Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research
Year:2016 | Volume:25 | Issue:1|Papers Count:21

Acer monospessulanum is an important species of the genus Acer from Aceraceae family. Turcamanicum subspecies spreads in Irano-Turanian region as associated plant of juniper forests in highlands of Razavi Khorasan province and northern part of the province. Its mast year is every three years, germination rate of seeds and number of healthy matured seeds is low. Also, the seeds have dormancy period and their germination percentage is decreased after chilling periods. Unfortunately, most of the species habitats are under intense grazing and human intervention effects, so that the species has been encountered with severe destruction. Due to sexual reproduction problems, application of vegetative propagation methods could be advantageous in high quality seedling production and reclamation of the habitats. One of seedling production methods is propagation using in vitro techniques. For this purpose, explants were collected from their natural habitats, and their regeneration was assessed in different hormonal treatments. Embryogenesis percentage in different hormonal treatments was investigated. Applying different hormonal treatments, callus regeneration was observed only in 0.1 and 0.5 mg/l of TDZ hormone concentration. Shoot number, shoot growth and shoot vigority were affected by different concentrations of TDZ hormones. MS media supplemented by 0.5 mg/l TDZ had the highest shoot production. But vigority and shoot length were not significantly different by utilizing different hormonal treatments. Finally, MS basal media and TDZ hormone are suitable for regeneration from callus in the valuable tree species.

Wild almond (Amygdalus scoparia Spach), is one of valuable almond species in Iran with medicinal and nutritional values as well as soil conservation and other environmental characteristics, which is also utilized as a rootstock in cultivation of domestic almond cultivars. After in vitro culturing of embryos of the species and enough shoot growth on DKW medium, with growth regulators such as IBA, BA and TDZ in 0.01, 0.5 and 0.05 mg.l-1 respectively, effects of light and growth regulators on rooting ability of the embryo driven shoots were investigated, using a factorial statistical model, based on a completely randomized design. Light as the first factor with 2 levels (a: 16 hours light and 8 hours darkness, b: permanent darkness for ten days) and growth regulators of DKW culturing medium as the second factor in 5 levels (1: NAA+IBA each for 1 mg.l-1, 2: NAA for 1 mg.l-1, 3: IBA for 1 mg.l-1, 4: IBA for 0.5 mg.l-1, 5: NAA for 0.5 1 mg.l-1) were used. Based on the results of analysis of variance, the two factors of light and growth regulator had significant effects on all of the studied characteristics. Light caused better growth of embryo grown shoots, compared to darkness. Various levels of growth regulators had also different effects on shoot and root production. Using a combination of IBA and NAA, produced the highest number of main roots. But 1mg. l-1 IBA caused the longest main root as well as higher number and length of lateral roots. Interaction effects between light and growth regulators significantly affected shoot length, main root length, number and length of lateral roots. So that combination of the two growth regulators produced the most number of lateral roots, whereas, utilizing 1 mg.l-1 NAA in darkness resulted in the most number of lateral roots. Results of analysis of variance indicated significant effects of light and culturing media factors on all of the studied characteristics. So that light caused remarkable increments on all of the studied characteristics. Various levels of applied growth regulators caused different effects on the studied characters. Meanwhile, IBA growth regulator caused significant increment of number and length of main and lateral roots. But NAA growth regulator showed significant effects on shoot length and number of leave. Interaction between light and media factors had significant effects on shoot length, main root length, number and length of lateral roots. Alternate light and darkness as well as IBA growth regulator are necessary for asexual propagation of wild almond through micropropagation.

Salvia leriifolia Bent. is a perennial herbaceous plant belongs to Lamiaceae family. Different pharmacological activities of the species were evaluated during recent years. Medicinal plant In vitro ploidy induction was one of the interesting issues in biotechnology and plant tissue culture. Therefore, influence of different colchicine concentrations (0, 0.05, 0.1, 0.2, and 0.5 %) in three time duration levels (24, 48 and 72 hours) on ploidy induction of in vitro regenerated seedlings of the species was studied. For detection of polyploid plants, morphological, physiochemical, biochemical and cytogeneticall characteristics were analyzed. ANOVA results revealed that, the effects of colchicine concentrations on explants survival rate were significant at p<0.01. Among the colchicine treatments the highest seedling survival rate (84.44%) was observed by 0.05% treatment. Although the most dead plants, were recorded in high colchicine concentration (0.5%). Induction of tetraploidy in Salvia Leriifolia accompanied by significant changes in different morphological, cytological, physiological and physiochemical characteristics such as, increasing length and width of stomata on leaf surface, leaf width, leaf area, leaf chlorophyll content, total antioxidant levels, total phenol and antioxidant enzyme activity (catalase and ascorbate peroxidase), as well as reducing density of stomata per unit leaf area and leaf length. Chromosome number of diploid plants was 2n=2x=22, and in tetraploid plants was 2n=4x=44. Therefore, colchicine effectively induces polyploidy in the species.

