Tree Reproduction Research Articles

Leaf phenology correlates with fruit production in European beech (Fagus sylvatica) and in temperate oaks (Quercus robur and Quercus petraea)

Phenology and fruit production are sensitive to climate. Variation of leaf phenology alters canopy duration (an indicator of growing season length), which in turn affects forest ecosystem functioning and tree productivity. However, the influence of canopy duration on tree reproduction is poorly explored. In this study, we investigated if and to what extent the canopy duration influences fruit production in three major European deciduous trees: European beech (Fagus sylvatica) and two temperate oaks (Quercus robur and Quercus petraea). We used a long-term (11 years) monitoring dataset from 50 populations. In addition to the widely reported main effect of previous summer temperature on fruit production in European beech, we detected a nonlinear relationship between current canopy duration and fruit production. For beech, intermediate canopy duration is associated with highest fruit production. In oaks, fruit production was positively correlated with spring temperature and current canopy duration. Total variance explained by our models is 45% and 13%, for beech and oaks, respectively. These results suggest contrasting effects of expected increase in canopy duration on fruit production: nonlinear in European beech and positive linear in oaks.

Effects of landscape disturbance on seed germination of Enterolobium contortisiliquum (Fabaceae) in Brazilian seasonally tropical dry forest: Are seeds a sensitive biomarker of environmental stress?

Habitat disturbance of native forests is currently the major threat to biodiversity conservation. Plant species can be negatively affected as a result of landscape conversion; thus, it is essential to detect the potential effects of environmental stress on plant performance using reliable bioindicators of quick, cheap diagnosis. Fluctuating asymmetry (FA) describes the degree of the random differences in shape and size among two sides of a bilateral trait of the organisms and reflects the developmental instability of an organism, so we can use it to predict the effects on plant fitness. We evaluated the land-use change stress on seed FA levels, seed germination, and the subsequent seedling development of seed produced by trees that occur in an anthropized and a preserved area of seasonally tropical dry forests (STDF) in Brazil. We sampled 10 ten reproductive trees of Enterolobium contortisiliquum of each landscape condition, and then, 100 seeds per each tree were collected. Additionally, 50 seeds were randomly selected for each tree to determine plant fitness. Despite, we found no true FA in the community, the anthropized area had a lower seed nutritional quality and percentage of germination, and higher germination time of seeds produced than in preserved areas. The dry weight of the aerial part of seedlings did not differ between areas. However, root dry weight and total dry weight were higher in seedlings developed from seeds of anthropized than in preserved areas. Our findings show that seeds of E. contortisiliquum are not a sensitive biomarker to detect full stress conditions of habitat disturbance. However, we demonstrate that habitat disturbance negatively affects plant fitness, decreasing germination percentage, and nutritional quality, and increasing germination time. This fact has potential consequences on recruitment, establishment and survival of E. contortisiliquum in regenerating areas of STDF’s in Brazil.

Passerine birds supporting cross pollination in Erythrina stricta Roxb.

Erythina stricta is an ecologically important tree species in the rainforests of India and its nectar within the flowers contributes to birds’ diet and survival. Reports on the pollination of this species have not been published so far. We therefore explore the reproductive system of this tree species which has great significance to its ecosystem. Birds have an important role in the reproduction of trees through pollination particularly in tropical areas where reproductive success mostly depends on animal pollinator interactions. Study of visitation and nectar feeding behaviour of birds along with breeding system assessment of Erythina stricta. Birds visiting and foraging behaviour was observed during Erythrina stricta flowering season in an indian tropical rainforest. Reproductive system was assessed through controlled pollination experiments. Thirteen bird species were recorded visiting and foraging nectar from the flowers of Erythrina stricta. The maximum numbers of visits recorded were from the Red-vented Bulbul (Pycnonotus cafer, Pycnonotidae). The nectar feeding birds were, either (i) potential pollinator with long bills (e.g. Pycnonotus spp., Chloropsis aurifrons, and Dicrurus spp.) or (ii) nectar robbers with comparatively shorter bills (e.g. Zosterops palpebrosa, Stachyris ruficeps, Macronous gularis, Heterophasia glaciris). Controlled pollination experiments revealed high degree of cross pollination (xenogamy) and self-incompatibility in E. stricta. Birds were more frequent in early mornings and their foraging activity was also observed during evening hours; the frequency however, declined with respect to nectar availability. Long corolla tubes of E. stricta could restrict access to nectar collecting bees.

