Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research
Year:2011 | Volume:19 | Issue:1 (37)|Papers Count:16

Random amplified polymorphic DNA (RAPD) markers was used to characterize genetic diversity among 16 ecotypes of Iranian Echium amoenum collected from western and northern regions of Iran. Total genomic DNA was extracted by STE method and polymerase chain reaction (PCR) was performed using twenty three RAPD primers. From 438 scoreable bands, three hundred and eighty five bands among different ecotypes were polymorphic (87.9%). RAPD products were scored for presence (1) or absence (0) of each amplicon. Binary method and subsequently genetic similarity was calculated by employing Dice index. Cluster analysis was carried out according to UPGMA algorithm. Cluster analysis, classified ecotypes into eight main groups. The highest similarity (0.68) was found between Gazvin and Lorestan ecotypes, whereas, the lowest was between Gannat Roudbar and Gorgan. The results showed there was a moderate level of genetic diversity among Echium amoenum ecotypes. Moreover, results indicated that RAPD technique is an efficient tool for assessing genetic diversity in Iranian Echium amoenum ecotypes.

Biomass production, shoot, root, leaf, root to shoot ratio (R/S), specific leaf area (SLA) and water use efficiency (WUE) of eucalyptus (Eucalyptus camaldulensis Dehnh) were investigated under three different soil water regimes, 100%, 70% and 40% of field capacity (FC). The research was conducted based on a complete randomized design with 3 replications under lysimetery and natural conditions in an arid region. The experiment was carried out during 2006-2008 at Shahid Sadouqi Desert Research station of Yazd. Results showed that biomass production, shoot, root, leaf, root to shoot ratio and shoot to life ratio decreased significantly with reduction in soil water content. Specific leaf area increased significantly with reduction of soil water content. Water use efficiency increased significantly with reduction of soil water content but was not significant between 70% and 40% field capacity treatments. Regarding wood production, water use efficiency increased significantly for 70% field capacity treatment, compared to other treatment.

Galbanum (Ferula gummosa) is one of the native valuable pasturage-medicinal plants of Iran that is extincting because of irregular and unsuitable harvesting from natural habitats and its propagation problems. Results showed possible conservation of galbanum germplasm under in vitro culture conditions on MS medium supplemented with 2 mg l-1 BA at 25±2oC under a 16-h photoperiod for about 5 months. Petiols obtained of cultured in vivo plants under in vitro conditions, are capable explants for callus production and they produced callus with high quality and quantity on B5 medium supplemented with 2 mg l-1 BA and 10 mg l-1 NAA.

Forage quality components of 47 alfalfa ecotypes were studied using near infrared reflectance spectroscopy (NIRS). Results of correlation coefficient among the studied traits showed that dry matter digestibility (DMD) had a positive significant correlation with crude protein (CP) (0.67), and a negative significant one with crude fiber (CF) (-0.51) and acid detergent fiber (ADF) (-0.96). However, correlation between CP and CF (-0.60) and ADF (-0.52) was significantly negative, A positive significant correlation was estimated between CF and ADF (0.37). Result of regression analysis showed that CF and WSC justified 63.5% and 7% of the total variation in ash content, respectively. Hence carbohydrates are the most important variables in determination of total ash content. For evaluating of Mahalanobis distance, the ecotypes were classified into five groups according to their geographical locations and the results illustrated a high distance between the western ecotypes and the others. However, a similarity between the central ecotypes (Esfahan and Chaharmahalo Bakhtiari) and the eastern one (Khorasan, Golestan and Semnan) was clarified. By principal components analysis, DMD, CP, ADF and metabolism energy (ME) were introduced as the most important indicators in forage quality. A Depicted Bi-Plot based on PC1 and PC2, elucidated a high dispersal and diversity among ecotypes and indicated the appropriate ecotypes for utilizing in breeding programs. Cluster analysis using Between-Group Linkage method was performed and depicted dendrogram illustrated a high diversity in forage quality components in ecotypes even those collected from one province. As a whole, the results showed that there is a high potential for selection of desirable parents and usage of heterosis in breeding programs. The results of correlation between the traits could be used for the selection of plants with good quality traits.

