ahmad arzani

The severe impact of drought and salinity on plant productivity presents a significant threat to worldwide food security. Plants exhibit the capacity to sense stimuli in their environment and adjust defense mechanisms through diverse regulatory networks to cope with abiotic stress. The complexities of drought and salinity tolerances can be deconstructed into contributing factors and mechanisms, classified under two categories: genetics and epigenetics. Epigenetic mechanisms play a role in partially attributing crop adaptation to the most formidable drought and salinity stresses. Plants respond to stress in part by undergoing stable alterations in gene expression, a process that involves the physical "marking" of DNA or its associated proteins, commonly called epigenetics. Plants utilize various epigenetic mechanisms to refine gene expression, vital for adaptation and phenotypic plasticity. These include DNA methylation, histone modifications, chromatin remodeling, epitranscriptomics, and gene silencing mediated by small RNAs. Notably, epigenetic modifications can be inherited or erased. Enhanced knowledge of epigenetics complements genetics and will aid in developing strategies to integrate them into crop improvement programs aimed at addressing adaptation to abiotic stress. This review highlights the latest and noteworthy findings regarding crop epigenetic responses to abiotic stress signals, particularly those pertinent to drought and salinity tolerance.

Drought stress is the most prevalent and limiting factor in the growth and productivity of crop plants. According to the challenge of deficiency in precipitation or consecutive droughts in recent years in Iran and as a result of a shortage of irrigation water in wheat production, knowledge of the relationship between grain quality and grain yield under drought stress can be particularly important to identify lines with drought tolerance. The present study, hence, evaluated the effects of drought stress on the grain quality of 104 F5 lines derived from a cross between Barat × Nogal in wheat.

The effects of drought stress on grain-quality-related traits of wheat were investigated using 104 F5 lines under normal and drought conditions. A randomized complete block design with three replications was used in each environment in the 2020-2021 cropping season. Grain yield, protein yield, grain hardness, Zeleny sedimentation volume, protein content, bread volume, gluten content, and gluten index were evaluated.

Analysis of variance showed that there was significant genetic variation in the lines for all traits in both environmental conditions. Stress and stress × line interactions were also significant for all of the studied traits. Mean comparison of lines showed that the quality in bread wheat was improved under drought stress conditions due to increment in protein content and grain hardness. The highest grain protein content was found in lines 10, 52, 54, 68, and 71 with 12.96% under normal conditions, while it was found in lines 10, 28, 32, 61, and 93 with 13.94% under drought-stress conditions. Although the growth and consequently grain yield were limited under drought stress conditions, increased concentrations of grain‐derived ingredients including protein content, gluten content, gluten index, and Zeleny volume were noted. On the other hand, grain protein showed a significant and positive correlation with the Zeleny volume and water absorption in both environmental conditions.

From the work carried out it can be concluded that firstly, selection of wheat lines in respect to grain quality must be undertaken separately for each of the normal and stressed environments, and secondly that the grain quality of wheat lines under drought stress conditions was significantly better than that of normal field conditions.

Glycinebetaine (GB) accumulation in many halophytic plants, animals, and microorganisms confers abiotic stress tolerance to salinity, drought, and extreme temperatures. Although there are a few genetic and biochemical pathways to synthesize GB, but isolation of a single gene choline oxidase (codA) from Arthrobacter spp. have opened a new hatch to engineer the susceptible plants.  The effects of overexpressed codA gene, through multiple copy insertion and GB accumulation on salinity tolerance in rice were studied.  Seed-derived embryogenic calli of ‘Tarom Molaie’ cultivar were targeted with two plasmids pChlCOD and pCytCOD both harboring the codA gene using the biolistic mediated transformation. The regenerated T0plants were screened by PCR analysis. A line containing three copies of codA gene and harboring pChlCOD and pCytCOD was identified by Southern blot analysis. The expression of codA gene in this transgenic line was then confirmed by RTPCR. The Mendelian segregation pattern of the inserted sequences was accomplished by the progeny test using PCR. The effects of overexpression of codA on salinity tolerance were evaluated at germination and seedling stage using T2-pChl transgenic line and control seeds in the presence of 0, 100, 200, and 300 mM NaCl. Finally, leaf growth dynamics of T2-pChlCOD transgenic line and control line under hydroponic conditions in the presence of 0, 40, 80, and 120 mM NaCl were assessed. The seed germination experiment results showed that the transformed seeds had a higher germination rate than the controls under all salinity treatments. But also, the leaf growth dynamics showed that the control plants had a more favorable leaf growth dynamic in all of the treatments. Although, the transgenic lines (T0, T1 and T2) exhibited lower performance than the wild type, the transgenic line varied for GB and choline contents and increasing codA gene copy number led to increased GB content.  In a salinity sensitive crop such as rice, GB may not significantly contribute to the plant protection against salt stress. Also, insufficiency of choline resources as GB precursor might have affected the overall growth ability of the transgenic line and resulted in decreased leaf growth dynamics.

