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Modern high quality nursery trees pruning as knipboom grow and crop significantly better during the first years after planting in the orchard. High quality nursery trees perform better in the first years after plantation in the orchard than average or low quality nursery trees. Nurserymen are focused on production of such trees in the shortest time (one year). However, fruit tree species and varieties differ in their abilities to produce these trees. The goal of this work was to increase the quality and branching of one-year-old nursery trees at two plum and two sweet cherry varieties by the treatments of 12 different preparations of plant growth regulators (PGRs). Before lifting, branching and trunk parameters were recorded. Data showed that Ethephone+Putrescine+GA4+7 and Ethephone+Putrescine+6-BAP significantly increased almost all parameters at both plum varieties. Both sweet cherry varieties were sufficiently branching with Globaryl+epibrassinolide treatment, however the lateral shoots of ‘Celeste’ sweet cherry variety were of low quality. The same was observed after treatment with Progerbalin+4-CPPU+Putrescine. Sweet cherry ‘Kordia’ branched very well after Globaryl and TIBA+PBZ treatments too, however, the lateral shoots after treatment with the latter preparation were of low quality. ‘Kordia’ trees after Globaryl treatment were branched in 94% of cases with more than four lateral shoots.

The main objective of this work was to verify the possibility of shortening the time needed to produce nursery trees of plums, in view of the economic profitability in nursery production. To achieve this goal, rootstocks Citation®, Ishtara®, Penta®, Torinel®, Pumiselekt and St. Julien (from Wädenswil) were chip budded in the springtime with ‘Shiro’, ‘Angeleno’®, ‘Black Amber’, SLE2014/1, ‘Fertility’ (Asian type plums) and ‘Stanley’ (European type plum) as a control. At the end of the vegetation period, height (from the grafting position), trunk diameter above the place of budding and the number of shoots was recorded for each tree. The Penta® rootstock was evaluated as the most efficient, while ‘Shiro’ variety was evaluated as the most suitable variety. The best variety/rootstock combination was the combination of ‘Shiro’ on Ishtara® rootstock, where 100% of the budded trees reached an average height of 33.0 ± 3.6 cm. The highest trees of an average of 68.3 ± 4.6 cm were recorded for the combination of SLE2014/1 on Torinel® root-stock.

The most commonly used phytohormone to reduce the impact of drought is 24-epibrassinolide (EBR). In this study, EBR was applied over two years on young rootstocks of peach (B-VA-1) and myrobalan (Vanovice myrobalan) seedlings. Young rootstocks were treated by EBR at different concentrations, IAA and a mixture of EBR with IAA. The best results in seedling height of Vanovice myrobalan in both years had the treatment of 0.05% IAA, 549.69 mm (2016) and 553.77 mm (2017). On the other hand, on the crown root thickness was affected the most in 2016 by treatment of EBR 0.06 ppm (5.5 mm) and in 2017 by EBR 0.01 ppm (7.5mm). At B-VA-1 rootstock, the highest seedlings in 2016 were measured after EBR + IAA treatment (1573.18 mm) and in 2017 after IAA treatment (682.75 mm). The highest thickness of the crown root was recorded in 2016 after EBR and IAA (17.76 mm) and in 2017 after EBR 0.1 ppm (8.08 mm) treatments. At more than half of the treatments the control variant was evaluated as a variant with the least satisfying results. According to the results EBR and IAA are possibly increasing the quality of the rootstocks in conditions of a nursery without an irrigation. info:eu-repo/semantics/openAccess

