Vegetation influence on ectomycorrhizal inoculum Available to sub-arctic willow (Salix lapponum L.) planted in an upland Site

Summary

Restoration of scrub and woodland in deforested upland sites is an important conservation activity. However, little is known about the mycorrhizal colonisation potential of upland soils or the factors that influence the distribution of mycorrhizal inoculum. We investigated the effect of existing vegetation on mycorrhizal colonisation potential for a sub-arctic willow (Salix lapponum) by planting uninoculated cuttings into plotsrepresenting two upland habitats with either grassand herbs (‘grass’) or Vaccinium myrtillus (‘vaccinium’) and assessing mycorrhizal colonisation after 14 months using morphological and molecular techniques. From 40 willow cuttings (20 in each habitat), DNA sequences of rive ectomycorrhizal (EcM) fungal taxa were recovered: Laccaria proxima, Thelephora terrestris, Hebeloma sp., ‘Thelephoraceae sp.’ and ‘Pezizales sp.’. Cuttings in the ‘grass’ habitat were dominated by Laccaria proxima and ‘Pezizales sp.’ and in the ‘vaccinium’ habitat by Thelephora terrestris which was absent from the ‘grass’ habitat. There were no significant differences between habitats in frequency of EcM inoculum (overall percentage of cuttings colonised = 70%) or colonisation potential (overall mean percentage of root tips colonised per cutting = 20 %). These data suggest that the mycorrhizal colonisation potential and diversity of fungi available to willow in these upland soils are low and planted willow may benefit from inoculum enhancement.     

Sediments,not plants,offer the preferred refuge for Daphnia against fish predation in Mediterranean shallow lakes: an experimental demonstration

1. Different behavioural responses of planktonic animals to their main predators, fish, have been reported from shallow lakes. In north temperate lakes, large‐bodied zooplankton may seek refuge from predation among macrophytes, whereas in subtropical lakes, avoidance of macrophytes has been observed. The prevalent behaviour probably depends on the characteristics of the fish community, which in Mediterranean lakes is typically dispersed in both the open water zone and in the littoral, as in temperate lakes, and is dominated by small size classes, as in subtropical lakes. 2. We performed ‘habitat choice’ experiments to test the response of Daphnia magna to predation cues at both the horizontal and vertical level by mimicking a ‘shallow littoral’ zone with plants and a ‘deeper pelagic’ zone with sediments. 3. Initial separate response experiments showed that natural plants, artificial plants and predation cues all repelled D. magna in the absence of other stimuli, while sediments alone did not trigger any significant response by D. magna. 4. The habitat choice experiments showed that, in the presence of predation cues and absence of plants, Daphnia moved towards areas with sediment. In the presence of both plants and sediments, Daphnia moved away from the plants towards the sediments under both shallow and deep water treatment conditions. 5. Based on these results, we suggest that Daphnia in Mediterranean shallow lakes avoid submerged macrophytes and instead prefer to hide near the sediment when exposed to predation risk, as also observed in subtropical shallow lakes. This pattern is not likely to change with water level alterations, a common feature of lakes in the region, even if the effectiveness of the refuge may be reduced.     

Theoretical habitat templets, species traits, and species richness: Plecoptera and Ephemeroptera in the Upper Rhône River and its floodplain

• 1 Ephemeroptera and Plecoptera in two sites of the Upper Rhône River (France) were examined using multivariate analyses to determine: (i) relationships among seventeen species traits; (ii) habitat utilization of the fifty-five species present; (iii) the relationship between species traits and habitat utilization; (iv) trends of species traits and species richness in a framework of spatial and temporal habitat variability.
• 2 The species traits having the highest correlation ratios correspond to reproduction or life cycle, behavioural, and morphological characteristics. According to their traits, species of Baetidae, Caenidae, and Leptophlebiidae (Ephemeroptera) are opposite species of Perlidae and Perlodidae (Plecoptera).
• 3 The distribution of species in thirteen habitat types of the Upper Rhône River floodplain demonstrates a transverse gradient from the main channel to the oxbow lakes. Plecoptera are restricted to the different main channel habitats; in contrast, Ephemeroptera families have a broader distribution with Baetidae and Leptophlebiidae occurring in most floodplain habitats.
• 4 Plecoptera exhibit a significant relationship between species traits and habitat utilization but no relationship is evident for Ephemeroptera. Baetidae use many habitat types and have diverse species traits; in contrast, Leptophlebiidae, Heptageniidae, and Caenidae use many habitat types but each family has a rather uniform set of traits.
• 5 Trends in species traits were significantly related to both the spatial and temporal variability of habitats. Considering only temporal variability, the distribution of species trait modalities (= categories) corresponded well to predictions on trends in the river habitat templet for ‘minimum age at reproduction’ and ‘potential longevity’, and in general for ‘descendants per reproductive cycle’, ‘reproductive cycles per year’, ‘potential size’, and ‘body flexibility’ trends in six other traits did not match predictions.
• 6 No trends in species richness were evident in spatial–temporal framework of habitat variability.