Plant genetic variation, during the long-term domestication of the cultivated barley, especially after the modern breeding and intensive cultivation, reduced significantly, leading to genetic erosion in this crop as well. Wild relatives of cultivated barley are potential source of valuable genetic materials for barley improvement. Genetic variation of wild species belonging to primary gene pool of barley is important in employing in barley breeding program, particularly for tolerance to biotic and abiotic stresses. Being a close relative of wild species (H. spontaneum L.) and the lack of tolerance genes among the cultivated genotypes of barley makes gene introgression the appropriate avenue to transfer desired genes such as abiotic stress tolerance.

In this research a backcross populations (BC2F1) developed from interspecific hybridization between cultivated barley and its wild relative (H. spontaneum L.) was assessed for genetic diversity using molecular markers which are valuable to assist background selection for recurrent parent.

Arliquin and POPGENE softwares were used to analyze genetic diversity and molecular variance (AMOVA) among populations, respectively. Gst and Nm parameters had an average of 0.59 and 0.34, respectively, indicating a low gene flow among nine groups of backcross families. The AMOVA results showed that majority of genetic diversity belonged to within population variation (86.48%). Nei's genetic similarity ranged from 0.41 to 0.92 which were consistent with those of genetic distance

Microsatellite markers have strong differentiation ability to discriminate the resultant genotypes from a bi-parental cross.

Given the increasing demand for food supply due to human population growth and the limited arable land, the role of plant breeding in increasing crop production is evident. Wheat (Triticum spp.) is known as an important food source in the world because of its adaptation to different environments. Triticale (X. Triticosecale Witmack) has high adaptability to biotic and abiotic stresses and is able to produce efficiently even in poorly fertilized soils and low input farming systems. Heterosis is a natural phenomenon that depends on the species and genetic variation and is called the increase in hybrid vigor of parents, which can be explored to increase crop production. Since the exploitation of heterosis is promising in wheat, the employment of putative hybrids for sustainable food supply has potentially increased. Hence, the aim of this study was to estimate heterosis and to evaluate the coefficients of phenotypic and genetic variation as well as heritability estimates.

A total of 79 genotypes including 19 common wheat, 3 durum wheat, 4 triticale along with their 53 F1 hybrids were used, in this study. Morphological traits including yield and yield components viz. plant height, number of spike per plant, number of grains per spike, grain weight per spike, 1000 grain weight and grain yield per plant were measured. The heterosis estimates in the studied hybrids were calculated based on the mid-parent and better-parent. After analysis of variance, coefficients of phenotypic variation, coefficients of genetic variation and general heritability were estimated.

The results of analysis of variance showed significant differences among the genotypes for the studied traits. Mean squares of parents versus hybrids were significant for all traits, indicating heterosis in the studied traits. F1 hybrid derived from Long Spike 2 × Sirvan cross had the lowest heterosis compared to the mid-parent and superior parent for plant height. The highest percentage of heterosis for grain yield per plant belonged to the hybrid derived from the cross between Long spike 5 × Roshan. The estimated heterosis for grain yield based on mid-parent value showed a range of 25.34 to –25.41, indicating the high genetic diversity of the parents used to produce the 53 F1 hybrids studied.

Given the genetic diversity observed in this study indicating heterosis in the studied traits as well as high heritability in the traits, the diversity can be explored either by hybrid breeding strategy or advancing segregating generations toward developing new cultivars.

Genetic diversity in field crops and their wild ancestors plays important role in breeding programs. The aim of this study was to investigate the genetic diversity of einkorn (Triticum monococcum L. ssp. boeoticum) wheat genotypes collected from western parts of Iran using SSR markers. 

In this study, genetic variation of 163 genotypes from 34 populations of einkorn wheat collected from western parts of Iran was investigated using 19 SSR loci developed in the A genome of hexaploid wheat.