Populus species have distinct capabilities for which they are clearly differentiated. But the different capabilities made the species to be adapted to divergent climatic conditions. Interspecific hybrids between the species have inter-mediate capabilities for which they may extend ecologic distribution of the genus. Asexual propagation of three inter-specific hybrid genotypes between two poplar species, Populus alba and P. euphratica were propagated through micropropagation technique, in order to optimize aseptic asexual propagation of the hybrids as well as investigating possible differences between the genotypes in responding to the propagation method. The hybrids showed different responses to three culture media so that one of the hybrids, in contrast to other hybrids, even produced plenty of roots in proliferation phase. The mentioned hybrid was highly superior to others, based on the recorded characteristics such as stem number, stem length, bud number and root score. The hybrids were significantly different based on their responses to rooting culture media. The superior hybrid of proliferation phase, showed superiority in rooting phase as well. In case of selection of the superior hybrid as a commercial cultivar, it should be propagated by cutting, for which easiness of rooting may be its specific and noticeable character. Interaction effects between the two factors, hybrids and culture media, also revealed the superiority of the mentioned hybrid.

Effects of crown dieback intensity of Persian oak trees (Quercus brantii var. persica) on their leaf and branch physiological traits were monitored in drought affected Melah-Siah forest, Ilam province, Iran, during spring and summer seasons of 2013-2014. Oak trees were divided into 4 groups with 6 replicates based on the severity of crown dieback. Sampls were randomly taken on leaves and two-year old branches of oak trees in south aspect of tree crown. Several physiological traits including peroxidaz and catalaze enzymes, prolin, cholorophyll, carotenoid and leaf relative water content were studied. Results of crown dieback intensity effect on the studied traits showed that relative water content of declining trees was more than those of healthy trees. Prolin content of declining trees was more than those of healthy trees. Other studied traits did not show any significant changes among healthy and declining trees. Interaction effects of sampling year and season on the studied traits showed that branch peroxidase was at the highest level during spring 2014, lower during spring and summer 2013, and the least during summer 2014. Leaf catalaz was at the highest level during spring and summer 2013 and the least level during spring 2014. Branch catalaz was at the highest level during spring 2013 and at the lowest level during spring and summer 2014. Annual changes of cholorophyll b, total chlorophyll and RWC (from 2013 to 2014) were increasing, and for carotenoid, it was decreasing. Seasonal changes (from spring to summer) of cholorophyll a, carotenoid and RWC were positive, and for prolin, it was negative during the first year and positive during second year. It was concluded that variability of relative water content and prolin content in the declining trees was for stress reduction in tree body and transition from drought crisis, and non-significant changes of Photosynthetic pigments and enzymes is for continuing vital activities in its body.

Evaluation of performance was carried out in Satureja mutica Fisch & C.A, Mey and S.isophylla Rech, f. under dry farming using a 3 replicated randomized complete block design in Damavand, Iran. Significant differences were observed between the species for studied traits including plant dry weight, essence yield, canopy diameter, plant height, branch number and leaf length, with higher amounts for S.mutica. Also, accessions of S.mutica showed significant differences for essence yield, leaf width, leaf length, plant height and number of branches. Mean comparison indicated the highest essence content (3.86%) for one of the studied accession mu1Kh, the highest branch number for accession mu2Kh and the highest plant height and leaf length for accession mu3Gl. Also, significant positive correlations were observed between the traits, such as plant dry weight, with plant canopy diameter and branch number. Three components were resulted from principal components analysis, showing 95% of the total variation in which plant dry weight, essence content and plant canopy diameter were important, while in the second component leaf dimensions and in the third component, number of branches determined the most variation. According to cluster analysis, the accessions were classified into three groups. S. isophylla was located in a separate group. Also, accessions mu1Kh and mu2Kh of S.mutica were located in one group and accessions mu2Gl, mu3Gl and mu1Mz in another group. As a conclusion, mu1Kh of S. mutica could be proposed for cultivation under dry farming conditions in Damavand.

