Needle Characters Research Articles

Altitudinal effect on Crimean pine (Pinus nigra J.F. Arnold subsp. pallasiana (Lamb.) Holmboe) sapling morphology in north-western Türkiye

ABSTRACT Sapling morphological characters are one of the important tools for assessing the adaptive potential of a tree species to a changing environment, and so to climate change. In the study, the morphological characters of stems and needles of Crimean pine (Pinus nigra J.F. Arnold subsp. pallasiana (Lamb.) Holmboe) saplings growing in different altitudes were examined to assess the altitudinal variability. For this purpose, a total of 45 saplings and 900 needle (one- and two-year old) samples from Karabük Province of north-western Türkiye were investigated. Significant differences were observed in the morphological characters, i.e. needle length (NL), needle width (NW), needle thickness (NT), sheath length (SL), number of rows of stomata (NR), number of stomata per cm (NS), and root collar diameter (RD) of the saplings among three altitude classes (560, 756 and 968 m). RD and needle dimensions, including stomatal density, increased with altitude. Besides, there were significant differences of the needle characters between one and two years of needles, except NW and NT located in high altitude class. It was concluded that Crimean pine saplings from different altitudes can be separated from each other on the basis of the morphological characters of needles.

Morphological and Anatomical Characteristics of Moroccan Fir Needles in Talassemtane National Park, North-Western Rif Region, Morocco

Moroccan fir, Abies maroccana Trab. forms a unique forest community in the Mediterranean basin and has a great ecological and biological values in Moroccan Rif Mountains. However, morphological and anatomical characters of the needles are poorly investigated for A. maroccana. This research examined the morphological and anatomical characters of Moroccan fir needles in order to determine the phenotypic needles traits of Abies maroccana. The study was carried out in the National Park of Talassemtane, Western Rif, Morocco. Data was collected from two-year-old needles in six stands. In each site, seven trees were selected, and 60 needles were collected from each tree. Five morphological and one anatomical characters of the needles were examined. The variance analysis (ANOVA) of quantitative needles variables revealed significant inter-tree morphological variability of needles of A. maroccana. Based on the morphological characters studied, the multivariate analysis (PCA) separated all trees of Moroccan fir into four groups: (A) long, thin and large; (B) long, thin and narrow; (C) short, large and thick; and finally (D) short and thick needles. As demonstrated here, the fir needles were mainly characterized by: 2 types of apex (obtuse–acute and acute needles), a broad base and the marginal resin canals. This diversity can be attributed to genetic variation and / or influence of ecological conditions.

The length, number, and endodermis area of needles discriminate two genetically distinct populations of Cedrus atlantica Manetti in the Moroccan Middle Atlas

The variation in some adaptive characters of cedar needles was studied in two different regions of the Moroccan Middle Atlas that have different local environmental conditions and levels of genetic diversity. The two populations are localized in the Azrou and Ifrane regions. Tukey’s tests showed that the needle/brachyblast number (Nn/R), length (Nl), and needle width (Nw) showed the greatest variation. In addition, all anatomical characters studied showed a significant correlation with Nw, whereas only the area of the vascular bundles (AVb) was related to Nl. Discriminant analysis revealed that Nn/R, Nl, and the area of the central cylinder (ACc) are high-discriminating characters among populations of Azrou and Ifrane and confirms their isolation. These adaptations of the morphological and anatomical traits of the Atlas cedar needles of the Azrou and Ifrane regions are discussed in relation to the local environmental conditions and have been found to be in harmony with their genetic distinctiveness revealed previously.

