Plant Biology

Keel flowers are bilaterally symmetrical, pentamerous flowers with the reproductive organs enclosed by keel petals. Within Fabales, keel flowers are dominant in two species-rich lineages, tribe Polygaleae (Polygalaceae) and subfamily Fabaceae (Papilionoideae); however, independent events are also observed, such as in the genus Cercis. Before phylogenetic advancements were available (i.e., in contrast to more recent studies), most of the studies hypothesized a non-keeled origin for the Faboideae, although a detailed investigation has never been carried out. In this study, using the results of Aygoren Uluer et al. (2020, 2022a), the origin of some important morphological characters of the keel flower are examined, namely floral symmetry, perianth heteromorphism (i.e., three distinct petal/+sepal types), and the presence of enclosed reproductive organs. These characters are analysed within the Fabales using three different ancestral state analyses based on a phylogeny constructed for 678 taxa using published matK, rbcL and trnL plastid gene regions. The analyses show that symmetry probably originated in the (Fabaceae+Polygalaceae) clade, while the enclosed reproductive organs and three-types of petals appear to have evolved independently multiple times. Interestingly, not only the enclosed reproductive organs but also petal heteromorphism probably did not evolve in the MRCA of the Faboideae, but rather in a very early stage of the evolution of the subfamily. While future homology assessments and/or evolutionary developmental genetic (evo-devo) studies will be required to more clearly elucidate the evolutionary processes, the current study is the first attempt to investigate the origin of some important characteristics of keel flowers within order Fabales.

A Gabonese taxon cultivated for decades in the botanic gardens of Europe as Anchomanes nigritianus is shown to be a new species to science, and on current evidence, is best placed as the fourth species of the Gabonese-centred, poorly known genus Pseudohydrosme. Data on the morphological separation between Anchomanes and Pseudohydrosme are reviewed. Although phylogenomic studies may show in future that the two genera need to be merged, for the moment their separation is reinforced on morphological grounds. Anchomanes lacks the spathe tube, ovoid-globose, 2 - 4 locular pistil and thick, lobed stigma on a symmetric, stout style that we show to characterise the redelimited Pseudohydrosme. (Anchomanes has oblong, polygonal, 1-locular pistils, stigmas asymmetric, sessile, thin and disc-like or on asymmetrical conical styles and are pointed or brush-like). In addition, Pseudohydrosme (where known) has stipitate (versus sessile) fruits and on current evidence lacks the lacticifers recorded from Anchomanes. We test the hypothesis that the taxon is a new species to science, naming it as Pseudohydrosme bogneri, and conclude that it is Critically Endangered (Possibly Extinct) using the IUCN 2012 standard. Pseudohydrosme bogneri appears to be the tenth documented probable global extinction of a plant species that has occurred among the narrowly endemic plant species of the Libreville area, Gabon.

Flower scents are crucial for attracting pollinators to Annonaceae flowers. Pollinators are likely drawn exclusively to female flowers. Since pollinators remain inside the pollination chamber throughout anthesis in several species, it is believed that the aroma during the male phase does not attract pollinators and may even repel them. However, few studies have characterised the scents of Annonaceae species flowers during both the male and female phases, so this hypothesis has not been comprehensively evaluated. Here we characterise the reproductive ecology of Annona macroprophyllata, including individual- and flower-level phenology, mutualistic and non-pollinating interactions, and floral scent emissions. Our results showed that Annona macroprophyllata has receptive flowers at night, with the entire extent of reproductive activity restricted to an 8 hours-period. Female and male flowers are synchronous with differences in the proportion of flowers depending on the nighttime. Low diversity and abundance of floral visitors were observed. Four guilds were distinguished as pollinators, florivores, insect predators and random or non-specific visitors. Pollinators were insects (Nitulidae) that entered the pollination chamber during the female phase and remained inside the flower throughout anthesis. The comparison of floral scent diversity among flower phases showed that scent composition differs between the phases of A. macroprophyllata flowers. The scent of the female flower mimics the sweet smell of fruit, which usually attracts Nitulid beetles. In contrast, the fermented odors of the male phase seem to repel them, contributing to their release or ensuring that they visit only female flowers. This study reveals an attraction-repulsion pollinator system in Annona macroprophyllata, which could be a common floral attribute within the Annonaceae family.