We used all 167 typhoon warnings issued by the Taiwanese Central Weather Bureau from 1958–2006 to assess the long-term effect of cyclone disturbance on vascular epiphytes. Tracks and eyes of past typhoons were plotted as circles with radii of Beaufort scale 7 and 10, and the frequency of each cohort in 1-km2 grid cells was calculated. The presence of vascular epiphytes in the same grid cells was predicted using species distribution models (SDMs). First, we used herbarium specimens and other sources to compile a comprehensive georeferenced vascular epiphyte database that contained 39084 records in 331 species. Next, we assigned each epiphyte record to a cell in the same 1-km2 grid as above. Finally, we used SDMs (MaXent), based on 30 environmental variables except typhoon frequency, to predict the potential presence of each species in the grid cells. For our analysis we only considered cells east of the central mountain ridge where typhoons hit with full force. After elimination of rare species and species that could not be validated in the SDMs, we were left with 156 epiphyte species in 10725 1-km2 cells. The number of projected species in the cells was 36.5 on average, varying between two and 82 species. Correlation analyses showed that, over time, typhoons led to a decrease in epiphyte richness at Beaufort scale 7 and 10 (Pearson's r = −0.07 and −0.08 respectively). Ferns, orchids, hemiepiphytes and dicotyledons generally showed the same pattern, except hemiepiphytes that showed a positive correlation at B7 (Pearson's r = 0.15). A partial canonical correspondence ordination analysis showed that, independent of temperature- and rainfall-related variables, Beaufort scale 7 and 10 typhoons also had significant influence on the species composition of the vascular epiphyte communities in the landscape. We recommend in situ monitoring of epiphytes over a long period to corroborate the suggestion from this indirect study that typhoons have a long-term effect on the distribution of epiphytes in Taiwan.

In this study, 30 genotypes of genus Pyrus (five European cultivars, 16 Asian cultivars, three rootstocks, four interspecific hybrids, one landrace cultivar from Czech Republic (‘Krvavka’), Pyrus betulaefolia Bunge. and one intergeneric hybrid (Cydomalus)) were tested using AFLP markers. Twelve primer combinations generated a number of 1251 fragments of which 1064 were polymorphic with an average polymorphism of 85.3%. The dendrogram, created by using the UPGMA method, revealed a distinct genetic relationship between European and Asian pear groups. The intergeneric hybrid Cydomalus was separated in the cluster tree from both groups. The level of similarity coefficient between European and Asian pears was 0.75. Despite the fact that Pyrus betulaefolia Bunge was clustered in the European pear group, the average similarity coefficient between the European pear group and Pyrus betulaefolia Bunge (0.7704) was comparable to the similarity coefficient between the Asian pear group and Pyrus betulaefolia Bunge (0.768). Thus, the botanic species Pyrus betulaefolia Bunge can likely be considered as an intermediate genotype between European and Asian pears. The cultivar ‘Talgarskaja Krasavica’ (chance seedling of ‘Forest Beauty’), which pomologically belongs to the European pear group was clustered together with the interspecific hybrid ‘Wu Jiu Xinag’ (‘Ya Li’ × ‘Bartlett’) which on the other hand belongs to the Asian pear group. Thus, due to its position in the dendrogram the cultivar ‘Talgarskaja Krasavica’ could be considered as an interspecific hybrid.

The response of species to climate change is generally studied using ex situ manipulation of microclimate or by modeling species range shifts under simulated climate scenarios. In contrast, a reciprocal transplant experiment was used to investigate the in situ adaptive response of the elevationally widespread epiphytic fern Asplenium antiquum to simulated climate change conditions. Fern spores were collected at three elevations and germinated in a greenhouse. The sporelings (juvenile ferns) were reciprocally transplanted to each collection site. Growth and mortality rates were monitored for 2 years. Wild sporelings were monitored at two sites to assess possible transplant effects. Habitat suitability, indicated by overall growth and survival patterns, declined as elevation increased. Only the highland population showed significant adaptation to the “home” habitat, achieving the highest survival rates. Microclimate data suggest that the presumed genetic adaptation at the highland site occurred mainly in response to drought stress in winter. Based on our previous study on species distribution models, which projected an expansion in the range of A. antiquum under future climate change scenarios, the populations at the upper margins of the species’ elevational range may play an important role during this expansion, given their better adaptation to the shifting marginal conditions. Our study suggests that intraspecific variation should be considered when determining the potential impact of climate change on biodiversity.

Tropical species with narrow elevational ranges may be thermally specialized and vulnerable to global warming. Local studies of distributions along elevational gradients reveal small-scale patterns but do not allow generalizations among geographic regions or taxa. We critically assessed data from 249 studies of species elevational distributions in the American, African, and Asia-Pacific tropics. Of these, 150 had sufficient data quality, sampling intensity, elevational range, and freedom from serious habitat disturbance to permit robust across-study comparisons. We found four main patterns: (1) species classified as elevational specialists (upper- or lower-zone specialists) are relatively more frequent in the American than Asia-Pacific tropics, with African tropics being intermediate; (2) elevational specialists are rare on islands, especially oceanic and smaller continental islands, largely due to a paucity of upper-zone specialists; (3) a relatively high proportion of plants and ectothermic vertebrates (amphibians and reptiles) are upper-zone specialists; and (4) relatively few endothermic vertebrates (birds and mammals) are upper-zone specialists. Understanding these broad-scale trends will help identify taxa and geographic regions vulnerable to global warming and highlight future research priorities.