Passerine birds supporting cross pollination in Erythrina stricta Roxb.

Erythina stricta is an ecologically important tree species in the rainforests of India and its nectar within the flowers contributes to birds’ diet and survival. Reports on the pollination of this species have not been published so far. We therefore explore the reproductive system of this tree species which has great significance to its ecosystem. Birds have an important role in the reproduction of trees through pollination particularly in tropical areas where reproductive success mostly depends on animal pollinator interactions. Study of visitation and nectar feeding behaviour of birds along with breeding system assessment of Erythina stricta. Birds visiting and foraging behaviour was observed during Erythrina stricta flowering season in an indian tropical rainforest. Reproductive system was assessed through controlled pollination experiments. Thirteen bird species were recorded visiting and foraging nectar from the flowers of Erythrina stricta. The maximum numbers of visits recorded were from the Red-vented Bulbul (Pycnonotus cafer, Pycnonotidae). The nectar feeding birds were, either (i) potential pollinator with long bills (e.g. Pycnonotus spp., Chloropsis aurifrons, and Dicrurus spp.) or (ii) nectar robbers with comparatively shorter bills (e.g. Zosterops palpebrosa, Stachyris ruficeps, Macronous gularis, Heterophasia glaciris). Controlled pollination experiments revealed high degree of cross pollination (xenogamy) and self-incompatibility in E. stricta. Birds were more frequent in early mornings and their foraging activity was also observed during evening hours; the frequency however, declined with respect to nectar availability. Long corolla tubes of E. stricta could restrict access to nectar collecting bees.

Propagation of fungi in the soils: A case study of scientific experimental fields of forestry of Tashkent region

The sphere of forestry in our republic is developing in the current years. For the purpose of landscaping the territory of our country, reproduction and cultivation of virginia firs, abina firs, pine species, cypress trees, eastern biota, western camel, spruce and other deciduous trees from coniferous trees is widely established. These ornamental trees differ from other ornamental trees and shrubs in their heat–cold, drought resistance. Different landscapes and forest trees are initially planted in germination plants and seedlings from their seeds. In Uzbekistan, diseases of decorative and forest trees, especially their diseases in the germination period, have almost not been studied. The fact that many different diseases are encountered in landscape trees in recent years is known from different sources. The article provides information on the influence of the seasons on the spread of fungi that have appeared on the soil of some plantations and seedlings in Tashkent region.

Climate Change Strengthens Selection for Mast Seeding in European Beech

Climate change is altering patterns of seed production worldwide [1-4], but the potential for evolutionary responses to these changes is poorly understood. Masting (synchronous, annually variable seed production by plant populations) is selectively beneficial through economies of scale that decrease the cost of reproduction per surviving offspring [5-7]. Masting is particularly widespread in temperate trees [8, 9] impacting food webs, macronutrient cycling, carbon storage, and human disease risk [10-12], so understanding its response to climate change is important. Here, we analyze inter-individual variability in plant reproductive patterns and two economies of scale-predator satiation and pollination efficiency-and document how natural selection acting upon them favors masting. Four decades of observations for European beech (Fagus sylvatica) show that predator satiation and pollination efficiency select for individuals with higher inter-annual variability of reproduction and higher reproductive synchrony between individuals. This result confirms the long-standing theory that masting, a population-level phenomenon, is generated by selection on individuals. Furthermore, recent climate-driven increases in mean seed production have increased selection pressure from seed predators but not from pollination efficiency. Natural selection is thus acting to restore the fitness benefits of masting, which have previously decreased under a warming climate [13]. However, selection will likely take far longer (centuries) than climate warming (decades), so in the short-term, tree reproduction will be reduced because masting has become less effective at satiating seed predators. Over the long-term, evolutionary responses to climate change could potentially increase inter-annual variability of seed production of masting species.

Fine-scale spatial genetic structure, mating, and gene dispersal patterns in Parkia biglobosa populations with different levels of habitat fragmentation.