In the investigation of 163 einkorn genotypes using 19 microsatellite loci were generated 151 polymorphic alleles with an average of 7.94 per locus. The content of polymorphic information content (PIC) in the studied einkorn genotypes ranged from 0.64 for Xgwm480-3A locus to 0.89 for Xgwm4-4A locus. The mean content of polymorphic information in the studied genotypes was 0.77. According to the results, Xgwm4-4A, Xgwm610-4A and Xgwm282-7A loci were identified as the most suitable primers for studying genetic diversity and differentiation of einkorn wheat genotypes. The mean of Shannon coefficient of 0.16 indicated moderate variation in genotypes under study. The average percentage of polymorphic gene loci in the 34 studied populations was 36.74 and the average heterozygosity was 0.114. Based on analysis of molecular variance for 34 populations, the variations between and within populations were calculated as 7% and 93%, respectively. Cluster analysis based on Jaccard coefficients and UPGMA algorithm classified the einkorn genotypes into 10 distinct groups. The results of the principal coordinate analysis revealed that the two primary vectors explained 29.33% and 24.01% of the total molecular genetic variance, respectively.

The results indicated the usefulness of microsatellite markers in identifying and grouping einkorn wheat genotypes, so that the obtained information could be used in breeding projects, germplasm conservation planning and collection of einkorn wheat populations.

Solvent retention capacity (SRC) as a valuable tool for measuring functional properties of each polymeric component of flour was introduced and developed by Louise Slade in the late 1980s. The SRC values were significantly correlate with flour chemical components, farinograph parameters and breadmaking parameters. The purpose of this research was to evaluate the relationships between SRC profiles and flour secondary structures and amino acids content of 12 cultivars of hexaploid triticale and comparing them with bread wheat, durum wheat and rye as close cultivars. In this study, four main solvents (deionized water, 5% lactic acid solution, 5% sodium carbonate solution and 50% sucrose solution) and four supplemental solvents (55% ethanol solution, 0.75% sodium dodecyl sulfate solution, 0.006.0% sodium metabisulfite solution , as well as combination of SDS and MBS solutions of the SRC test were used. According to the results, triticale cultivars with superior grain quality produced flours with much superior physical and chemical properties than other triticale cultivars. Flour dough of those cultivars had better rheological properties than other cultivars, and had much better alveograph quality parameters. Such flours had more disulfide bonds (SS) and lower sulfhydryl groups (SH) than other cultivars. Such flours were rich in gluten producing amino acid content. Also such flours had a higher Intermolecular-β-sheets and β-turn, and had less α-helix content. Such flours had more capacity for retention the main and supplemental solvents of SRC and showed high correlation with molecular parameters of flour. Therefore, the SRC test singly in determine and identifies cultivars with superior bread quality and thus to obtain the product with the best quality can be used, and is also justifiable at the molecular level.

Solvent retention capacity (SRC) is the weight of solvent held by flour after centrifugation that expressed as percent of flour weight, on a 14% moisture basis. The combined pattern of the four SRC values establishes a practical flour quality and functionality profile. The SRC test is a relatively simple, economical and user-friendly method. SRC technology is based on energetics, not kinetics. Dough rheological tests, in contrast, are based on kinetics of dough development, use limited amounts of solvent, and give information on rates of network development. The purpose of this study was to evaluate the application of the SRC test in determining flour dough alveograph parameters of 12 cultivars of hexaploid triticale and comparing them with bread wheat, durum wheat and rye as close cultivars, as well as determining correlation coefficients were between grain and flour and flour dough characteristics of triticale. In this study, four supplemental diagnostic solvents of the SRC test, which have a better understanding of the quality of gluten polymers, including 55% ethanol solution (ETHSRC correlated with gliadin properties), 0.75% sodium dodecyl sulfate solution (SDS) (SDSSRC, correlated with glutenin macro polymers properties), 0.006% sodium metabisulfite solution (MBS) (correlated with gluten properties), as well as combination of SDS and MBS solutions (correlated with glutenin macro polymers and disulfide networks properties) were used. The results showed, triticale cultivars with superior physical grain quality produced flours with much superior physical, chemical and molecular properties than those triticale cultivars with poor grain quality. In the following, such flours, which due to their high quality polymers, could have higher SRC values for SRC solvents, ultimately produced a dough that was superior in terms of alveograph parameters than those triticale cultivars and as a result had better bakery quality.