     

Roditis Leaf Discoloration - A New Virus Disease of Grapevine: Symptomatology and Transmission to Indicator Plants

The symptoms and some characteristics of an unreported disease of grapevine, which was observed during the last years on the cv. ‘Roditis’ in central Greece, are described. The disease is transmissible to V. vinifera‘Mission’ and to some herbaceous test plants. The constant association of a virus to naturally infected plants cv. ‘Roditis’ and chip-budding infected indicator plants cv. ‘Mission’ supports the evidence that the disease is caused by a virus.     

The role of demography,intra‐species variation,and species distribution models in species' projections under climate change

Organisms are projected to shift their distribution ranges under climate change. The typical way to assess range shifts is by species distribution models (SDMs), which predict species’ responses to climate based solely on projected climatic suitability. However, life history traits can impact species’ responses to shifting habitat suitability. Additionally, it remains unclear if differences in vital rates across populations within a species can offset or exacerbate the effects of predicted changes in climatic suitability on population viability. In order to obtain a fuller understanding of the response of one species to projected climatic changes, we coupled demographic processes with predicted changes in suitable habitat for the monocarpic thistle Carlina vulgaris across northern Europe. We first developed a life history model with species‐specific average fecundity and survival rates and linked it to a SDM that predicted changes in habitat suitability through time with changes in climatic variables. We then varied the demographic parameters based upon observed vital rates of local populations from a translocation experiment. Despite the fact that the SDM alone predicted C. vulgaris to be a climate ‘winner’ overall, coupling the model with changes in demography and small‐scale habitat suitability resulted in a matrix of stable, declining, and increasing patches. For populations predicted to experience declines or increases in abundance due to changes in habitat suitability, altered fecundity and survival rates can reverse projected population trends.     

Dispersal behaviour of individuals in metapopulations of two British butterflies

Dispersal patterns are important in metapopulation ecology because they affect the dynamics and survival of populations. However, because little empirical information exists on dispersal behaviour of individuals, theoretical models usually assume random dispersal. Recent empirical evidence, by contrast, suggests that the butterfly Maniola jurtina uses a non‐random, systematic dispersal strategy, can detect and orient towards habitat from distances of 100–150 m, and prefers a familiar habitat patch over a non‐familiar one (‘homing behaviour’). The present study (1) investigated whether these results generalise to another butterfly species, Pyronia tithonus; and (2) examined the cause of the observed ‘homing behaviour’ in M. jurtina. P. tithonus used a similar non‐random, systematic dispersal strategy to M. jurtina, had a similar perceptual range for habitat detection and preferred a familiar habitat patch over a non‐familiar one. The ‘homing behaviour’ of M. jurtina was found to be context‐dependent: individual M. jurtina translocated within habitat did not return towards their capture point, whereas individuals translocated similar distances out of habitat did return to their ‘home’ patch. We conclude that butterfly ‘homing behaviour’ is not based on an inherent preference for a familiar location, but that familiarity with an area facilitates the recognition of suitable habitat, towards which individuals orient if they find themselves in unsuitable habitat. Contrary to conventional wisdom, we suggest that frequent, short ‘excursions’ over habitat patch boundaries are evolutionarily advantageous to individuals, because increased familiarity with the surrounding environment is likely to increase the ability of a straying animal to return to its natural habitat, and to reduce the rate of mortality experienced by individuals attempting to disperse between habitat patches. We discuss the implications of the non‐random dispersal for existing metapopulation models, including models of the evolution of dispersal rates.     

