فهرست مطالب قدرتاللهسعیدی

Drought is one of the most important environmental factors affecting plant growth. The double haploid method is one of the most common breeding methods in wheat. Using old cultivars in cross-breeding programs can be effective for restoring genes lost during evolution. In this study, in order to evaluate the genetic diversity and to select the drought-tolerant introgression wheat lines, 151 double haploid (DH) lines (derived from cross of old and modern cultivars) were evaluated under two moisture conditions (non-stress and drought-stress) in field. Considerable genetic variation was observed among DH lines for most of the traits indicating that selection for these traits can be effective to develop lines with higher performance or for specific purposes. The effect of drought stress was significant for most of the traits. For example, drought stress reduced grain yield by 40%. Comparison of old and new parent genotypes showed that the new parent was earlier in maturity, dwarf and had higher grain yield, yield components and harvest index. Transgressive segregation was observed for most of the traits indicating the possibility of selection for superior lines. In both moisture condition, plant height had the highest narrow sense heritability (46%) and leaf relative water content had the lowest one (12%). Grain yield had negative correlation with day to flowering indicating that selection for earliness can improve drought tolerance. According to the results of tolerance indices and biplot of principle component analysis, superior lines were identified. For example superior lines for grain yield, early flowering and higher harvest index were recognized for future studies.

Emmer tetraploid hulled wheats are considered as the ancestor of modern wheat and have considerable potential for durum wheat improvement, especially in terms of grain protein content. To investigate the response of emmer and durum wheats to different levels of nitrogen fertilizer, eight durum and four emmer genotypes were evaluated in the field during 2017 cropping season. The experiment was conducted as split plot using randomized complete block design with three replications. In this setting the main factor was four levels of urea fertilizer (0, 50, 150 and 200 kg ha-1) and the 12 wheat genotypes were considered as the sub-factors. The results of analysis of variance showed that the effect of nitrogen fertilizer levels on days to physiological maturity, grain protein percentage, nitrogen percentage and nitrogen concentration in grains was significant (p<0.01). The effect of genotype was also significant (p<0.01) for all the measured traits. Emmer genotypes had higher means for spike number per square meter, grain protein, nitrogen concentration in grain and protein percentage compared to durum wheat genotypes. Based on these findings, emmer wheat can be considered as a rich gene resource for improvement of durum wheat, especially the grain protein.

Regarding the insufficient water resources, developing of cultivars with high tolerance to water deficit can be very effective to optimize water consumption. To identify maize hybrids with higher tolerance to water deficit, 52 single cross hybrids were field evaluated according to a randomized complete block design with three replications in each irrigation regime. The hybrids were produced through crossing of 13 inbred lines from CIMMYT germplasms with four testers of A679, K166B, K18 and MO17. Two check hybrid varieties (KSC704 and KSC705) were included for comparison.  Two irrigation regimes including a normal and a deficit irrigation based on 65% water requirement of plants were applied during two growing seasons of 2014 and 2015 at the Research Station of the Agriculture and Natural Resources of Kermanshah Province. The drought tolerance and sensitive indices were calculated based on grain yield (t/ha) of hybrids at two irrigation regimes. The results of analysis of variance showed significant differences among the hybrids for grain yield and all the indices. The seed yield of hybrids in normal irrigation condition varied from 8.7 to 15.2 t/ha. This range was 4.9 to 10 t/ha in deficit irrigation condition. The cluster analysis classified the hybrids in three distinctive groups. It was recognized that hybrids number 51, 18, 45, 48, 21, 27, 23, 19, 20, 28, 38, 14 and 26 were superior than the others in terms of water deficit tolerance and grain yield. The PCA analysis showed that hybrids number 48, 45, 18 and 51 with high yield potential can be introduced as more promising ones for maize production in normal irrigation condition. However, hybrids 19, 23, 27, 25, 21, and particularly 9 were recognized more suitable for maize production in water deficit condition.