PremiseA good understanding of genetic variation and gene dispersal in tree populations is crucial for their sustainable management, particularly in a context of rapid environmental changes. West African Sudanian savannahs are being fragmented and degraded, partly due to expansion of crop cultivation and monocultures that reduce tree density and may impact pollinators. The population dynamics of important indigenous trees could also be affected. We investigated the influence of habitat fragmentation on patterns of genetic diversity and gene dispersal of a key Sudanian agroforestry tree species, Parkia biglobosa.MethodsUsing 10 highly polymorphic nuclear microsatellites, we genotyped 2475 samples from reproductive trees, seedlings, and embryos in four tree populations presenting different levels of habitat fragmentation.Results Parkia biglobosa presented similar high genetic diversity across the four populations studied. Genetic diversity and inbreeding were similar between adults and embryo cohorts. In all four populations, the selfing rate was less than 1%. The effective number of pollen donors per tree was high (N EP~ 18–22), as was the pollen immigration rate (from 34 to 74%). Pollen dispersal was characterized by a fat‐tailed distribution with mean estimates exceeding 200 m. In three populations, stem diameter had a pronounced effect on male reproductive success. Here, the highest male reproductive success was observed in trees with a diameter at breast height between 60 and 75 cm.ConclusionsAt the scale analyzed, fragmentation does not seem to pose limitations to gene flow in any of the sites investigated, regardless of the landscape configuration associated with the different tree stands. The study provides useful insights on the reproductive biology of an important tree species in the West African savannahs.

Longer duration flooding reduces the growth and sexual reproductive efforts of a keystone wetland tree species

Wetland forests are dependent on flooding; however, general relationships between flooding and tree responses have been elusive, partly due to often coarse characterisations of flooding. In a novel approach, we used individual tree-scale water level data to assess the effect of flooding duration on a keystone wetland tree species. We surveyed 140 Eucalyptus camphora (Mountain Swamp Gum) trees across a swamp forest in both 2012 and 2019. We used TUFLOW to model daily water levels for the period from 2009 to 2019 and determined the flooding history for each surveyed tree. We then assessed the effect of flooding duration and tree size on the survival, growth, condition and extent of sexual reproduction of individual trees. Longer flooding durations limited the basal area growth of larger trees and reduced extent of sexual reproduction. Larger trees had greater basal area growth and signs of sexual reproduction overall. There were no clear effects of flooding duration or tree size on survival or condition. We suggest that for flood-tolerant tree species, prolonged (but not chronic) flooding is likely to result in slower-growing smaller trees potentially without impacts on condition or survival, and that slow tree growth and vegetative regeneration are important strategies for persistence in swamps.

Impact of grazing intensities on reproduction patterns of elm trees (Ulmus pumila) in degraded sandy lands in China.

The effect of grazing on patterns of reproduction in trees has been little reported. We explored the effects of grazing intensities on reproductive growth, allocation patterns, and duration in elm trees (Ulmus pumila L.) at the Horqin Sandy Land, a degraded area in northern China. Current-year shoots were selected from branches and harvested from individual elm trees subjected to one of four grazing intensities (heavy, moderate, light, and no grazing). Shoots, flower buds, flowers, seeds, leaf buds, and leaves were collected, dried, and weighed. Results showed that the biomass in heavy, moderate and light grazing treatments is significantly higher than in no grazing treatment (P < 0.05). The reproductive allocation of U. pumila in heavy grazing treatment was significantly higher from that in the no grazing treatment (P < 0.05). Additionally, we found that reproduction of U. pumila ended later in grazed plots, suggesting the duration of reproduction is extended with grazing disturbance. Our findings suggest that U. pumila may prolong it s duration of reproduction and alter its reproductive biomass in response to grazing. It is not clear whether these effects are related to damage to U. pumila trees by grazers or whether they are due to grazers affecting soil properties or plant competitors around U. pumila trees.

Продуктивність і стан насаджень cосни чорної австрійської (Pinus nigra var. austriaca Asch. et Gr.) у центральній та північно-східній частинах України

Наведені результати обстеження насаджень сосни чорної австрійської в Кіровоградській, Харківській і Сумській областях у 2017 та 2018 рр. В умовах Лісостепу та Степу досліджено 4 деревостани віком 27–117 років, лісові культури 27-річного віку є потомством найстарішого з обстежених деревостанів. Оцінювання насаджень проведено за ростом, якістю стовбурів, станом, а також показниками репродукції. Для комплексного оцінювання деревостанів використано 3-балову шкалу. В усіх обстежених насадженнях сосна чорна поступається сосні звичайній за висотою, але у 2 із 5 випадків перевищує її за діаметром; характеризується стовбурами більшої якості та кращім станом. За результатами комплексного оцінювання сосна чорна австрійська набрала більшу або таку саму кількість балів, як і сосна звичайна. Підтверджено перспективність застосування сосни чорної для створення лісових і захисних насаджень на еродованих ґрунтах. У разі помірного рекреаційного навантаження вона спроможна виконувати меліоративні функції, а завдяки своїй високій декоративності придатна для садово-паркового будівництва.