Genetic diversity of many important traits has been limited in primary gene-pool of crop species causing vulnerability. Six-rowed barleys have a narrow genetic base. Ancestral species are important resources of new alleles for germplasm enhancement. Thirty five accessions of Hordeum spontaneum selected from barley collection of National Plant Gene-bank of Iran were evaluated during 3 years for agro-morphological traits. Auricle and stem pigmentation were the most variant of all qualitative traits based on Shannon index. Estimates of coefficient of variation for potential grain and forage yield were relatively high indicating the potential of the studied accessions of H. spontaneum for exploitation of genetic diversity. The first three principal components comprised 71.24% of the total variation of the data. The first principal component emphasized on higher yield, vigor and early maturity and second principal component indicated higher yield, vigor, and late maturity. Traits of grain yield, 100-kernel weight, days to head emergence, biological yield, and awn length had high broad-sense heritability from 73.78 to 80.44%, hence breeding for these traits would be of high efficiency. The results of cluster analysis based on the origin of accessions were in agreement with their geographical pattern.

Lonicera nummulariifolia Jaub. & Spach, is a deciduous shrub growing in Zagros region of Iran as a companion species with oak, especially in Sepidan county, Fars Province, Iran. However, there isn't enough information about its propagation and different aspects of its growth. This study was carried out to develop in vitro culture techniques for rapid and mass propagation of the species. Shoot tips and nodal segments of seedlings were used as explants. Murashige and Skoog (MS) medium containing 0.1 mgl-1 BA was optimum for shoot multiplication. Nodal segments cultured on Driver and Kuniyuki walnut (DKW) medium containing 0.4, 0.7 and 1.0 mgl-1 BA, 30 gl-1 sucrose and solidified with 8.0 gl-1 Difco Bacto agar in comparison with MS medium didn't show any significant differences on measured growth indices. The best procedure for in vitro rooting consisted of two phases: root induction and root development. For root induction the most efficient method was utilization of MS medium (half strength macronutrients) solidified with 8.0 gl-1 Difco Bacto agar, containing 30 gl-1 sucrose and 25.0 mgl-1 IBA in dark conditions for 60 hours. For root development, shoots were transferred from root induction medium to hormone free medium in lighted conditions. Using this method, about 46.7 percent of the shoots rooted. After root development, plantlets were transferred to pots containing a mixture of peat, sand and vermiculite (1:1:1) and transferred to greenhouse.

Genetic diversity in eighteen Iranian populations of desert wheatgrass (Agropyron desertorum), was evaluated using morphological traits and Randomly Amplified Polymorphic DNA (RAPD) markers. The populations were examined for seed yield and its components using a complete block design with 3 replications as spaced plant under irrigation conditions during 2006-2008. Analysis of variance showed significant differences among the populations for all the studied traits. The population 400 (Ardabil) had higher dry matter (9.24 ton/ha) and seed production (514.89 kg/ha). Broad-sense heritability values were high (h2b= 0.52-0.61) for seed yield, spike length and seed number per spike. For stems number broad-sense heritability was moderate (h2b=0.27) and for other traits it was low and non significant. Ten primers out of the 50 decamer random primers screened generated 56 highly repeatable polymorphic bands. Estimates of Nei's gene diversity (h) and Shannon's Information index (I) for all loci in individual populations showed the populations of 3974 (Karaj) and 742 (Hamedan) had higher (h=0.302 and I=0.449) and lower (h=0.146 and I=0.225) gene diversity, respectively. Total gene diversity (Ht) and mean of gene diversity within populations (Hs) were estimated 0.224 and 0.356, respectively. Average value of gene diversity among the populations (Gst) was estimated as 0.37. The results showed that of total variation, between and within population variation were 0.37 and 0.63, respectively. Jaccard's similarity coefficients ranged from 0.19 to 0.49 across all 18 populations. The molecular and morphological data were subjected to Unweighted pair group method with arithmetic averages cluster analysis, Populations were partitioned into three groups. In both cluster analysis, population of 400 (Ardabil) was located into same separate group. The Mantel correlation analysis between morphological and RAPD data was not significant. In general, RAPD markers data proved to be a good method of assessing genetic variation among populations of desert wheatgrass.