Bromus genus is one of the most important rangeland plants which have distributed in wide range of natural areas in our country. The interspecific relationship were evaluated in 45 diploid populations of two sections of Bromus and Genea, with 5 populations of Lolium multiflorum species based on karyotype characteristics. For each population five mitotic cells in metaphase stage were prepared from meristematic cells of root tips in newly germinated seeds. The total length, short arm and long arm length of chromosomes were measured. The centromer index, arm ratio, relative chromatin value, intrachromosomal and interchromosomal asymmetry index and total form percentage of chromosomes were calculated. The karyotypic asymmetry and types of chromosomes were determined. Variance analysis were showed a significant variation (P<0.01) between species and among populations. The populations had a symmetric karyotype which, were placed in A1 and A2 Stebbins’s classes and had a metacentric chromosomes and a few sub-metacentric chromosomes. The species of two sections were separated based on principal component and cluster analysis. The Karyotypic evolution for Bromus section was more from the chromatin value and for Genea section was further by increasing the asymmetry within and between chromosomes. B. briziformis Fisch. & C. A. Mey and B. squarrosus L. had the most karyotypic evolution and B. scoparius L. and B. danthoniae Trin. ex C. A. Mey. had the least karyotypic evolution in Bromus section. B. japonicus Thunb and B. rechingeri Melderis were placed between the two previous groups. B. tectorum L. were showed a karyotypic evolution more than B. sterilis L. and B. sericeus Drobow. in Genea section.

Foxglove plants are important sources of medicinal cardiac glycosides compounds such as digoxin and digitoxin, which are used for treatment of congestive heart failure and cardiac arrhythmia. Digitalis has several valuable species but the only species native to Iran is digitalis nervosa. Considering the importance of study on native plants in order to be used in pharmaceutical industry this research was carried out. One of the key genes in the biosynthesis of digitalis cardenolide in plants is3b-HSD, which encodes the enzyme 3b-HSD with important role in early stage of the cardenolide biosynthesis pathway. Purpose of the present study was to determine nucleotide sequence of 3b-HSD, phylogenetic analyses and its expression under influence of salicylic acid and methyl jasmonate elicitors in different tissues. Results revealed that a sequence encoding the enzyme show very close affinity to Digitalis lanata. In addition expression pattern of 3b-HSD in the transcript level revealed that a significant expression level was detected in leaf tissue, and also under treatment of methyl jasmonate and salicylic acid the expression level raised. Findings of our study could be used to increase cardenolide through metabolic engineering and genetic manipulation.

Genetic diversity among 16 accessions of Aegilops crassa was investigated using 10 ISSR primers. Totally, 105 alleles were amplified and 86 alleles (81.90%), were polymorphic. Number of amplified alleles ranged from 6 to 15 with average number of 11 alleles for each primer. Polymorphic information content (PIC) varied from 0.17 (primer UBC 842) to 0.34 (primer ISSR12). Marker index criterion ranged from 0.98 (primer UBC842) to 2.7 (primer ISSR08). Cluster and principal coordinate analysis could not completely separate accessions and showed no association between molecular diversity and geographic diversity of the genotypes, indicating that there is high genetic diversity among the accessions. Mean genetic similarity between microsatellite marker information was 0.89 ranged from 0.76 (between two genotypes from Kermanshah and Tabriz) to 0.96 (between two genotypes of Ilam and Kermanshah). Based on analysis of molecular variance, a larger proportion of genetic variation (53%) belonged to within populations, while a small proportion (47%) observed among the studied populations.

To investigate possible effects of seed source and genotypes on germination rate and several other morphological traits on seedlings of Acer monspessulanum subsp cinerasens, seeds were collected on 20 genotypes of two populations (2400 and 2700 meters above sea level) of the species of Chenarnaz forest, located in South part of Yazd province, Iran. Seeds were planted in a research greenhouse at Yazd University based on a completely randomized design with three replications. Analysis of variance showed that effect of altitudes of seed sources on collar diameter, root length and fresh weight of seedling root were statistically significant, so that, collar diameter and root length of seedling from the studied plant population at 2700 meters above sea level, were better than that of the second plant population. Although according to the studied characteristics of the population at altitude of 2700 meters the studied population was identified as a suitable plant population for seed collecting, seedling production, reforestation and subsequently recovery of degraded areas, but much less percentage of the stands at the altitude of 2400 meters could also be considered in order to maintain genetic diversity. Thus, on both plant populations, the best trees were identified in terms of the studied traits value. It is recommended that special attention be paid on the mentioned trees for seed collecting.