Taxonomic position of Abies equi-trojani on the basis of needlecharacters by comparison with different fir species

The needles from 25 trees of Abies equi-trojani from Kazdagi (Mount Ida) were compared with those from four populations of A. alba, two of A. cephalonica, and three of each of A. xborisii-regis, A. bornmuelleriana, and A. nordmanniana, each represented by 29-31 individuals. Thirty-nine morphological and anatomical needle characters (26 main and 13 estimated ones) were examined biometrically to verify the systematic position of A. equi-trojani. To evaluate the relationships among taxa, Student's t-test for independent samples, the Mann-Whitney U test, and discrimination and clustering analyses were applied. The differences between taxa were statistically significant for several characters, but the data ranges generally overlapped between species. Morphological and anatomical characters of the needle allowed to distinguish between A. equi-trojani, A. alba, A. cephalonica, A. xborisii-regis, A. bornmuelleriana, and A. nordmanniana when used together, but no single character applied separately could distinguish between species. A close relationship of A. equi-trojani to A. bornmuelleriana and to A. nordmanniana detected based on the needle characters supported the infraspecific systematic position of these three taxa.

Genetic variation for needle traits in Scots pine (Pinus sylvestris L.)

The remnants of the Caledonian Native Pinewood are distributed across a relatively narrow geographic area in the Scottish Highlands yet inhabit a steep environmental gradient in terms of rainfall, temperature and altitude. Previous work based on common garden trials has demonstrated that native pine populations (Pinus sylvestris (L.)) exhibit differentiation in terms of growth, phenology and frost resistance. However, despite their important role in plant fitness, no such information is available on leaf traits, which have shown both plastic and adaptive genetic responses to environmental variation in other species. We analysed a subset of 11 needle characters in 192 saplings grown in a population-progeny common garden trial based on seedlots from eight native pinewoods. Narrow-sense heritability (h 2) was estimated for each trait and found to be particularly high (1.30 ± 0.33) for resin canal density. The majority of the phenotypic variation found was within populations, although interpopulation differentiation was detected for needle length (ΔAICc = 2.55). Resin canal density was positively correlated with longitude (β = 0.45, ΔAICc = 4.23), whereas stomatal row density was negatively correlated (β =−0.12, ΔAICc = 2.55). These trends may reflect adaptation for differences in moisture availability and altitude between eastern and western populations in Scotland.

Effect of geographic range discontinuity on taxonomic differentiation of Abies cilicica

Three populations of <em>Abies cilicica</em> subsp. <em>isaurica</em> and four of <em>A. cilicica</em> subsp. <em>cilicica</em> were analyzed using 35 morphological and anatomical needle characters with the implementation of multivariate statistical methods to verify the differences between subspecies. Moreover, the possible geographic differentiation of <em>A. cilicica</em> subsp. <em>cilicica</em> populations from the East Taurus and Lebanon Mountains was examined. <em>Abies cilicica</em> subsp. <em>isaurica</em> has been distinguished from <em>A. cilicica</em> subsp. <em>cilicica</em> by its glabrous young shoots and resinous buds. We detected that needles of <em>A. cilicica</em> subsp. <em>isaurica</em> are longer, broader and thicker, with a higher number of stomata rows, and larger cells of the epidermis, hypodermis and endodermis than <em>A. cilicica</em> subsp. <em>cilicica</em>. Additionally, <em>A. cilicica</em> subsp. <em>isaurica</em> needles have frequently rounded to obtuse-acute apex and resinous canals positioned more centrally inside the mesophyll than needles of <em>A. cilicica</em> subsp. <em>cilicica</em>. This indicates that a set of most of the tested needle characters can be used to distinguish the subspecies; however, any of characters enable that when used separately. Morphological and anatomical distinctiveness between these two taxa justify their recognition at the subspecies rank. Additionally, the populations of <em>A. cilicica</em> subsp. <em>cilicica</em> from the East Taurus and Lebanon are morphologically different. This geographic differentiation of populations is congruent with results provided by genetic analyses of nuclear microsatellites markers (nSSR).

