فصلنامه ژنتیک نوین
سال نهم شماره 1 (پیاپی 36، بهار 1393)

Genetic variation between 45 genotypes of different types of tobacco germplasm, including aircured (burley), flue-cured (virginia) and sun-cured (oriental) tobacco was assessed using 12 ISSR primers. Out of 170 bands, 128 showed polymorphism and number of polymorphic bands ranged from 6 to 14 per primer. Polymorphic Information Content (PIC value) in total genptypes studied ranged from 0.16 to 0.33 and Marker Index (MI) ranged from 1.21 to 3.55 per primer. Principal Coordinates Analysis showed that the aforementioned values could explain total variation of 69.61 percent. In this study, cluster analysis using WPGMA, placed 45 genotypes in six cluster groups. The group I and III included burley type, group II flue-cured and groups IV, V and VI oriental tobacco genotypes. Discriminate Function via Fisher's linear (73.3 percent) confirmed the validity of clustering analysis result.

The genetic changes of periodic records of egg production were investigated using Random Regression models. The used data were measured on 2310 birds descended from 46 sires and 618 dams. Of these 2257; 2205; 2102 and 1965 records of egg numbers were collected at 20-32 (1st period), 32-44 (2nd period), 44-56 (3rd period) and 56-68 (4th period) weekly, respectively. In the model analysis all important fixed (such as age and hatch) and random effects (such as direct additive genetic effects and animal permanent environmental effects) were included. Genetic analysis were started with k=2 for both direct additive genetic effects and animal permanent environmental effects; and completed with higher order of fitting up to k=4. Fitting a model with k=3 for the additive genetic effects and k=2 for animal permanent environmental effects was found as the most parsimonious model. Accordingly, the heritability of egg number for period 1, period 2, period 3 and period 4 were estimated to be 0.43, 0.12, 0.16 and 0.11, respectively. The proportion of permanent environmental variance to phenotypic variance was increased from 0.38 for 1st period to 0.6 for 4th period. In this study, the genetic correlations across the ages of egg production were estimated. The value of the genetic correlations shows that the ages of egg production represent 4 different traits. Therefore the selection accuracy could be increased when additional records. However, the benefit of using the additional measurements in the breeding program should be investigated.

Sclerotinia stem white rot is one of the most important diseases of canola in many regions under cultivation of this valuable crop plant. The extent of infected plants in some fields reaches to 80% and sometimes the severe infection damages 50% of the crop yield. The disease caused by Sclerotinia sclerotiorum, is casual agent of stem white rot and ring in canola, sunflower and other plants such as cabbage, lettuce, tobacco etc. The casual fungus is one of the main plant polyphagous pathogens that has a wide host rang. In this study 33 samples of canola, sunflower and cabbage were collected from different areas of Golestan province in 2008-2009 and cultured on PDA medium. Nineteen mycelial compatibility groups (MCG) were obtained for studying compatibility reaction between cultured isolates (couple or single). From 171 crosses between isolates, 21 (12.3%) showed mycellial compatibility and 150 (87.7%) showed incompatibility. Furthermore, in order to study molecular diversity of obtained isolates, 8 RAPD primers were used in PCR. Totally, 136 ploymorphic markers were obtained in agarose gel electerophoresis. Analysis of molecular data using PopGene32 software indicated that there was a high genetic diversity among studied isolates. Furthermore, results showed that similarities were not associated to spatial distribution of collected isolates. On the basis of Hardy–Wineberg test it can be concluded that studied population is in equilibrium at all studied loci. This status may be due to being young the canola culture in Golestan province, existence of many hosts (particularly among weeds) and low variation of canola varieties cultivated in recent years in the region. Results indicate the efficiency of RAPD marker for studying genetic variation in Sclerotinia sclerotiorum fungus.

Stability and gene expression are very important in the plant transformation. In this research the transgenic alfalfa plants containing cry3Agen (resistant insect pests) from Bacillus turingiensis var. tenebrionis were analyzed. In This study, transgenic alfalfa that were grown in the regeneration medium MS without hormones, were transferred to pots, and the presence of transgen was confirmed by PCR and Sothern blot hybridization. Expression of the Cry3A protein in transgenic plants was also confirmed by using DAS ELISA kit. The bioassey analysis of transgenic plants for alfalfa weevil larvae showed that percentage of mortality of larvae in control plants were 13-30%, while in transgenic plants it was observed between 33-90%, that was statistically significant (α<0.01). Average of percentage of leaf damage in control plants were 67-85% while amount of leaf damage in transgenic plants significantly reduced to 18-21%. Average live weight of larvae in the control plants was 0.02 mg but in transgenic was 0.001 mg.

To investigate the genetic variation and population structure of Siahmahi (Capoeta capoeta gracilis), one of the native species of Iran which molecular information about it is scare, 30 samples were collected from each Madarsu river in Golestan National Park, and Gorganrud river. Genomic DNA was extracted from fin tissue by phenol-chlorophorm method. PCR was performed using microsatellite primers. Results showed that all of the 9 microsatellite primers that used in this study were polymorphic. The average number of observed and effective allele were 10.2 and 7.45 respectively, and the average of observed heterozygosity was 0.98. Both the studied populations deviated from Hardy-Weinberg equilibrium proportions at a number of loci, mostly due to the exsses of heterozygosities. The Nei genetic distance between populations was 0.139 which indicated that genetic differance among the studied population was pronounced. The data generated in this study provide useful information on the genetic variation in populations of Siahmahi for management and conservation programs of this valuable native species.

