مجله پژوهش های ژنتیک گیاهی
سال هفتم شماره 1 (بهار و تابستان 1399)

In order to determine the most effective indices for quantifying drought tolerance and identify genotypes that are tolerant to water stress in bread wheat, 50 bread wheat genotypes were compared in a randomized complete block design with three replications under both the non-stress dry farming with two complementary irrigation and the water stress dry farming conditions in Khorramabad, Iran. Analysis of variance showed that there was a significant difference among the genotypes in terms of all of the traits except the number of spike per area. In this study, eight indices including: Stress Tolerance Index (STI), Geometric Mean Productivity (GMP), Mean Productivity (MP), Yield Index (YI), Harmonic Mean (HM), Yield Stability Index (YSI), Stress Susceptibility Index (SSI), and Tolerance index (TOL) were calculated by using of seed yield of the genotypes under both conditions. Indices that selection based on them will improve the yield in both conditions, are considered as suitable index. STI, GMP, MP and HM were introduced as suitable index for drought resistance selection. Genotypes Shiroodi and S-90-5 were determined as the most appropriate based on 3D plot. Based on positive correlation between water stress resistance indices and yield under stress and non-stress environments, STI and GMP were the best indices. By using the Biplot method, Shiroodi, S-90-5 and Oroum genotypes were considered as high yielding potential genotypes under the both conditions. According to the results of cluster analysis, genotypes were classified into three groups based on drought tolerance indices. Graphical analysis of genotypes also showed that genotypes Shiroodi and S-90-5 were more profitable than others under both drought stress and non-drought stress conditions. These genotypes could also be used as parents caring desirable genes in the crossing programs and selection of tolerate genotypes.

In order to determine yield stability of 23 bread wheat genotypes and two commercial cultivars as check, an experiment was conducted based on a randomized complete block design with three replications in the experimental field of faculty of Agriculture, Razi University Kermanshah (Iran), during three cropping seasons (2015-2018). The results of combined ANOVA showed that the effect of environment, genotype and genotype × environment interactions on grain yield were significant (P<0.01). Stability was evaluated using environmental variance statistics, coefficient of variation, Wrick´s ecovalence, Shukla’s stability variance, Regression slope, deviation from regression slope, Plaisted and Peterson method and AMMI model. Variance analysis of additive main effects and multiplicative (AMMI) showed that three IPCAs were significant at 1% probability level. The first three principal components justified a round 85.7% of the sum of square of the interaction. Also, AMMI stability value (ASV) was used for simultaneously using information obtained from two significant components of AMMI. According to ASV index, genotypes Pishgam, Wc-4958 and Pishtaaz had the lowest ASV value and were known as the most stable genotypes. Genotypes Wc-4987, Wc-47615, Wc-47399 and Wc-47638 had the highest ASV value and distance from the center of Bi-plot. Therefore, Pishtaaz is one of the most stable genotypes due to having the first rank in terms of studied parameters as well as proper bakery properties and desirable drought resistance. In general, regarding to the climate change in the country, especially in the rainfed conditions and based on the above statistics and the biplots derived from AMMI analysis, the Wc-4958 line, with pishtaaz and Pishgam cultivars as stable and adaptable genotypes, are suggested to rainfed conditions on the studied area.

Estimation of genetic diversity and evaluation of plant germplasm is the most important step in collection and management of plant genetic resources. Also, comparison of different DNA-based genetic markers in diversity evaluation and then advising the most efficient markers is very important. In order to investigate genetic variation among Persian oak (Quercus brantii Lindi.) populations of Lorestan province (Iran), 20 genotypes were collected from different geographical and climatic regions. After DNA extraction, polymerase chain reactions (PCR) were used for study of polymorphism using three markers including ISJ, ISSR and SCoT. Genotyping was performed using the polymorphic bands obtained from all three markers separately, and also by combining the data of three markers. PCR results of the primers showed 91 polymorphic bands with an average of 71% per locus. The ISSR marker with 44 bands had the most polymorphic bands. Genotypes were discriminated by ISJ, ISSR and SCoT markers in 5, 6 and 5 groups, respectively, and using the combined data of three markers, genotypes were classified in 5 groups (each group included more than one genotype) and 3 group (each group included one genotype).  The results showed that the obtained clustering by different markers were nearly consistent with clustering of genotypes based on the climatic origin of genotypes. The most similarity between the groupings was between ISJ and ISSR markers with 89%. Overall, the results indicated the usefulness of markers used to estimate genetic distances between different oak communities.