MORE ON SHEPPARD'S BIRD WORK IN THE PORTUGUESE VUMBA

Habitat selection by Hyliota australis in southern Africa is assessed using newly collated habitat and hyliota distribution data. This is done hierarchically, assessing its occurrence in different types of moist-dystrophic savanna, different types of stands of miombo, as well as in different types of landscape mosaics in which miombo occurs. The considerable variation in miombo ecosystem composition, physiognomy and functioning influence its occurrence at all scales. While available data over such a vast area have proved useful—for example, in identifying the importance of ecosystems dominated by Brachystegia spiciformis-there is a dire shortage of data describing the diversity of miombo ecosystems, which hinders a fuller understanding. There is a need for: (1) a hierarchical classification and (2) relatively fine-resolution mapping of the ecosystems of south-central Africa - together ‘an ecosystem inventory’. This is now urgent given the escalating losses of woody cover. All species that rely on undisturbed, ‘old-growth’ canopy miombo are at risk in southern Africa because of high rates of habitat loss on the Mashonaland Plateau, <1% of which occurs in the conservation estate.     

COLCHIPLOIDY AND HISTOLOGICAL IMBALANCE IN TRIPLOID APPLE AND PEAR

Colchicine treatment of the triploid apple varieties ‘Paragon’ and ‘Stayman’ resulted in 6–3–3 and 3–6–6 chimeras, and 6–3–3 chimera in ‘Baldwin.’ Treatment of a triploid pear selection ‘U.S. 44–3–1’ resulted in totally 6x as well as 6–3–3 and 3–6–6 chimeras. As triploid plants are not suitable for breeding, sexually hexaploid forms (totally 6x or chimeral 3–6–6) of high-quality triploid apples and pears may become very useful as breeding material. The primary purpose of treating the ‘Stayman’ apple was to obtain a 6–3–3 chimera to find out if large cells in the epidermis would reduce or eliminate the severe cracking of fruit of this variety which occurs in some seasons. Chimeral forms in the other plants were to serve as material for comparison with the ‘Stayman’ variety. Observations on the fruit-cracking problem will have to wait until the chimeral plants fruit. Hexaploid tissue in chimeral shoots of all affected plants has grown more slowly than triploid tissue, causing various degrees of malformation of the leaves. Similar reduction in growth due to restricted ploidization in 4–2–2 or 2–4–4 chimeras has not resulted in many other plants, including apples and pears, but was reported in an 8–4–4 chimera in cranberry. Slower growth of 6x tissue in the apple and pear may be attributed to the presence of multiple homologous genes in the duplicated chromosome forms of these particular triploid plants.     

The effects of feeding by the rice water weevil, Lissorhoptrus oryzophilus Kuschel, on the growth and yield components of rice, Oryza sativa

Abstract 1 The effects of feeding by larvae of the rice water weevil, Lissorhoptrus oryzophilus Kuschel, on the growth and yield components of rice, Oryza sativa, were evaluated using four varieties of rice, ‘Cocodrie’, ‘Cypress’, ‘Bengal’ and ‘XP1003’, over 2 years. 2 Both adults and larvae of L. oryzophilus feed on rice plants, but it is feeding by the larval stage that causes economic losses. Feeding by L. oryzophilus larvae resulted in extensive damage to root systems. Pruning of root systems resulted in a decrease in tiller number and shoot biomass of rice plants in the vegetative stage of growth. 3 Yield losses were due to a combination of decreases in panicle densities, numbers of grains per panicle, and grain weights. Decreases in panicle densities were a direct result of the reductions in tiller numbers. Reductions in numbers of grains per panicle and grain weights probably resulted from decreases in shoot biomass. 4 Injury by rice water weevil larvae is chronic. The tillering stage of rice suffered the majority of weevil damage, but the growth effects were not manifested until later.     

Vole–vegetation interactions in an experimental, enemy free taiga floor system

Vole–vegetation interactions in a predation‐free taiga environment of northern Fennoscandia were studied by transferring vegetation from natural Microtus habitats into a greenhouse, where three habitat islands of about 30 m² were created. The ‘islands’ were subjected to simulated summer conditions and a paired female field vole, Microtusagrestis, was introduced to each ‘island’. The development of the female and her young was followed by recurrent live trapping. The development of the vegetation was followed by recurrent marking and censusing of plant shoots at intervals of five days. In the next growing season, two ‘islands’ were subjected to a new grazing treatment to study the impacts of repeated grazing on the vegetation and on the growth and reproduction of voles. Plant biomasses were harvested at the end of each trial. In all trials, the biomasses of graminoids and non‐toxic herbs other than ferns, fireweeds and rosaceous plants were profoundly decimated. Even the biomass of a toxic herb Aconitum lycoctonum decreased largely at pace with the palatable herbs. The least preferred plant categories maintained their biomasses at control levels. Their neutral collective response was created by opposite species‐level trends. Species typical for moist and nutrient‐rich forests suffered from vole grazing, whereas the biomass of species adapted to disturbed habitats increased. In spite of the dramatic changes in the vegetation, the introduced female voles survived throughout the trials and reproduced normally. The young of their first litters survived well and reached the final weights typical for individuals starting to winter as immatures. We conclude that most of the plant biomass found on productive boreal forest floors is potential food for field voles and remains palatable for them even when subjected to recurrent, severe grazing. If nothing else than summer resources were limiting the growth of the field vole populations, the plants currently dominating moist and nutrient‐rich taiga floors could not survive in this habitat.     

