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Fumana is a diverse genus of the Cistaceae family, consisting of 21 currently accepted species. In this study, nuclear (ITS) and plastid (matK, trnT‐L) molecular markers were used to reconstruct the phylogeny and to estimate divergence times, including 19 species of Fumana. Phylogenetic analyses (Bayesian Inference, Maximum Parsimony and Maximum Likelihood) confirmed the monophyly of Fumana and did not support the infrageneric divisions previously established. The results support four main clades that group species that differ in vegetative and reproductive characters. Given the impossibility to define morphological characters common to all species within the clades, our proposal is to reject infrageneric divisions. Molecular dating and ancestral area analyses provide evidence for a Miocene diversification of the genus in the north‐western Mediterranean. Ancestral state reconstructions revealed ancestral character states for some traits related to xeric and arid habitats, suggesting a preadaptation to the Mediterranean climate., This research has been supportedby the Spanish “Plan Nacional de I+D+I” project “Romero” [CGL2005–03912] and the Botanical Garden of the University of Valencia for permitting to use laboratory facilities. Meike Engelbrecht received a grant from the Spanish National Research Council (CSIC) [JAEPre 08 00758].

This work aims to discriminate among different species of the genus Cistus, using seed parameters and following the scientific plant names included as accepted in The Plant List. Also, the intraspecific phenotypic differentiation of C. creticus, through comparison with three subspecies (C. creticus subsp. creticus, C. c. subsp. eriocephalus and C. c. subsp. corsicus), as well as the interpopulation variability among five C. creticus subsp. eriocephalus populations was evaluated. Seed mean weight and 137 morphocolorimetric quantitative variables, describing shape, size, colour and textural seed traits, were measured using image analysis techniques. Measured data were analysed applying step-wise linear discriminant analysis. An overall cross-validated classification performance of 80.6% was recorded at species level. With regard to C. creticus, as case study, percentages of correct discrimination of 96.7% and 99.6% were achieved at intraspecific and interpopulation levels, respectively. In this classification model, the relevance of the colorimetric and textural descriptive features was highlighted, as well as the seed mean weight, which was the most discriminant feature at specific and intraspecific level. These achievements proved the ability of the image analysis system as highly diagnostic for systematic purposes and confirm that seeds in the genus Cistus have important diagnostic value.

Premise of the study Species differ in their temperature germination niche. Populations of a species may similarly differ across the distribution range of the species. Anticipating the impacts of climate variability and change requires understanding the differential sensitivity to germination temperature among and within species. Here we studied the germination responses of four hard-seeded Cistaceae seeders to a range of current and future temperatures. Methods Seeds were collected at sites across the Iberian Peninsula and exposed or not exposed to a heat shock to break dormancy, then set to germinate under four temperature regimes. Temperatures were varied daily and seasonally, simulating the temperature range across the gradient, plus an increased temperature simulating future climate. Time to germination onset and cumulative germination at the end of each season were analyzed for the effects of temperature treatments, seasons, and local climate (temperature of the germination period, Tgp) at each site. Key results Tgp was a significant covariate of germination in all species but Cistus populifolius. Temperature treatments significantly affected Cistus ladanifer, C. salviifolius, and Halimium ocymoides. Germination occurred in simulated autumn conditions, with little germination occurring at later seasons, except in unheated seeds of H. ocymoides. Exposure to a heat shock changed the sensitivity to temperature treatments and the relationships with Tgp. Conclusions Germination responses to temperature differ not only among species but also within species across their latitudinal range. The responses were idiosyncratic and related to the local climate of the population. This germination variability complicates generalizing the impacts of climate variability and climate change.

Demographic rates in plants are usually assumed to be more stage or size dependent than age dependent, and aging is therefore not considered in demographic models. However, little is known about the effect of age on demographic rates, as there still are few studies based on long-term individual-based plant population data that consider both individual age and size. In addition, little is known about how aging of individuals may affect population dynamics. We present analyses of demographic data for three populations of Fumana procumbens collected 1985–2013, on individuals with known year of germination. We modeled age- and size-dependence of the vital rates of survival, growth, fruiting probability, and fruit number using thin plate spline regressions, and constructed an age × size integral projection model (IPM) to project population-level effects of aging. We found strong correlations between age and vital rates in solely age-based vital rate models, where vital rates initially increased with age, after which they stabilized and, in some cases, eventually declined. In survival models with both age and size, the effects of age were statistically significant, whereas size effects were insignificant at two of the sites. For other vital rates, most of the effect of age could be explained by size alone. In addition, including the age effects on survival in the IPM led to lower population growth rates compared to predictions of a size-only IPM. These results illustrate that demographic senescence does occur in perennial plants, which has only been demonstrated clearly in a few recent detailed studies. Moreover, we show that population projections may be overly optimistic if they do not consider plant age. We conclude that the possibility of demographic senescence should be considered in demographic population models, such as those used in viability analyses of threatened species.

Leaf respiration in the dark and its C isotopic composition (δ(13) CR ) contain information about internal metabolic processes and respiratory substrates. δ(13) CR is known to be less negative compared to potential respiratory substrates, in particular shortly after darkening during light enhanced dark respiration (LEDR). This phenomenon might be driven by respiration of accumulated (13) C-enriched organic acids, however, studies simultaneously measuring δ(13) CR during LEDR and potential respiratory substrates are rare. We determined δ(13) CR and respiration rates (R) during LEDR, as well as δ(13) C and concentrations of potential respiratory substrates using compound-specific isotope analyses. The measurements were conducted throughout the diel cycle in several plant species under different environmental conditions. δ(13) CR and R patterns during LEDR were strongly species-specific and showed an initial peak, which was followed by a progressive decrease in both values. The species-specific differences in δ(13) CR and R during LEDR may be partially explained by the isotopic composition of organic acids (e.g., oxalate, isocitrate, quinate, shikimate, malate), which were (13) C-enriched compared to other respiratory substrates (e.g., sugars and amino acids). However, the diel variations in both δ(13) C and concentrations of the organic acids were generally low. Thus, additional factors such as the heterogeneous isotope distribution in organic acids and the relative contribution of the organic acids to respiration are required to explain the strong (13) C enrichment in leaf dark-respired CO2 .