Micropropagation of valuable walnut genotypes for timber production: new advances and insights

The intensive production of timber from walnuts is mainly hampered by the scarcity of varieties for this purpose. While the hybrid progeny Mj209xRa is considered suitable for timber production in Europe, problems associated with its recalcitrance, the low ability for rooting and the high mortality of acclimated vitroplants, limit the reproduction of elite trees. This research was aimed to assess the influence of two methods for the in vitro introduction of several walnut genotypes, to determine the effects of temporary immersion systems (TIS) on proliferation and rooting, and to reduce the random losses of acclimated vitroplants. Hence, trees from Mj209xRa progeny as well as some common walnuts were used. As an outstanding result, the in vitro establishment of 6 out of 7 trees was obtained. Also important was the improving of quality of microshoots, the multiplication ratios and the rooting using TIS through the management of the kind of bioreactor, the volume of culture media, and the kind of explant inoculated. The direct transplant to field nursery of acclimated vitroplants considerably increased their quality, while mortality was highly reduced. Certainly, these results represent a great contribution to the current micropropagation protocol, especially with the potential introduction of TIS for massive plant production

Investigating the relationship between climate, stand age, and temporal trends in masting behavior of European forest trees.

Masting—temporally variable seed production with high spatial synchrony—is a pervasive strategy in wind‐pollinated trees that is hypothesized to be vulnerable to climate change due to its correlation with variability in abiotic conditions. Recent work suggests that aging may also have strong effects on seed production patterns of trees, but this potential confounding factor has not been considered in previous times series analysis of climate change effects. Using a 54 year dataset for seven dominant species in 17 forests across Poland, we used the proportion of seed‐producing trees (PST) to contrast the predictions of the climate change and aging hypotheses in Abies alba, Fagus sylvatica, Larix decidua, Picea abies, Pinus sylvestris, Quercus petraea, and Quercus robur. Our results show that in all species, PST increased over time and that this change correlated most strongly with stand age, while the standardized precipitation–evapotranspiration index, a measure of drought, contributed to temporal trends in PST of F. sylvatica and Q. robur. Temporal variability of PST also increased over time in all species except P. sylvestris, while trends in temporal autocorrelation and among‐stand synchrony reflect species‐specific masting strategies. Our results suggest a pivotal role of plant ontogeny in driving not only the extent but also variability and synchrony of reproduction in temperate forest trees. In a time of increasing forest regrowth in Europe, we therefore call for increased attention to demographic effects such as aging on plant reproductive behavior, particularly in studies examining global change effects using long‐term time series data.

2019 Julie S Denslow &amp; Peter Ashton Prizes for the Outstanding Articles Published in Biotropica

2019 Julie S Denslow &amp; Peter Ashton Prizes for the Outstanding Articles Published in <i>Biotropica</i>

Proposing the solar-wind energy flux hypothesis as a driver of inter-annual variation in tropical tree reproductive effort.

The El Niño Southern Oscillation (ENSO) affects tropical environmental conditions, potentially altering ecosystem function as El Niño events interact with longer-term climate change. Anomalously warm equatorial Pacific Ocean temperatures affect rainfall and temperature throughout the tropics and coincide with altered leaf flush phenology and increased fruit production in wet tropical forests; however, the understanding of mechanisms underlying this pattern is limited. There is evidence that increases in tropical tree reproduction anticipate El Niño onset, motivating the continued search for a global driver of tropical angiosperm reproduction. We present the solar-wind energy flux hypothesis: that physical energy influx to the Earth's upper atmosphere and magnetosphere, generated by a positive anomaly in the solar wind preceding El Niño development, cues tropical trees to increase resource allocation to reproduction. We test this hypothesis using 19 years of data from Luquillo, Puerto Rico, correlating them with measures of solar-wind energy. From 1994 to 2013, the solar-wind energy flux into Earth's magnetosphere (Ein ) was more strongly correlated with the number of species fruiting and flowering than the Niño 3.4 climate index, despite Niño 3.4 being previously identified as a driver of interannual increases in reproduction. Changes in the global magnetosphere and thermosphere conditions from increased solar-wind energy affect global atmospheric pressure and circulation patterns, principally by weakening the Walker circulation. We discuss the idea that these changes cue interannual increases in tropical tree reproduction and act through an unidentified mechanism that anticipates and synchronizes the reproductive output of the tropical trees with El Niño.