Brown trout (Salmo trutta,Linnaeus, 1758) spawning habitat improvement in the Ebro River Basin (eastern Spain)

Limestone streams in Spain are subject to calcium carbonate precipitation processes, which make the substrate very cohesive. Many populations of brown trout (Salmo trutta, Linnaeus, 1758) in those rivers show reduced production due to unsuitable spawning habitats. This study presents data on S. trutta spawning habitat improvement in the Guadalope River Basin during 2011. The main objectives of this study were to (i) modify the substrate in order to make it easier for S. trutta females to dig when spawning, (ii) test the effect of the gravel quality improvement on the habitat, (iii) analyse the effect of habitat improvement on S. trutta recruitment, and (iv) monitor habitat improvement effectiveness in the long term. Three manual measures were adopted to make the gravel suitable for S. trutta breeding: the separation of the embedded gravel using an iron bar by hitting it with a mace‐hammer (‘substrate breaking’), the spreading out of the gravel loosened by the previous action with a rake (‘raking up’), and thirdly the elimination of fine sediment depositions (‘substrate cleaning’). Results of the first year of monitoring (2012) in improved and control areas were compared. Methodology effectiveness assessment requires monitoring over a longer period, but the data from the first year after habitat improvement provide encouraging results, mainly dealing with changes in spawning habitat parameters and an increase in the S. trutta age‐0 class in the improved areas.     

Notes On Strand Plants. II. Cakile Maritima,Scop

Summary

Buxbaumia aphylla is a rare and enigmatic moss in Britain where it is found regularly and in sizeable populations only on colliery debris (‘bings’) in central Scotland. Its habitat preferences and ecology are described from a range of sites. It has persisted in quantity in several localities for over 20 years, but in other apparently suitable sites it is absent. Destruction and landscaping of bings are seen as the major threat to the species in Scotland.     

The impacts of beavers Castor spp. on biodiversity and the ecological basis for their reintroduction to Scotland,UK

相似文献   

Frugivore behaviour determines plant distribution: a spatially‐explicit analysis of a plant‐disperser interaction

The spatial distribution of plants (and other primarily sessile organisms) depends on the interplay between their ecological requirements and the spatial template set before, during, and after the dispersal process. In the case of animal‐dispersed plants, the spatial characteristics of animal behaviour during the seed dispersal process are likely to leave a lasting imprint on plant distribution. Here, we hypothesize that the activity patterns of the frugivorous lizard Podarcis lilfordi directly influence the spatial distribution of the fleshy‐fruited shrub Daphne rodriguezii. To evaluate this hypothesis, we first analysed lizard activity, following radio‐tracked lizards during the plant's fruiting period, and identified its main determinants at several spatial scales of habitat aggregation (from 12.5 to 150 m). We hypothesised that lizard activity depends on differential habitat features explaining its territory use plus habitat preferences associated with each movement bout. In a second step, the most important determinants of lizard activity plus the variables describing habitat structure were used to predict the presence of adult and juvenile plants. Predictability of lizard activity (based on AUC and Pearson regression coefficients) was higher at broad spatial‐scales of habitat aggregation (75 m). The two best predictors of lizard activity were the habitat features of and the distance to the core area (defined as the area enclosing the 0.50 cumulative probability of lizard locations). Plant presence was best predicted by models based on a combination of lizard activity and habitat features at local spatial scales (1.5 m). Best models included habitat features and lizard activity for adult plants, and local‐scale habitat features, the proximity of adult plants and lizard activity for juveniles. In both cases, most plants (50–60%) were located at ‘optimal sites’ (both favourable for lizards and with adequate habitat features), whereas a small fraction of them (3–10%) were located at dispersal‐limited sites (i.e. with adequate habitat features but suboptimal for lizards). Our results thus suggest that the interplay between lizard activity and local habitat features determines the spatial patterns of juvenile‐plant presence and leaves a lasting signature on adult‐plant distribution.     