Mediterranean shrublands are generally water-limited and fire-driven ecosystems. Seed-based post-fire regeneration may be affected by varying rainfall patterns, depending on species sensitivity to germinate under water stress. In our study, we considered the germination response to water stress in four species from several sites across the Mediterranean Basin. Seeds of species with a hard coat (Cistus monspeliensis, C. salviifolius, Cistaceae, Calicotome villosa, Fabaceae) or soft coat (Erica arborea, Ericaceae), which were exposed or not to a heat shock and smoke (fire cues), were made to germinate under water stress. Final germination percentage, germination speed and viability of seeds were recorded. Germination was modelled using hydrotime analysis and correlated to the water balance characteristics of seed provenance. Water stress was found to decrease final germination in the three hard-seeded species, as well as reduce germination speed. Moreover, an interaction between fire cues and water stress was found, whereby fire cues increased sensitivity to water stress. Seed viability after germination under water stress also declined in two hard-seeded species. Conversely, E. arborea showed little sensitivity to water stress, independent of fire cues. Germination responses varied among populations of all species, and hydrotime parameters were not correlated to site water balance, except in E. arborea when not exposed to fire cues. In conclusion, the species studied differed in germination sensitivity to water stress; furthermore, fire cues increased this sensitivity in the three hard-seeded species, but not in E. arborea. Moreover, populations within species consistently differed among themselves, but these differences could only be related to the provenance locality in E. arborea in seeds not exposed to fire cues.

Most habitat fragmentation studies have focused on the effects of population size on reproductive success of single species, but studies assessing the effects of both fragment size and connectivity, and their interaction, on several coexisting species are rare. In this study, we selected 20 fragments along two continuous gradients of size and degree of isolation in a gypsum landscape in central Spain. In each fragment, we selected 15 individuals of each of three dominant gypsophiles (Centaurea hyssopifolia, Lepidium subulatum and Helianthemum squamatum, 300 plants per species, 900 plants in total) and measured several reproductive traits: inflorescence number, fruit set, seed set and seed mass. We hypothesised that plant fitness would be lower on small and isolated fragments due to an interaction between fragment size and connectivity, and that response patterns would be species-specific. Overall, fragment size had very little effect on reproductive traits compared to that of connectivity. We observed a positive effect of fragment connectivity on C. hyssopifolia fitness, mediated by the increased seed predation in plants from isolated fragments, resulting in fewer viable seeds per capitulum and lower seed set. Furthermore, seed mass was lower in plants from isolated fragments for both C. hyssopifolia and L. subulatum. In contrast, few reproductive traits of H. squamatum were affected by habitat fragmentation. We discuss the implications of species-specific responses to habitat fragmentation for the dynamics and conservation of gypsum plant communities. Our results highlight the complex interplay among plants and their mutualistic and antagonistic visitors, and reinforce the often-neglected role of habitat connectivity as a key component of the fragmentation process.

Nomenclatural types are designated for the names of six taxa of Cistus (Cistaceae) described by Linnaeus, C. albi- dus, C. crispus, C. ladanifer, C. monspeliensis, C. populifolius, and C. salviifolius. Original material from LINN and UPS was critically examined, as well as other information in the protologues. Data relevant for typification are discussed, and lectotypes are selected to maintain traditional or current use of the concerned names.

The pollen morphology of 11 species (including two subspecies and two varieties) belonging to two genera (Helianthemum and Fumana) of the family Cistaceae in Egypt was studied using light and scanning electron microscopy. Pollen grains of the studied taxa were found to be radially symmetrical and tricolporate. Pollen size, shape, apertures, and exine ornamentation characteristics were valuable parameters among the studied taxa. The largest pollen size was recorded in H. salicifolium and the smallest one observed in H. kahiricum subsp. schweinfurthii. Pollen shape in the Egyptian taxa varied from (sub-)prolate to prolate spheroidal, but F. arabica is different in having sub-oblate grains. The pollen data confirm that H. lippii and H. sessiliflorum are very closely related species. Pollen sculpture was useful in distinguishing between H. vesicarium var. vesicarium and H. vesicarium var. ciliatum. Three main pollen types of exine ornamentation were recognized: retipilate; reticulate to verrucate; and striate. Based on palynological data, a key for the studied taxa is suggested.

In a recent study (American Journal of Botany 97: 730-737), we described the first case of a tripartite association in natural conditions among a holoparasitic plant (Cytinus), its host Cistaceae species, and mycorrhizal fungi at an anatomical level. In a letter to the editor, Brundrett (American Journal of Botany 98: 595-596) commented on our manuscript and questioned our conclusions, arguing that they are not adequately supported by the data. We reject this point of view and believe that the controversy has arisen because of the parasitic way of life of Cytinus. We maintain and demonstrate that there is enough evidence in the data that we presented to confirm the existence of mycorrhizal associations in the Cytinus-Cistaceae complex, supporting the functionality of the tripartite association. Most holoparasitic plants have been considered as nonmycorrhizal. However, it is not advisable to be categorical in drawing conclusions about the mycorrhizal status of a group of plants that has not been fully studied.