Solvent retention capacity (SRC) provides a measure of solvent compatibility for the three functional polymeric components of gluten proteins, damaged starch, and pentosans (arabinoxylans) which in turn enables prediction of the functional contribution of each of these flour components. The ability to analyze the individual functional contribution of each functional component of flour would enable end-users to better predict overall flour functionality and obtain optimized product quality. The purpose of this study was to evaluate the application of the SRC test in determining some of the most important characteristics of grain and flour of 12 cultivars of hexaploid triticale and comparing them with bread wheat, durum wheat and rye as close cultivars, as well as determining correlation coefficients were between grain and flour characteristics of triticale. In this study, four major solvents of the SRC test including deionized water (correlated with all flour polymer compounds), 5% lactic acid solution (correlated with glutenin polymers properties), 5% sodium carbonate solution (correlated with damaged starch content) and sucrose solution 50% (correlated with the arabinoxylans content) were used. According to the results, of triticale cultivars with superior grain physical characteristics, flours with much superior physical and chemical characteristics than those triticale cultivars were produced. During the SRC test, such flours due to the high quality of their polymer components, had more capacity for retention of the main solvents of the SRC test and had more favorable and high SRC profiles. Therefore, according to the results of this study, the solvent retention capacity (SRC) test, in terms of its significant and highly correlated profiles with parameters of other methods determining the quality of grain and flour, alone and easily in identifies superior quality cultivars and thus gaining the product with the best quality can be used.

Chrysanthemum morifolium is an important ornamental and medicinal herb in the world. Available reports revealed the presence of different organic and antioxidant compounds in different chrysanthemum cultivars. Also many biological characteristics such as antioxidant, anti-inflammatory, anti-bacterial and anti-virus are known for this plant. In this study, thirteen cultivars of C. morifolium were compared in terms of leaves total phenolic, flavonoid and antioxidant activity and also for their flower essential oil content.
Material and This research was carried out in a randomized complete block design with three replications at the research farm of Isfahan University of Technology in 2015. For this purpose, methanol extracts were prepared from the dried leaves of different cultivars. Total phenolic and flavonoid was measured using spectrophotometry method and measurement of antioxidant activity was done using two model systems, DPPH and ferric reducing power. Essential oil extraction from ground dried flowers was carried out using a Clevenger-type apparatus and essential oil percentage was calculated. The results of analysis of variance showed that Chrysanthemum cultivars were significantly different for all studied phytochemical traits. According to the obtained results, total phenol and flavonoid contents and IC50 values in different cultivars were ranged from 17.63-33.20 mg/g DW, 12.62-53.17 mg quercetin/g, and 54-228 μg/ml respectively. The highest phenolic content was in cultivar “Poya3” (33.20 mg/g DW), whereas the cultivar “Sahand2” (17.63 mg/g DW) contained the lowest value. Also, in terms of total flavonoid content, cultivars “Marmar” and “Sahand 2” had the highest and the lowest flavonoids with 53.17 and 12.62 mg quercetin per gram, respectively. Regarding FTC model system the absorbance rate of different cultivars was variable between 1.30-2.03. Cluster analysis divided all studied cultivars into five groups. The essential oil content ranged from 0.07 to 0.53% (w/w) among the different cultivars. Also, investigated cultivars showed high variation for their essential oil contents. In overall, the results revealed high antioxidant activity in most of the studied cultivars. So, the extract of Chrysanthemum leaves can be introduced as a suitable source of natural antioxidants. Also, in this study, the cultivars Marmar, Atash2 and Erica in terms of phytochemical traits and the cultivar Dorna2 for higher content of essential oil were superior than the others. Therefore, it can be expected that the cross between cultivars “Marmar”, “Atash2” and “Erica” with cultivars in Group V (Derna 2 and Sahand 2) can improve the varieties in this group in terms of biological and antioxidant compounds.

Study of physiological reactions of recombinant inbreed lines (RILs) to drought stress could help to identify the actual drought tolerance mechanisms. In this view a field experiment was conducted to evaluate the effect of drought stress on chlorophyll content , leaf proline content, leaf length, leaf width, leaf area, peduncle length and plant height using 169 RILs, in the two separate simple Latis design with four replications using two moisture regime f normal and water deficit stress. Irrigation regimes performed based on Class A-pan of 70 and 130 mm evaporation from Class -A -pan and moisture content of soil in effected root depth. The RILs were obtained by crossing between a tolerant and sensitive wheat cultivar. The result of analysis of variance showed a significant difference among RILs. Drought stress caused a decrease in the chlorophyll content, leaf width, leaf length, peduncle length, leaf area and increase in the proline content. Although drought stress increased the proline content and decreased the peduncle length and leaf area in both tolerant and sensitive line groups, but these declines in tolerant lines was lower than sensitive lines. Therefore, It may be possible to use the physiological traits comprising proline amino acid content, peduncle length and leaf area as a selection tool for selecting drought tolerant lines in bread wheat.