Molecular detection and identification of phytoplasmas associated with Catharanthus roseus,Pinus eldarica,and Petunia hybrida in southeastern Iran's urban green spaces

Given the potential for urban green spaces to provide fresh and healthy environments for humans, exploring the issues that threaten plants in these places is crucial. Phytoplasma-related symptoms were encountered on some plants in urban green spaces in the province of Kerman, southeastern Iran, between 2017 and 2019. Affected periwinkles and petunias exhibited phytoplasma disease symptoms, including virescence, phyllody, and witches'-broom. However, ball or disc-like shoot proliferation symptoms were noticed on the trunks and branches of pine trees. PCR was performed with phytoplasma-detecting universal primers, targetting and amplifying the 16S rRNA gene, and determining whether phytoplasmas are implicated in the symptomatic plants. The infection of the symptomatic plants was confirmed using nested-PCR amplification of expected DNA sizes for phytoplasmas. No product, however, was amplified from sampled symptomless plants. The sequencing of nested-PCR products was performed to obtain sequences encasing the standard F2nR2 fragments. The resulted sequences were submitted to iPhyClassifier, the universal phytoplasma classification platform, for the taxonomic assignment of the found phytoplasmas compared with previously identified ‘Candidatus Phytoplasma’ species, groups, and subgroups. The results revealed that phytoplasma strains related to the species ‘Ca. P. trifolii’ (16SrVI-A subgroup) infect periwinkles and pines. However, strains from the species ‘Ca. P. aurantifolia’ (16SrII-D subgroup) and ‘Ca. P. phoenicium’ (16SrIX-C subgroup) were found in petunias and periwinkles, respectively. To the best of our knowledge, phytoplasmas from the 16SrVI-A and 16SrII-D subgroups are the first reported to infect these plants in Kerman province, while a related strain from the subgroup 16SrIX-C is the first recorded to infect periwinkles in Iran and the second in the world.     

ECOTYPIC DIVERGENCE IN ALPINE POLEMONIUM VISCOSUM: GENETIC STRUCTURE,QUANTITATIVE VARIATION,AND LOCAL ADAPTATION

Polemonium viscosum has a continuous distribution from 3,500 m in the krummholz to 4,025 m on the summit ridges of Pennsylvania Mountain, Colorado. Seeds produced by plants at opposite ends of this cline, 1.5 km apart, differed significantly at allozyme loci in two consecutive breeding seasons. Mean multilocus F_st values for both years (0.015 and 0.069) were significantly different from zero, indicating restricted gene exchange between subpopulations. Average allele frequencies at two individual loci also differed significantly between families comprising krummholz and summit subpopulations. Progeny of plants growing on the summit had higher leaf production rates, more densely packed leaflets, and lower resistance to aphids than progeny of plants growing in the krummholz site, when tested under greenhouse conditions. These differences probably reflect the restricted opportunities for growth and severe exposure at high elevations, and the increased risk from herbivores near timberline. The two subpopulations did not differ in leaf length (stature), leaf width, or pubescence. Reciprocal transplanting of seedlings between krummholz and summit sites confirmed that the differences were adaptive, since progeny from each subpopulation performed significantly better in their parent's habitat. Coordinated studies of genetic structure, quantitative variation, and local adaptation across the elevational range of P. viscosum provide a comprehensive view of ecotypic divergence in this widespread alpine plant.     

Use of Grafting and Calcium Cyanamide as Alternatives to Methyl Bromide Soil Fumigation and their Effects on Growth, Yield, Quality and Fusarium Wilt Control in Melon