Interspecific hybridisation and polyploidization are two main driving forces in plant evolution, shaping genomes and favouring evolutionary novelty and ecological adaptation. Recent studies have demonstrated hybridisation within the genus Lemna (Lemnaceae Martinov) as well as triploid. L. x mediterranea, a recently described hybrids between Lemna minor and Lemna gibba was identified among only long lasting germplasm collections of in vitro propagated plants, originally collected at different times in the Mediterranean area. We report the first distribution record of L. x mediterranea in the nature, in the Campania region of Southern Italy, the same area where Lemna symmeter was described as a new species about 50 years ago, confirming their synonymy. Eight specimens isolated from five different sampling sites over an area of about 4200 Km2 showed identical genetic profiles by Tubulin-Based Polymorphism (TBP) analysis, suggesting their common origin from the same hybridisation event, followed by clonal dispersal. The L. x mediterranea population of Campania is genetically different from any of the previously analysed clones, suggesting that recurrent hybridisation between the parental species may occur. The natural hybrid clone is triploid, with L. gibba as the plastid donor, and remarkably similar to it by morphology, although the typical gibbosity of this species becomes evident only upon in vitro flower induction. Flowers are protogynous and self-sterile. Ecological factors including competition with parental and invasive species, niche and climate change adaptation, stability in time and space likely played a role in the successful establishment of L. x mediterranea. HighlightsO_LIInterspecific hybridisation within the genus Lemna documented in nature C_LIO_LI{beta}-tubulin intron length polymorphism for tracking duckweed species distribution C_LIO_LIFlower induction in Lemna x mediterranea C_LI

In Sicily, H. helix is the unique known native species whereas H. helix susbsp. poetarum is putatively naturalized in some forests and H. canariensis cultivated in various urbans garden. Trichome morphology and genome size of some ivies from various west Mediterranean forests were compared to Sicilian ones. Ivies from southern Italy, continental France, Corsica and Mallorca belong to typical European diploid stellate trichomes Hedera helix. Hexaploid ivies from southern Spain have been identified as native H. iberica. Contrariwise, Sicilian ivies studied are related to western European H. hibernica (tetraploids with stellate trichomes). Is H. helix the most widespread and indigenous ivy in Sicily? Therefore, it would be the first time that tetraploid would be reported in Sicily where it could possibly correspond to an unnoticed autochthonous taxon. However, our results let us think it rather represents an invasive which impact on this island rich in endemic species could be considerable.

Saxicolella Engl., an African genus of the waterfall specialist plant family Podostemaceae, was shown to be polyphyletic as currently delimited. One clade, sampled from species in Ghana, is sister to American Ceratolacis (Tul.)Wedd., Podostemum Michx. and all Old World Podostemoideae (podostemoids). The second clade, sampled from Cameroonian material, was embedded within the major clade of African podostemoids. In this paper the generic nomenclature applied to Saxicolella sensu lato (Saxicolella, Pohliella Engl., Aulea Lebrun & Stork nom. inval.), is reviewed and the morphological support for the two clades and their correct generic names is determined. Pohliella is shown to be the correct name for the first clade (based on Pohliella laciniata Engl., Cameroon) and a synoptic treatment of its three published species is given, one of which is extinct, and two are threatened. However, a fourth, unpublished species exists. The new combinations Pohliella submersa (J.B.Hall) Cheek and Pohliella amicorum (J.B. Hall) Cheek are made for the two published Ghanaian species. The recently described New World genus Cipoia C.T. Philbrick, Novelo & Irgang is revealed as being morphologically identical to Pohliella, but in view of the geographical disjunction, confirmation from molecular evidence is awaited before its two species are also transferred to Pohliella. The correct name for the second clade, embedded in African podostemoids, is Saxicolella (sensu stricto), now with two known species, Saxicolella nana Engl. (type of Saxicolella, Cameroon) and Saxicolella flabellata (G.Taylor) C. Cusset (Nigeria).

