Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research
Year:2015 | Volume:23 | Issue:2|Papers Count:16

In order to evaluate genetic diversity of 22 cultivated sainfoin accessions collected from different regions of the world, SSR markers from Medicago genus were used. Polymorphism information content value ranged from 0.20 to 0.43 with an average of 0.33. The most informative markers were “mtgsp_005e04.taa.9-1” and “Actt004” with the highest polymorphism information content values. Cluster analysis based on SSR markers grouped the sainfoin populations into two main groups (Iranian and exotic cultivate sainfoin) with two subclusters for each group. The two sub-clusters of exotic group (B) mostly comprised accessions from Western Europe (BI) and Central and Eastern Europe (BII). The clustering results were also confirmed by principal coordinate analysis. According to the analysis of molecular variance, 13.6% of genetic variation related to among Iranian and exotic cultivated populations and 69.5% related to within-population diversity in the sainfoin populations. The analysis of molecular variance also indicated a fixation index of 0.27 suggesting a high differentiation among Iranian and exotic cultivated populations. Overall, the SSR markers used in this study were highly polymorphic and efficient in revealing the level of genetic diversity present in the studied germplasm.

Black cumin (Nigella sativa) is an important medicinal plant belonging to the Ranunculaceae which produces large diversity of secondary metabolites especially terpenes. Mono (C10) and tri-terpenes (C30) are two major structural classes of terpene compounds. Several genes are involved in biosynthetic pathway of the monoterpenes known as MEP pathway, located in plastids. In the MEP pathway, monoterpene synthases are rate- limiting enzymes for monoterpene biosynthesis. In the biosynthetic pathway of monoterpenes geranyl diphosphate synthase catalyzing geranyl diphosphate (GDP) biosynthesis as universal precursor of monoterpenes. Oxidosqualenecyclases is of the most important. In this study gene expression patterns of a monoterpene synthase, GDP synthase, beta amirin synthase and squalene oxidase were evaluated under salicylic acid treatment. Gene expression analysis of the genes at trasnscript level using semi-quantitative PCR in response to salicylic acid treatment revealed their differential expression.

Jatropha curcas is a tropical fast growing tree from euphorbiaceae family. The valuable species has medicinal, industrial and ornamental applications. Regeneration of the species was performed by seeds and cuttings. Regarding Jatropha's seed nature (oily seed), for which low germination is resulted, regeneration of the species was studied by stem cuttings. For micro propagation, apical buds of 2 and 4 years old genotypes̉ (Gen 1 and Gen 2) from different seasons were applied. The best treatment of sterilization was found to be HgCl2 0.1% solution for 10 minutes on fall samples for genotype 2. The best medium for shoot proliferation was MS medium with BA (3 mg/l) and IBA (0.1 mg/l). Effect of genotype on shooting was nonsense but genotype 2 had higher effect on growth factors. The most rooting of shoots was observed in modified MS medium supplemented with 1 mg/l of IBA. Plantlets were acclimated in greenhouse after transferring to soil.

Eucalyptus occidentalis is cultivated for its nectar and pollen in honey production, also due to its essential oils for medicinal aspects, tanin in leather industries and wood fibers in cosmetics and paper industries. Micropropagation of the species was evaluated by auxiliary bud culture in MS and GD culture medium using a factorial experimental model based on a completely randomized design. Seeds were immersed in water for 2 hours and 1% sodium hypoclorite solution for 18 minutes as the best treatment for surface sterilization. A modified MS medium containing cytokinines BAP, GA3 and IBA in 0.5, 0.15, 0.01 mgl-1, respectively and 200 mgl-1 PVP was used. The best rooting treatment was a modified MS medium (1/2N) containing auxine, IBA in 2mgl-1. Plantlets were transferred to soil and kept in greenhouse conditions. The study showed that using an appropriate treatment in tissue culturing method, the valuable species could be propagated in a short time.

Peroxidase enzyme has considered by researchers as an indicator of physiological changes in plants. The main purpose of this study was investigation of qualitative and quantitative changes of peroxidase isozymes of maple in Hezarjarib forest in Mazandaran province, Iran. At middle of autumn, 30 maple trees were selected in three altitude ranges (less than 700, between 800 to 1000, more than 1500 meters above sea level). Samples were taken from trees trunk bark. After enzyme extraction from the samples, quantitative studies were performed by spectrophotometer and qualitative studies were done using polyacrylamide gel electrophoresis. Based on peroxidase activity on the bark of the maple trees, significant differences were observed between the sites in low-, mid- and high-lands. Accordingly, the three altitudinal sites in terms of quantitative enzyme activities were largely segregated from each other. Qualitative assays of peroxidase activity showed that the enzyme was efficient for studying genetic variation within and between maple habitats. Furthermore, the results indicated that frequency of emergence of cathodic bands in high-land and mid-land forests were more than that in low-land. This is probably related to the spring frost that can be attributed to the higher altitude of 800 meters.