We present the first checklist of vascular epiphytes in Taiwan, based on herbarium specimens, literature records, and field observations. Epiphyte phytogeography was analyzed using Takhtajan's modified division in floristic regions. We ascertain the presence of 336 species of vascular epiphytes (24 families, 105 genera) in Taiwan. Pteridophytes contribute most species (171 species), followed by orchids (120 species). Epiphytes contribute 8% to Taiwanese floristic diversity and epiphyte endemism is near 21.3%. The extensive mountain system is probably the most effective driver for epiphyte diversification and endemicity in Taiwan. Phytogeographically, Taiwanese epiphytes exhibit equal affinity to the Malesian region, southern China and Indo-China and Eastern Asiatic regions. However, some species have a disjunctive distribution between Taiwan and SW China and/or E Himalaya, presumably related to low habitat similarity with adjacent China and/or the legacy of Late Quaternary climate change. Vascular epiphyte distribution patterns corroborate the phytogeographical separation of the island of Lanyu from the main island of Taiwan along Kanto's Neo-Wallace Line.

Transformation of tropical forests is likely to affect seed-dispersal patterns and influence the composition of epiphytic plant communities in human-altered habitats. We tested this hypothesis by carrying out a comparative study of seed influx, survival and growth of transplanted seedlings of epiphytic bromeliads among isolated trees in six pasture areas, six forest edges and six forest sites in a montane area in Costa Rica. In total, 72 traps trapped 1285 seeds over a 2-mo period in the dry season of 2003. For all four investigated bromeliad genera, Catopsis, Guzmania, Tillandsia and Werauhia, the number of trapped seeds in each habitat followed a pattern similar to the number of fruiting individuals in the vicinity of the traps. Traps in forest edges (30) were 1.9 times more likely to collect seeds than traps at forest interiors (30) and pasture trees (12), the latter showing similar probabilities of catching seeds. After 1 y, survival and growth of 3660 transplanted seedlings from three bromeliad species was significantly higher in forest interiors, providing no explanation for the lower abundance of fruiting adults in that habitat. These results suggest that the successful establishment of epiphytic bromeliads in forest interiors is mainly dispersal-limited. If corroborated, differences in abundance among species at each habitat are likely related to differences in growth rates and reproductive success. Further studies on the growth and mortality of seedlings up to the flowering stage, however, are needed. Netherlands Organization for the Advancement of Tropical Research Museo Nacional de Costa Rica UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

Plant community composition is the combined result of species-specific competitive abilities and the availability of propagules. For epiphytic plants, current hypotheses consider that dispersal-related factors are most important. By controlling seed dispersal constraints, we experimentally examined whether the community composition of epiphytic bromeliads in a tropical premontane area is determined during early phases of seedling recruitment. Also, we tested whether establishment success was related to eco-physiological traits of the species. A total of 7200 seeds were artificially affixed on several host trees in two secondary forest patche sa nd in am ature forest stand. Four bromeliad species with differing physiological characteristics (CAM, C3-CAM, and C3) and habitat preference (secondary vs. primary forest) were selected. We found that differences in seed germination probability among habitats and species were not likely to influence community assembly. After 2 yr, seedling survival and plant development were relatively higher in the early-successional forest. Seedling establishment success was not associated with specific physiological and morphological adaptations or habitat preference of the studied species. Our results were not consistent with the described community composition and rates of population recruitment of the studied species in the same successional habitats. The results support the hypothesis that chance and historic events related to seed dispersal have an important influence on community assembly of epiphytic plants. In addition, differences in growth rates and reproductive turnover among species are expected to influence the relative abundance and recruitment rates in a particular habitat.

