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Chromosomal variability in peripheral populations of malaria mosquitoes of the Anopheles genus (Diptera, Culicidae) inhabiting the territory of Karelia has been studied. The modern northern limits of the ranges inhabited by sibling species of malarial mosquitoes An. beklemishevi, An. daciae, An. messeae s. s. and An. maculipennis were established. After 2010, the boundary of distribution of malaria mosquitoes shifted northward by 170 km, from the 65th parallel to the Arctic Circle. Inversion heterozygotes XL1, XL2, 2R2, 3R1, and 3R5 were found in peripheral populations of An. beklemishevi. Peripheral populations of An. messeae s. s. were homozygous for inversion of sex chromosome XL1 and differed in the frequencies of autosome inversions from the middle taiga populations. The frequency of heterozygotes for autosomal inversions 2R1, 3R1, and 3L1 increased in populations at the edge of the species range. Chromosomal variability in peripheral populations contributes to the dispersal of malaria mosquitoes in high latitudes under warming climate conditions. [ABSTRACT FROM AUTHOR]

Context: Habitat fragmentation is expected to erode genetic diversity, which instead needs to be preserved for promoting species adaptation to a changing climate. As this expectation has found mixed support in forest trees, consistent results on the genetic consequences of fragmentation requires adequately replicated experimental designs, as well as an explicit assessment of which landscape features, if any, could mitigate its detrimental effects. Objective: Evaluating the role of several landscape attributes in buffering the detrimental effects of fragmentation in two metapopulations of silver fir. Methods: We genotyped 904 silver fir (Abies alba Mill.) trees from 18 local populations forming two metapopulations comparable for size and extension in the Apennines, a Mediterranean mountain range. We identified the signatures left by the fragmentation process on the genetic features of silver fir local populations. After removing potentially confounding effects due to different evolutionary histories, we used a multivariate approach for testing the relative effect of demographic, geographic, environmental and topographic factors on genetic features of both metapopulations. Results: We found comparable signals of the habitat fragmentation impact on the genetic diversity and structure of both investigated metapopulations. Fragmentation effects were less pronounced in the largest local populations (but not the least isolated), located on gentler slopes with higher soil water availability and lower heat exposure. Conclusions: Our results suggest the existence of a set of demographic and environmental factors that could have coherently buffered the detrimental genetic effects of fragmentation in both metapopulations. These findings could be useful to plan landscape restoration for the evolutionary rescue of mixed forests that once characterized Mediterranean mountain ecosystems. [ABSTRACT FROM AUTHOR]

The Brazilian coast presents diverse abiotic characteristics, such as temperature, and we know that surface seawater temperatures are rising as a result of climate change. Therefore, to better interpret the effects of such changes, we chose to investigate Gracilariopsis tenuifrons, a species of red algae widely occurring on the Brazilian coast. We specifically evaluated the effect of different temperatures (18–35 °C) on growth rates (GRs), photosynthetic parameters, and pigment contents of female gametophytes from five different populations distributed along 7450 km of coastline, including Maranhão State (MA, 2.4°S), Rio Grande do Norte State (RN, 5.4°S), Bahia State (BA, 14.48°S), and São Paulo State (SP1, 23.5°S and SP2, 24.2°S). All samples tolerated temperatures between 18 and 33 °C, but none of them could tolerate temperatures of 35 °C, irrespective of the populations. However, the highest GRs varied among populations (MA, 23–30 °C; RN, 28–33 °C; BA, 23–28 °C; SP1, 25–28 °C; SP2, 28 °C). MA and BA populations showed the highest maximal measurement (µmax) of the thermal performance curve when compared to SP1 and SP2 populations. The RN population showed the worst µmax values, 5.6% day−1; however, it was more resilient to stressful temperatures (33 °C) than the others. The BA population presented some physiological characteristics similar to populations from the northeastern and southeastern regions. Our data showed that Gp. tenuifrons presents latitudinal ecotypes associated with temperature. Northeastern populations could be more vulnerable in a drastic scenario of climate change (up to 4 °C); otherwise, this species could occupy regions further to the south of its current distribution. [ABSTRACT FROM AUTHOR]