Geographic distribution of quantitative traits variation and genetic variability in natural populations of Pinus mugo in Central Europe

Divergence in genetic as well as phenotypic structures can be expected in species with disjunctive geographic ranges and restricted gene flow among isolated populations. Dwarf mountain pine has such a disjunctive geographic range in the mountains of Central Europe. We hypothesised that populations of Pinus mugo from the Giant Mts. differ from Alpine and Carpathian populations to a greater extent than differentiation within these regions; furthermore, these differences would be detectable at both the genetic and phenotypic levels. To verify this hypothesis, the diversity and differentiation within and among eleven populations from the Giant Mts., Carpathians and Alps were analysed using 19 isozyme isozyme loci, 17 needle and 15 cone morphological characters. Moreover, the data on 10 chloroplast microsatellites used in the previous study, were reanalysed. The differences between the three regions were greater than among populations within them. The microsatellites and isozymes clearly differentiated between regions, while in the multivariate analyses of cone and needle characters the Alpine and Carpathian populations were intermingled but distinct from those sampled in the Giant Mts. The significant genetic structuring among regions may result from an ancient fragmentation and long lasting geographic isolation between the Giant Mts., Alps and Tatras. The populations from the Giant Mts., the northernmost within the geographic range of P. mugo, presented lower level of genetic variation then those from the Alps and Carpathians. The pattern of genetic structure observed in dwarf mountain pine may be characteristic of wind-pollinated trees with a disjunctive geographic distribution

Distance between south-European and south-west Asiatic refugial areas involved morphological differentiation: Pinus sylvestris case study

The phenotypic differentiation of relic P. sylvestris in southern Europe and southwestern Asia was verified using thirty-two populations sampled from the Iberian Peninsula, Massif Central, Balkan Peninsula, Crimea and Anatolia. Twenty-one morphological and anatomical needle traits and 18 cone morphological characteristics were examined to describe the population diversity and differentiation. The needle characters were not correlated to those of cone. The differences between regions were significant based on 12 needle and 9 cone characteristics, suggesting spatial isolation. The differentiation between the Iberian and Anatolian populations was the highest, which indicates the isolation by distance. The high level of morphological differentiation was also found among Iberian populations, supporting the already known complex history of the species in that region. Populations within other regions were differentiated at lower levels; however, the West Anatolian populations differed morphologically from the eastern ones. The described pattern of morphological differentiation supports the idea of the long-lasting existence of P. sylvestris in the south-European and Anatolian mountain regions. To conserve this variation, seed transfer between regions in the forest economy should be restricted.

MORPHOLOGICAL VARIATION IN ALEPPO PINE (PINUS HALEPENSIS MILL.) IN ISRAEL

ABSTRACT Measurements of 17 characters of cones, needles and bark were made on trees from seven provenances in Israel, and analysed by principal components analysis. Four components accounted for 62% of the total variation. Among these components the Bet Meir and Yirka provenances are similar, while the other seed sources differ from each other. There is no evidence of clinal variation; this was confirmed by analysis of four of the original variables, taken separately, although there is significant between-provenance variation. The Rosh HaNiqra seed source tends to have more extreme component values than the others. This may be due to introgression with Pinus brutia or to different selection pressure.

Morphological diversity and structure of West Mediterranean Abies species

The aim of this study was the biometrical comparison of Abies pinsapo Boiss., Abies maroccana Trab. and Abies tazaotana Côzar ex Villar from Spain and Morocco. The morphological and anatomical analysis of the needle characters of these firs revealed significant taxonomic differences. The results showed considerable distances between regions and very small differences among the Moroccan fir taxa. The examination of the needles and earlier genetic analysis did not provide evidence for distinguishing A. tazaotana at the species level.

Relationships among Cedrus libani, C. brevifolia and C. atlantica as revealed by the morphological and anatomical needle characters

The main aim of the present study was testing the value of the morphological and anatomical characteristics of the needles in distinguishing Cedrus atlantica, C. libani and C. brevifolia. Nine populations were sampled in their natural habit and 25 characters were used to describe the variation of the brachyblast needles and to analyze the differences between species. The results indicated that morphological and anatomical needle characters provide valuable tools in discrimination of the taxa. The scored differences were statistically significant, as revealed in the Tukey’s t test, discrimination analysis and hierarchical analysis of variation. The results support treating C. libani, C. atlantica and C. brevifolia as independent species.