The wild-relative gene pools of wheat are a rich source of genetic variation for wheat improvement.Karyotypes of eight genotypes of Triticum monococcum subsp. aegilopoides and eight genotypes of Aegilops cylindrica,which grown wild next to each other in different regions in the west of Iran were studied. Root tips were treated in α-bromonaphthalene solution, fixed in chromic acid-formaldehyde fluid, hydrolyzed in 1 N NaOH and staining with hematoxylin. Variation observed in karyotypic formulas of A. cylindrica showing some structural changes of the chromosomes. Aegilops cylindrica classified in 3A class and T. m. subsp. aegilopoides classified in 1A class of Stebbin's classification. Triticummonococcum. subsp. aegilopoides has been suggested to be a relatively old origin because possessing metacentric chromosomes while submetacentric and subtelocentric chromosomes in A. cylindrica suggest a relatively recent origin of the species. The karyotypic symmetry indices used in this study pointed to a much more asymmetric karyotype of A.cylindrica than T. m. subsp. aegilopoides.

Triticale as a man-made cereal is well known for having tolerance to environmental stresses and thus recommended for planting in marginal lands. This experiment was conducted to evaluate the antioxidant enzyme activity of 18 triticale lines comprising 9 doubled haploid (DH) and 9 corresponding advanced lines (F7) and two bread wheat cultivars (Rowshan and kavir) in research farm and laboratory of Agricultural College of Isfahan university of technology during growing season of 2008-2009 under normal and stress conditions. Both the experimental design was equally and simultaneously irrigated until the mid-jointing stage, then irrigation was performed by evaporation from class A evaporation pan. The highest accumulation and antioxidant activities was obtained under stressed condition. The orthogonal comparisons showed that triticale lines and wheat cultivars differed significantly for yield and antioxidant activity with triticale being significantly superior than wheat cultivars under both environmental conditions. Free proline content during water stress condition was increased. As a general conclusion, DH line number 4 by having high proline content and low grain yield reduction under drought stress was ranked as superior drought tolerant genotype.

Mint is one of the most important medicinal and aromatic plants in the world، however، the effects of shading levels on growth and quality of mint accessions have not been well documented. Therefore، the purpose of this experiment was to determine the effects of five shade levels on production of nine mint genotypes. For this purpose a completely randomized design with three replications was conducted during the 2012-2013 growing season in pots in open space in Chah anari field in Isfahan University of technology. Treatments were: (0 (full sun)، 20-30% shade، 40-50% shade، 60-70% shade and 80-90% shade) as different environment and 9 species of Mint: (Karaj، Hamedan and Esfahan (M. longifolia)، Tabas، Ghazvin and 7-1 (M. piperita)، 2-1، 11-3 and Bojnord (M. spicata) intensities. Shoot fresh and dry weights، root fresh and dry weights، leaf total chlorophyll and chlorophyll، a and b and carotenoid contents، essential oil content and yield were measured. The records data were analyzed using combined analyses of data. The highest shoot fresh weights (156/46 g per pots) were was measured under 20-30% shade in Karaj. The highest shoot dry matters (46/60 g per pots) were detected in Esfahan genotype under control (full sun full). The highest root fresh weights (236/47 g per pots) were was recorded for Karaj genotype under 20-30%. The highest root dry matters (73/03 g per pots) were measured for Karaj genotype under 40-50%. The highest chlorophyll b (6/89 mg /g) was measured in Esfahan under sun full. The highest carotenoid contents were was detected in Ghazvin genotype under 20-30% shade level. The highest percent essential oil (1/82%) was recorded in Tabas genotype under 20-30%. The highest essential oil yield essential oil (80/16 mg/g) was registered in Esfahan genotype under 20-30%. Maximum. Under control and 20-30% shade Esfahan genotype، under 40-50% shade Karaj genotype، under 60-70% and 80-90% 3-11 genotype produce highest shoot dry matter. Highest percent essential oil under control level، 20-30% shade and 40-50% shade in Tabas، under 60-70% and 80-90% in 1-2 genotype obtained. Results of this experience showed that measurementd traits were d characters correlated todepends on the genotype and shade laevel and it is possible to selection tolerant genotypes. Esfahani genotype under control and 20-30%، Keraj genotype under 40-50%، 3-11 genotype under 60-70 and 80 to 90% shadings produced the highest shoot dry yield، respectively. Whereas، the highest essential oil content was recorded in Tabas genotype under control، 20-30 and 40-50% shadings and in 1-2 gentype under 60-70 and 80-90% shadings.