Summary The bromeliad Tillandsia eizii is a striking species with large, colorful, and persistent inflorescences that can reach 1m in length. The value of this plant as an ornamental and its importance in cultural and religious activities has led to its overcollection in the wild. Clonal propagation via tissue culture may be a means to repopulate native stands while meeting the demands for this species as an ornamental and ceremonial plant. Adventitious bud proliferation was induced from axenically germinated seedling material. Parameters evaluated were the age of explant material at the time of transfer onto bud-induction medium, the concentration of plant growth regulators, and the period of exposure to induction medium. Light and scanning electron microscopy (SEM) established the origin and development of buds. Twelve-week-old seedling explants rapidly initiated adventitious buds after a 30-d induction period on shoot-initiation medium. Adventitious buds were induced in 40% of the explants placed on media with 2mgl 21 6-benzylaminopurine (BA) (8.88mM) plus 0.1mgl 21 a-naphthaleneacetic acid (NAA) (0.54 mM) with some cultures becoming highly prolific after repeated subculture. Shoots elongated in proliferating cultures, and plants were successfully acclimatized and planted into the greenhouse. The results indicate that tissue culture may be used as a means to propagate this epiphytic bromeliad species, which is being seriously affected by deforestation and habitat destruction. In addition, adventitious bud proliferation can provide a means to propagate superior genotypes.

Predispersal characteristics that affect the reproductive success in plants may influence their colonizing ability. We evaluated this hypothesis in two sympatric epiphytic bromeliads in Costa Rica, Guzmania monostachia and Tillandsia fasciculata, that show contrasting levels of local seedling recruitment. Genets of G. monostachia, the species with higher recruitment, may reach the reproductive stage faster because of a higher growth rate (6 vs. 13 yr). In addition, in established genets, new asexual ramets develop and reproduce annually, whereas in T. fasciculata, the slower offshoot development implies at least 3 yr to disperse a new batch of seeds. A higher and more continuous seed production in G. monostachia is possible because of a shorter time from flowering to seed dispersal (8–9 vs. 16–20 mo), along with the production of more flowers (29 vs. 22) and naturally pollinated fruits per inflorescence (89% vs. 79% fruit set) and more seeds per fruit (321 vs. 240). Both species showed a high occurrence of spontaneous autogamy that matched the highly selfing condition estimated using microsatellite markers. In all, G. monostachia displayed the reproductive traits of a pioneer species. Here, we emphasize the importance of seed availability in determining the population and community structure of epiphytic bromeliads in secondary and mature forests, along with factors affecting dispersal and plant survival. Netherlands Organization for the Advancement of Tropical Research Museo Nacional de Costa Rica UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

The species richness, number of plants, biomass, and species composition of holo- and hemi-epiphytes were recorded in fifty-six 0.04-ha plots, distributed over forest fallows of 2–30 y old and mature forests in lowland Amazonia (Amacayacu National Park, Colombia). A total of 9190 epiphytic plants representing 162 species were recorded on 4277 phorophytes. Seventy species were classified as holo-epiphyte and 85 as hemi-epiphyte. Aroids were most diverse (58 species) and represented 76% of the total recorded biomass. Anemochory was more dominant among holo-epiphytes and zoochory among hemi-epiphytes. The species richness, density and biomass of both holo- and hemi-epiphytes increased significantly from young fallows to old fallows and mature forests. Hemi-epiphytes had greater density and biomass than holo-epiphytes. In canonical ordination, forest age did not relate to the species composition of holo-epiphytes. However, for hemi-epiphytes, the age effect was significant, suggesting that species turnover takes place in the ageing fallows.