In order to study drought tolerance indices and to identify drought tolerant genotypes, 75 genotype of tall fescue (Festuca arundinace) (25 early maturity, 25 late maturity and 25 parental genotypes) were evaluated under moisture stress and non-stress field environments using a randomized complete block design for each environment in the research farm of Isfahan University of Technology, Isfahan, Iran. Five drought tolerance indices including mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), stress susceptibility index (SSI), and tolerance index (TOL) were calculated. Analysis of variance for each maturity group showed that there was a significant genetic variation among genotypes for all criteria. Correlation analysis showed that MP, GMP and STI had significant and positive correlation coefficient with yield under both stress and non stress conditions, suggesting that these indices are more efficient in determining drought tolerant genotypes. Based on multivariate biplot on all indices and triple plot on the two most important indices (STI and GMP) similar genotypes were indentified as the most tolerant genotypes in low irrigation condition. These were genotypes number 21 and 23 in parental group, numbers 10 and 23 in early maturing group and 3, 5 and 13 in late maturing group. Classification of genotypes using cluster analysis based on the three indices of MP, GMP and STI confirmed the results of biplot and triple plot for identifying tolerant genotypes.

The research was carried out to study biodiversity aspects of six small burnet populations, using cytogenetic traits. Root tips were stained; and chromosom morphological traits such as short arm length (SA), long arm length (LA) and total length (TL) were measured using photomicroscope and Micromeasure software. Analysis of variances was performed on chromosomes morphological traits: LA, SA, TL, arm ratio (AR) and centromer index (CI), using unbalanced completely randomized design with at least three replications. Several symmetrical assessment statistics such as: relative length of the shortest chromosome (S%), total form percentage (TF%), A1, difference of relative length range (DRL), A2, Levans chromosomal nomenclature method and Stebbins categories (SC) were calculated. Results showed that populations number 10462, 13976 and kangalchal populations were tetraploid (2n=4x=28) while population number 12333 was hexaploid (2n=6x=42), and populations number 13963 and 13296 were octaploid (2n=8x=56). Populations 13296 (octaploid) and 13976 (tetraploid) showed the most asymmetric karyotype between the studied populations base on A2 and DRL. Populations 13963 (octaploid) and 13976 (tetraploid) showed the most asymmetric karyotype between all of the studied populations base on %TF and A1. Using principal components analysis, the first three components justified % 99.7 of the total variance. In the first component, SA and TL with the highest coefficients of eigen vectors, were the most important traits. In the second component, LA, AR, CI, %TF and A1 had the most important role. In the third component, %S, DRL and A2 were the most important traits. Cluster Analysis classified the population in three clusters when clustering was performed based on karyotypic statistics. Clustering revieled that the octoploid population, 13296 had the most genetic distance with 13976 octaploid papulations. According to the scater plot, base on the first two components, the populations were grouped in three distinct classes, corresponding with the result of cluster analysis.

The research was conducted to investigate genotype × environment interaction for forage yield of 25 tall fescue genotypes at seven environments (combinations of years and locations). Analysis of additive main effects (analysis of variance) and multiplicative interaction effects (principal components analysis) revealed that the effects of genotype, environment, and genotype × environment interaction were highly significant. The first three principal components explained 89% of the total variation. Biplot of the first principal component and mean forage yields for genotypes and environments revealed genotype numbers 8 and 20 as the most stable and high yielding genotypes. The genotype numbers 1, 12, and 14 were detected in the second rank of stability and high yielding. Pattern analysis of the two first significant principal components for genotypes and environments and also cluster analysis based on stability statistics of AMMI3 model (SIPC3 and EV3) showed that genotype number 8 had general stability. Yield of the genotype was higher than average of all of the studied genotypes indicating general adaptability. Genotype numbers 1, 9, and 12 had medium to low stability. Genotype numbers 10, 13, 19, and 25 were recognized as unstable ones. Genotypes of 2, 16 and 17 can be nominated as genotypes with narrow adaption to environments with sufficient irrigation (years of 87 and 88, Isfahan site) and genotype number 18 as genotype with narrow adaption to defficient irrigation condition (years of 86 and 87, Lavark site). All the environments contributed to the interaction effects and defficient irrigation has intensely affected the genotype yields.