Background: The Chinese mitten crab (Eriocheir sinensis) and the Japanese mitten crab (E. japonica) of the family Varunidae, which are also critical fishery species in their native habitats, including China, Japan, and South Korea, exhibit a rare migration life history for the decapod life cycle. Eriocheir sinensis and E. japonica in South Korea may have originated from speciation or secondary contact in South Korea after speciation of these two species; however, the genetic relationship between these South Korean populations remains unclear, and need to be clarified. Objective: This study examined the population genetic properties of E. sinensis and E. japonica in South Korea to reveal the origin of their co-existence. Methods: Mitochondrial DNA cytochrome c oxidase I sequences of 120 E. sinensis and E. japonica from 6 sampling sites in South Korea were sequenced. Their genetic diversity and haplotype data were compared to previously reported data from the Chinese mainland, Taiwan, Japan, and Russia. Results: The haplotype network, analysis of molecular variance, FST values, Mantel test, and Bayesian skyline plot results of South Korean E. sinensis and E. japonica demonstrated that E. sinensis and E. japonica were isolated from their central populations, Chinese and Japanese populations, by the distance due to the temperature, salinity, ocean current flow, or a geohistorical event. In addition, genetic analysis indicated that the South Korean populations of the two species were marginal populations, exhibiting low genetic diversity, significant negative neutrality values, and radial haplotype networks. The current results also suggest that the Geum River is an overlapping habitat for the natural populations of E. sinensis and E. japonica in South Korea. Further research is required to examine the geohistorical and evolutionary event between E. sinensis and E. japonica in South Korea. Conclusions: The co-existence of E. sinensis and E. japonica in South Korea may have originated from secondary contact after their speciation. [ABSTRACT FROM AUTHOR]

Key message: Lowered pollen and seed quality of B. humilis compared to its widespread tree relatives may threaten its populations at the southwestern edge of the species range. Inability to produce vital propagules is the main threat to the persistence of rare plants at the edges of species distribution. In the present investigation, factors responsible for the low germinability of shrub birch (Betula humilis) seeds in the peripheral populations were analysed. As shrub birch populations are found in phosphorus (P)-limited peatlands with high groundwater levels, the impact of groundwater PO43− ion contents and groundwater table for B. humilis flowering was also studied. Qualities of the B. humilis seeds and pollen were compared to those of tree congeners silver birch (B. pendula) and downy birch (B. pubescens), which usually represent a high reproductive performance. We revealed that the poor germination ability of B. humilis seeds was caused by the high proportions of empty seeds (44.8%) and seeds with partially developed embryos (47.3%). The insufficient numbers of viable seeds may be a consequence of low-quality shrub birch pollen, as only 1.6% of pollen grains sprouted. The germinability of shrub birch pollen was significantly lower than that of Betula tree pollen; thus, there is a risk of pollination of B. humilis female flowers by pollen grains of tree birches. Positive relationships between the P concentrations in seeds and seed germinability were revealed in tree birches, but not in B. humilis. The availability of PO43− ions in the groundwater did not affect B. humilis flowering, but male inflorescences were more numerous in stands with higher groundwater levels. Consequently, the maintenance of peatlands is crucial for the efficient sexual reproduction of shrub birches. [ABSTRACT FROM AUTHOR]

Range marginal populations are often perceived to have lower conservation value compared to those in the core area. The allocation of resources to maintain peripheral populations is therefore often questioned. The sage-leaved rockrose (Cistus salviifolius L.) is a self-incompatible and obligate seeder widely distributed in the Mediterranean area but rare and patchily distributed in Switzerland at its range margin on the southern slopes of the Alps. Here, we combined analysis of genetic diversity with pollinator surveys and field studies of reproductive ecology to compare peripheral Cistus populations in the Alps with range central populations in the Mediterranean. Our results showed no differences in genetic diversity between peripheral and central populations and between fragmented and connected ones at its range margin in the Alps. Although the fragmented populations were visited by more abundant and species richer pollinators (bees and wasps), they showed lower number of seeds and higher self-compatibility compared to the connected ones, which excludes the pollination limitation hypothesis. Overall, our study highlights that peripheral populations of C. salviifolius in the Alps are likely to contribute to maintain genetic diversity, while showing variation in reproductive ecology, and are therefore important for the conservation of this species. [ABSTRACT FROM AUTHOR]