We analyzed the differences in species richness, community composition, population structure and within-tree location of epiphytic bromeliads in contiguous secondary and mature forests in a premontane area in Costa Rica. Diversity in the mature forest was highest, and the communities differed in their composition as well as in the recruitment rates of the dominant species. Guzmania monostachia and Catopsis nutans dominated the secondary forests, whereas Tillandsia fasciculata and T. tricolor were more abundant in the mature forest. The secondary forest species showed high rates of seedling recruitment while the opposite was found for the mature forest species. Species presence and abundance among and within habitats did not correlate with their physiological (i.e. CAM vs. C3 photosynthesis) or morphological attributes. The spatial distribution patterns were similar among habitats; bromeliads tended to aggregate on a few relatively large phorophytes. The species shared a similar vertical stratification within habitats, except for the two dominant species in the early and mid-successional stages, although its ecological implication is not clear. With some exceptions, conspecifics of different ages were located on similar substrate types (i.e. stems, primary, secondary, or tertiary branches) within the tree-crowns, which suggests limited within-tree dispersion. Differences in species composition and rates of seedling recruitment among secondary and mature forest may arise from ecophysiological differences among species; however, the combined effect of seed availability and dispersal differences may have a larger influence. Thus, epiphyte community assembly can only be understood when the differences in habitat conditions, the availability of propagules, their dispersal characteristics and requirements for seedling establish ment are known. & 2006 Gesellschaft fu¨r O¨kologie. Published by Elsevier GmbH. All rights reserved. Analizamos las diferencias en la riqueza de especies, la composición de la comunidad, la estructura de la población y la ubicación dentro del árbol de las bromelias epífitas en bosques secundarios y maduros contiguos en un área premontana en Costa Rica. La diversidad en el bosque maduro fue mayor y las comunidades diferían en su composición así como en las tasas de reclutamiento de las especies dominantes. Guzmania monostachia y Catopsis nutans dominaron los bosques secundarios, mientras que Tillandsia fasciculata y T. tricolor fueron más abundantes en el bosque maduro. Las especies de bosque secundario mostraron altas tasas de reclutamiento de plántulas mientras que se encontró lo contrario para las especies de bosque maduro. La presencia y abundancia de especies entre y dentro de los hábitats no se correlacionó con sus atributos fisiológicos (es decir, fotosíntesis CAM vs. C3) o morfológicos. Los patrones de distribución espacial fueron similares entre los hábitats; las bromelias tendieron a agregarse en unos pocos forófitos relativamente grandes. La especie compartió una estratificación vertical similar dentro de los hábitats, a excepción de las dos especies dominantes en las etapas de sucesión temprana y media, aunque su implicación ecológica no está clara. Con algunas excepciones, los congéneres de diferentes edades se ubicaron en tipos de sustrato similares (es decir, tallos, ramas primarias, secundarias o terciarias) dentro de las copas de los árboles, lo que sugiere una dispersión limitada dentro de los árboles. Las diferencias en la composición de especies y las tasas de reclutamiento de plántulas entre bosques secundarios y maduros pueden surgir de diferencias ecofisiológicas entre especies; sin embargo, el efecto combinado de la disponibilidad de semillas y las diferencias de dispersión pueden tener una influencia mayor. Por lo tanto, el ensamblaje de la comunidad de epífitas solo puede entenderse cuando se conocen las diferencias en las condiciones del hábitat, la disponibilidad de propágulos, sus características de dispersión y los requisitos para el establecimiento de plántulas. & 2006 Gesellschaft fu¨r O¨kologie. Publicado por Elsevier GmbH. Reservados todos los derechos. Universidad Nacional, Costa Rica. Escuela de Ciencias Biológicas

The floral phenology, fruit and seed production, and self-compatibility of Werauhia gladioliflora, an epiphytic bromeliad with a wide distribution, were studied in a premontane forest in the Monteverde area in Costa Rica. The species presents the pollination syndrome of chiropterophily, and it is visited by the small bats Hylonycteris underwoodi and Glossophaga commissarisi (Glossophaginae). The population flowering period extended from October to early December (end of rainy season) and seed dispersal occurred from February to April (dry season). Most plants opened a single flower per night, either every day or at one-day intervals during the flowering period. In natural conditions, the average fruit set amounted to almost half of the potential output, but individual fecundity (number of seeds) remained high. Seed number per fruit and germination capacity after artificial selfing and out-crossing treatments did not differ from natural pollination conditions. Werauhia gladioliflora exhibited high levels of autonomous self-pollination and self-compatibility at the individual and population level, characters associated with the epiphytic habitat. These reproductive traits are also associated with early colonizer species, yet life history traits, such as seed dispersal, seedling establishment success, and growth, are likely to have a major role in determining the presence of this species in the successional vegetation patches scattered over the studied premontane area. Netherlands Organization for the Advancement of Tropical Research Museo Nacional de Costa Rica UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

Tillandsia eizii is an epiphytic bromeliad that due to over-collection, habitat destruction, and physiological constraints has declined to near threatened status. This species exhibits high mortality in the wild, and seed are characterized by low percentages of germination. As a means to conserve this species, in vitro culture protocols were developed to enhance seed germination and seedling growth. A sterilization protocol using 70% ethanol for 2 minutes followed by 2.6% NaOCl for 40 minutes disinfested seed and promoted seedling growth. Sucrose incorporated into the culture medium had no effect on germination or growth, while NAA inhibited growth, but not germination. Cultures maintained under a 16-hour photoperiod at 22 °C exhibited greater growth than those grown at 30 °C. Seed that germinated in the dark remained etiolated and failed to develop even after transfer to light conditions. Plants grown in vitro were successfully acclimatized and transferred to the greenhouse. Over 86% survival and rapid growth were obtained with either an all-pine-bark medium, or a mixture of 2 redwood bark: 2 fir bark: 2 potting mix: 1 perlite. This demonstrated that in vitro culture of seed may be used to rapidly produce large numbers of T. eizii, and thus can be used for the conservation and reintroduction of this species.