During early stages of breeding programs for large populations of forage plants, general combining ability (GCA) can be used to select superior families for development of a synthetic variety. Tall fescue is one of fescue species that are economically important and widely used as a forage grass. Tall fescue is self-incompatible and wind cross pollinated. This study was conducted to evaluate general combining ability of 25 polycross families of the species during 2012 and 2013 at a research station in Isfahan, in center part of Iran. Number of days to pollination, plant height, number of fertile tiller, length, and width of flag leaf, spike length, seed and forage yield of the families were evaluated. For number of days to pollination, genotype 13 and genotype 23 had the most and the least GCA (6.24 and -7.76), respectively. For fresh forage yield and dry forage yield, genotypes numbered 15, 18 and 19, 20, 23 and 24 had the most GCA. The six mentioned genotypes also had the most values for seed yield. It seems that crosses between the genotypes may produce synthetic varieties with high yield capacity. Cluster analysis grouped the families in four clusters. Analysis of variance showed that the third group had the highest mean for forage yield. Variation in GCA values was observed in most of the studied traits. Simultaneous studies of cluster analysis and GCA of the genotypes can help to find the best parental genotypes to produce synthetic varieties in future breeding programs.

Chicory (Cichorium intybus) is an old volunteer pharmaceutical plant. Root, leaf and seed of the plant contain Inulin, Sesquiterpenoid lactones, Coumarin and Flavonoids. Chicory cultivation is developing as the main source of Inulin at Europe countries, Japan, China and other countries. This investigation was done to evaluate 11 Iranian genotypes of chicory for Inulin production along with a Hungarian population of root chicory as a control during 2012. Genotypes were planted on mid March at Institute of Food Science and Technology, Mashhad, Iran. Traits under study were leaf width and length, root and shoot dry weight and their ratio at two stages (beginning of rosette and one month before harvesting date), time of flowering stem formation, bud number in crown, hair of leaves and stem, and final plant height. It was approved that there is no correlation between Inulin percentage and Inulin yield of chicory, therefore, root yield, the most effective component of Inulin yield, was identified as the major cause of increase of Inulin production. Dry root weight per plant was favorable at first sampling at rosette stage to before stem elongation and flowering (8 weeks after sowing) in Iranian genotypes and even Mollasani genotype had significant higher dry root weight than control. But this trait was significantly lower than that of control at the second sampling (26 weeks after sowing), one month before harvesting.

Acer is a tree from Aceracea family. Acer is one of the plants in danger of extinction. Problem with the species is rooting of cuttings and seed germination. The purpose of this study was to determine an optimum media for plant regeneration by tissue culture. MS medium supplemented with different concentration of oxin and cytokinin were used for buds regeneration. The best treatment for sterilization was %0.1 mercuric chloride for 3 min., %70 ethanol for 3 min. and NaOCl for 20 min. For regeneration of the cuttings, MS media supplemented with different plant growth regulators were used. The study was carried out based on a completely randomized design with 4 replications. Results showed that MS medium supplemented with 5 mg/l BAP + 0.1 mg/l IBA and 0/0002 mg/l TDZ was the best media for regeneration, Also the best treatment for multiplication was MS media with doubled Fe and 0.005 mg/L TDZ + 0.5 mg/L Kin. Rooting was observed on hormone free ½ MS media with 2 times Fe. Plantlets with acceptable growth and rooting were transferred to Jiffy pot and eventually transferred to soil.

In order to study drought tolerance indices and to identify drought tolerant accessions, 16 accessions of Elymus pertenuis were evaluated under dry land and irrigated farming systems using a randomized complete block design with three replications for each environment in a research farm of Hossein Abad, Shiraz, Iran. Five drought tolerance indices including stress susceptibility index, tolerance index, stress tolerance index (STI), mean productivity (MP) and geometric mean productivity (GMP) were estimated. Analysis of variance for each maturity group showed that there was a significant genetic variation among the accessions for all of the mentioned criteria. Correlation analysis showed significant positive correlation coefficient between STI, MP, GMP and yield under both dry land and irrigated conditions, suggesting that the indices are more efficient in determining drought tolerant accessions. Over all, Eghlid, Asadabad and Bardeh accessions, with average yield of 6323, 5560 and 5666 kg ha-1 respectively, were introduced as suitable accessions for dry farming cultivation in dry land and irrigated farming systems. Classification of the accessions was performed using cluster analysis based on the three indices of STI, MP and GMP.