Wild relatives of safflower have high potential of  hybridization with cultivated safflower and have a high tolerance to biotic and abiotic stresses, especially drought stress. This study was conducted to investigate the effect of drought stress on the physiological traits and their relationship with seed yield in F4 lines drived from interspecific hybridization of safflower. For this purpose, 12, 13 and 14 lines derived from three crosses of Carthamus tinctorius × Carthamus palaestinus (TP), Carthamus tinctorius × Carthamus oxyacanthus (TO) and Carthamus palaestinus × Carthamus oxyacanthus (PO) with 3 parental species (total 45 lines) were evaluated separatly under both normal irrigation and drought conditions. In the first study, F4 lines were evaluated for understanding the physiological mechanisms of drought tolerance, and in the second study, the effect of selection for seed yield in F3 on these traits in F4 was investigated. The results of the first study showed that TP crosses had higher seed yield than the other two crosses under normal irrigation condition, but there was no significant difference among the crosses under drought stress condition. The parental species showed significant differences for relative leaf water content, proline content, malondialdehyde, chlorophyll a and chlorophyll fluorescence. However, interspecific populations showed no significant differences for most of these traits under drought stress condition. These results may indicate the transfer of resistance genes from wild species to the cultivated safflower. The results of the second study showed that TP, PO and TO populations were different in terms of physiological traits, and it was revealed that selection efficiency was depend on the type of studied population. Selection in the TP population, which was derived from crossing between the cultivated species and wild species  of C. palaestinus, showed higher efficiency due to selection than the TO and PO populations in which  C. oxyacanthus was one of their parents.Therefore, with considering the physiological traits and seed yield, TP population was recognized as the best population for breeding programs.

In order to evaluate drought tolerance of some safflower genotypes, an experiment was conducted at the Research Farm of Isfahan University of Technology in 2016 and 2017. In this study, 18 safflower genotypes selected from different local populations along with 2 exotic cultivars and one local population (21 genotypes) were separately evaluated at two normal (non-stress) and water deficit (stress) irrigation regimes, using a randomized complete block design with two replications. Drought tolerance and susceptible indices were calculated based on the seed yield. The results showed that there was significant differences among genotypes for seed yield. The genotypes M420 (4703 Kg/ha) and C116 (2723 Kg/ha) had the highest and lowest seed yield, respectively in normal irrigation condition, however, genotypes of A2 (2906 Kg/ha) and Arak2811 (1373 Kg/ha) had the highest and lowest seed yield, respectively in water deficit condition. Based on the correlation coefficients between indices and seed yield under both irrigation regimes, the indices of MP, GMP, STI, MpSTI and MsSTI were recognized as the best ones for identification of drought tolerant genotypes in safflower. The graphic biplot and cluster analysis indicated that genotypes M420, S149, K21, K12, E2428, E2417, AC-Stirling and A2 were more tolerant genotypes to water stress.

This experiment was conducted at the Research Farm of Isfahan University of Technology, Najafabad, Iran in 2014 and 2015 to evaluate drought tolerance indices of some sesame (Sesamum indicum L.) genotypes. In this study, 21 sesame genotypes isolated from different local populations along with seven exotic cultivars were evaluated at two irrigation regimes, using a randomized complete block design with two and three replications in the first and second years, respectively. The normal and water deficit irrigation regimes were determined based upon the depletion of 60% and 90% of soil moisture content, respectively. The results showed that the effect of irrigation regimes was significant (p<0.01) on seed yield. Averaged over two-years, mean of seed yield was 2186 kg ha-1 and 1231 kg ha-1 in normal and water deficit irrigation conditions, respectively. Based upon the data of two years, the genotype Shiraz 5 had the highest seed yield in normal irrigation conditions, however, genotypes Markazi 1 and Shiraz 5 had higher seed yield in water deficit condition. Investigation of different indices of tolerance and sensitivity to drought stress (TOL, SSI, STI, MP, GMP, HARM, DRI, SNPI, SSPI and ATI) showed that STI, MP, GMP, HARM and SNPI were more suitable indices to recognize drought tolerant sesame genotypes. Based upon these indices obtained from the data of two years, genotype Shiraz 5 had the highest tolerance and more productivity and genotype China had the highest sensitivity to drought stress with less potential of productivity.