This study investigated the phylogeographic structure of Cistus ladanifer, in order to locate its Quaternary refugia, reconstruct its recolonisation patterns and assess the role of geographical features (mountain ranges, rivers and the Strait of Gibraltar) as barriers to its seed flow and expansion through the Western Mediterranean. Thirty-eight populations were screened for length variation of polymorphic chloroplast simple sequence repeats (cpSSRs). Statistical analyses included estimation of haplotypic diversity, hierarchical analysis of molecular variation (AMOVA) and fixation indices. Mantel tests, SAMOVA and BARRIER analyses were applied to evaluate the geographical partitioning of genetic diversity across the entire species range. Pollen data from bibliography were used to complement molecular inferences. Chlorotype diversity within populations was similar throughout the natural range of C. ladanifer (mean haplotypic diversity = 0.32). High differentiation among populations was estimated (GST = 0.60). Our data suggest that the barriers of the Strait of Gibraltar and the Betic ranges may have favoured the divergence during glacial periods of four different lineages of populations inferred with SAMOVA. The main northward colonisation of in the Iberian Peninsula occurred from refugia in southwest Iberia. This process may have been influenced by human activities (forest clearance, livestock grazing and even commerce) in the Iberian Peninsula. In contrast, populations in the Betic area have conserved a specific haplotype.

Introduction – Cistaceae is a large family of shrubs widely spread over the Mediterranean area. It includes Helianthemum, Halimium and Cistus genus. Cistus genus contains approximately 20 species distributed in three subgenus. The essential oil of Cistus species has been thoroughly studied, but the polyphenolic composition of the aerial parts of the different Cistus species needs further characterisation. Objective – To perform a comparative analysis of the qualitative and quantitative polyphenolic composition of the aerial parts of the most commonly distributed Spanish Cistus species in order to find a relationship between chemotype and subgenus. Methodology – Thirteen aqueous extracts derived from 10 different Cistus species were analysed by using HPLC with diode array-detection coupled to electrospray ion trap mass spectrometry technique (HPLC-DAD-ESI-MS/MS). Their major compounds were identified and ellagitannins were quantified. Principal component analysis (PCA) was performed on the most relevant compounds to find out the statistical association between chemotype and variety. Results – Three main groups of compounds were found, i.e. ellagitannins, flavonoids and phenolic acids derivatives. The polyphenolic profile was specific for each species, although the abundance of some compounds also varied depending on the soil type. Whereas C. ladanifer, C. salviifolius, C. populifolius and C. libanotis were specially rich in ellagitannins, C. clusii, C. laurifolius and C. monspeliensis contained significant amounts of flavonoids and much less ellagitannins. In contrast, C. crispus, C. incanus and C. albidus showed a polyphenolic profile mostly based on flavonoids. PCA analysis showed a strong relationship between Cistus subgenus and its chemotype based on the most relevant water-soluble polyphenolic compounds. Conclusions – Chemical composition of the leaves' aqueous extracts from plants belonging to the Cistus genus is strongly related to their subgenus, in agreement to previous taxonomical and phylogenetic divisions. In contrast, soil and climate are less influencing factors. Leucocistus and Halimioides subgenus showed a higher content in ellagitannins. However, Cistus subgenus had higher flavonoid content. Copyright © 2011 John Wiley & Sons, Ltd.

According to life-history theory, reproductive investments involve costs in terms of growth, future fecundity, and/or survival. However, studies to date have often failed to detect costs of reproduction, with survival costs among the less documented. We investigated the cost of reproduction in Helianthemum squamatum (Cistaceae), a short-lived perennial of semiarid Mediterranean environments. After experimental fl ower removal, we evaluated next season ’ s growth, reproduction, and survival of the plants. We also monitored an indicator of plant physiological status ( F v / F m ) and leaf nutrient concentration at key phenological stages during reproduction. Survival rate in deblossomed plants was signifi cantly higher than in control plants. As far as we know, this is the fi rst experimental evidence of a survival cost of reproduction in a perennial plant. In contrast, no cost to growth or reproduction was found during the next season, and no signifi cant differences in F v / F m or leaf nutrients were found between control and deblossomed plants. Helianthemum squamatum ’ s success in semiarid Mediterranean ecosystems seems to rely on a persistent seed bank, combined with a sustained high reproductive output at the expense of survival. We conclude that this strategy might be more common than previously thought among short-lived shrubby plants growing in stressful Mediterranean areas.

Aim There are few biogeographical and evolutionary studies that address plant colonization and lineage origins in the Mediterranean. Cistus serves as an excellent model with which to study diaspore dispersal and distribution patterns of plants exhibiting no special long-distance dispersal mechanisms. Here we analyse the pattern of genetic variation and divergence times to infer whether the African–European disjunction of C. ladanifer L. is the result of long-distance dispersal or of vicariance events. Location Principally the Western Mediterranean region, with a focus on the Strait of Gibraltar. Methods We used DNA sequence phylogenetic approaches, based on plastid (rbcL/trnK-matK) and nuclear (ITS) sequence data sets, and the penalized likelihood method, to date the diversification of the 21 species of Cistus. Phylogenetic relationships and phylogeographical patterns in 47 populations of C. ladanifer were also analysed using two plastid DNA regions (trnS-trnG, trnK-matK). These sequence data were analysed using maximum parsimony, Bayesian inference and statistical parsimony. Results Dating estimates indicated divergence dates of the C. ladanifer lineage in the Pleistocene. Eight nucleotide-substitution haplotypes distributed on the European (four haplotypes) and African (five haplotypes) sides of the Strait of Gibraltar were revealed from C. ladanifer sequences. Both the haplotype network and the phylogenetic analyses depicted two main Cistus lineages distributed in both Europe and North Africa. An Iberian haplotype forms part of the North African lineage, and another haplotype distributed on both continents is related to the European lineage. Haplotype relationships with respect to outgroup sequences supported the hypothesis that the centre of genetic diversity is in northern Africa. Main conclusions Based on lineage divergence-time estimates and disassociation between geographical and lineage haplotype distributions, we inferred at least two intercontinental colonization events of C. ladanifer postdating the opening of the Strait of Gibraltar (c. 5 Ma). This result supports a hypothesis of long-distance dispersal rather than a hypothesis of vicariance. We argue that, despite limited dispersal abilities, preference for disturbed habitats was integral to historical colonization after the advent of the Mediterranean climate (c. 3.2 Ma), when Cistus species diverged and became established as a dominant element in the Mediterranean scrub.