The performance of populations at the edge of specie’s distribution range may differ substantially from central populations. Here, we develop a modelling framework to estimate ecological niches (i.e. climatic) of four locally endangered plant species and measure the distance of marginal (geographically) populations to the species’ niche centroid in order to analyse whether marginal populations are outside of the optimal ecological niche of each species. Our results show that for three of the four studied species, which have their populations located at the margins of their distribution ranges, are also at the margins of their climate gradients. These results would support the hypothesis that marginality within the set of habitable conditions (i.e. ecological niche) may represent an important determinant on performance of some plant populations, as well as a plausible explanation to the degree of stagnancy or regression experienced by species in those regions where their populations are at the margin of their ecological niche and/or they are restricted to microrefugia with ecological conditions very different from those around them. Finally, this study aims to be a theoretical base from which to advance on, including other types of factors (e.g. biotic interactions, topography, human influence and population fluctuations through time), which will allow for a better understanding of the complex network of factors that occur in marginal plant populations. [ABSTRACT FROM AUTHOR]

Peripheral sites usually offer suboptimal conditions for species with wide distributions, where expression of phenotypic variability and potential interspecific hybridization might be enhanced. The Patagonian steppe, the largest and southernmost dryland ecosystem in South America, is characterized by natural rangelands dominated by grasses. Festuca pallescens is a keystone species with a wide distribution in Patagonia over diverse environments reaching the extreme arid zones in the Somuncura plateau, a biogeographical island. Our aim is to study the phylogenetic relationships among Festuca pallescens populations as well as between this species and the sympatric F. argentina in North Patagonia. We analysed fourteen populations along a west-east transect of about 500 km in North Patagonia with three types of molecular markers: ITS, chloroplast trnL-F and eight nuclear microsatellites. Bayesian inferences, maximum parsimony and maximum likelihood analyses with trnL-F and ITS showed that F. pallescens is related to the Patagonian clade within the Festuca phylogeny. However, the easternmost populations of F. pallescens at Somuncura plateau were highly differentiated from the other populations and clustered with F. argentina (a sympatric species of the Asian-American clade). Principal coordinates analyses and Bayesian clustering performed with nuclear microsatellites as well as morphoanatomical traits, showed an intermediate position of one of these easternmost populations with respect to the two species, suggesting admixture. The high genetic variability observed in these peripheral populations highlight their relevance for conservation and might be indicating the existence of evolutionary processes triggering events of speciation in the Patagonian fescues. [ABSTRACT FROM AUTHOR]

The aim of our study was to determine variation in the response of radial growth in Fagus sylvatica L (European Beech) to climate across the species full geographical distribution and climatic tolerance. We combined new and existing data to build a database of 140 tree-ring chronologies to investigate patterns in growth-climate relationships. Our novel meta-analysis approach has allowed the first investigation of the effect of climate on tree growth across the entire geographical distribution of the species. We identified key climate signals in tree-ring chronologies and then investigated how these varied geographically and according to mean local climate, and by tree age and size. We found that the most important climate variables significantly correlated with growth did not show strong geographical patterns. Growth of trees in the core and at the southern edge of the distribution was reduced by high temperature and low precipitation during the growing season, and by high temperatures in the previous summer. However, growth of trees growing in warmer and drier locations was more frequently significantly correlated with summer precipitation than other populations. Additionally, the growth of older and larger trees was more frequently significantly correlated with previous summer temperature than younger and smaller trees. Trees growing at the south of the species geographical distributions are often considered most at risk from climate change, but our results indicate that radial growth of populations in other areas of the distribution is equally likely to be significantly correlated with summer climate and may also be vulnerable. Additionally, tree-rings from older trees contain particular growth-climate relationships that are rarely found in younger trees. These results have important implications for predicting forest carbon balance, resource use and likely future changes to forest composition across the continent. [ABSTRACT FROM AUTHOR]

