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We studied the variation in leaf morphological traits for 7 habitats of Populus euphratica Oliv. in natural form as well as transplanted to an experimental station in Karadj- Iran. In this study, 28 even-aged, mature P. euphratica trees and 24 leaf samples were randomly collected from each habitat (6 leaves for each tree). Then a set of macro- and micro-morphological characteristics were measured on the samples. There was a plastic morphological response to the environment for each provenance. All morphological characters except maximum leaf width (MLW), ratio of petiole length to leaf length (PL: LL) and the distance between the middle of maximum leaf width and leaf blade (DLL) varied significantly among provenances in both natural and field conditions. Stomata density and stomata size were plastic characters, since the stomata density increased in warm habitats while stomata size decreased. In addition, we observed significant differences in size and density of stomata for natural and field-transplanted provenances. Correlation analysis between environmental factors and leaf morphological traits indicated a significant relationship. Furthermore, Principal component analysis (PCA) on all morphological traits on provenances showed that morphological range of the provenances decreases when growing in the experimental field compared to their natural habitat. Eventually, we found a weak significant correlation between geographical and morphological distances.

Fagus is one of the most abundant and economically important forest tree genera in north of Iran. 14 populations of F. orientalis Lipsky were selected from its wide distribution through the Caspian Forests, in order to study the species genetic variation by three methods: enzyme, cpDNA and morphology. Chloroplast (cp) DNA polymorphysm was analyzed in the same populations of the Iranian beech by PCR-RFLP test. Two cpDNA gene regions, including DT and OA were generated and digested by bounder of HaeIII and HinfI. endonucleases The generated pieces fragments were separated by gel electrophoresis. The digestied profiles of the two regions CDT and OA were compared simultaneously with the digestied fragments of the control DNA of the known haplotype (kindly provided by Raffaello Giannini, IMGPF-CNR, Italy) to identify the Iranian haplotypes. The restricted fragments of the region DT did not show polymorphism among the individuals within any analysed population. However, among individuals within the analysed populations of Asalem and Neka-1400 areas, polymorphism in the bounder fragments of the OA region was found. Overall, three different chloroplast (cp) haplotypes were scored. Distribution of the cpDNA haplotypes revealed a geographical structure of the genetic differentiation with Gst=%68.7 and Nst=%70.3.

Low germination and non-viability of embryos are the main hindrans for forestation of Juniperus excelsa. Conventional methods of asexual plant propagation of this species have not been successful so far. In order to in vitro propagation, small pieces of stem of 8-10 years old trees(10-15 mm long) containing shoot tips with needles fascicles were used as explants. Those were excised from the plants and after surface sterilization. Samples were cultured on a Murashige & Skoog (MS) medium and six revised MS medium supplemented with different concentrations of BAP, Kin, IBA, NAA and 2,4-D. Then the cultures were incubated in a climate chamber at temperatures of 25°C (for day) and 15°C (for night) and 12 hours light at 2000-2500 Lux with 75% humidity. Results indicated that callugenesis and callus growth restricted by both type and nitrate and hormonal source. The best simulation of callus growth occurred on cultures of without KNO3, with gloutamin (100 ml/l) and amount of 2,4-D/BAP at more than 1 ratio. Although adventitious buds were formed on juvenile stages of parent plants, but root induction did not occur. In addition, the season of sampling can also restrict the calogenesis. Such, calougenesis of collected plants in autumn was more than in spring. We could not find any shoot proliferation on medium MS, however by elimination of ammonium nitrate from medium MS bud appeared from callus as well as leaf blade.