Mediterranean ecosystems are hotspots of species richness where fire is one of the key processes influencing their structure, composition and function. Post-fire seedling emergence constitutes a crucial event in the life cycle of plants and species-specific temporal and spatial patterns of seedling emergence have been hypothesized to contribute to the high diversity in these ecosystems. Here we study the temporal and spatial patterns of seedling emergence observed for the four dominant species (Cistus albidus, Ulex parviflorus, Helianthemum marifolium, Ononis fruticosa) after an experimental fire in a Mediterranean gorse shrubland. In a first analysis we compared the timing of emergence of each species using the Kaplan-Meier method. The spatial component of seedling emergence and the spatiotemporal relationship between different cohorts of the same species were analyzed using recent techniques of spatial point pattern analyses. We found a bimodal temporal pattern of emergence. Emergence of Cistaceae species (H. marifolium and C. albidus) occurred predominantly early after the fire while Fabaceae (O. fruticosa and U. parviflorus) emerged mainly during the following autumn. Individually, all species showed an aggregated spatial pattern and, when testing for pair interactions, we found that the clusters of individual species were spatially segregated. Additionally, the clusters of individual species showed an internal spatial structure where seedlings of different cohorts were spatially segregated. Theoretical models predict that these patterns will promote species coexistence. We identified a number of mechanisms that all have the potential to contribute to the observed pattern formation. However, the potential interaction among these mechanisms are complex and not easy to predict. Our analyses take a significant step forward in studying seedling emergence in fire prone ecosystems since, to our knowledge, this is the first time that both spatial and temporal patterns of all dominant species have been studied together.

Summary • Speciation via race formation is an important evolutionary process in parasites, producing changes that favour their development on particular host species. Here, the holoparasitic plant Cytinus, which has diverse host species in the family Cistaceae, has been used to study the occurrence of such races. • Amplified fragment length polymorphism (AFLP) analyses were performed on 174 individuals of 22 populations parasitizing 10 Cistaceae species in the Western Mediterranean basin. • Neighbour-joining, multivariate ordination analyses, and individual-based Bayesian analyses, clustered Cytinus populations into five well-characterized genetic races that, overall, agreed with the taxonomic sections of their hosts. In the AMOVA, among-races differences accounted for almost 50% of the genetic variation. The isolation-by-distance model was not supported by a Mantel test among Cytinus populations (r = 0.012; P = 0.456). All races showed low within-population genetic diversity, probably as a result of restricted pollen flow aggravated by flowering asynchrony, restricted seed dispersion, or stochastic processes. • The genetic differentiation among the five races of Cytinus is congruent with the view that these races are well-characterized lineages that have evolved independently as a result of selective pressures imposed by their hosts. This pattern, with genetically distinctive groups associated with the infrageneric sections of the host species, has not been reported previously for parasitic angiosperms.

The composition of the essential oils obtained from the whole flowering tops and from isolated flowers and leaves of Cistus albidus L. (Cistaceae) has been investigated. The three essential oils were constituted mainly by sesquiterpene derivatives, but they showed quite different compositions. In the flowering tops and flowers the main constituents were α-zingiberene, α-cadinol and ar-curcumene, while in the leaves the principal compounds were α-cadinol, juniper camphor, germacrene D and spathulenol. Furthermore, the volatiles emitted in vivo by whole flowers, petals, sepals, pollen and leaves were investigated by means of SPME. Also in these analyses, sesquiterpenes were the main constituents but with a clear dominance of hydrocarbon derivatives. The whole flowers, petals, sepals and leaves of C. albidus showed a similar emission pattern of volatiles, whereas the pollen showed a very different profile. Copyright © 2006 John Wiley & Sons, Ltd.