The adaptive potential of populations and therefore their ability to cope with rapid environmental changes is a question of paramount fundamental and applied importance. However, what is still not clear is the effect of population position within the species range (i.e. core vs. edge) on population adaptive potential, and whether the adaptive potential can be predicted from extent of neutral molecular variation. In this study, we compared the extent and structure of neutral (SSR) and presumably adaptive quantitative trait genetic variation in populations of Triticum dicoccoides sampled at the species range core and two opposite edges, and related this information to multigenerational performance of plants experimentally introduced beyond the range edge. The plants from the species arid edge performed worse than plants from the more mesic core in extreme desert conditions. The core and edge populations did not differ in extent of SSR variation. In contrast to the neutral genetic variation, there was lower quantitative trait variation in the two edge as compared with the core population for many traits, and no trait in any edge population had higher variation than the core population or either of its habitats. Reduced variation in selectively important traits indicates a lower adaptive potential of the two edge as compared with the core population. Our results imply (1) that extent of variation in quantitative traits can predict plant performance in novel environments while extent of variation in molecular markers can not; and (2) caution in usage of peripheral populations in such conservation actions as relocation and creation of new populations. We also warn against usage of neutral molecular variation as a surrogate for selectively important quantitative variation in conservation decisions. [ABSTRACT FROM AUTHOR]

Polymorphism of the main morphological characteristics of Siberian spruce ( Picea obovata Ledeb.), which are used for diagnosing the species, as well as the population structure, was studied at the northern limits of the species habitat and compared with characteristics of spruce from the central regions of the area. The results obtained give an insight into the population structure of Siberian spruce and a pattern of its variation within the area. [ABSTRACT FROM AUTHOR]

The probability of population extinction seems to differ within the species range. Populations occupying former glacial refugia could harbor substantial genetic resources, hence they should be less prone to extirpation. It was hypothesized that the shrub birch Betula humilis could have survived the Last Glacial Maximum (LGM) at the current southwestern margin of its range. Using ten nuclear microsatellites, we studied genetic variation within and between 18 localities of B. humilis situated in marginal and subcentral areas. Six marginal populations were located in areas covered by an ice sheet during the LGM, and the remaining samples came from unglaciated areas. Analysis of private allele frequencies as well as hierarchical AMOVAs conducted for geographical regions, marginal versus central populations, and glaciated versus unglaciated areas did not confirm the hypothesis of glacial isolate of the shrub birch in southeastern Poland. On the other hand, very high genetic variation in some localities in northeastern Poland was found. Survival in periglacial areas followed by broad-fronted colonization or the existence of an admixture zone of phylogeographic lineages was proposed to explain this phenomenon. [ABSTRACT FROM AUTHOR]

The IUCN criteria 2001 are considered one of the best methods to evaluate species extinction risk at the global and regional levels. The aim of this work is to test the applicability of the IUCN criteria to peripheral isolated plant populations (PIPPs). PIPPs have been a topic of scientific debate in Conservation Biology for about 15 years and international conventions such as ESPC address the issue of their conservation. Conservation measures often rely on Red Lists based on IUCN criteria, but there is little evidence supporting their application to PIPPs. In this work, we tested the hypothesis that PIPPs' intrinsic restricted range and rarity lead to the overestimation of their extinction risk. We compared and analyzed four IUCN criteria (A, B, C, D), considering 17 species with PIPPs in different Italian administrative regions. Special attention must be given to the spatial scale at which PIPPs are assessed, the evaluation of the threats affecting the populations, and their decline. PIPPs should not be assessed within political boundaries and we propose a new area designation that better corresponds to the characteristics of PIPPs. Criterion B is strongly biased by restricted range and overestimates the extinction risk of PIPPs, particularly when the population decline is only suspected and not observed. In this case, criterion D more accurately assesses the status of PIPPs. Criterion A is also suitable for assessing PIPPs, because it is not affected by their phytogeographic rarity. The proposed statements could also be valid for the global assessment of narrow endemic species. [ABSTRACT FROM AUTHOR]

The processes that have shaped the extraordinary species diversity in neotropical rainforests are poorly understood, and knowledge about the patterns of genetic diversity across species' ranges is scarce, in contrast to other regions of the globe. We have conducted a range-wide study of genetic diversity in a plant endemic to the Brazilian Atlantic Rainforest, Vriesea gigantea (Bromeliaceae), based on a combined data set of nuclear microsatellites and chloroplast (cp) DNA markers typed in 429 plants from 13 populations. The results indicate a strong negative correlation between genetic diversity and population latitude, consistent with historical forest expansion from the northern half of the present distribution range. A deep phylogeographic split exists between the Brazilian states of São Paulo and Rio de Janeiro at ca. 23 °S latitude, probably reflecting past population isolation within more than one glacial refuge during the climatic changes of the Pleistocene. A comparison of genetic structures at cpDNA and nuclear markers revealed a pollen/seed flow ratio of more than 3:1, thus indicating an important role of the pollinating animals (that is, bats) in shaping the population genetic structure of this species. Diversity was reduced for cpDNA markers in the island populations off the coast, and reduced diversity and increased differentiation were observed for both nuclear and cpDNA at the edges of the species' range. The link between patterns of genetic and species diversity supports the hypothesis that both were shaped by the same biogeographic processes, triggered by the climatic oscillations of the Pleistocene. [ABSTRACT FROM AUTHOR]

