Both plant sex and arbuscular mycorrhizal (AM) symbiosis influence resource acquisition and allocation in plants, but the interaction between these two components is not well established. As the different plant sexes differ in their resource needs and allocation patterns, it is logical to presume that they might differ in their relationship with AM as well. We investigate whether the association with AM symbiosis is different according to the host plant sex in the gynodioecious Geranium sylvaticum, of which, besides female and hermaphrodite plants, intermediate plants are also recognized. Specifically, we examine the effects of two different AM fungi in plant mass allocation and phosphorus acquisition using a factorial greenhouse/common garden experiment. Cloned G. sylvaticum material was grown in symbiosis with AM fungi or in non-mycorrhizal condition. We evaluated both the symbiotic plant benefit in terms of plant mass and plant P content and the fungal benefit in terms of AM colonization intensity in the plant roots and spore production. Our results suggest that G. sylvaticum plants benefit from the symbiosis with both AM fungal species tested but that the benefits gained from the symbiosis depend on the sex of the plant and on the trait investigated. Hermaphrodites suffered most from the lack of AM symbiosis as the proportion of flowering plants was dramatically reduced by the absence of AM fungi. However, females and intermediates benefited from the symbiosis relatively more than hermaphrodites in terms of higher P acquisition. The two AM fungal species differed in the amount of resources accumulated, and the fungal benefit was also dependent on the sex of the host plant. This study provides the first evidence of sex-specific benefits from mycorrhizal symbiosis in a gynodioecious plant species.

1. Arbuscular mycorrhizal (AM) symbiosis has been shown to enhance some plant traits to which pollinators are known to respond. Moreover, in gynodioecious species pollinators prefer hermaphrodite flowers over female ones, but the role of fungal symbiosis in sex-specific pollinator attraction is unknown. 2. We examined how plant gender dimorphism and AM symbiosis affect floral visitors and reproductive output in the gynodioecious plant Geranium sylvaticum. Floral visitors were moni- tored in a common garden experiment using mycorrhizal plants inoculated with either Glomus claroideum or Glomus hoi and in non-mycorrhizal condition. 3. We hypothesized that because of the larger flower display and pollen presence in hermaph- rodites, (i) hermaphrodites receive more floral visitors than females. However, as females pro- duce higher numbers of seeds than hermaphrodites, we predicted that (ii) effective pollinators visit both sexes equally and that (iii) AM symbiosis, although affecting floral characteristics and insect behaviour in general, should not have sex-specific effects on insects that transport pollen. 4. Our results confirm the hypotheses as hermaphrodites received 1AE5 times as many floral visi- tors than females. However, the most important pollinator group, the bumblebees, did not prefer either sex, which may be important for the maintenance of both sexes in gynodioecious popula- tions. We further corroborated that AM symbiosis, although affecting flower size and the amount of pollen, did not affect bumblebee behaviour, whereas other hymenopterans showed a deterrence for G. hoi inoculated plants. 5. This work reports the impact of AM symbiosis on the behaviour of floral visitors in a sexually dimorphic plant species. Positive interactions between plants, floral visitors and AM have been documented previously. However, potential negative tritrophic interactions between plants, floral visitors and AM may also occur. Our results suggest that plant sex and the mycorrhizal status of the plant also influence floral visitor groups that are unlikely to carry out pollination. This may benefit the plants if these floral visitors carry fungal diseases and consume pollen and nectar without effectively vectoring pollen.

A find of Pirottaea from dead stems of Silene dioica collected in the Bohemian Switzerland National Park is described. The material possesses very well developed setae, is assigned to Nannfeldt’s evolutionary lineage 2, and within the lineage differs from Pirottaea pilosissima known from stems of Geranium sylvaticum by shorter and up to 4-septate setae. Peziza sphaerioides var. lychnidis was revised and found to be conspecific with our material, but invalid. The earliest valid description of the taxon was found and a new combination is proposed. Results of a revision of several specimens of Pirottaea spp. published from the area of the Czech Republic are given.