The effect of salinity stress on the antioxidant activity of catalase and peroxidase enzymes، relative water content، chlorophyll and carotenoid contents of eight safflower (‍Carthamus tinctorius L.) genotypes differing in salinity tolerance (4 salt tolerant and 4 salt sensitive) were evaluated. This study was conducted using a split plot design arranged as a completely randomized design replicated three times under greenhouse conditions. Salinity treatments were imposed by irrigating with Hoagland solution containing 0، 50، 100، 150 and 200 mM of NaCl in a 30 days period. The results of analysis of variance showed significant effects of genotype، salinity، and genotype × salinity interaction for all the measured traits. Salinity stress led to an increase in chlorophyll and carotenoid contents and peroxidase enzyme activity and a decrease in relative water content and catalase enzyme activity. Salt sensitive genotypes showed less catalase activity under salt treatments. Under salinity stress chlorophyll content of salt tolerant genotypes of safflower was higher than salt sensitive ones. The most salinity tolerant genotype PI-506426 recorded the highest chlorophyll and carotenoid contents under the highest salt stress.

Pomegranate fruit (Punica granatum L.) is a rich source of anthocyanin pigments resulting in vibrant colours and anti-oxidant contents. Although the intensity and pattern of anthocyanin biosynthesis in fruit are strongly influenced by R2R3-MYB transcription factors, little is known about the regulation and role of MYB in anthocyanin pathway of pomegranate. The present study was conducted to elucidate the relationship between the expression of MYB transcription factor and the anthocyanin accumulation during the colour development phase of pomegranate fruits. In this work, R2R3-MYB transcription factor (PgMYB) was isolated and characterized from pomegranate skin through RACE-PCR. The expression of PgMYB gene was monitored in three distinct pomegranate accessions with distinctive skin colour and pattern by semi-quantitative RT-PCR. The results indicated a strong association between skin colour in mature pomegranate fruits with the PgMYB transcripts. The highest expression level of PgMYB gene was observed in Poost Siyah Yazd (dark purple skin) throughout the ripening process. Furthermore, comparison of PgMYB amino acid sequences with those of R2R3-MYB family in grapevine, eucalyptus, peach, cacao, populus and Arabidopsis demonstrated that this protein shares high similarity (75-85% amino acid identity) with their conserved MYB domain. Computational structure prediction of PgMYB showed that the three conserved amino acids (Asn, Lys and Lys) are present in the same position of the MYB domain. It is speculated that PgMYB gene influences the fruit colour and could be used to improve the accumula-tion of anthocyanin pigments in the pomegranate fruit.

Mutation induction is considered as an effective way to enrich plant genetic variation, particularly for traits with a very low level of genetic variation. This research was conducted to assess genetic variation induced by gamma radiation in M2 and M3 mutant lines of canola (Brassica napus L.) by SSR and morphological characteristics and to identify useful mutants in terms of agronomic traits. Sixty-two mutant lines derived from gamma mutagenesis and their wild-type progenitors (‘RGS003’ and ‘Sarigol’ cvs) were used. Twenty-five polymorphic SSR primers were used in this study. Results of cluster analysis based on both morphological traits comprising plant height, days to flowering, days tomaturity, number of pods/plant, number of seeds/pod, 1000-seed weight and seed yield/plant and SSR data revealed a separate grouping of mutant lines from control cultivars. SSR data analysis of mutant lines and controls demonstrated a considerable genetic variation among mutant lines, where 83% of primers generated polymorphic bands with 3.32 alleles per locus. The genetic distance calculated between mutant lines and their controls indicated a significant difference between mutant lines and controls. Although both morphological and SSR markers successfully discriminated mutant lines from controls, SSR primers could further discriminate between the mutant lines derived from the related cultivar. Mutant lines 24 derived from ‘RGS003’ and 16 and 26 from ‘Sarigol’ were considered as superior for breeding canola, which could be utilized in future genetic and breeding programs. Distinct classification of genotypes based on agromorphological and SSR data in the present study implies that morphological and SSR markers reflected different aspects of genetic variation among mutant lines.