Summary Although decline of cork (Quercus suber) and holm oak trees (Quercus rotundifolia) has been described in Portugal in the late years of the 19th century, its development has become a motive of high concern during the last two decades. The presence of Phytophthora cinnamomi in cork and holm oak stands was surveyed in four different regions of the country (Tras-os-Montes, Alentejo, Ribatejo and Algarve) during 1995–98. Tree decline severity, sudden death and site characteristics were assessed in 56 sites representing varied conditions. The pathogen was isolated from oak roots and rhizosphere samples in 27 of those places. Other plant species from natural vegetation were sampled in three active disease centres. This survey showed that 56% of the surveyed species of shrub flora were infected with P. cinnamomi, which was detected mainly on species belonging to the families Ericaceae, Cistaceae and Leguminosae. Recovery of P. cinnamomi was more frequent in shallow soils (Leptosols and complex Leptosols and Luvisols). These soils are more common in the south (Algarve), where decline has a high impact. Soils with low fertility and low mineral nutrient levels, particularly phosphorus, seemed to favour infection. Site aspect and topographic tree situation were also evaluated. Sites facing south showed higher occurrence of P. cinnamomi, which was also more frequent in slopes and valleys than on hilltops. In Algarve, a relationship could be established between the crown status and the presence of P. cinnamomi in roots and rhizosphere. Different morphotypes of P. cinnamomi could be distinguished in vitro, and their occurrence in the field was correlated with particular site characteristics. Further research needs and management strategies to limit the extension of the disease are discussed. Resume Le deperissement des chenes verts et chenes liege, decrit au Portugal depuis la fin du XIXeme siecle, est devenu tres preoccupant au cours des deux dernieres decennies. La presence de Phytophthora cinnamomi dans les peuplements de chenes verts et chenes liege a eteetudiee dans 4 regions du Portugal (Tras-os-Montes, Alentejo, Ribatejo et Algarve) pendant la periode 1995–98. La severite du deperissement, les mortalites brutales et les caracteristiques stationnelles ont ete relevees dans 56 sites representant des conditions variees. Le pathogene a ete isolea partir d’echantillons de racines de chenes ou de la rhizosphere dans 27 de ces sites. D'autres especes de plantes de la vegetation naturelle ont eteetudiees dans trois zones particulierement affectees par la maladie. Neuf des seize especes testees se sont averees infectees, particulierement dans les familles Ericaceae, Cistaceae et Leguminosae. P. cinnamomi a ete plus frequemment isole dans des sols peu profonds (Leptosols et complexes Leptosols + Luvisols). Ces sols sont plus communs dans le Sud (Algarve) ou le deperissement a un impact important. Les sols a faible niveau de fertilite et d’elements mineraux, particulierement pour le phosphore, semblent favoriser l'infection. L'effet de l'orientation des sites et de la situation topographique des arbres a egalement eteetudiee. Les sites exposes au sud, les pentes et les vallees presentent les plus fortes frequences de P. cinnamomi. En Algarve, une relation a pu etre etablie entre le statut du houppier et la presence de P. cinnamomi dans les racines et la rhizosphere. Differents morphotypes de P. cinnamomi ont pu etre definis in vitro, dont la presence sur le terrain est correlee avec certaines caracteristiques stationnelles. Les besoins de recherche et les strategies de gestion pour limiter l'extension de la maladie sont discutes. Zusammenfassung Das Absterben von Korkeichen (Quercus suber) und von Rundblattrigen Eichen (Q. rotundifolia) in Portugal wurde bereits am Ende des 19. Jahrhunderts beschrieben, in den letzten beiden Jahrzehnten hat diese Krankheit jedoch stark zugenommen. In vier unterschiedlichen Regionen Portugals (Tras-os-Montes, Alentejo, Ribatejo und Algarve) wurde 1995–98 das Vorkommen von Phytophthora cinnamomi in Bestanden dieser Baumarten untersucht. An 56 Standorten, die unterschiedliche Umweltbedingungen reprasentieren, wurden die Krankheitsintensitat und das plotzliche Absterben der Baume sowie Charakteristika der Standorte erfasst. An 27 dieser Standorte wurde das Pathogen aus Wurzeln und Rhizospharenproben isoliert. In drei aktiven Krankheitsherden wurden auch andere Pflanzenarten aus der naturlichen Vegetation beprobt. Hierbei waren 56% der Straucharten von P. cinnamomi befallen (hauptsachlich Ericaceae, Cistaceae und Leguminosae). Phytophthora cinnamomi kam haufiger in flachgrundigen Boden vor (Leptosole und Komplexe aus Lepto- und Luvisolen). Diese Bodentypen finden sich haufiger in Sudportugal (Algarve), wo die Krankheit sehr stark auftritt. Nahrstoffarme Boden, insbesondere solche mit niedrigem Phosphorgehalt, scheinen die Infektion zu begunstigen. Bei der Untersuchung wurden auch die Exposition der Standorte und die topographische Lage der Probebaume berucksichtigt. Auf sudexponierten Lagen, wie auch in Hang- und Tallagen (im Vergleich zu Kuppen) kam P. cinnamomi haufiger vor. In der Algarve konnte eine Beziehung zwischen dem Kronenzustand und dem Vorkommen von P. cinnamomi in den Wurzeln und der Rhizosphare festgestellt werden. In vitro konnten verschiedene Morphotypen von P. cinnamomi unterschieden werden, deren Vorkommen im Feld mit bestimmten Standortfaktoren korreliert war. Der weitere Forschungsbedarf und mogliche Managementstrategien zur Begrenzung der Krankheitsausbreitung werden diskutiert.

The typification of the names of four species originally described by Desfontaines and reported in the literature for Calabria (S Italy) is discussed. Lectotypes from the Desfontaines Herbarium (P) are designated for Aristida adscensionis subsp. coerulescens (Desf.) Bourreil & Trouin ex Auquier & J. Duvign. (= A. coerulescens Desf., Poaceae), Helianthemum sessiliflorum (Desf.) Pers. (= Cistus sessiliflorus Desf., Cistaceae), Ranunculus spicatus Desf. (Ranunculaceae), and Salsola oppositifolia Desf. (Chenopodiaceae).

Summary • We studied the effects of Cistus albidus leaf leachates on nitrogen-cycling processes in two siliceous soils (granite and schist) and one calcareous soil. We compared those effects with gross N-transformation rates in soils sampled underneath Cistus. • Soils amended with leachates and soils sampled under Cistus had higher NH4+ immobilization and lower nitrification compared with control soils. Gross N mineralization increased under Cistus but decreased in soils amended with leachates. These effects were especially strong in granite soil. • To determine whether phenolic compounds were causing those effects, we incubated granite soils with leachate and a leachate fraction containing only nonphenolic compounds. Nonphenolic compounds increased NH4+ immobilization and decreased gross nitrification, while decreases in gross N mineralization were estimated to be caused by phenolic compounds. • Our results show that although phenolic compounds leached from green foliage changed gross N mineralization, their effects on net N rates were eclipsed by the changes produced by polar nonphenolic compounds such as carbohydrates. Plant nonphenolic compounds may drive N cycling under Cistus.