Effects of forest fragmentation on Ficus adhatodifolia Schott ex Spreng phenology and on its interactions with wasps

Forest fragmentation can reduce population size, affecting the plant species and their biological interactions. We evaluated the effects of fragmentation on Ficus adhatodifolia Schott ex Spreng population, aiming to answer two questions: (1) is population size sufficient to maintain reproductive fig trees throughout the year? (2) Is the mean seed production per syconium higher in the larger forest fragments? Fifty-six trees of F. adhatodifolia were visited in a year, in five fragments and one urban area in southern Brazil. Mature syconia were collected and the seed and wasp production between areas were compared. Considering all forest remnants, we recorded syconia production throughout the year, but no fragment exhibited crop production in all months. The pollinator wasps Tetrapus sp. were found in almost all syconium, thus, indicating that Ficus-pollinator mutualism was not lost. Nevertheless, smaller fragments were not capable of maintaining reproductive individuals throughout the year, therefore, requiring pollinator wasps from other fragments. The size of fragments did not influence seed production [LRT P value = 0.1; LR stat (χ2) = 4.64; n = 370]. Factors such as Ficus resilience and pollinating wasp migration may have contributed to the support of mutualism so far. Therefore, in highly fragmented landscapes such as the study region, the conservation of all forest remnants is essential to mutualistic interaction preservation. This procedure combined with the restoration of degraded areas determined by law are urgent and necessary for the conservation of regional biodiversity.

The biogeochemical niche shifts of Pinus sylvestris var. mongolica along an environmental gradient

Elemental stoichiometry has recently been integrated with trait diversity metrics to explore the effects of relative balance of multiple elements on environmental fitness of species from the perspective of biogeochemical niche (BN). Nevertheless, there is relatively little knowledge about the variability of intraspecific BN in response to environmental changes as well as how BN flexibility is related to the ecophysiological traits of species.Here we detected the BN shifts of Pinus sylvestris var. mongolica populations along an environmental gradient in northeastern China, with differences in aridity severity and soil nutrient availability. Meanwhile, we also assessed whether the BN characteristics observed are associated with the growth and reproduction of pine trees at the population level.The results indicate that the elemental and stoichiometric compositions of pine trees differed significantly, implying a BN discrimination among distinct populations. The intra-population individual stoichiometric diversity reduced with increasing aridity and decreasing soil nutrient availability, indicating the contraction of BN with increasing environmental stress. Additionally, the results also revealed a generally negative correlation between the tissue stoichiometric diversity and the reproductive traits of pine trees among different sets of populations. For example, we found pine stoichiometric richness and divergence were negatively related to cone weight and volume at the population level.The current work thus provides empirical evidence of a highly contractive BN space formed by a small set of optimal elemental phenotypes appears as a resource of species populations to respond to more stressed environments. The intraspecific BN variabilities caused by individual elemental differences are probably related to the functional performance of species.

The loss of functional diversity: A detrimental influence of landscape‐scale deforestation on tree reproductive traits

Abstract Agricultural activities such as crop production and cattle ranching are rapidly replacing forests worldwide, especially in the tropics. Resulting forest loss can adversely affect biodiversity in many ways, including trajectories of community reassembly, community composition, forest structural profiles and taxonomic diversity. Yet, effects of forest loss on specific ecosystem functions remain limited. Processes closely linked with tree reproduction, such as pollination and seed dispersal are of paramount importance for many ecological functions in tropical forests. Disruption in these processes is known to delay or change forest regeneration, diversity and structural dynamics. To explore how reproductive and dispersal traits are being altered by landscape‐scale deforestation, we surveyed and compiled trait data for tree communities in 20 tropical Atlantic rainforest remnants in northeastern Brazil, across a gradient of deforested landscapes, each retaining 3%–93% forest cover. The functional richness of reproductive plant attributes decreased as the amount of forest cover decreased, while divergence increased along the same gradient. Loss of forest cover disproportionately affected certain dispersal and reproductive attributes, with most heavily impacted functional attributes including: brief flowering duration, hermaphrodite sexual system, and zoochoric dispersal mode. We identified a clear threshold at 25–30% of forest cover, below which, reproductive attributes disappeared more quickly than expect from forest remnants. Synthesis. Deforestation may impair tree community functional diversity, particularly by decreasing the number of functions. Under scenarios of extensive deforestation, changes to reproductive and dispersal trait profile of forest communities suggest that profound modifications in the availability of floral and seed resources are likely to be substantial. Such extensive changes to food supply of pollinating and dispersing animals suggest carry‐over effects to the fauna of these important forest systems.