In Europe, the genus Tolypella (Characeae) comprises four to eight Tolypella species in sections Rothia and Tolypella that have been distinguished by vegetative morphology and gametangial characters such as antheridial size and oospore cell wall ornamentation. However, morphological species differentiation is difficult in some cases due to overlapping and variable vegetative features, which in many cases are difficult to observe clearly. To clarify the taxonomic status of the five European species of Tolypella in section Tolypella, sequence data of the plastid genes atpB, rbcL and psbC for Tolypella glomerata (Desv.) Leonh., Tolypella hispanica Allen, Tolypella nidifica (O.F. Mull.) A. Braun, Tolypella normaniana (Nordst.) Nordst. and Tolypella salina Cor. were combined with data on oospore morphology, including oospore wall ornamentation. Gene sequence data identified five distinct clusters, but they differed from the morphologically identified five species. T. glomerata consisted of some of the samples morphologically identified as T. glomerata and seven samples of T. normaniana, while the remaining T. glomerata samples clustered with specimens of unclear affiliation ("Tolypella. sp."). T. hispanica I consisted of samples from various locations, whereas "T. hispanica II" consisted of samples of T. hispanica from the Mediterranean island, Sardinia. The remaining cluster consisted of all the specimens that had been determined as T. salina or T. nidifica in addition to two specimens of T. normaniana. Oospore morphology was most clearly distinguishable for T. glomerata. Oospore characteristics for all other taxa were not as informative but showed some geographical and/or environmentally influenced differences, especially for T. nidifica and T. salina. Our results suggest a significantly different taxonomy of Tolypella sect. Tolypella in which specimens normally identified as T. glomerata might be two different species, T. glomerata and an unidentified species; T. nidifica and T. salina are not separate species; T. normaniana is a diminutive variant of T. nidifica or T. salina; and T. hispanica comprises two different species, one from the Mediterranean island Sardnia.

PremiseThe family Annonaceae possesses a broad array of floral phenotypes and pollination specialisations, and are important in the plant-pollinator interactions of tropical rainforests. Although there has been considerable effort to assess their interactions with pollinators, attempts to characterise their visual and olfactory communication channels are scarce. MethodsHere, we investigated the pollination biology of 12 Annonaceae species from five genera, viz. Meiogyne, Monoon, Polyalthia, Pseuduvaria, and Uvaria. Furthermore, their floral colour was characterised by reflectance spectroscopy and floral odour chemistry was assessed using gas chromatography-mass spectrometry. Floral scent was further compared across the whole family using non-metric dimensional scaling plots to identify specialisation in floral odour. ResultsThe Meiogyne species are likely pollinated by small beetles; the Polyalthia and Pseuduvaria species are likely pollinated by beetles and flies; and the Uvaria species is likely pollinated by beetles and bees. Flowers of most species are UV non-reflective, and have various spectral reflectance profile across the remaining visible spectra. Multiple species produce floral odour resembling ripe fruits. The flowers of Meiogyne species and Polyalthia xanthocarpa emitted mostly branched-chain esters, while flowers of Uvaria released mainly straight-chain esters. The Pseuduvaria species instead emitted scent reminiscent of rotten fruits, largely consisting of 2,3-butanediol. The inner petal corrugation in Meiogyne functions as a food reward, and the inner petal growth serves as a nectary gland for Pseuduvaria. ConclusionsOur study identifies the visual and olfactory cues of multiple Annonaceae species and provides insights into how Annonaceae flowers attract different guilds of pollinators.

Floral mimicry is a captivating phenomenon wherein flowers imitate traits of other species to attract specific pollinators. The Caesalpinioideae legumes in general have relatively unspecialized flowers, which has allowed the development of disparate morphologies associated with adaptation to different types of pollinators. This study describes the pollination of Moldenhawera nutans and explores its potential floral mimicry towards Malpighiaceae flowers. Our investigation revealed that M. nutans is pollinated by species of Centris Fabricius, 1804 and Xylocopa Latreille, 1802. It also presents compelling evidence supporting the hypothesis of floral mimicry, including striking similarities in floral display, shared oil-collecting pollinators, oil collection behavior in M. nutans despite the absence of oil production, and the reliance on exogenous pollen for reproduction. These findings suggest that species of Centris bees visit M. nutans flowers under the mistaken impression of oil availability, subsequently transitioning to pollen collection. We explored other potential cases of floral mimicry with Malpighiaceae in the Caesalpinioideae legumes by optimizing the Malpighiaceae-like floral display on a dated phylogeny of this subfamily. However, current information does not allow us to determine whether the similarities in floral morphology represent cases of floral mimicry, phylogenetic inertia, or simple convergence. Several hypothesis tests are suggested that can guide the study of these fascinating evolutionary processes in the group.