Mutagenesis has been one of the important sources of genetic diversity and Plant mutants can be important bio-resources for crop breeding and functional genomics studies. Breeding conventional methods for generating of genetic variability are of low efficiency. We showed that treatment of seeds of rice(Hashemi cultivar) with 0.8% EMS for 8 h caused visible phenotypic variations on M2 rice mutant genotypes including flowering date, plant height, number of fertile tiller, panicle length, number of filled and unfilled grains per panicle, grain width and length, 100 grain weight and grain yield. The phenotypic variation coefficients of most traits found to be more than the genetic variation coefficients. The number of filled grains per panicle and seed length had the highest and lowest general heritability, respectivly. The seed yield had also high heritability. Analysis of correlation between different characteristics in the mutant genotypes showed that the number of fertile tillers and the number of unfilled grains per panicle had positive correlation with yield. Also, grain yield exhibited positive and significant correlation with panicle length, number of tillers and number of filled grains at genotypic level. In multiple regression analysis by stepwise method, number of tillers, number of filled grains per panicle, 100-grain weight, and grain width entered into the model, respectively, that explained 96 percent of grain yield variations. Results of grain yield and its components path coefficient analysis showed that the number of tiller had the highest direct effect (0.77) through than other traits on grain yield and, therefore it can be considered as major trait in grain yield improvement in rice. Also, based on results of this research and by using optimal selection index, mutant genotypes EM 18-17-5 and EM 15-14-1 were selected as superior mutant genotypes. This mutant population is expected to be serves as a genetical resource for understanding rice biology as well as for use in genetic improvement of quantitative traits.

Ferulago angulata (Schlecht) Boiss is one of the valuable and endemic medicinal plants of Iran, which is of great importance due to the source of terpenoid compounds and antimicrobial properties. In current study, the effects of different concentrations of salicylic acid and yeast extract in cell suspension culture of F.angulata on expression pattern of the HMGR and GPPS genes (involved in terpenes biosynthesis) were investigated for the first time. The F. angulata cell suspension cultures were initiated and established using calli derived from leaf explants, and salicylic acid and yeast extract elicitors (with 50, 100 and 150 mg/L concentrations) were added to the cultures during active growth. Then, the cell samples were prepared at 24, 48 and 72 hours after treatment. Analysis of expression pattern of HMGR and GPPS genes using Real-time PCR showed that the expression of both genes were significantly influenced by the type and concentration of the elicitors and also the times after treatment. The relative expression of HMGR and GPPS genes under elicitors were increased compared to the control, and furthermore, the increase in the relative expression of these genes under salicylic acid treatment was significantly higher than that of yeast extract treatment. The highest relative expression of GPPS and HMGR genes was related to 100 mg/L salicylic acid treatment at 24 hours after treatment. However, the highest relative expression of these genes was observed under the 24 and 72 hours after treatment of 150 mg/L yeast extract. The results of this study could be useful in metabolic engineering of F. angulata.

Anise is an annual plant belonging to Apiaceae family and fruit essential oil of this herb is used in various pharmaceutical, cosmetic and beverage industries. Drought stress is one of the most critical limiting factors for anise production in worldwide. In this research, to finding interrelationships among different traits and performance, some anise genotypes were evaluated using the biplot method. In this study, 18 anise genotypes were evaluated in normal irrigation regime and drought stress conditions according to a randomized complete block design with three replications at the field of the Western Australia University (UWA), Australia. Fifteen phonological, morphological and physiological traits were measured. Results indicated the positive and significant correlations between yield and fruit number and fruit thousand weight in both conditions. Due to the negative correlation between phonological features with fruit yield in two different irrigation conditions, it could be concluded that to have genotypes with high fruit yield, selection for early ripening genotypes should be done in anise. In this study, a significant correlation was observed between fruit yield and relative water content in the stress condition. Therefore, this trait can be used as a physiological index to evaluate drought tolerance in anise. According to cluster analysis based on the measured traits, genotypes were divided into 3 groups in both non-stress and stress conditions. According to the results of the comparison of the means of the groups in non-stress and drought stress conditions, genotypes No. 1, 5, 6, 11, 12, 14, 15 and 16 were identified as the most drought-tolerant genotypes. These genotypes could be utilized in breeding programs for further improvement of drought tolerance in anise germplasm.

In a breeding program, it is important to find out information about the genes action, because knowledge in this field could help the researchers in their crossing programs and realizing effective selection. In this study, breeding values of different agronomic traits in oriental tobacco were predicted using the best linear unbiased prediction (BLUP) procedure. For this purpose, 89 tobacco genotypes were evaluated in a randomized complete block design with three replications under normal (without broomrape) and stress (with broomrape) conditions at Urmia Tobacco Research Centre, during two successive years. Broomrape stress was applied by mixing 0.06 gr broomrape seed with soil in pots. C.H.T.209.12e × F.K.40-1 genotype had high yield under both normal and broomrape stress conditions and was one of the desirable genotypes in terms of yield tolerance and stability index. The Rustica genotype was the best genotype in terms of the breeding value of most of studied traits in both normal and broomrape stress conditions. The result from cluster analysis based on the breeding values of the studied traits showed that, tobacco genotypes were divided into 6 and 5 groups in normal and broomrape stress conditions, respectively; but the distribution of genotypes within the groups was different depending on the conditions. The highest heritability was observed for root fresh weight under normal condition and for leaf fresh weight under broomrape stress conditionss. The results showed that a genotype with good phenotypic performance may have low breeding value. Therefore, considering breeding value information along with phenotypic mean of traits can increase the efficiency of breeding programs.