This experiment was conducted to evaluate the relationship between photosynthetic characteristics and grain yield in 30 doubled-haploid (DH) lines of Brassica napus in Agricultural Research Station, Isfahan University of Technology, located at 40 km west Isfahan in 2011-12. A randomized complete block design with two replications was used. The following traits were evaluated transpiration rate, stomatal conductance, mesophylic conductance, the stomata carbon dioxide concentration, photosynthesis, photosynthetic rate, water use efficiency (WUE) and grain yield. Analysis of variance showed that DH lines significantly differed for all the traits associated with photosynthesis and grain yield. Results of correlation coefficients between yield and photosynthetic traits of mesophilic conductance (r=0.29) and conductivity (r = 0.3) were significant at 5% level of probability. There was a highly significant positive correlation between yield and WUE (r = 0.33). Highly significant correlation coefficient obtained between photosynthesis and mesophylic conductance (r = 0.99). Moreover, it was revealed that the highest photosynthesis (27.75), stomatal conductance (0.4), water use efficiency (10.16) mesophilic conductance (0.08) belonged to DH line number 9. On the other hand, DH line number 5 possessed the lowest mesophilic conductance (0.009), water use efficiency (1.18) and photosynthesis (3.08). Overall, it can be concluded that the significant differences in all parameters among the canola DH lines may reflect their high genetic diversity associated with photosynthesis and yield potential.

Mutation induction is considered as an effective way to enrich plant genetic variation, particularly for traits with a very low level of genetic variation. The objectives of this study were to evaluate the effect of 1200 GY gamma ray irradiation on morphophenological traits, yield and yield components and to identify useful mutants in two spring rapeseed "RGS003" and" Sarigol" cultivars. The results revealed that there are highly significant difference sa mong mutant lines. Based on the results of phenotypic and genetic correlations, 1000 seed weight had the highest relationship with see dyieldper plant. Stepwise regression analysis also showed that 1000 seed weight was one of the most important traits contributing in seed yield.In viewpoint of the exploitation of the induced variation at morphological traits, M2 lines 9 from RGS003 and 16, 25 and 26 from Sarigol could be suggested as the most desirable lines for canola breeding.

The effects of salt stress on the activity of ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD) enzymes, carotenoid content, the rate of lipid peroxidation (LP) in term of thiobarbituric acid-reactive substances (TBARS) content and grain yield were investigated. Eighteen triticale lines comprising 9 doubled haploid (DH) lines and 9 their corresponding F8 lines as well as two bread wheat cultivars ('Roshan' as a drought tolerant and 'Kavir' as a salt tolerant cultivar), were used. A randomized complete block design with three replications was used for each environmental condition (non-stressed and salt-stressed conditions) at the Research Farm of College of Agriculture, Isfahan University of Technology in a silty clay loam soil in 2008-2009. Both salt stressed and non-stressed experiments were irrigated with water having EC of 1 dS m-1 until mid-jointing stage (43 growth stage of Zadoks scale), and afterward salt-stressed experiment was irrigated with saline water containing 175 mM NaCl and EC= 16 dS m-1. Salinity led to an increase in the enzymes activities and LP and decrease in carotenoid content in the leaves of both triticale and wheat genotypes. An inverse and significant relationship between grain yield loss due to salinity stress with carotenoid content was observed under salinity stress (r = -0.54*). Under both conditions, negative and significant correlations (r = -0.61**) were observed between grain yield and LP. The orthogonal comparison between triticale line and wheat cultivars revealed the superiority of triticale lines for the production of antioxidants and less LP in triticale than wheat under both environmental conditions, which may be related to the development of relatively higher salt tolerant in triticale.

This research was conducted to validate and fine map the region attributed to salinity tolerance on chromosome1 in rice (Saltol) at International Rice Research Institute (IRRI) during 2005 to 2007. A major effect QTL (Saltol) which is responsible for Na+ and K+ uptake and their ratio was identified using F8 recombinant inbred lines (RILs) of Pokkali/ IR29 cross on chromosome 1. This QTL explained around 64.3 to 80.2% of the phenotypic variation for the mentioned traits. Fine mapping was done using 10 SSR and EST-SSR markers and near isogenic lines (BC3F4), derived from IR29 × Pokkali that were produced for this trait. Random BC3F4 individuals were genotyped and phenotyped under two different electrical conductivities at seedling stage. QTL responsible for salinity tolerance at both ECs, were found in the same place in Saltol region, which explained 18 and 24% of the phenotypic variation for SES scores, respectively. According to the present results, possible location of Saltol was found in the interval around 1.2 cM on chromosome 1 that could physical map. It was around 350Kb. This QTL was mapped at the intervals of RM8094, RM3412 and CP6224. Therefore, molecular breeding for salinity tolerance in Iranian genotypes could be done using the mentioned markers.