Background and aimsFloral color polymorphism is common in angiosperms, yet in perennial, clonal plants, proximate trait differences and reproductive differences among sympatric morphs remain poorly understood. This is primarily because perennial individuals can carry signatures of past selection regimes. We studied bract color polymorphism in a nocturnal ginger Curcuma caulina to ask: (i) Do nectar rewards, reproductive compatibility and pollinator visitation differ among color morphs? (ii) Does morph abundance correlate with fitness via ecological (pollinator-mediated) or physiological (compatibility) pathways? (iii) Do these traits predict realized reproductive success? MethodsWe measured 22 floral/vegetative traits (n=30 per morph), nectar rewards (106 flowers), pollinator visitation rates (648 hours), and physiological compatibility (471 hand-pollinations treatments) and natural fruit and seed set ([≥]50 per morph) across three dominant morphs. Path analysis tested direct and indirect effects of morph abundance, nectar traits, pollinator visitation, and compatibility on reproductive fitness. Key resultsMorphs did not differ in their morphological traits but showed differential nectar and reproductive compatibility traits. The rare red-white morph produced the highest nectar energy, received the most visits, had a leaky self-compatibility, and yet showed lowest seed count per fruit, while the most common green-red morph was self-incompatible, showed higher cross-compatibility and had highest seeds per fruit. The second common green-white morph showed intermediate abundance and also showed leaky self-compatibility. Path analysis indicated that morph abundance had both direct and indirect effects on reproductive fitness, mediated by nectar, pollinator visitation and compatibility. ConclusionsReproductive success of the polymorphic C. caulina is a result of multi-trait interactions including pollinator interaction. That is, nectar traits and mating-system differences shape reproductive fitness of the morphs. We also highlight that in polymorphic perennial plants contemporary selection regimes may be acting alongside genotypic vestiges (historical genotypes present in extant population), thus complicating any frequency-dependent selection regime.

We definitively place Keraunea, a genus of showy forest climbers from remnants of the Mata Atlantica of Brazil, in Ehretiaceae. Previously Keraunea had been ascribed to Convolvulaceae based on morphology, or divided between Malpighiaceae and Ehretiaceae based on molecular analyses (polyphyletic). Keraunea is morphologically anomalous in the Ehretiaceae, having fruits which are held in the centre of a large wing-like bract by adnation of the pedicel, and due the stem-twining habit of some species. However, morphologically Keraunea shares two apomorphies with monotypic Cortesia Cav., halophytic shrubs of Argentina: 1) "two parted endocarps" (the fruit contains two endocarps each with two 1-seeded cells, while four 1-seeded endocarps are plesiomorphic in Ehretiaceae) and 2) a large bract that subtends the flower (absence of bracts is plesiomorphic in Ehretiaceae). A combined tree using four markers (ITS, trnL-F, rbcL and matK) places the three species of Keraunea sampled unambiguously in a clade with Ehretia + Cortesia + Halgania and monophyly for Keraunea is shown with high support. In an ITS tree Keraunea is sister to Cortesia with low support. We expand the generic description of Keraunea including the first account of the internal fruit structures and the seed, and present new data on the vegetative architecture including variation within the genus, some species being stem twiners while one species at least, is described as a scandent shrub. Keraunea lombardiana, previously included within K. brasiliensis, is formally described from Minas Gerais and Bahia as the third species of the genus and both these species are described. In all five species are recognised but two, known to us only from digital images, are not formally described because sufficiently detailed descriptions cannot be made. All five species are mapped, and provisional conservation assessments are recorded, of either Endangered or Critically Endangered. The state of Bahia, with three species, has the highest species diversity, mainly in dry forest. Three species appear confined to moist coastal forest, extending southwards from Bahia to the state of Rio de Janeiro. Keraunea remains incompletely known. Not one of the species has both anthetic flowers and fruits described. Studies on pollen, germination, anatomy, embryology and phytochemisty are entirely lacking. Field observations of pollination, seed dispersal and phenology are also required. However, the most urgent requirement is undoubtedly a formal taxonomic revision based on a full herbarium search and targeted fieldwork, with full IUCN 2012 extinction risk assessments for each taxon. This is urgent because it seems that all the taxa that we present in this paper (and more that can be expected to be found) appear to be highly range restricted and generally not to occur in protected areas, and so appear to be highly threatened.