Several factors have been proposed to explain female maintenance in gynodioecious populations. In this study, we propose and test a novel hypothesis: greater tolerance to herbivory through more beneficial interactions with plant fungal mutualists might also help to explain female maintenance. Herbivory limits the amount of carbon and nutrients available for the plants and has been shown to affect mycorrhizal colonization. We hypothesized that simulated herbivory would decrease reproductive output, mycorrhizal colonization intensity, and the phosphorus content relatively more in hermaphrodites, so females would achieve higher advantage over hermaphrodites when under herbivory pressure. We tested it in the field using the gynodioecious plant Geranium sylvaticum. We found that simulated herbivory had a negative effect on the reproductive output in both sexes and that there was a similar reduction in fruit set, seed set, and total seed number in both sexes. Defoliation did not affect any fungal parameter measured, but decreased phosphorus content relatively more in females. The plants had a sex-specific relationship with mycorrhizae, but this was not related to herbivory. Thus, we conclude that females do not gain any specific advantage under defoliation from its symbionts at short-term even though it seems that the plants have sex-specific relationship with their mycorrhizal symbionts.

In this study, 119 meadows distributed across the Yorkshire Dales National Park were re-surveyed and changes in the overall vegetation and the landscape structure over the last two decades were investigated with a particular emphasis on the influence of management practices. To study the effects of fragmentation on a particular species, this study focused on changes in the occurrence of the perennial herb Geranium sylvaticum as this is accepted as an indicator of the good ecological condition of British upland hay meadows. Results indicated that there has been a general impoverishment in the vegetation with a decrease in diversity, species richness and habitat quality and meadows have become 10 times more isolated than 20 years ago. Habitat quality was positively associated with agri-environment schemes that encourage extensive management practices, low grazing intensity and organic fertiliser application. G. sylvaticum has disappeared from 40% of the fields where it used to be and its occurrence was influenced by habitat quality and the connectivity of the fields in 2003. For perennial plants that do not have specialised reproduction and dispersal mechanisms like G. sylvaticum , changes at the local scale may have stronger effects on survival than changes at the wider landscape scale. It is thus of utmost importance to maintain and encourage traditional management practices in remaining hay meadows, especially hay making practices that would facilitate the exchange of seeds between fields and improve landscape connectivity.

Flowers of Geranium sylvaticum L. are normally hermaphroditic and have 10 stamens. Some flowers have reduced non-functional anthers or do not have anthers at all; these flowers are called female flowers. Flowers with 1–9 functional anthers are classified as intermediate (Asikainen & Mutikainen 2003). Such a reduction probably prevents self-fertilization and lets female flowers produce more seeds, or seeds with greater nutrient stores, which increases the population’s fitness (Asikainen & Mutikainen 2003, 2005; Ramula & Mutikainen 2003). A negative correlation has been found between the frequency of female flowers and seed production of hermaphroditic flowers in G. sylvaticum populations (Asikainen M female flowers are less frequent in southern populations (Asikainen & Mutikainen 2003). Low numbers of ‘intermediate’ flowers were found in very low frequency (less then 1%) in less than half of the Southern Finland populations, and only one population had 42% of intermediate-type flowers. Northern populations, in contrast, showed higher frequencies of intermediate flowers. Sex ratio variation among populations may also be explained by ecological factors that affect the relative seed fitness of the two gender morphs (Asikainen & Mutikainen 2003). As G. sylvaticum is widely distributed in Europe and Asia, we decided to investigate other populations of this species to determine whether the latitudinal distribution pattern of flower type observed in Finland is a general pattern. We also attempted to check whether sex ratio variation between populations is caused by habitat conditions.

Background and Aims For the maintenance of gynodioecy (i.e. the coexistence of female and hermaphroditic plants), females need to compensate for the lack of pollen production through higher seed production or better progeny quality compared to hermaphrodites. In Geranium sylvaticum, females produce more seeds per flower than hermaphrodites. This difference in seed production might be modified by biological interactions with pollinators and herbivores that may favour one sex and thus affect the maintenance of gynodioecy. Methods Sexual dimorphism in flower size and flowering phenology, and in attractiveness to pollinators, pre-dispersal seed predators and floral herbivores were examined in natural populations of G. sylvaticum. Key Results Pollinators preferred hermaphrodites 25 % more often than females in two of the three study populations, and floral herbivores attacked hermaphrodites 15 % more often than females in two of the six study populations. These preferences might be explained by the larger flower size of hermaphrodites. In contrast, seed predators did not prefer either sex. Conclusions The data suggest that pollinator preference does not benefit females, whereas the higher floral herbivory of hermaphrodites might enhance the maintenance of females in G. sylvaticum. Thus, although the data support the view that ecological factors may contribute to the maintenance of gynodioecy, they also suggest that these contributions may vary across populations and that they may function in opposite directions.