Golden germander (Teucrium polium L.) is an important medicinal plant of the Labiatae family. Genetic variability was studied on 17 ecotypes of Teucrium polium collected from Kermanshah, Iran, based on ISSR molecular markers. Twelve ISSR primers out of 15 primers could be scored. ISSR primers produced 82 bands, of which polymorphism was observed on 80 bands. Average number of bands was 6.83 for each primer. Primer IS6 showed the highest number of bands (12 bands) and IS3 showed the lowest number of bands (4 bands). The results indicated that ecotype G1 had the most genetic distance with G12, G7, G13 and G8. Based on cluster analysis the ecotypes were grouped into four clusters. Genetic diversity of ecotypes did not match with the geographical diversity of the ecotypes. Also results of grouping by analysis of molecular variance (AMOVA) and coordinate analysis (PCo) were confirmed.

Camel thorn (Alhagi camelorum F.), a plant from Fabaceae family, has a great adaptation in arid conditions. Due to high digestible proteins, possibility of extracting manna from its stems for medicinal purposes and its high tolerance to harsh arid environments, it is considered as an important forage and medicinal plant. It grows via seed and rhizome, but its seed germination rate is very low. Aim of the research was to investigation possible effects of different sucrose concentration levels in micro- propagation of the species via ovary and seed embryo culture to improve its propagation. Seed germination of the species was tested by two explant treatments of ovary and seed embryo in 5 sucrose levels of 0, 15, 30, 45 and 60 gr/l concentrations in MS medium in 5 replications. Germination rate was recorded during four weeks. Results of comparison of germination rates between the two explant treatments in different sucrose concentrations showed that the percentage of embryo germination and seedling height was significantly higher than that of ovary culture. The highest significant embryo germination rate (93.3%) was recorded on 15 gr/l sucrose concentration. By increment of sucrose concentration to 15 gr/l, embryo attributes such as radicle length, plumule length, seedling length, and seed germination index also increased. By increasing sucrose concentration over 15 gr/l, reverse effect was observed on all of the studied attributes.

Thymus vulgarisis one of the most important medicinal plants with more than 20 types of known important chemical compositions. A gene named 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) acts as an important control point, as this is the first committed step in the MEP pathway. g- terpinene is a key component in essential oil of thyme which constituted up to 30% of the essential oil in the species and is biosynthesized via g- terpinene as a penultimate precursor. Different cytochrome P450 including CYP71D178 and CYP71D182 are involved in the biosynthesis of thymol and carvacrol in thyme and oregano via the g- terpinene as an intermediate. The aim of the present work was to study the expression patterns of genes involved in thymol and carvacrol biosynthesis including DXR, g- terpinene synthase, CYP71D178 and CYP71D180 genes in flowers and leaves of thyme. Gene expression analysis of DXR, g- terpinene synthase, CYP71D178 and CYP71D180 genes were carried out by semi-quantitative RT-PCR technique. The relative gene expression of flowers compared with leaves for DXR, g- terpinene synthase, CYP71D178 and CYP71D180 genes were 1.7, 2.7, 1.9 and 2 fold higher, respectively and the gene expression intensity varied for each gene. Expression of aforementioned genes in glandular trichomes were high, hence the higher gene expression in flowers might be related to higher density of glandular trichomes. Based on these results, higher content of essential oils in flowers compared to leaves is most likely further related to the higher expression of related genes in flowers rather than leaves.

To examine morphological variability of leaves and fruits of wild pear (Pyrus glabra) among different populations, leaf and fruit samples of 48 trees from four populations at altitude of 2150 m above sea level (Tange Sorkh), 2250 m (Vezg), 2450 m (Gorgo) and 2550 m (Mahparviz) located in Boyer Ahmad city, Iran, were collected. Then, 16 quantitative and qualitative leaf and fruit morphologic traits were recorded. Analysis of variance showed that among the studied parameters, lamina length, petiole length, lamina width at 0.1 and 0.9 of leaf lengths, maximum width of lamina, relative length of petiole, leaf shape, small and large diameter of fruit showed significant differences among the populations. Results of principal components analysis showed traits such as maximum width of lamina, lamina length, leaf dry weight, leaf tip angle, and leaf specific surface, played the most important role in grouping the genotypes and populations. In addition, leaf tip angle, leaf dry weight, and leaf surface had the highest coefficient of variation. Results of discriminate analysis showed that effective traits in isolation of the populations including leaf shape and fruit large diameter. Finally, leaf base shape, and large diameter of fruit remained unchanged resisting environmental changes (less variability) can be used as good traits to identify and separate genotypes of wild pear.