Saffron (Crocus sativus L.) is the most valuable and expensive spice in the world. The stigmas of saffron are the source of valuable apocarotenoids such as crocin, picrocrocin and safranal. transcriptomic and expression studies of genes are important steps in investigating of secondary metabolites in plants. One of the important prerequisites for such studies is the existence of reliable and stable reference genes to normalize the expression of other genes. In the present study, eight reference genes were identified and isolated using transcriptome of saffron and their expression stability was evaluated by nonparametric statistics and methods. The results of amplification and sequencing showed accurate identification of eight reference genes Actin, EF1, GAPDH, H3, MDH, TBP, UBC and UBQ. The expression stability evaluation revealed that MDH and UBQ genes had the highest stability among different saffron tissues and TBP had the lowest stability among them. In this study, for first time, eight reference genes were isolated from saffron and their expression stability was evaluated. The reference genes identified in the present study can be used as stable genes to normalize gene expression in transcriptomic and expression studies of saffron plant.

Astragalus with more than 800 species is one of the largest plant species in Iran and most of its species are medicinal and native. In this study, karyotypic characteristics of 21 populations from 13 species including A. vegetus, A. iranicus, A. vanillae, A. chrysostachys, A. glycyphyllos, A. bombycinos, A. campylorrhynchus, A. macrourus, A. caragana, A. ebenoides, A. pseudocyclophyllus, A. stevenianus and A. jodostachys were examined and compared. The results showed that there was a significant difference between the populations in terms of all measured traits (TL, LA, SA, AR, CI, TF%, DRL, LA% and SA%), except for traits A1 and A2. Population 25786 of A. vegetus species from Khorasan with average length of 4.51 μm had the highest total chromosome length and population 13764 of A. vanillae species from Qom with 2.67 μm had the lowest mean total chromosome length. According to the values of AR, CI, TF%, A1, A2, DRL, LA% and SA%, population 3421 of A. vegetus species is the most asymmetric and population 29586 of species A. campylorrhynchus had the most symmetrical karyotype.

water stress and, in this regard, it is necessary to improve rice cultivars to tolerance to environmental stresses. In this research 154 recombinant inbred lines (F9) derived from a cross between Shah-Pasand and IR28 in three conditions (non-stress, osmotic stress -0.3 and -0.6 Mpa induced through polyethylene glycol-6000) were evaluated as a factorial experiment in randomized complete block design. In addition, for molecular polymorphism experiment, 110 SSR and EST-SSR markers were assessed on parents of population and among them, 41 markers identified which had proper polymorphism between two parents. The regression analysis between germination components and molecular markers revealed the most coefficient of determination were found in RM211 for allometric coefficient (17%) under non-stress, RMES10-1 for Plumule dry weight (18%) under -0.3 MPa; and RM273 for germination uniformity (22.7%) under -0.6 MPa. RM3496, RM452, and RMES6-1 in three conditions had the most number of significant relationships with six, three and eight traits, respectively, and they can be a suitable candidate for simultaneous improvement of several traits in breeding programs of marker-assisted selection. In addition, after the identification of significant markers associated with germination components, the closest genes to these markers were identified using bioinformatic analysis, and the analysis of their expression were performed by rice transcriptome database. According to the results, the maximum gene expression pattern under drought stress and under non-stress conditions were related to loci LOC_Os01g57220 and LOC_Os01g26039, respectively and this information could be applied in breeding programs.

Drought, an abiotic stress, considered as one of the factors limiting food resources. The plant responses to adaptive to such a condition are accompanied with changes in the expression pattern of some functional as well as regulatory genes. The MYB proteins include a big family of transcription factors which are highly important in regulating development process and immunizing responses of plants. This research was conducted to evaluate the expression of TaMYB73 transcription factor and catalase and polyphenol peroxidase enzymes activity in bread wheat cultivars (Hamoon, Hirmand, Kavir, Bolani, and Cross Bolani) under drought stress conditions. Factorial experiment was conducted in pot based on a completely randomized block design with three replications. Following 45 days from seed planting (four- leaf stage), drought stress was done at five levels of different irrigation and then the leaves of treated plants were sampled to measure of enzyme activity and gene expression. After RNA extraction and c DNA synthesis, the gene expression pattern was evaluated using Real-time PCR and data analysis was performed via 2-ΔΔ ct method. The results showed that TaMYB73 gene expression level as well as the catalase and polyphenol peroxidase enzymes activities corresponding to the Hirmand cultivar was higher than the other cultivars.