Information on genetic variation and its distribution in tropical plant populations relies mainly on studies of ground‐rooted species, while genetic information of epiphytic plants is still limited. Particularly, the effect of forest successional condition on genetic diversity and structure of epiphytes is scanty in the literature. We evaluated the genetic variation and spatial genetic structure of the epiphytic bromeliad Guzmania monostachia (Bromeliaceae, Tillandsioideae) in montane secondary forest patches in Costa Rica. The sampling design included plants on the same trees (i.e., populations), populations within forest patches and patches within secondary forest at two different successional stages (early vs. mid‐succession). Six microsatellites revealed low levels of population genetic variation (A = 2.06, AE = 1.61, HE = 0.348), a marked deficiency of heterozygotes (HO = 0.031) and high inbreeding (f = 0.908). Genetic differentiation was negligible among populations within the same forest patch, but moderate (GST = 0.123 ± 0.043) among forest patches. Genetic relatedness between individuals was significantly higher for plants located within the same forest patch and separated by 400 m. An analysis of molecular variance (AMOVA) showed significant genetic variation between forest patches, but non‐significant variation between successional stages. The selfing breeding system and limited seed dispersal capabilities in G. monostachia could explain the observed levels and partitioning of genetic diversity at this geographic scale. However, these results also suggest that forest fragmentation is likely to influence the degree of local genetic structuring of epiphytic plants by limiting gene flow. WOTRO, The Netherlands (Grant W85-34) UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

Each Christmas season, the abundance of terrestrial bryophytes in the Abies-dominated forests of the Sierra Chincua, part of the Monarch Butterfly Biosphere Reserve, attracts moss gatherers. Bryophyte mats are harvested as ornamentals, packed, and sold at the central auction of Mexico City. In 1996, we followed a group of about 10 family members in this activity and documented economic and ecological aspects. During the season they removed in total nearly 50 tons of fresh weight of bryophytes from the forest floor that was sold for approximately $3,500 USD, leaving behind a mosaic of gaps of bare soil in the mossy layer. The average gap size was 0.48 m2 and extraction intensity varied between 0.5 and 4.1% of the total surface area (2.14% on average). In addition, over 11,000 Abies seedlings were unintentionally removed. We are conceive that the Mexican norm for bryophyte harvesting is not in line with current practices and we recommend the inclusion of guidelines for patch size, and that harveste...

The epiphytic vegetation on host trees along an altitudinal transect on the west slope of the Central Cordillera in Colombia was sampled. Bark-type restricted sampling comprised four full-grown forest trees, not necessarily four species, at altitudinal intervals of c. 200 meters from 1000 to 4130 m a.s.l. and included the canopy. Both vascular and non-vascular epiphytes, the latter often more abundant in the montane rain forest, were included in the analyses. Using a method of direct gradient analysis, canonical correspondence analysis, the variation explained by various environmental variables could be discriminated from a great amount of variation that seemed not related to any ecological factor. To a large extent, the randomness in propagule supply appears to determine the floristic composition on branch/trunk segments. The grouping of releves in a phytosociological analysis concurred with a clustering of samples in an ordination diagram of the first two extracted constrained axes. The sample scores on these two axes were strongly correlated with the complex variables ‘altitude’ and ‘height within the host tree’. Specialists and generalists with respect to the two variables were defined based on tolerances provided by the canonical correspondence analysis as was the position of species on the gradients involved. Independently from any of the other variables entered, a relation between the epiphytic vegetation and host species was detected, particularly in the case of Brunellia occidentalis, a fast growing tree species of higher altitude. No relation between chemical characteristics of suspended soil in the Upper Montane Rain forest and its supporting species could be demonstrated.

