Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research
Year:2003 | Volume:11 | Issue:2|Papers Count:11

In order to determine in vitro regeneration potential of date palm (Phoneix dactylifera L. cv. Mazafati), isolated embryos from immature fruits were transferred to hormone free half-concentration MS medium and MS containing growth regulator hormone. To stimulate meristemic cells for adventitious bud initiation, isolated explants in 1 to 3 cm height were vertically cultured on MS medium containing 0.4 mg/l thiamine Hcl, 100 mg/l inositol 30 g/l sucrose and different combination of growth regulators. MS medium containing 10 mg/1 of 2ip produces highest percentage of bud development and shoot growth.Adding MS hormone free liquid medium on surface of establishment medium with initiated bud was caused in vitro shoot elongation. Elongated shoots was used for shoot proliferation by permanent cutting of shoot in collar and transferring of them to rooting or shoot elongation media. Highest root induction was observed in MS medium supplemented with 10 mg/l 2iP and 0.01 mg/l IAA (more than 80%).

In order to examine and evaluate the variation and process of deterioration of accessions of Onobrychis saliva seeds, which have been collected and maintained in natural resources genebank, a research project were carried out using 9 accessions. All of the accessions were examined in a complete randomized design with three replications under using germinator and glasshouse conditions.The recorded traits of the Germinator test were included, germination percentage (G.P.), speed of germination and vigor. The recorded traits in glasshouse included G.P., speed of germination, plant height, number of tillers and root length in 40 days after planting.The results showed significant difference between accessions for all of traits. Variation between accessions was significant in one or both of the environments.The results of correlation coefficient study shown that Speed of germination, could be very good indicator of seed vigor. This result was confirmed by regression model. Negative correlation was found between reduction of G.P., speed of germination and seed vigor in germinator condition and G.P., speed of germination, plant height, number of tiller and root length in glasshouse condition. Therefore, seed deterioration not only reduces G.P, but also decreases the speed of germination and seed vigor. In all of the Onobrychis saliva accessions, because stored samples of each year were different from other years therefore, reduction of G.P., was highly affected by origin of accessions. It was not possible to differentiate between the effect of maintaining condition and origin of seed. It was suggested that, for better genebank management, accessions, have to be considered as regeneration unites of collected seeds

In order to study the genetic variation of wild service (Sorbus formina/is) in Sangdeh forest of Mazandaran province, 40 indivisual trees from 2 populations were selected. From the crown of each tree, 60 fruits were by random scatered. Seven morphology and quantitical traits of the fruits and seed of these trees were studied. Data were analyzed using principal component and cluster analysis. The first two components determined 81.48% of the total variation in principal component analysis. The large diameter and the small diameter of fruits were the most important traits to make the first component. The small diameter and number of seed of the fruits were the most important traits, to make the second component. The trees were grouped into 8 cluster based on multivariate analysis of 7 classification variables. Distribution of tree based on the first two component scores was in agreement with cluster analysis. According to the results of clustering analysis and ploting of two first components, the most genetic variation observed between two populations. It was in agreement with the result of isoenzyme electrophoresis technique study, with which these two population and theirs trees were examined.

Rosa damascena was collected from three parts of Kashan, and cultivated at the experimental field of Research Institute of Forests and Rangelands, using a three replicated randomized complete blocks design. Nine genotypes were compared based on 4 different traits including petal, stamen, and pistil number and essential oil concentration, in 2002. Data were collected and analyzed using ANOVA, mean classification and cluster analysis. Genotypes showed significant differences in terms of the measured traits. Comparison of means classified the genotypes in 2, 3 and 2 groups, for petal, stamen and pistil number, respectively. Also, essential oil concentration showed a considerable genotypic variation. The areas showed significant differences in petal and pistil number. Cluster analysis classified the genotypes in two groups, based on the traits under study. The results indicated that there is not a good relationship between variation of the genotypes and geographical location. However, a considerable variation was revealed in floral parts and essential oil concentration of Rosa damascena from Kashan.

The purpose of this research was to study the genetic diversity, broad sense heritability (h2 B), linear correlations of the characters under study and multiple correlation coefficient several character with forage dry yield in Elymus tauri. The experimental material included the 8 landrace populations of E.tauri belonging to East Azarbijan and Ardabil provinces. The experiment was conducted as randomized complete block design with four replications in the Botanic Garden of Tabriz in autumn 1997.In analysis of variance there were significant differences among the populations including the number of fertile tillers, number of total tillers, spike length and leaf length. Broad sense heritability estimates were moderate to high as 83%, 72%, 80%, 61% for number of fertile tillers, number of totale tillers, spike length and leaf length, respectively. Ward's cluster analysis of 8 E.tauri populations resulted two cluster groups. It was found that genetic diversity correspond sampled with the altitude of the regions from which the populations of the traits under study only the leaf length showed significant linear correlation with forage dry yield. However multiple correlation coefficient of dry yield with all other morphologic traits were high (R=0.8%).

For evaluation of seed quality traits (germination percent, rate of germination and vigor index) in Moldavian balm (Dracocephalum moldavica L.) an experiment was conducted using accelerated aging test (AAT) under laboratory condition. The seed samples were subjected to 40°C in 100% relative humidity for 0, 12, 24, 48 and 72 hours. A completely randomized design with 3 replications was used. The results showed significant differences among treatments for germination percent, rate of germination and vigor index. There were no significant differences between 0, 12 and 24 hours AAT treatments for germination percent and rate of germination, but AAT treatments for 48 and 72 hours significantly decreased germination percent and rate of germination compare to 0, 12 and 24 hours. Increasing the time of AAT treatments decreased all of the three seed quality characters. The vigor index was affected more than the two other quality characters. The effect of AAT duration treatments on vigor index reduction was as fallow: 0 > 18, 24 > 48, 72. It is concluded that under conditions of this experiment, the vigor index is more sensitive trait for seed quality evaluation of moldavian balm (Deracocephalum moldavica L.) seeds.

Cozal (Diplotaenia damavandica) is an important native medicinal plant in Iran. Because of its active metabolite compounds such as Xanthotoxin and Angelhcin it is used for dermatical disorders. An effort to seed germination of this species has not been successful so far.In this experiment, following surface sterilization of seeds whit ethanol (75% for 5 sec.) and Sodium hypochlorit (1% for 15-0 min.), the following treatments was carried out: 1- Stratification (I-3oC) for 15, 30 and 45 days in sand and filter paper.2- Application of gibberellic acid (GA3) at three concentrations (50, 100 and 200ppm).3- Scarification with sulfuric acid (10 and 20%) at 10 and 20 minutes. The results showed that stratification on sand for 45 days is the best treatment to overcome seed dormancy. Application of gibberellic acid (GA3) at 200ppm caused seed germination, but seedlings didn't establish in the condition. Sulfuric acid was not effective in braking dormancy of seeds.