In this study, role of total proteins, peroxidases and polyphenoloxidases in metabolisms of juniper were studied. For this purpose, seasonal alteration (quantitative and qualitative) of total proteins, peroxidases and polyphenoloxidases from branches, leaves, male cone and bery were analysed by electrophoresis and spectrophotometric methods in male, female and male-female plants. Results indicated that in spite of specific differences in each stand, activity pattern of enzymes were similar. The highest activity of peroxidases from leaves and branches were seen in spring and autumn and the lowest activity were in summer and winter. Protein, peroxidases and polyphenoloxidases rates of male cone decreased in winter. Comparision of peroxidases with polyphenoloxidases activity during female maturity indicated that maximum activity of polyphenoloxidases was in the first stage growth and minimum activity of peroxidase was in second stage growth. This results indicated this enzymes involves in juniper metabolismes such as, growth and development, photosynthesis, hormonal balance, organogenesis, morphogenesis and resistance to environmental conditions.

Chloroplast (cp) DNA polymorphism was analyzed in 14 populations of beech (Fagus orientalis Lipsky) by PCR-RFLP and microsatellite (SSR) chloroplast markers. Two cpDNA inter genic regions DT and OA were amplified and treated with HaeIII and HinfI, respectively. The restriction fragments of the region DT did not show polymorphism among individuals within any population analyzed. However, among individuals within the analyzed populations of Asalem region and Neka-1400 population, polymorphism in the restriction fragments of the OA region was found. Three haplotypes, which could be phylogenetically ordered, were detected in this survey encompassing most of the natural range of the species. The high level of genetic differentiation (Gst=%69) together with the highly structured geographic variation contrast with low level of nuclear genetic differentiation measured in previous studies with isozymes and indicate a low level of gene flow by seeds. Among nine analyzed microsatellites, two showed polymorphism. Two and six different length variants at ccmp4 and ccmp7 loci were found, respectively, which combined into 10 different haplotypes. The distribution of haplotypes showed a very strong differentiation among populations (Fst=80%) and clear geographic structure. The analysis of molecular variance (AMOVA) showed that 52, 28 and 20% of the total cpSSR variation was attributable to differences among regions, among populations within regions and within populations, respectively. Clear evidence has been obtained that geographical distance is a major factor of population differentiation in the beech. This long-range pattern of variation was partially expected, given the huge natural range of beech and the existence of a gradient of variation in ecological factors. The high haplotype richness in the western populations, which found by the both markers in this investigation, is in accordance with this hypothesis that the beech forests of the Hyrcanian regions distributed from West to East.

Beech is one of the most abundant economically important species in northern Iran. Stand structure identification, combined with silvicultural characteristics, including of ad-mixture, age classes, vertical and horizontal structure, crown cover, absence or presence of gaps and regeneration or under storey could help in optimal management. Morphological qualitative and quantitative characteristics as well as genetic variation of beech were investigated in 14 sample plots, each covering 0.5 ha; originating from the major part of distribution range of this species in Hyrcanian zone. In this research also the role of human manipulation and selected management methods for management of beech forests on these characteristics were studied. Considerable genetic diversity of beech forests (expected heterozygosity = 0.191) represents large adaptive potential of this species. Due to positive correlation between genetic diversity and rate of undesirable trees, selection and conservation of desirable trees in shelterwood system must be considered with precautious. Because the selection for conservation of some genotypes is one of the most important processes in forest management practices, it changes the genetic variation of trees. During this process frequency of some genes and following that genetic variability and future adaptability, would be strongly reduced. An appropriate silvicultural system should reflect a sense of conservation, or a determined effort to provide future yields of goods and other values, even while harvesting or using those available at the moment. Therefore, the rate and circumstances of utilizing resources at present would be guaranteed adequate and continuous applies for future. Recent studies revealed that among silvicultural methods, the selection system and group selections are the best options for management of beech forests in a sustainable way. In this research high adaptive potential of some population (Neka at elevation 900 m.a.s.l. and Kheyrud at elevation 600 m.a.s.l. with 14 rare and specific area alleles) in comparison with limited adaptivity of others (such as Kheirud at elevation 1200 m.a.s.l. and Gorgan at elevation 2000 m.a.s.l. with 2 rare and specific area alleles) also emphasized on genetic resource conservation of beech forests and selection of suitable silviculture methods based on potential in every region.