The growing global horticultural trade is having a steadily increasing impact on the rate at which alien species are introduced into new areas, partly because horticultural trade also entails the unintentional dispersal of many contaminant species. Although there are reports about noteworthy occurrences of alien plant species in garden centres, this phenomenon has hardly been studied systematically. To bridge this knowledge gap, we conducted systematic field surveys in 12 garden centres in Hungary to assess their alien flora. We hypothesised that (i) the number of alien species inhabiting a garden centre is positively correlated with its size, (ii) relative to their size, garden centres host a disproportionately large proportion of the local alien flora, and (iii) alien species inhabiting garden centres differ from the regional alien flora in their traits. We recorded altogether 93,788 individuals of 67 introduced species, seven of which have not yet been reported from the country. There was considerable variability in the number of species and individuals found in each garden centre, but there was no correlation between the size of the garden centres and the number of species they host. Despite their relatively small size, the studied garden centres hosted a considerable proportion of the local alien flora, indicating that they strongly accumulate alien species and that they can act as invasion hubs for several alien species. Alien species inhabiting garden centres differed from the regional alien flora in some of their trait values, indicating that the species that are most successful at establishing populations inside garden centres are both good dispersers and possess an effective resource-acquisitive strategy. We conclude that established alien plant populations in garden centres may induce local invasions, and in the meantime, individuals and seeds inside the containers of ornamental plants are regularly transported to distant areas by the customers. Therefore, plant species dispersed as contaminants of horticultural stock need to be better considered in invasion biology to reduce the threat they may present.

Pellaea ovata is a widespread species, sexual diploid in Texas &northeastern Mexico but an apogamous triploid in northwestern Mexico, south to northern Argentina, &on Hispaniola. The type belongs to the southern, apogamous triploid form. Although these two forms have been discussed repeatedly in the literature, morphological distinctions between them have been overlooked and they have not been recognized taxonomically. However, they are distinct. Pellaea ovata s.s. has puberulent rachides & costae; pinnae usually 2-pinnate with a well-defined main axis &pinnules borne singly; fertile pinnules ovate, cordate basally &rounded apically. The sexual diploid form has rachides &costae glabrous; pinnae pseudo-dichotomously branched &pinnules usually paired; fertile pinnules narrowly rounded-trapeziform, obliquely truncate to cordate basally &truncate apically. Riddell named the sexual diploid form Pteris zygophylla, from which I give it the new combination Pellaea zygophylla.

Two new species of cloudforest tree are described and illustrated from the Cross-Sanaga Interval within the Lower Guinea Domain. Sericanthe etugei Cheek from South West and Littoral Regions of Cameroon is species from the Cameroon Highlands, and Sericanthe onanae Cheek from South West Region, Cameroon, and Bioko (Equatorial Guinea). Sericanthe etugei is similar to Sericanthe leonardii (N. Halle) Robbr. of DRC (Kivu) and Rwanda, differing in the stipular awn 0.25 mm long (vs 1 - 4 mm), the adaxial leaf midrib and secondary nerves glabrous (vs hairy), the tertiary nerves conspicuously scalariform with the naked eye (vs not visible). The species is also similar to Sericanthe testui var. testui, differing in being a tree (vs liana), with stems not decorticating (vs decorticating), the calyx truncate in bud (vs closed) and in the pubescent ovary (vs glabrous). Sericanthe onanae is similar to S. mpassa Sonke & Robbr. of lowland forest in Gabon, differing from that species in that the leaves have an acumen (0.5 - )0.7 - 0.8(- 1.2) cm long vs 0.3 - 0.5 cm, secondary nerves are 7 - 10 (- 12) on each side of the midrib (vs 4 - 6 in S. mpassa), and that the stipules are 5 - 6.5( - 7) x 3 - 5(- 6) mm ( vs 2.5 mm long) and truncate (vs overtopped by an awn c. 1 mm long). It is also similar to S. jacfelicis (N. Halle) Robbr., differing in that the leaves are smaller (<15 cm long vs 16 - 20 cm long), the abaxial surface of the leaf blade has 7 - 10( -12) lateral nerves on each side of the midrib (vs 5 -7) and has a glossy surface and papery texture (vs matt, coriaceous), the petioles are hairy (vs glabrous), the stipules are 5 - 6.5( - 7) mm long, truncate, lacking an awn or arista, (vs 3 -4 mm long, with an arista 0.5 - 1 mm long). These two new species are both provisionally assessed as Endangered EN B2ab(iii) with the 2012 IUCN standard. The new species are briefly discussed in the context of other newly discovered submontane species from the Cross-Sanaga Interval. We speculate that the seeds of these species may be primate-dispersed.