Latitudinal variation in morphological traits of the genus Pinus and its relation to environmental and phylogenetic signals

Background: Broad-scale analysis of interspecific trait variation is a fundamental approach in comparative ecology to investigate general species–environment relationships, but inferences from environmental and phylogenetic signals are still controversially discussed. Aims: The aim of this study was to globally analyse the genus Pinus and the interspecific variation of morphological traits with latitude as a surrogate of broad-scale environmental changes, and to compare latitudinal trait correlations with biogeographic, environmental and phylogenetic signals in trait variation. Methods: Based on native range maps of 103 Pinus species, the latitudinal correlations of nine morphological traits, including needle characters, cone length and tree height were calculated. Principal component analysis was used to explore trait covariation. Variation partitioning was applied to disentangle environmental and phylogenetic signals in trait variation. Results: Strong latitudinal correlations were detected for traits, such as needle length:width ratio or needle longevity, with similar trends for different taxonomic species subsets and geographic regions. Strong latitudinal correlations were related to a decrease in the pure phylogenetic signal and to an increase in the phylogenetically structured environmental variation (PSEV), whereas the pure environmental signal was almost negligible. Conclusions: Besides a ranking of traits that differ in environmental and phylogenetic signals, our results showed a general relationship between increasing latitudinal trait correlation and an increase in PSEV, which indicates phylogenetic niche conservatism. Thus, for the investigated morphological traits of the genus Pinus both environmental and phylogenetic signals are directly linked by PSEV to broad-scale spatial patterns in trait variation.

Morphological variation of Juniperus oxycedrus subsp. macrocarpa (Cupressaceae) in three Italian localities

The intra- and interpopulational geographic variation of three distant populations of <em>J. oxycedrus </em>subsp. <em>macrocarpa </em>was examined biometrically on the basis of morphological key-characters of needles, seeds and cones. The shortest Euclidean distances were used in the agglomerative grouping of closest neighbourhood and discrimination analysis with principal component analysis (PCA) was performed to verify the south-north differentiation of the taxon in Italy. Most of the cone and seed dimensional characters are correlated. No significant correlations were found between cone and needle characters. The sampled populations differ only insignificantly from one another, while the intrapopulational variation is slightly higher. Cone length as well as seed number, width and thickness were significantly correlated with geographic latitude, while the other four characters are not. Differences in cone shape were observed between individuals, so that several morphotypes can be distinguished.

Variation of morphological needle characters of Scots pine (Pinus sylvestris L.) populations in different habitats

We investigated the phenotypic variation of five morphological needle characters of Scots pine (<em>Pinus sylvestris</em> L.) in three populations. Two of the populations occurred in bogs and the third one formed a degraded fresh pine forest showing some features of a dry pine forest. The greatest variation was found in characters a (needle length), b and d, denoting the number of stomatal rows respectively on the convex and flat sides of the needle. Conversely, characters c and e (average number of stomata per 2 mm of needle length on the convex and the flat side of the needle) were stable, with little interindividual variation. The two bog populations and the dryland population exhibited different sets of character correlations. The interpopulation differentiational detected on the basis of morphological character expression was markedly influenced by both the different edaphic conditions, and the distinct genetic structure of the studied populations.

Effect of tree age on needle morphology and anatomy of Pinus uliginosa and Pinus silvestris – species-specific character separation during ontogenesis

Differences in morphological and anatomical characters of needles between seedlings, saplings and adult trees of the endangered Pinus uliginosa from the Węgliniec Nature Reserve in SW Poland were examined biometrically and statistically assessed using the Student's t-test, Tukey–Kramer test, step-wise discrimination and agglomeration on Euclidean distances according to Ward's method. Pinus sylvestris adults and seedlings were used as comparative material. The results show that needles of all three P. uliginosa generations differ significantly from each other. In seedling needles, several anatomical characters were similar to those of P. sylvestris growing in the vicinity of the reserve. However, P. uliginosa had a lower number of resin canals, lower frequency of fibre-like sclerenchyma cells and higher frequency of thin-walled sclerenchyma cells with large lumens in the spaces between vascular bundles. Needle characters of saplings and adult trees of both species were distinctly more different than it was the case in the seedling stage.