To evaluate the cytogenetic diversity of six selected exotic and domestic Persian walnut cultivars\genotypes, relationships among the cultivars, Z63, Pedro, Z30, Serr, and the genotypes, B21 and K72 were studied using Karyotyping of cells obtained from their roots. The karyotyping was done using 10 samples at metaphase stage. The parameters measured were chromosome long arm, short arm, short/long arm and short/whole chromosome length ratios, and chromosome index. All samples were diploid with 32 chromosomes, 2n=32. The types of chromosomes identified were all with no satellites, mostly of metacentric and submetacentric kinds and rarely telocentric type was observed. The average size of chromosomes in the genotypes studied was 8 microns. In order to classify the cultivars/genotypes studied based on their karyotypes’ characteristics, cluster analysis using Ward method was applied and the cultivars/genotype were categorized into three distinct groups: Group I, (K72, Z30, Z63, Pedro); Group II, B21 and Group III, where Serr was classified into it alone.

The purpose of this study was to identify QTL affecting lymphocytes, body temperature and tonic immobility on Japanese quail chromosome 3. 422 birds from F2 generation were measured for leukocytes, body temperature and tonic immobility and all of the 472 birds (related to three generations) were genotyped for 3 microsatellite markers on chromosome 3. QTL analysis was conducted using the interval mapping method. No QTL was detected for body temperature and tonic immobility. Although the main QTL effects were not significant for the studied traits chromosome wide significant QTL were found for percentage of heterophil, percentage of lymphocytes, ratio of heterophils to lymphocytes (at 38 cM) and percentage of eosonophils (at 7 cM) (P<0.05) in analysis of interaction of hatch and QTL. Chromosome wide significant QTL were also found for percentage of monocytes (at 34 cM) (P<0.01) and percentage of eosinophils (at 5cM) (P<0.05) in the analysis of interaction of sex and additive QTL effects.

Different species of Cucurbitaceae family are one of the most important sources of human food widespread in the world. One of the economically most important species of this family is melons (Cusumis melo L.) which are cross-pollinated and morphologically diverse plants. In the current investigation, genetic diversity of 11 Iranian landraces and 12 hybrid varieties of C. melo L. was assessed using 20 ISSR primers. The Twenty used ISSR primers generated 311 distinguishable and scorable loci, of which 52.26% were polymorphic. The highest values of heterozygosity (He) 0.135) and number of effective alleles (Ne) (1.23) observed for primer UBC820 while the lowest amount of those (0.031 and 1.058) was observed for primer UBC857. The average He for all studied genotypes was 0.155. The He value of hybrids was more than that for landraces. The highest value of He (0.177) obtained for landrace Zivari-shahrood (Zi-Sha), while landrace Tal-Shahrood (Ta-Sha) showed the lowest amount of He (0.118). Cluster analysis based on simple matching similarity coefficient using UPGMA algorithm grouped the genotypes in 7 groups. Population structure analysis using Bayes model confirmed the K 7, as the reliable value for the number of clusters. The hieghest value of Nei’s genetic distance observed between landrace Darghazi-tashkand (Dar-ta) and Durango hybrid. The landraces Darghazi-tashkand (Dar-ta) and Khatouni- Fariman (Kha-Far) had the lowest genetic distance. In conclusion, the current investigation demonstrated that ISSR markers might be useful in genetic diversity assessment of melons and obtained heterotic groups could be used in melons breeding programs.

Cold temperature is one of the important abiotic stresses limiting the growth and development in plants. Usually, plants use a complex system to cope with such stress situation. Identification of acclimation mechanisms could be an important aspect in production of cold resistant plants. In this research, the phenotype and physiological characteristics as well as gene expression levels of two key stress responsive genes FRY1 and GST1 has been evaluated in response to cold stress-induced condition in the green mutant plants following comparison with the wild type plants Ler. Consequently, 17-day-old plants have been placed in 4 ºC for a long time following assessment of various phonotypical and phonotypical characterizations including total fresh weight, root fresh weight, duration of growth and development in diverse time points. The proper statistical approaches have been employed to analyze the obtained related data by using the SAS9 software. On the basis of the obtained results, the mutant plants showed more sensitivity and a prolonged growth and development in response to cold stress conditions when compared with the wild type plants. The expression levels both FIERY1, as one of the responsive gene to abiotic stresses in Arabidopsis, and GST1, as gene marker in oxidative stress, have been measured by Q Real Time PCR. Accordingly, 17-day-old plants have been placed in 4 ºC following leave sample collection in diverse time points, RNA extraction and cDNA construction. Gene expression levels of FRY1 and GST1 considerably decreased in mutant plants. As a conclusion, more sensitivity to cold stress condition might be a result of low activity of antioxidant systems in mutant plants.