Grafting melon (Cucumis melo L.) seedlings on to the Fusarium oxysporum f. sp. melonis (Fom) commercial resistant squash rootstocks ‘Mamouth’ and ‘Nun 9075 RT’ and soil sterilization with calcium cyanamide (CaCN₂, Perlka) were tested in 2001 and 2002 as alternatives to methyl bromide (MB) soil fumigation. Ungrafted seedlings of the F₁ melon hybrid ‘Galia’ were cultivated: (i) in soil sterilized by MB and then artificially infested with Fom (this served as a control), (ii) in soil artificially infested with Fom and then sterilized by MB, (iii) in soil artificially infested with Fom and then sterilized with CaCN₂ (Perlka), grafted seedlings on the commercial rootstocks, (iv) ‘Mamouth’ and (v) ‘Nun 9075 RT’ were cultivated in soil sterilized with MB and then artificially infested with Fom. The grafted plants on ‘Mamouth’ and ‘Nun 9075 RT’ and plants in the Perlka treatment (2001) developed mild symptoms, as indicated by the significantly lower leaf symptom index (LSI; average values 1.06, 1.08 and 1.07) and disease index (DI; average values 1.60, 1.25 and 2.33), respectively, when compared with the controls (average values of LSI = 2.65 and DI = 5.06). Plants grafted on ‘Mamouth’ and ‘Nun 9075 RT’ and plants in the Perlka treatment (2001) were more vigorous than the controls as assessed on plant height, stem diameter and root biomass. When compared with the controls, this resulted in an increased (over years) early production (326.3, 265.8 and 489.1%) and late production (371.0, 357.0 and 404.2%). Fruit size was also larger in early production (29.2, 50.9 and 32.3) and late production (4.3, 15.2 and 26.0). The total soluble solids (^oBrix) increased (over years) in early production (27.4, 39.6 and 47.9) and late production (7.59, 10.07 and 5.6) when compared with the controls. Thus, grafting on resistant squash rootstocks ‘Mamouth’ and ‘Nun 9075 RT’ and soil sterilization with Perlka had positive effects on growth, production and fusarium wilt control in melon.     

Time,space and ecology: why some clades have more species than others

Aim We seek biotic and abiotic explanations for differences in lineage sizes of Afromontane sedges (Cyperaceae, Carex) and buttercups (Ranunculaceae, Ranunculus). Location Mountains of sub‐Saharan Africa and Madagascar. Methods We investigated differences in the species richness and diversification rates of 18 lineages of the pan‐temperate plant groups Carex and Ranunculus, established by long‐distance dispersal on African sky islands. We built generalized linear models to test the individual and the cumulative power of biotic and abiotic factors for predicting variation in the size of lineages. Tested variables were: ages of the lineages, their geographic distributions, number of mountain systems occupied, isolation/distance from ancestral areas, elevation range, number of vegetation zones and habitat types in which lineages are found, light requirement and water availability for each lineage, and the sum of the habitat factors, representing habitat heterogeneity. Habitat conservatism was measured by the overlap in habitats among the species within each lineage. Diversification rate changes were investigated using ‘laser’ in R. Results The number of Carex and Ranunculus lineages on the African mountains accumulated gradually through time. The size of these lineages could best be explained by a model combining age and distribution together with a measure of environmental heterogeneity (either elevation and water availability or habitat heterogeneity). Extensive overlap in environmental characteristics and distribution ranges among the species indicates a relatively high degree of conservatism of these characters. Main conclusions Lineages that are species‐rich are those that have the ability and time to occupy many mountain regions and a wide range of habitats. If allopatric or ecological speciation plays a role, then secondary dispersal and/or niche expansion soon obscures the patterns that may have existed at the point of speciation.     

Cycad propagation by rural nurseries in Mexico as an alternative conservation strategy: 20 years on

Propagation of the cycad Dioon edule aimed at sustainable management in the state of Veracruz, Mexico has been ongoing since 1990 under the supervision of staff at Francisco Javier Botanic Garden, with the principal objectives of addressing illegal trafficking and habitat destruction. Plant sales have been limited. Nevertheless these, along with the sale of other managed forest products, have given the cycad producers and other villagers enough incentive to conserve 80 hectares of cycad habitat and to discourage illegal collecting. This model was taken up by four similar nurseries in the buffer zones of two biosphere reserves in Chiapas for the propagation of four additional cycad species and two endangered Chamaedorea palms. A further biosphere reserve in Puebla hosts a similar nursery for the critically endangered D. caputoi. Here the producers are paid through the Reserve authority for cultivation and reintroduction of the cycad. All species were studied at the population level prior to and during nursery establishment. Cultivation knowledge has been passed on to the farmers as well as limited help in marketing. Seedling reintroduction experiments have been carried out but further demographic studies of D. edule and C. mirandae have given reason to re-think reintroduction strategies. There is great potential for these nurseries to act as shelter for rescued plants during civil engineering projects. The marketing problem is still an issue and has been approached by the involvement of conservation authorities in Chiapas to assist the producers with permit paperwork and to seek markets. This experience is an important example of botanic garden extension to rural communities in Mexico that covers several articles of the Convention on Biological Diversity.