Summary Roe deer feeding habits were studied in the western Alps during the summer season using the faecal analysis method. The diet of cattle grazing in the same area was also investigated and the trophical niche overlap between the two species was determined. The roe deer diet was found very variable and mostly composed of dicotyledons, with Leguminosae and Cistaceae as prevalent species. Monocotyledons, mainly represented by Graminaceae, were consumed to a lesser extent. A significant preference was observed for Cistaceae and other dicotyledons whereas a significant refuse was observed for Graminaceae and Asteraceae. These data confirmed the roe deer's behaviour to select food with a better nutritive value. Despite the differences between the cattle and roe deer's diets, the trophical niche overlap was quite high. This can be explained by the homogeneity of the plants covering the whole area which probably limited food selection by the roe deer.

Summary 1. This paper presents a method for modelling unimodal flowering phenology based on fitting data to an exponential sine function with a minimum number of parameters. 2. Such parameters have the advantage of being direct surrogates for the most relevant features of any phenology (start, duration, intensity, skewness and length of the tails). 3. The use of the proposed function is exemplified using flowering data collected from populations of five Cistaceae species (four from the genus Cistus and one from Halimium). 4. The fitted models account for a large part (> 90%) of the variance in the data, and their parameters are easily interpreted in ecological terms.

In the current study, antioxidant, antibacterial activities, and the phenolic compositions of extracts from Helianthemum canum L. Baumg. (Apiaceae) aerial parts were investigated for the first time. The H. canum was extracted with 70% methanol (HCMeOH) and water (HCW). Both extracts were determined by total phenolic contents (3 mg/ml), flavonoids (1.5 mg/ml), flavonols (1.5 mg/ml), qualitative-quantitative compositions, iron (II) chelation activities (0.1 - 5 mg/ml), free radical scavenging activities (DPPH• : 0.01 - 0.6 mg/ml and ABTS+• : 0.125 - 0.5 mg/ml) and the effect upon inhibition of β-carotene/linoleic acid co-oxidation (1 mg/ml). The peroxidation level was also determined using the thiobarbituric acid method (0.01 - 1.5 mg/ml). The results of the activity tests given as IC50 values were estimated from non-linear algorithm and compared with standards. Antibacterial activities of extracts and standards were evaluated against Gram-negative and -positive ten standard strains using disc diffusion and broth microdilution methods. The MIC results (312.5 - 2500 μg/ml) against tested microorganisms varied from 625 to 2500 μg/ml. In HPLC analysis, 3,5-dihydroxybenzoic acid was found as the main substance in both extracts. These results showed that HCMeOH was richer in phenolic compounds (284.13 ± 0.30 mg GAE/g extract) from HCW (244.55 ± 0.35 mg GAE/g extract). In conclusion, H. canum extracts showed in vitro antibacterial and antioxidant activities.

Fumana ericifolia belongs to the family Cistaceae, in which all perennial species previously studied have been reported to be self-incompatible and xenogamous. Here we show that F. ericifolia is self-compatible and autogamous. Its flowers last only four to eight hours and produce a small amount of pollen and ovules. Self-pollination depends on changes in the relative position of the stigma and the anthers, triggered by the abscission of the petals; this in turn causes closing of the sepals, which push the anthers onto the stigma. Pollen remains highly viable and germinable, and the stigma keeps its receptivity several hours after the loss of the petals. Hand pollination treatments revealed that fruits are produced both in selfed and crossed flowers. The germination of pollen grains on the stigma, the rate of pollen tube growth along the style, and the penetration into the ovules were similar in self-and cross-pollinations; also, there were no significant differences in fruit set, seed set and weight of seeds. Thus, we report the first evidence of autogamy in a woody Cistaceae and suggest that selfing may ensure reproductive success when pollinators are limited.

The distribution of vestured pits in the secondary xylem of all major groups of Malvales s.l. is investigated and compared with recent circumscriptions and phylogenetic insights of the order. While the monophyly of the core Malvales, including Bombacaceae, Malvaceae s.str., Sterculiaceae, and Tiliaceae, is supported by the lack of vestured pits, the character is consistently present in three malvalean alliances that are well supported based on molecular data: (1) Bixaceae, Cochlospermaceae, and Diegodendraceae; (2) Cistaceae, Dipterocarpaceae s.l. (including Monotaceae), and Sarcolaenaceae; and (3) Thymelaeaceae s.l. (including Aquilariaceae and Gonystylaceae). Vestured pits are absent in other malvalean taxa such as Petenaea, Muntingiaceae, Neuradaceae, and Sphaerosepalaceae. Families that are now excluded from the order, such as Dirachmaceae, Elaeocarpaceae, and Huaceae also have non-vestured pits. Rudimentary vestures in Plagiopteraceae, however, do not necessarily indicate a malvalean affinity.

Rupicolous plants coming from a single Balearic locality are described as a new species, Helianthemum scopulicolum. The plant is diploid (2n=20) and belongs to Helianthemum subgenus Helianthemum sect. Helianthemum. On morphological grounds, Helianthemum scopulicolum is related to some members of the H. apenninum aggregate, notably H. apenninum s.l., H. asperum and H. violaceum. However, the new species can be distinguished on the basis of leaves green, shining, glabrescent on the adaxial surface, deciduous short bracts, glabrescent inner sepals lacking long setae and pink-purple flowers.

Pollen of Setchellanthus caeruleus was studied by light, scanning electron, and transmission electron microscopy and found to differ profoundly from that of potentially related families such as the Brassicaceae, Capparaceae, Caricaceae, Cistaceae (Helianthemum canadense, here re-investigated and found to have pollen shed in tetrads), and Limnanthaceae. These differences support the segregation of S. caeruleus into a new separate family.