DREB transcription factors are one of the four independent regulation systems in plants which involves in abiotic stress signaling pathway and activation of stress responsive genes. For identification and isolation of DREB genes, one-year-old own-rooted grapevine’ were used. Potted plants were subjected to150mM NaCl during the experiment and total RNA was extracted. Specific primers were designed based on predicted DREB and SbDREB2A gene homologue in halophilic plant Salicornia brachiata. VvDREB and VvsDREB (DREB like 2C) genes were isolated from grapevine (Vitis vinifera L.’ Askari’). Bioinformatics results indicated that VvDREB gene has 85% similarity with DREB2 genes from soybean family and VvsDREB gene has 80% similarity with SbDRE 2A gene. SbDREB2A and VvsDREB proteins motif studies in ELM database showed that there are no five motifs (BRCT, MAPK, PKB, NES, NLS) in VvsDREB protein.

Aset of 40 F2 bread wheat from two crosses between parents with desirable bread making quality (Tajan) and two mutant lines from Tabasi with high yield and undesirable bread-making quality (T- 66-58-9 and T-66-58-12) screened and used to investigate SSR and ISSR markers related to desirable bread-making quality. Therefore, the aim of this study was accomplishment to microsatellite and designed inter simple sequence repeat markers linked to Glu-1D genomic locus for identification of bread wheat mutant lines. The two parents were analyzed with 2 SSR primers pairs and 6 ISSR primers. Of these, 2 primers (25%) were showed high polymorphism between two parental genotypes each cross. Using these primers, electrophoresis results of F2 progeny were analyzed and mean of similarity coefficient were computed for each progeny. Primers, S2 and S13 showed very high polymorphism percentage and power of discrimination. These markers may be useful in genotyping and genetic diversity studies for the genetic improvement program of bread wheat cultivars and mutant lines.

Biodiversity is very important in species survival and plant breeding. The relationships of 10 Flax cultivars were investigated using 13 Random Amplified polymorphism DNA (RAPD) primers and 13 morphological traits. Thirteen arbitrary RAPD primers amplified 169 reproducible and scorable loci, which 87 bands were polymorphic (51%). The average number of polymorphic bands was 6.6 per primer. Genetic similarity among cultivars ranged from 0.67 to 0.86 with an average polymorphism information content of 0.16. The polymorphic information content reached the highest value of 0.29 at loci OPD-03 and OPA-06 (0.28). The dendrogram was depicted using NTSYSpc 2.02 software and six main clusters obtained. In morphological part, 13 different traits were measured and compared. Both markers showed high level of diversity among studied cultivars. According to the results obtained from cluster analysis, 97-2, 97-5, 97-24 and 97-25 varieties showed greatest genetic distance from other varieties, which can be used in breeding programs of Flax. Furthermore, 97-25, 97-24 and 97-5 varieties, had highest amount of seed yield. The results also propose that RAPD marker is a useful tool for evaluation of genetic diversity and relationships among different Flax varieties.

Using molecular technology has resulted in discovering the mutations with major effect on reproduction efficiency in goat. Because of the importance of litter size in goats, in this research, the mutations found in previous research and new mutations were investigated in Beetal and Tali breeds for BMP15 gene. After DNA extraction from blood samples of Beetal and Tali goats and PCR reactions, nine PCR products (from individuals with different kidding records) from mention breeds were sequenced. In Beetal goats no nucleotide change has been found for BMP15 gene. Also, a heterozygote mutation was found at position 807 in Tali that led to replacing a glutamine amino acid with a glutamic acid amino acid (Residue of 269). Due to the replacement of an uncharged amino acid with a charged amino acid, it is theorized that this mutation disrupts dimerization and leads to change in the electrostatic surface potentials of this loci and hence abolish biological activity.

The purpose of this study was to determine the presence or absence of a specific satellite DNA on the genus Acipenser (HindIII SatDNA) in Persian sturgeon, Acipenser persicus. Genomic DNA was extracted from caudal fin tissue of A. persicus specimen using the phenol-chloroform method to extract HindIII SatDNA. HindIII SatDNA amplified using the PCR technique and PCR product was evaluated by agarose gel electrophoresis after staining the gel with ethidium bromide. Obtained HindIII SatDNA fragment after extraction from agarose gel and purification, ligated to the plasmid PTZ/57R (Fermentas) and cloned in competent E. coli DH5α cells (Fermentas). Finally three clones containing the HindIII SatDNA fragment were sequenced. Sequencing of extracted HindIII SatDNA from genome of Acipenser persicus showed that it contained 163bp which is registered in NCBI as F 429174. Comparison HindIII SatDNA extracted from A. persicus in the present study with those extracted from Acipenser gueldenstaedtii, A. ruthenus, A. naccarii, A. brevirostrum, A. baeri, A. fulvescens, A. stellatus and A. sinensis showed 88% and with that from A. transmontanus showed 90% similarity. Presence HindIII SatDNA in A. persicus and high similarity between it and those from the mentioned sturgeons verify this fish belongs to Acipenser genus.