O_LIThe evolution of mating systems in plants is central for understanding the rise of their diversity on Earth. The transition towards self-fertilization is a well-known example of convergent evolution although the opposite direction is expected to be forbidden according to evolutionary theories. We suggest that the ploidy level could promote changes in the reproductive strategies through its effect on traits related to pollination. C_LIO_LIWe performed controlled crosses on several populations from the polyploid Erysimum incanum species complex, described as predominantly selfing, to evaluate the inbreeding depression. Additionally, we measured mating traits such as floral size, herkogamy, anther exertion, the relative investment in male and female components (P:O ratio) and genetic diversity. C_LIO_LIWe described three ploidy levels in the complex - hexaploids were unknown until now. We found significant differences in the self-pollination success among ploidies and even among populations within the same ploidy. Inbreeding depression was present in higher ploidies, accompanied by bigger flowers with higher anther exposure, increased herkogamy and P:O and genetic diversity. C_LIO_LIThese findings suggest that ploidy could be promoting alternative reproductive strategies to selfing, driving mating system diversification within a selfing species, which has not been previously described in the wild. C_LI

A new genus, Lukea Gosline & Cheek (Annonaceae), is erected for two new species to science, Lukea quentinii Cheek & Gosline from Kaya Ribe, S.E. Kenya, and Lukea triciae Cheek & Gosline from the Udzungwa Mts, Tanzania. Lukea is characterised by a flattened circular bowl-shaped receptacle-calyx with a corolla of three petals that give the buds and flowers a unique appearance in African Annonaceae. Both species are extremely rare shrubs of small surviving areas of lowland evergreen forest under threat of habitat degradation and destruction and are provisionally assessed as Critically Endangered and Endangered respectively using the IUCN 2012 standard. Both species are illustrated and mapped. Material of the two species had formerly been considered to be possibly Uvariopsis Engl. & Diels, and the genus Lukea is placed in the Uvariopsis clade of the Monodoreae (consisting of the African genera Uvariodendron (Engl. & Diels) R.E.Fries, Uvariopsis, Mischogyne Exell, Dennettia Bak.f., and Monocyclanthus Keay). The clade is characterised by often conspicuous, finely reticulate quaternary nervation and incomplete or absent connective shields (in Annonaceae the connective shield is usually complete). Morphologically Lukea is distinct for its broad, turbinate, fleshy pedicel, a synapomorphy. It appears closest to the West African monotypic Monocyclanthus, sharing a trait unusual in the Annonaceae: the calyx in both genera forms a shallow bowl (calyx lobes are absent or vestigial), barely enclosing the base of the petals at anthesis, and persisting as a living, leathery disc at least until the fruit is mature. The placement of Lukea within the Uvariopsis clade is discussed.

Interspecific competition can strongly influence community structure and shape niche breadth and overlap. One of the main factors that determine the hummingbird community structure is competition for food. Hummingbirds functional attributes, such as beak length and body mass, influence nectar acquisition in the flowers, shaping foraging niches according to hummingbird dominance and foraging strategy. This study evaluates how the hummingbirds functional and behavioral attributes are related to plants assemblage in rocky outcrops habitats. We tested the following hypothesis: H1) Functional traits (beak length and body mass) are related to the richness and frequency of pollen grain morphotypes carried by hummingbirds; H2) Dominant and territorial hummingbirds carry a lower richness and frequency of pollen types when compared to subordinate hummingbirds, and H3) Hummingbird species carry different types of pollen grains. We conducted the study between September 2018 and March 2019 in a Campo Rupestre (rocky outcrops) in Southeastern Brazil. Hummingbirds were captured with a trap built based on trapdoors. We recorded their beak size and body masses, marked with commercial bird rings and ink on parts of the body, and then released. Behavioral responses to artificial feeders were collected regarding each visits time and duration and the outcome of aggressive interactions. The pollen adhered to the body parts was collected and identified in the laboratory. Our results showed that neither body size nor aggressive behaviors influenced pollen richness and frequency in rocky outcrops. Beak length was the most important hummingbirds attribute that influenced pollen richness, but not pollen frequency. Short-billed hummingbirds carried the greatest richness of pollen grains. Pollen grain richness and frequency were not related to hummingbird body mass or aggressive behavior. The hummingbird-pollen grain interaction network has shown to be generalized in the pollen grain transport. We conclude that hummingbirds beak length is the central morphological variable to measure pollen grain transport. It has direct implications for the pollination of different plant species.