Iris is one the major ornamental and pharmaceutical plant species from Iridaceae family. It is also native plant of Iran, which has special economic position in the world. In order to determine genetic variation and heritability on several traits, 18 Iris species were collected from different habitats of Iran. The materials were studied at the National Ornamental Plants Research Station based on a randomized complete block design with three replications. Statistical parameters, including correlation coefficients, broad sense heritability, phenotypic and genotypic coefficient of variation were estimated. Analysis of variance showed significant differences between the species for all of the studied traits (a=0.01), indicating wide variation for the studied traits in the wild species. The highest phenotypic and genotypic coefficient of variation were observed on periant tube length, 70%, inner tepal width, 74%, and plant height, (69 and 67%). I. Germanica (F1) species in the most of the studied traits was superior. The strongest broad sense heritability was related to inner tepal width (98.95), outer tepal width (98.74), outer tepal width of claw (98.67) and inner tepal length (97.78). The most positive and significant correlation coefficients was observed between Inner tepal length and inner tepal width. Whereas, the lowest correlation value was observed between perianth tube length and pistil width.

In order to evaluate genetic variation and relationship among characteristics of 12 genotypes of Foeniculum vulgare, an experiment was conducted based on randomized complete block design with 3 replications at Fozveh station, Isfahan, Iran. Analysis of variance showed significant differences among the genotypes for the studied traits. Broad- sense heritability was middle to high (48-99%) for all of the traits except number of umbel and flower in umbel. Correlation coefficients showed that seed yield had a positive correlation with days to ripening, number of umblet and essential oil percentage. Using principal components analysis, the first four components determined 85% of the total variation. Number of branches and sterile flowers, seed yield (kg/ha), days to 50% and 100% flowering, days to ripening and height at 50% flowering date were the most important traits in the first component. Height at 100% flowering date, dry weight/fresh weight ratio, essential oil and ash percentage in the second component, number of umblet and number of flower in umblet in the third component and number of branches in the forth component were important. Genotypes were classified into 3 groups with distinct variations for seed yield, essential oil percentage, day to ripening and plant height. Thus, crossing plants from genetically diverse genotypes may result in superior cultivar development.

Allelopathic compounds influence biochemical and physiological processes of their adjacent plants. Artimisia herba alba is a shrub and perennial plant which has widely distributed in Iran rangelands Allelopathy effects of different concentratins of essentioal oils of the species on germination percentage, speed germination and growth parameters (root and shoot lenght, fresh and dry weight) of Medicago sativa and Onobrychis sativa were studied. The concentrations were 100, 300, 500 and 700 ppm compared with distilled water as control treatment. ED50 and ED90 values were calculated using dose response curves for Not-germinated (probit scale) against essential oil concentration (log scale). Results showed significant differences between the treatments on root length and vigor index at 0.01 probability level, shoot length, and fresh weight at 0.05 probability level. The treatment level of 700 ppm showed the lowest root length, fresh weight and vigor index. Thirty two combinations were identified by gas chromatography in which cis-pinocarveol and artemisia ketone showed the highest level. Increment of the essential oil concentrations decreased seedling growth parameters and germination percentage in Medicago sativa and Onobrychis sativa. It seems cis –pinocarveol as terpens composition and artemisia ketone, trans-sabinene hydrate, 1, 8-cineole and Myrcene as monoterpene compositions, that constituted a high percentage of the essential oil of the species, have a major role in the development of allelopathic effects of Artimisia herba alba.

Cerasus mahaleb is one of the important species of Rosaceae family in Zagros forests. It is used as root stock for sour and sweet cherries. It is also used for gardens decoration. Environmental effects of Cerasus mahaleb is erosion control and shelter pattern. Cerasus mahaleb has long term dormancy. Therefore, removing the dormancy of the species seeds by laboratory methods, would increase its germination rate which is an effective method of improving its establishment and reclamation. Seed collection was performed at Galal site of Paveh, located north-west of Kermanshah, Iran, on 1200-1300 altitude by a random method. The experiment was carried out based on a completely randomized design with 8 treatments and 24 replications. Treatments were: control, GA3 in 200, 500, and 1000 ppm concentrations on seeds with and without coat. Results showed that there were significant differences among concentrations of GA3 on seeds with and without coat. Also the results showed that maximum germination happened on seeds without coat in 1000 ppm and minimum germination happened on control, 200, 500 and 1000 ppm on seeds with coat. Maximum germination speed was observed on seeds without coat and maximum germination duration was observed on seeds with coat.