The influence of late-season drought stress on grain yield, its components and some other morpho-physiological traits was evaluated using 151 F3 families obtained from crossing a drought tolerant genotype with a drought susceptible genotype at Research Farm of Isfahan University of Technology in 2003-2004. Two separate randomized complete block designs each of which having two replications allocated to each of moisture stress and irrigated (non-stress) environments. Drought stress significantly affected grain yield, its components, harvest index and relative water content (RWC) traits. Analysis of variance of combined data revealed significant differences among the environments for the traits that related to reproductive stage. The genetic and phenotypic correlation coefficients between grain yield and most of traits such as RWC and excised leaf water retention (ELWR) were significant. Based on stepwise regression analysis, biological yield and harvest index were the most efficient traits in explaining the grain yield variation under normal and stress environments, respectively, Factor analysis of data from the two environments indicated that components were related to phenologic characters, potentional of plant production, harvest index and yield components, plant height and physiological traits. The amount of variation explained by these components varied for two environmental conditions where yield components, plant height and physiological traits had a high impact under stress environment. Cluster analysis of families based on all of traits for two environments defined desirable clusters. This cluster divided families into five groups each of which desirable for a particular trait such as high or low grain yield in stress environments, early maturity, late maturity, high RWC and high ELWR.

Variability of seed storage protein electrophoretic patterns revealed by SDS-Polyacrylamide gel electrophoresis and their possible relations with some morphological and phenological characteristics were studied using 193 accessions from Iran Mungbean (Vigna radiata</em> L. Wilczek) Collection. Seed protein electrophoresis revealed six different patterns that were different in two albumin and four globulin subunits with molecular weights of 23500-34000. Pattern types 1 and 2 had a considerable frequency but pattern types 3, 4, 5 and 6 had low frequencies and probably had developed recently in mungbean evolution process. Cluster analysis of countries and cities using the frequencies of albumin and globulin subunits showed no relation between geographical diversity and similarity distances. The correlations of morphological traits and albumin and globulin subunits indicated a relationship between G1 and G2 subunits with 1000 seed weight and days to beginning of maturity. Therefore, selection based on protein patterns at preliminary stages of breeding programs might be effective in increasing seed yield together with earliness.

In vitro</em> salt tolerance of 28 cultivars of durum wheat with native and exotic origins was investigated, using MS medium containing sodium chloride. The resulting calli were subjected to 8 salinity levels including 0, 0.3, 0.6, 0.9, 1.2, 1.5 and 1.8 percent NaCl (w/v). Donor plants of explant (immature embryo) were grown in a recirculating hydroponics and pots in a greenhouse as well as in the field. Assessment of calli was conducted after 0, 8 and 16 days after subculture of calli into the NaCl-contained medium. Callus growth rate, relative callus growth rate and percentages of callus necrosis were measured, using a 8 × 28 factorial experiment layout in a completely randomized design with 3 observations per treatment and 3 replications. Results of analysis of variances showed that among the criteria, relative growth rate of callus was the most reliable, while callus growth rate as not being quantitatively measured, was less devoted. Results of this study revealed that 'PI 40100' and 'Dipper-6' were superior genotypes for in vitro</em> salt tolerance. The high relative callus growth rate and less callus necrosis of these cvs. may indicate their superior genetic potential for in vitro</em> salinity tolerance.

Immature embryo culture response of 28 durum wheat (Triticum turgidum</em> var. durum</em>) cultivars was studied using MS medium in Tissue Culture Laboratory of College of Agriculture, Isfahan University of Technology. Donor plants were grown in a recirculating hydroponic system and pots in a greenhouse. Regenerated immature embryos were recorded at 2, 4, 8 and 16 days after inoculation. Assessment of durum wheat cultivars for immature embryo culture was conducted by percentage and rate of regenerated embryo, using a split plot design arranged in completely randomized design with 5 replications. The analysis of variances showed that there were highly significant differences among cultivars for plant regeneration capacity. The highest potential and rate of embryo regeneration (two days after inoculation) were observed in “Shahivandi” which is a native cultivar of west Iran. “Awl1/Sbl4” with a mean of 48.5%, “Hagla” and “Ofen/Kil” with a mean of 80% have the poorest and the best mean of regeneration during the recording period, respectively. The high regeneration potential is important in view of reducing the time constrain and somaclonal variation in a breeding program.