Seed and pollen dispersal distances in two African legume timber trees and their reproductive potential under selective logging.

The natural regeneration of tree species depends on seed and pollen dispersal. To assess whether limited dispersal could be critical for the sustainability of selective logging practices, we performed parentage analyses in two Central African legume canopy species displaying contrasted floral and fruit traits: Distemonanthus benthamianus and Erythrophleum suaveolens. We also developed new tools linking forward dispersal kernels with backward migration rates to better characterize long-distance dispersal. Much longer pollen dispersal in D.benthamianus (mean distance dp =700m, mp =52% immigration rate in 6km2 plot, s=7% selfing rate) than in E.suaveolens (dp =294m, mp =22% in 2km2 plot, s=20%) might reflect different insect pollinators. At a local scale, secondary seed dispersal by vertebrates led to larger seed dispersal distances in the barochorous E.suaveolens (ds =175m) than in the wind-dispersed D.benthamianus (ds =71m). Yet, seed dispersal appeared much more fat-tailed in the latter species (15%-25% seeds dispersing >500m), putatively due to storm winds (papery pods). The reproductive success was correlated to trunk diameter in E.suaveolens and crown dominance in D.benthamianus. Contrary to D.benthamianus, E.suaveolens underwent significant assortative mating, increasing further the already high inbreeding of its juveniles due to selfing, which seems offset by strong inbreeding depression. To achieve sustainable exploitation, seed and pollen dispersal distances did not appear limiting, but the natural regeneration of E.suaveolens might become insufficient if all trees above the minimum legal cutting diameter were exploited. This highlights the importance of assessing the diameter structure of reproductive trees for logged species.

Endothelins and their receptors in embryo implantation.

As a critical stage of pregnancy, the implantation of blastocysts into the endometrium is a progressive, excessively regulated local tissue remodeling step involving a complex sequence of genetic and cellular interplay executed within an optimal time frame. For better understanding the causes of infertility and, more importantly, for developing powerful strategies for successful implantations and combating infertility, an increasing number of recent studies have been focused on the identification and study of newly described substances in the reproductive tree. The endothelins (ET), a 21-aminoacidic family of genes, have been reported to be responsible for the contraction of vascular and nonvascular smooth muscles, including the smooth muscles of the uterus. Therefore, this review aims to comprehensively discuss the physiological role ofendothelins and signaling through their receptors, as well as their probable involvement in the implantation process.

Genetic diversity and structure of Drimys brasiliensis in southern Brazil: insights for conservation

Population genetics studies are widely recognized for generating useful knowledge for biodiversity conservation. To date, however, little is known about the levels and distribution of genetic diversity of Drymis brasiliensis (Miers LC), a tree species from the Atlantic Rainforest. Therefore, in this study, we investigated how genetic diversity is distributed within and among populations of D. brasiliensis from southern Brazil using allozyme markers to genotype reproductive trees (8 populations) and seedlings (3 populations). Furthermore, in two populations, we established two permanent plots (5.1 and 1 ha) to analyze fine-scale genetic structure (FSGS). Studied populations presented low levels of genetic diversity (reproductive = 0.085; seedlings = 0.054) and high fixation indexes (reproductive = 0.396; seedlings = 0.231). Genetic divergence among populations was equal to 0.05, which is significant, signaling that few populations can conserve large portions of the species total genetic diversity. FSGS was only detected for one population, when reproductive individuals were separated by less than 40 m. Low genetic diversity combined with high fixation indexes clearly signal a risk of losing diversity. Therefore, conservation efforts should be aimed at enhancing gene flow within the studied populations.