In order to introduce drought tolerance indices on 48 accessions of Aegilops cylindrica an experimental augmented design based on a randomized complete block design with 4 replications was conducted under non-stress and drought stress conditions at Agricultural Research Station of Ilam University. Combined analysis showed variation among the genotypes and also showed different responses of genotypes in stress and non-stress conditions. Based on the results of simple correlation analysis between the indices and biological yields of populations, Arithmetic Mean Productivity, Geometric Mean Productivity, Harmonic Mean Productivity and Tolerance Index showed strong correlation with biological yield in both stress and non-stress conditions and were efficient in screening populations. Principal components analysis showed that the first and second components were able to explain 91.49% of the variation. The first component, explaining 61.26 % of variation, confirmed the efficiency of mentioned indices for screening tolerant populations. Accordingly, with respect to the distribution of populations in biplot made by the first and second components, populations 9, 24, 34, 43, 42, 35, 45, 47, 48, 23, 18, 3, 26 and 4 had the highest performance in both normal and drought stress conditions and based on Arithmetic Mean Productivity, Geometric Mean Productivity, Harmonic Mean Productivity and Tolerance indices had a good tolerance to drought stress. Populations 14, 36, 10, 32, 17, 20, 12, 15, 46, 40, 11 and 37 had good performance in normal conditions. Populations 25, 41, 33, 5, 6, 2, 7, 44, 1 and 8 had optimum performance in drought stress. Populations 13, 16, 19, 21, 22, 27, 28, 29, 30, 31, 38 and 39 had week performance in both normal and drought stress conditions. Cluster analysis was relatively confirmed by principle components analysis. Populations 34, 24, 43 and 9 were introduced as tolerant populations with high biological yield in both normal and drought stress conditions at Ilam province climates.

Proteins as direct products of genes are considered as the appropriate markers to assess genetic diversity and to identify resistant individuals. For investigation of Cypress (Cupressus sempervirens) seed storage protein based on quality activities by using SDS-PAGE method, 40 samples were taken on dried and healthy trees on two altitude classes. Results showed that weight of molecular bands on electrophoretic pattern of protein bands were between 18 and 125 KDa. Results of clustering and discriminant analysis also showed that trees from the two altitude classes could be distinguished by protein bands, but trees with different dried degrees could not be distinguished. Genetic diversity indices such as Shannon index and Nei, polymorphism percentage, showed trees with low and high dried degrees had the highest and lowest degree of the indices, respectively. Also trees from high altitudes had higher genetic diversity than trees from low altitudes. Diversity within the populations in the two altitude classes was more than variation between the populations. Also Genetic variation among altitudes in different populations (FST) was equal to 0.42. Therefore, results implied that Cypress trees in the studied region contain high genetic diversity, especially at high altitude. Also we could not distinguish dried and healthy trees by using seed storage protein.

In order to study morphological and physiological responses of Persian oak trees leaves, one of the dieback affected stands in Melah-Siah region in the northern half of the Ilam province was selected. Oak trees were divided into 4 groups with 6 replicates based on the severity of crown dieback. Leaf samples were randomly taken in South directions of trees crown in spring and summer during two consecutive years and were transferred to the laboratory for analyzing of some morphological and physiological traits including leaf area, wet and dry leaf weight, SLA, LMA and RWC. Results showed that the interaction effect of season and crown dieback degrees on morphological and physiological traits was not significant. But all of the studied traits had significantly ascending or descending temporal variations. Results showed that the dry leaf weight of dieback trees in spring 2014 was more than that of healthy trees. The leaf area of dieback trees in spring 2013 and in spring and summer 2014 was less than those of healthy trees. The amount of leaf water of dieback trees in spring and summer 2013 was less than that of healthy trees. The leaf moisture weight of dieback trees in spring and summer 2013 and spring 2014 was less than that of healthy trees. The RWC amount of dieback trees in spring and summer 2013 and spring 2014 was less than those of healthy trees. It was concluded that drought has more severe impact on the morphological and physiological status of Persian oak dieback trees leaves and responses of some traits in the dieback trees is for resistance to drought condition and possibly performance of vital activities.

In order to evaluate genetic variation and relationship among 16 genotypes of Stipa barbata, an experiment was conducted based on a randomized complete block design with 3 replications at Fozveh research station of Isfahan, during 2013-2014. Results of analysis of variance showed significant differences among the genotypes for all of the studied traits. Broad sense heritability was moderate to high (60-99%) for all of the traits except leaf length. Polkalle and Meymeh genotypes had the highest herbage yield and seed yield (3129, 2804 and 409, 265 kg/h, respectively). Correlation coefficients showed a positive correlation between seed yield and forage yield. Using principal components analysis, the first six components determined 83% of total variation. Plant dry weight, seed weight per plant, herbage yield, and seed yield were the most important traits in the first component. Stem height at maturity and cover in the second component, leaf length in the third component, panicle length at seed maturity stage in the fourth component, panicle length and plant height at anthesis stage in the fifth component and number of panicle seeds and panicle seeds weight in the sixth component were noticeable. Genotypes were classified into 3 groups with distinct variations for seed yield and forage yield.