Flower predation or florivory may alter the sexual expression, floral display, and reduce the reproductive success in plants. In this article, we estimated the effect of florivory on the reproductive success of the epiphytic bromeliad Werauhia gladioliflora during 2001–2003 in a premontane area in Costa Rica. Floral buds of W. gladioliflora are attacked by the wasp Eurytoma werauhia (Eurytomidae), which inhibits flower anthesis. Nearly, a quarter of the sampled population flowers were lost due to wasp infection and it accounted for nearly 70% of the reduction in fruit set. Flowers located on the inflorescence upper segment had a higher attack incidence. In the studied population, florivory has a major role in the reproductive success of W. gladioliflora. Florivory on epiphytic plants is scarcely reported in the literature, but evidence suggests that this phenomenon is more spread in the epiphytic community. Whether florivory in W. gladioliflora is a selective pressure influencing the reproductive success or a localized factor operating at the studied population is a subject requiring additional data. Netherlands Organization for the Advancement of Tropical Research UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

The sampling of epiphytes is fraught with methodological difficulties. We present a protocol to sample and analyse vascular epiphyte richness and abundance in forests of different structure (SVERA). Epiphyte abundance is estimated as biomass by recording the number of plant components in a range of size cohorts. Epiphyte species biomass is estimated on 35 sample-trees, evenly distributed over six trunk diameter-size cohorts (10 trees with dbh > 30 cm). Tree height, dbh and number of forks (diameter > 5 cm) yield a dimensionless estimate of the size of the tree. Epiphyte dry weight and species richness between forests is compared with ANCOVA that controls for tree size. SChao1is used as an estimate of the total number of species at the sites. The relative dependence of the distribution of the epiphyte communities on environmental and spatial variables may be assessed using multivariate analysis and Mantel test. In a case study, we compared epiphyte vegetation of six Mexican oak forests and one Colombian oak forest at similar elevation. We found a strongly significant positive correlation between tree size and epiphyte richness or biomass at all sites. In forests with a higher diversity of host trees, more trees must be sampled. Epiphyte biomass at the Colombian site was lower than in any of the Mexican sites; without correction for tree size no significant differences in terms of epiphyte biomass could be detected. The occurrence of spatial dependence, at both the landscape level and at the tree level, shows that the inclusion of spatial descriptors in SVERA is justified.

For the immediately threatened forests and bromeliads in the highlands of Chiapas, Mexico, we suggest an empirical approach to attain sustainability in the gathering of bromeliads for home decoration. On the basis of theoretical considerations and the results from a pilot study in three forest stands along a disturbance gradient at La Florecilla, we propose that harvesting should be limited to populations (1) that have a density no less than 9000 large rosettes/ha, (2) that are evenly distributed in space, and (3) that grow in the lower stratum of the forest, thus having little effect on their reproductive capacity. In a second study at La Florecilla we used a plotless point-centred quarter method to estimate the population density and homogeneity in spatial distribution of all species of bromeliads in the structurally heterogeneous forest. We found one species, Tillandsia vicentina, that met the prerequisites, having both a satisfactory average population density of ca. 24,000 large (>20 cm) rosettes/ha on oaks and a spatially even distribution. We estimate that an annual harvest of 112,000 rosettes of T. vicentina from the lower stratum of the 160 ha forest at La Florecilla can be maintained, in a 4-year rotation cycle. The implementation of a monitoring program should be included in any management plan.

Many bromeliad species indigenous to the rain forests of Central and South America are threatened because of over-collection and habitat destruction. Studies were conducted to develop propagation protocols for Tillandsia eizii, a rare ornamental bromeliad of ceremonial significance to the Highland Maya communities in Chiapas, Mexico. We anticipate using in vitro propagation for the conservation of this species with the potential of utilizing bromeliads as an alternative and sustainable forest resource. Protocols were developed for the sterilization and germination of axenic seed. Seedling growth in vitro was assessed and outplanting studies were conducted. Media were evaluated to promote adventitious bud production in experiments using the plant growth regulators naphthaleneacetic acid and benzylaminopurine. Pulse time and duration, as well as the stage of seed development, had a marked effect on bud production. The effects of various potting media on plant growth and survival were assessed. A pure pine bark medium elicited over 95 percent survival. Plants exhibited a “tank-like” morphology characteristic of plants in the wild.

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015. The collation of biodiversity datasets with broad taxonomic and biogeographic extents is necessary to understand historical declines and to project - and hopefully avert - future declines. We describe a newly collated database of more than 1.6 million biodiversity measurements from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. © 2014 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.