Factors controlling brown trout Salmo trutta recruitment in Mediterranean areas are largely unknown, despite the relevance this may have for fisheries management. The effect of hydrological variability on survival of young brown trout was studied during seven consecutive years in five resident populations from the southern range of the species distribution. Recruit density at the end of summer varied markedly among year-classes and rivers during the study period. Previous work showed that egg density the previous fall did not account for more than 50% of the observed variation in recruitment density. Thus, we expected that climatic patterns, as determinants of discharge and water temperature, would play a role in the control of young trout abundance. We tested this by analyzing the effects of flow variation and predictability on young trout survival during the spawning to emergence and the summer drought periods. Both hatching and emergence times and length of hatching and emergence periods were similar between years within each river but varied considerably among populations, due to differences in water temperature. Interannual variation in flow attributes during spawning to emergence and summer drought affected juvenile survival in all populations, once the effect of endogenous factors was removed. Survival rate was significantly related to the timing, magnitude and duration of extreme water conditions, and to the rate of change in discharge during hatching and emergence times in most rivers. The magnitude and duration of low flows during summer drought appeared to be a critical factor for survival of young trout. Our findings suggest that density-independent factors, i.e., hydrological variability, play a central role in the population dynamics of brown trout in populations from low-latitude range margins. Reported effects of hydrologic attributes on trout survival are likely to be increasingly important if, as predicted, climate change leads to greater extremes and variability of flow regimes. [ABSTRACT FROM AUTHOR]

In order to understand better the ecology of the temperate species Quercus petraea and the sub-Mediterranean species Quercus pyrenaica, two deciduous oaks, seedlings were raised in two contrasting light environments (SH, 5.3% full sunlight vs. HL, 70% full sunlight) for 2 years, and a subset of the SH seedlings were transferred to HL (SH–HL) in the summer of the second year. We predicted that Q. pyrenaica would behave more as a stress-tolerant species, with lower specific leaf area (SLA), allocation to leaf mass, and growth rate and less responsiveness to light in these metrics, than Q. petraea, presumed to be more competitive when resources, especially light and water, are abundant. Seedlings of Q. petraea had larger leaves with higher SLA, and exhibited a greater relative growth rate (RGR) in both SH and HL. They also displayed a higher proportion of biomass in stems (SMF), and a lower root to shoot ratio (R/S) in HL than those of Q. pyrenaica, which sprouted profusely, and had higher rates of photosynthesis (An) and stomatal conductance (gwv), but lower whole-plant net assimilation rate (NAR). On exposure to a sudden increase in light, SH–HL seedlings of both species showed a short period of photoinhibition, but fully acclimated photosynthetic features within 46 days after transference; height, main stem diameter, RGR and NAR all increased at the end of the experiment compared to SH seedlings, with these increases more pronounced in Q. petraea. Observed differences in traits and responses to light confirmed a contrasting ecology at the seedling stage in Q. petraea and Q. pyrenaica in consonance with differences in their overall distribution. We discuss how the characteristics of Q. petraea may limit the availability of suitable regeneration niches to microsites of high-resource availability in marginal populations of Mediterranean climate, with potential negative consequences for its recruitment under predicted climatic changes. [ABSTRACT FROM AUTHOR]