Seed dispersal of dry-fruited shrubs has received little attention in Mediterranean areas despite their frequency in the vegetation and the consideration given to the dispersal of fleshy-fruited shrubs in the area. Red deer faeces has recently been found to contain large numbers of seeds from one of the most common shrubs of this group, gum cistus Cistus ladanifer, although its importance in the reproduction of the species is unknown. This study examines the role of the red deer as an effective disperser of C. ladanifer. For this purpose, we quantify i) the C. ladanifer seed content in red deer dung over a year, ii) the seed shadow generated by the red deer with their faeces during the same period, and iii) the ability of the dung-borne seeds to germinate and establish as seedlings under field conditions within five years following excretion. The results reveal an extremely high seed content of the species in red deer dung (up to 80.5 ± 41.9 germinable seeds g -1 ), which is virtually confined to the summer (July-August), when we estimate that a red deer defecates up to 24 000 seeds of the species per day. Furthermore, red deer mainly deposit gum cistus seeds amongst plant formations lacking the species: over the year, red deer excrete

Bioassay-guided fractionation of the methanol extract of aerial parts from Helianthemum glomeratum afforded five antiprotozoal flavonol glycosides: tiliroside, kaempferol-3-O-(3″,6″di-O-E-p-coumaroyl)-βd-glucopyranoside, astragalin, quercitrin and isoquercitrin. The invitro antiprotozoal assay showed that tiliroside was the most potent antiamoebic and antigiardial compound with IC50 values of 17.5 µg/mL for Entamoeba histolytica and 17.4 µg/mL for G. lamblia. Isoquercitrin showed selectivity against E. histolytica (IC50 14.7 µg/mL) and quercitrin toward G. lamblia (IC50 24.3 µg/mL). All isolated compounds were less active than metronidazole and emetine, two antiprotozoal drugs used as positive controls. Copyright © 2006 John Wiley & Sons, Ltd.

The essential oil of Cistus ladaniferus L., obtained from plants of Spanish origin grown in Corsica, was investigated by 13C-NMR spectroscopy (identification of components) and GC (quantification). First, a bulk sample was analysed and 45 constituents were identified. The main components were α-pinene (39%), viridiflorol (11.8%), ledol (3.3%) and bornyl acetate (3.1%). The occurrence of cyclosativene, γ-cadinene, (E)-β-farnesene and β-eudesmol in the essential oil of Cistus ladaniferus is reported here for the first time. Then, in order to study the chemical variability of individual oils, we examined 20 samples. α-Pinene (11.1–47.4%) was the most abundant component in 18 of the 20 samples, followed by trans-pinocarveol (4.4–10.9%) and viridiflorol (4.7–10.7%). Two samples exhibited a different chemical composition, not as yet described, characterized by the predominance of viridiflorol (20–22.6%), ledol (6.4–6.7%) and trans-pinocarveol (5.4–8.6%). © 1997 John Wiley & Sons, Ltd.

Several organic matter fractions together with biological and biochemical parameters that might serve as markers of microbial activity were determined in an area previously dedicated to agriculture but where the soils had been abandoned for different lenghts of time (3 to 45 yr). Recently abandoned agricultural soils showed lower organic matter levels than soils not exposed to anthropic activity (natural soils). During the years immediately following abandonment the soils show lower levels of total organic C, humic substances and labile fractions of organic matter than natural soils. Soils abandoned for longer than 15 yr begin to recover their organic fractions after the appearance of spontaneous vegetation. The lower slopes appear to accumulate a greater quantity of total organic C and some labile fractions of C, such as water soluble C. Soil abandonment has a negative influence on soil microbial activity, biomass C and oxidoreductases such as dehydrogenase and catalase, although these values begin to rise again after several years. Soils abandoned for long periods of time and in the process of recovery show higher oxidoreductase values than natural soils. The activity of hydrolases belonging to the N, C, and P cycles (ureases and proteases, β-glucosidase, and phosphatase) point to the negative influence of the agricultural practices, indicating that human activity does not favor adequate establishment of the cycles of these important nutrients. The cessation of agricultural activity leads to the recovery of soil hydrolase activities. Except in isolated cases, the hydrolase activities values determined did not appear to be affected by the position on the slope of the plot from which the samples were taken.

The annual cycle of vegetative growth in the Mediterranean shrub Halimium halimifolium (Cistaceae) sub- jected to simulated and natural browsing on the stabilized sands of Donana National Park (SW Spain) is described. In a drier area without herbivory (Monte Intermedio) plants were subjected to different intensities of clipping. In a more humid area with high herbivory pressure (Monte Negro) plants were isolated by cages. Plants were monitored monthly from Febru- ary to November 1994. Vegetative growth starts in March and ends in June or July, according to temperature and water availability. Plants intensely clipped and plants subjected to natural browsing responded maximally regarding shoot length, and number of leaves on main shoots and branches. Clipped plants, however, did not reach the height and cover of controls.

The names Cistus ericoides Cav. and C. laevis Cav. are typified. These names apply to two species, currently classified within the genus Fumana (Dunal) Spach, but the names have been frequently misapplied and both of thempose typification problems. The type specimen of the first has not been found. Thus an illustration is chosen as type and an epitype designated. The original material of C. laevis comprises a mixture of two different species. One element is selected to clarify the application of this binomial.

Helianthemum speciosum, sp. nov., from gypsum outcrops in north-eastern Somalia, is described and illustrated. H. stipulatum is recorded for the first time from Somalia and Yemen.