O_LIPlants can adapt to changing environments by adjusting the production and maintenance of diverse sets of bioactive secondary metabolites. To date, the impact of past climatic conditions relative to other factors such as soil abiotic factors and herbivore pressure on the evolution of plant secondary metabolites is poorly understood, especially for plant roots. C_LIO_LIWe explored associations between root latex secondary metabolites in 63 Taraxacum officinale populations across Switzerland and past climatic conditions, soil abiotic parameters, and root herbivore pressure. To assess the contribution of environmental effects, root secondary metabolites were measured in F0 plants in nature and F2 plants under controlled greenhouse conditions. C_LIO_LIConcentrations of root latex secondary metabolites were most strongly associated with past climatic conditions, while current soil abiotic factors or root herbivore pressure did not show a clear association with root latex chemistry. Results were identical for natural and controlled conditions, suggesting heritable trait variation rather than environmental plasticity as underlying factor. C_LIO_LISynthesis. We conclude that climatic conditions likely play a major role in the evolution of root secondary metabolites. Direct abiotic effects are likely underlying this pattern, hinting at a novel role of root latex metabolites the tolerance of abiotic stress. C_LI

Gagea bohemica s. lat. is a morphologically and karyologically highly variable group with many morphologically similar "narrow" taxa currently considered as a single variable species. It is predominantly distributed in Mediterranean and warmer parts of temperate belt of Europe. The large-scale data on its cytogeography and population cytotype structure which could provide a basis for taxonomy is lacking, only scattered data on ploidy have been published from various parts of its range. In this study, we sampled 106 populations in broader Central Europe, the northeastern Balkan Peninsula and the northwestern Black Sea coast in order to analyse their ploidy level, genome size and pollen stainability. Two cytotypes, i.e., tetraploid (2n = 48) and pentaploid (2n = 60), were found in the study area using chromosome counting and flow cytometry, both in pure and mixed-ploidy populations. Pure pentaploid populations are mainly distributed in Austria, Czechia, northwestern Hungary and Slovakia while tetraploid cytotype in pure and mixed-ploidy populations forming two lineages which are concentrated into two disjunct geographical areas: a western lineage in Germany and Switzerland, and an eastern one in Bulgaria, southeastern Hungary, northern Greece, Romania, Serbia and Ukraine. The two lineages differ in their genome size regardless of their ploidy, indicating their independent origin. Analysis of pollen stainability using a modified Alexander stain revealed an unusual pattern with tetraploids having a lower pollen stainability (mean 44.29 %) than pentaploids (mean 70.70 %) but the western and eastern populations differed again from each other.

O_LICommon-environment experiments are important to study genetically-based phenotypic variation within and among plant populations. Such experiments can be performed in an experimental garden, greenhouse or climate chamber. However, phenotypic expression may be strongly affected by the environmental conditions and influenced by parental and storage effects. Hence, it is unclear if results from common-environment experiments are reproducible across multiple experimental setups. C_LIO_LIIn this study, we assessed the effects of three different growth facilities - outdoor garden, greenhouse, and climate chamber -, on phenotypic expression. We compared ancestral and descendant genotypes of the same population of Leontodon hispidus. We also evaluated differences in phenotypic expression between plants grown after one (F1) vs. two (F2) intermediate generations. C_LIO_LIWe observed strong differences among plants growing in different growth facilities. Furthermore, we found that descendants had larger rosettes than ancestors only in the greenhouse and they flowered later than ancestors exclusively in the climate chamber. We did not find significant differences between intermediate generations within the growth facilities. C_LIO_LIOverall, our study demonstrates that environmental variation among growth facilities can dictate the presence and magnitude of phenotypic differences. This implies that absence of evidence for phenotypic differences is not evidence of absence. Experimental systems should be carefully designed to provide meaningful conditions related to the research question. Finally, growing a second intermediate generation did not impact the genetic differences of ancestors and descendants within the facilities, supporting that only one intermediate generation may be sufficient to reduce detectable parental and storage effects. C_LI