Corylus avellana L. (hazel, Betulaceae) is a long-lived, widespread shrub in Europe, having its northern range margin in Fennoscandia and a postglacial history involving range-expansion from refugial areas in southern Europe. In this study, we tested for a relationship between marginality and low within-population genetic diversity by assessing patterns of variation at 14 putatively neutral allozyme loci (comprising 43 putative alleles) within and between 40 natural populations of C. avellana along a north-south transect in Europe. Geographically marginal populations (central Sweden) showed lower levels of within-population diversity than populations in more central regions, as indicated by significant negative correlations between latitude and the percentage of polymorphic loci (rS=–0.47, P < 0.001), the average number of alleles per locus (rS=–0.65, P < 0.001), the expected heterozygosity (rS=–0.19, P < 0.05), and the proportion of distinguishable genotypes (rS=–0.56, P < 0.001). These patterns, combined with the unusually high between-population component of gene diversity (GST=19.7%) and allelic richness (AST=24%) in the marginal region, can be attributed to historical bottlenecks during the species’ postglacial range-expansion, but may also reflect a history of genetic drift in the small, isolated populations occupying the marginal region. Information on the spatial distribution of genotypes provide further support for a role of vegetative reproduction (layering) in the structuring of genetic variation within populations. [ABSTRACT FROM AUTHOR]

Genetic structure and genetic diversity in fourteen autochthonous populations of Pinus sylvestris L. from the Iberian peninsula and two populations from the Massif Central in France were studied at eleven isoenzymatic polymorphic loci. The studied populations formed two genetically similar but heterogeneous groups. The first group consist of populations localized in North-Eastern Spain with two genetically distinct populations. The second includes populations of the West-Central part of the Iberian peninsula. Populations from the Massif Central in France are diverse from those of Spain, but are similar to the group from North- part of the Iberian peninsula. The existence of significant numbers of private alleles in Spanish populations which were not observed in populations from the Massif Central, suggests that the Scots pine from the Iberian peninsula probably did not take part in the colonization of Europe after the last glaciations and represents original ancient tertiary gene pools. [ABSTRACT FROM AUTHOR]

To test if the high nutrient inputs of agroeosystems select for specialized agroecotypes or for phenotypic plasticity, Ontario populations of the northwardly migrating annual weed Solanum ptycanthum from ruderal (beach) and agricultural habitats were compared over a nutrient gradient. Temporal variation of total available nitrogen was determined in both types of habitats. As gene flow via seed contamination of tomato transplants from S. United States was detected, variation in response to nutrient (N) levels was also compared between agrestal populations from the northern (Ontario) and southern (Georgia) ends of the species range. Five families from six populations (two northern agrestal, two northern ruderal and two southern agrestal) were grown in the greenhouse at low, medium and high nutrient levels, and plant growth and traits associated with reproductive success measured. All populations displayed significant levels of plasticity in the majority of vegetative and reproductive traits. There were no detectable differences over the levels of nutrients tested between individuals sampled from northern agrestal and ruderal populations, even though variation in available nitrogen is greater in agroecosystems. Southern agrestal populations were genetically differentiated from the northern populations, and exhibited almost twice the overall plasticity of northern populations, measured by the Mahalanobis distance. Canonical discriminant analysis showed complete overlap in the northern populations over all nutrient levels, suggesting that colonization of new habitats is via a general-purpose genotype, rather than by selection for specialized agroeotypes. [ABSTRACT FROM AUTHOR]

The genetic structure of populations at the edge of species distribution is important for species adaptation to environmental changes. Small populations may experience non-random mating and differentiation due to genetic drift but larger populations, too, may have low effective size, e.g., due to the within-population structure. We studied spatial population structure of pedunculate oak, Quercus robur, at the northern edge of the species' global distribution, where oak populations are experiencing rapid climatic and anthropogenic changes. Using 12 microsatellite markers, we analyzed genetic differentiation of seven small to medium size populations (census sizes 57–305 reproducing trees) and four populations for within-population genetic structures. Genetic differentiation among seven populations was low (Fst = 0.07). We found a strong spatial genetic structure in each of the four populations. Spatial autocorrelation was significant in all populations and its intensity (Sp) was higher than those reported in more southern oak populations. Significant genetic patchiness was revealed by Bayesian structuring and a high amount of spatially aggregated full and half sibs was detected by sibship reconstruction. Meta-analysis of isoenzyme and SSR data extracted from the (GD)2 database suggested northwards decreasing trend in the expected heterozygosity and an effective number of alleles, thus supporting the central-marginal hypothesis in oak populations. We suggest that the fragmented distribution and location of Finnish pedunculate oak populations at the species' northern margin facilitate the formation of within-population genetic structures. Information on the existence of spatial genetic structures can help conservation managers to design gene conservation activities and to avoid too strong family structures in the sampling of seeds and cuttings for afforestation and tree improvement purposes. [ABSTRACT FROM AUTHOR]