— A bicyclic diterpene triol with a new rearranged labdane carbon skeleton was isolated from the aerial parts of Halimiumviscosum (Willk.) Pinto da Silva (S. Joa˜o da Pesqueira). Its structure was established by FAB MS and two-dimensional NMRexperiments ( 1 H/ 1 H, 1 H/ 13 C) and its stereochemistry by NOE and X-ray study. © 2002 Elsevier Science Ltd. All rights reserved. Labdane diterpenes with a [4.3.0]nonane ring B sys-tem are quite rare in the literature. Compound I iso-lated from Gypothamun pinifolium 1 a -hydroxyketonewith an acetyl group on C-7 of the enantiomericseries and Chapaecoderins B and C ( II and III ) iso-lated from Echinodorus macrophillus 2 with a buteno-lide ring are between them.In our studies of Cistaceae components of the IberianPeninsulae, we have isolated from the aerial parts of Halimium viscosum (Willk.) P. da Silva 3–6 bicyclicditerpenes with labadane or halimane skeleton or tri-cyclic diterpenes as valparane and valparolane.The room temperature ethyl acetate extract of

Volatile components of Cistus ladanifer leaves from the north of Portugal were analysed by gas chromatography–mass spectrometry (GC–MS), gas chromatography–FID and preparative gas chromatography coupled to a sniffing system. Eighteen compounds were identified and among those, the norisoprenoid 2,6,6-trimethylcyclohex-2-enone was isolated by preparative-GC and identified as an important Cistus ladanifer constituent by EI mass spectrometry and NMR spectroscopy. Copyright © 1999 John Wiley & Sons, Ltd.

Amplified fragment length polymorphism and inter simple sequence repeat markers were used to assess the genetic structure of Cistus ladanifer and its genetic differentiation from co-occurring Cistus species. Clear genetic differentiation was found between two populations corresponding to the morphological description of Cistus palhinhae and the 23 Cistus ladanifer populations analyzed. However, the magnitude of differentiation (DICE coefficients > 0.98) appears to be more in agreement with the taxonomic designation of Cistus ladanifer ssp. sulcatus, which has been proposed by some authors, and not C. palhinhae. Dendrogram analysis of the genetic relationships among Cistus ladanifer, Cistus populifolius, Cistus monspeliensis, Cistus crispus, Cistus libanotis, Cistus salvifolius and Cistus albidus, with Halimium halimifolium as an outgroup, showed two main clusters. Taxa composition of these clusters concurs with the taxonomic classification proposed for Iberian species on the basis of flower color. One cluster comprised species with pink flowers (C. crispus and C. albidus, P = 81.3%) classified into the subgenus Cistus, and the other cluster contained the remaining five species (P = 77.9%) that have white flowers and are classified into two subgenera, Leucocistus (C. ladanifer, C. populifolius, C. salvifolius and C. monspeliensis) and Halimioides (C. libanotis). Within the subgenera Leucocistus, C. ladanifer was found to be distinct and can be separated into the section Ladanium, while the remaining species that are grouped together in a branch (P = 74.8%) can be separated into the section Ledonia.

Cistus albanicus is a white-flowered, characteristic endemic of the Albanian and N. Greek serpentine areas, mostly growing in black fir woods in the mountains, between 1000 and 1500 m of altitude. It is the youngest among the recognized cistus species and, judging from its natural habitat, the most hardy one. It was first collected just over 100 years ago, but authors either misunderstood it as a hybrid or else failed to validate (or indeed publish) the names they envisaged for it. The situation changed with the posthumous validation of Warburg's manuscript name C. albanicus by Heywood, in 1968, its subsequent adoption in Flora europaea (Tutin & al., Fl. Eur. 2: 283. 1968), and the disentangling of its history, taxonomy and ecology by Greuter (in Ann. Mus. Goulandris 2: 35-47. 1974). The species is now generally adopted, under that name, in the relevant literature, including Demiri (Fl. Ekskurs. Shqiper.: 320 & fig. 1542. 1983) and Greuter & al. (Med-Checklist 1: 315. 1984). It is cultivated on a small scale as an ornamental and shows considerable promise. The two first collections of this species, by Sintenis in 1896 in Greek Thessaly and by Baldacci in 1897 in N. Albania, were interpreted by the monographer Grosser (in Engler, Pflanzenr. 14: 30. 1903) as corresponding to the hybrid Cistus monspeliensis L. x C. "villosus" (i.e., C. creticus L.). Grosser also provided a Latin description under that hybrid formula. The actual hybrid with this parentage is apparently extremely rare, having so far only been collected three or four times in Corsica, where it has probably again disappeared. Litardiere (I.c.), when accounting for this hybrid in Briquet's Prodrome de la flore corse, on the basis of sterile material collected by Thellung in 1909 and 1911, gave it the new name C. xsintenisii, which he validated by reference to Grosser's Latin description. What little use there has been of that name (e.g., Gamisans & Jeanmonod, Cat. P1. Vasc. Corse, ed. 2: 153. 1993) is in the sense of the Corsican hybrid, which has very recently been newly described and named as C. xconradiae Demoly (in Biocosme Mesogeen 13: 19. 1996). In so doing, Demoly (I.c.) correctly chose one of the two collections cited by Grosser to typify Cistus sintenisii (see the Code, Art. 7.7). In fact, he selected it so as to make C. sintenisii and C. albanicus homotypic. Unless conservation is granted, C. sintenisii, a name that has been neither widely nor persistently used (Art. 57), will displace C. albanicus.

The development of Cistus incanus was explored in a dark basaltic soils and a calcareous terra—rosa, in relation to mycorrhizal establishment. Plants transplanted to the laboratory degenerated in native dark basaltic soils and in sterilized terra—rosa, where infections with mycorrhizal fungi did not occur. They grew in calcareous terra—rosa, where mycorrhizae developed. Successful development of C. incanus in unfertilized soils depended on ectomycorrhizae; infection and could be demonstrated several weeks after germination. Plants developed without mycorrhizae in both soils when irrigated with a complete nutrient solution. We conclude that when mycorrhizae are absent, C. incanus plants degenerate in unfertilized soils because of a mineral—nutrient deficiency. We suggest that absence of C. incanus and possibly some other batha—forming plants from dark basaltic soils in Israel is related to failure of ectomycorrhizal development in these soils. See full-text article at JSTOR