Morphological variation of Juniperus oxycedrus subsp. oxycedrus (Cupressaceae) in the Mediterranean region

The intra- and inter-population variation of Juniperus oxycedrus subsp. oxycedrus were examined biometrically on the basis of morphological characters of needles, seeds and cones. Cluster analysis of Euclidean distances and discriminant analysis were performed to verify the hypothesis of geographic differentiation and origin from the West- and East-Mediterranean Pleistocene refugial regions. The West-Mediterranean populations of J. oxycedrus subsp. oxycedrus differed from the eastern ones. The intra-populational differentiation of three of the West-Mediterranean populations was significantly higher than within the other West- and all the East-Mediterranean ones. Results confirm the hypothesis of probable different origins of the East- and West-Mediterranean populations of the taxon.

Variation in certain characters and properties of scotch pine needles in geographic cultures

Morphophysiological and anatomical characters of needles that are used for characterizing infraspecific taxa have been studied in Scotch pine geographic cultures established in the forest-steppe zone of Siberia. Variation in these characters has been revealed, which reflects the polymorphic structure of the species and the effect of natural selection on the composition of populations in new natural-cimatic conditions.

Variation in the anatomical characters of needles and their resistance to technogenic and climatic stress in Scotch pine

Variation in the anatomical characters of needles and their resistance to technogenic and climatic stress in Scotch pine

Pinus uncinata Ramond taxonomy based on needle characters

11 needle characters of Pinus uncinata Ramond from the Spanish Pyrenees, P. mugo Turra from the Tatra Mountains, and P. sylvestris L. from N.E. Poland were analysed. It was shown that P. uncinata is much more closely related to P. mugo than to P. sylvestris. Nevertheless P. uncinata remains distinct from both in a number of the characters examined. The species differs from P. mugo especially in the length of the needles and in the distance between the vascular bundles. It differs from P. sylvestris in such characters as the number of resin canals, thickness of epidermis cells and the distance between the vascular bundles. Width of epidermis cells was similar in all taxa studied.

Phenotypic variation in cone and needle characters of Pinus banksiana (jack pine) in northwestern Ontario

To investigate the pattern of natural variation of jack pine (Pinus banksiana Lamb.), 64 natural stands from northwestern Ontario were compared based on phenotypic variation of cone and needle morphology. Cone and needle traits were determined for 10 trees from each stand. Vegetation and soil data for the stands were determined following the procedures established by the Ontario Ministry of Natural Resources Forest Ecosystem Classification program. Climatic data for each stand were interpolated using a geographic information system based on 1951 to 1980 data for Ontario and Minnesota weather stations. Nested analyses of variance indicated that most of the variation was expressed between trees and within trees, with relatively little (1.6 – 18.9% depending on the trait) expressed between sampled populations. Discriminant analysis of cone and needle data indicated that the 64 populations generally varied longitudinally with a steep cline in the Nipigon area (ca. 88°15′W) apparent for cone data. A corresponding irregularity in the pattern of needle variation suggested that the modern pattern may be the result of separate lineages, i.e., descendents from two migration routes along eastern and western shores of Lake Superior or from two refugia. However, temperature data follows a similar pattern in this area of Ontario, and multiple regression of the discriminant analysis score means for the 64 sampled populations against elevation, climatic, and soil data indicated that much of the cone and needle variation expressed between populations could be accounted for by the regressions. Thus, the observed patterns of phenotypic variation may simply be the result of local adaptations to a variable environment. Key words: jack pine, Pinus banksiana, phenotypic variation, cone traits, needle traits, northwestern Ontario.