This study was performed in order to evaluate the drought tolerance of some safflower genotypes in a field experiment carried out at the research farm of Isfahan University of Technology located at Lavark, Najaf-Abad, Iran (40 km south west of Isfahan, 32º 32´ N, 51º 23´ E, 1630 m asl). In this study, five genotypes including A82) interspecific hybrid), landrace Kooseh, Goldasht, C111 and Ac-stirling were evaluated in a randomized complete block design with three replications at two moisture levels (normal and 90% water-depletion), separately. Seven drought tolerance indices including Stress Tolerance Index (STI), Tolerance Index (TOL), Stress Susceptibility index (SSI), Mean Productivity (MP), Geometric Mean Productivity (GMP), seed yield in stress (Ys) and non-stress (Yp) environments were calculated for each genotype based on seed yield under stress and normal conditions. The results analysis of variance showed that there were significant differences among the genotypes for all traits. The drought stress had significant effect on head diameter, number of heads per plant, number of seeds per head, seed weight per head and seed yield. Mean comparisons showed that control genotypes were significant differences for all studied traits except seed weight per and seed yield traits with the genotype A82 under non stress and stress conditions. Principal component analysis (PCA), indicated that the first and second components justified 91% of variations between drought tolerance indices. First vector showed 67% of the variations and was recognized as yield potential component and drought tolerance indices (MP, GMP, STI) and the second rector justified 24% of total variations which would be named as “drought susceptible components (TOL and SSI indices). Biplot analysis also indicated that STI, MP, GMP were more reliable indices to identify drought tolerant safflower genotypes and discriminated Goldasht genotype and genotype A82 as the most drought tolerant. The indices STI, GMP, MP identified the Goldasht  and A82 genotype as a drought resistant genotype and this genotype was obtained from interspecific crosses between cultivated safflower (Carthamus tinctorius L.) and wild species (C. oxyacanthus). This genotype had the highest grain yield under stress and non-stress conditions. Therefore, it could be used in safflower breeding programs to improve drought tolerance.

The use of appropriate selection methods are important to increase yield in breeding programs. Utilization of selection indices is one of the most effective method for selection of superior genotypes to improve the complex traits such as seed yield. In order to evaluate the efficiency of different selection methods, 63 families of two F3 populations derived from inter-specific hybridization of Carthamus tinctorius ×Carthamus oxyacanthus (IO) and Carthamus palaestinus × Carthamus tinctorius (IP) were evaluated under two moisture environments (normal and drought-stress) at the research farm of Isfahan University of Technology during 2016. The Smith-Hazel 1, Smith-Hazel 2 and Pesek-Baker indices were measured based on the traits entered in step-wise regression model. The results indicated that under normal conditions, Pesek-Baker index was more effective than the Smith-Hazel 1 and Smith-Hazel 2 and was also more efficient for the selection of superior genotypes in IP population. Also, the Smith-Hazel 1 and Smith-Hazel 2 indices were more effective than Pesek-Baker index under drought-stress conditions in this population. Smith-Hazel 1 and Smith-Hazel 2 indices were more effective than Pesek-Baker index in IO population at two moisture environments. Efficiency of selection in IP population was more than IO population, thereby it can be used to develop superior genotypes in breeding programs. Since the C. palaestinus have less undesirable characters compared to other wild parents, it may be suitable source for transferring desirable genes to the cultivated species.

Wild relatives of safflower are considered a useful source of desirable genes to develop improved cultivars for important agronomic and physiologic traits such as drought and salinity tolerance as well as increasing seed yield. Among wild species, cross compatible species are highlighted to obtain high genetic gain in next generations. In the present study, Carthamus tinctorius, C. palaestinus and C. oxyacanthus were crossed with each other and three segregating populations were developed. Single plant selection (SPS) and stress tolerance index (STI) were jointly employed in F4 and F5 generations for these three populations. Genetic gain was obtained under both water stress and non-stress conditions for several traits including seed yield. Genotypes from A and D groups of the three-D plots in F4 generation were repeated exactly in the same groups in the three-D plots of F5 generation indicating a very high selection efficiency. Response to selection in different interspecific populations under water stress and non-stress conditions identified suitable criteria for improving seed yield. High response to selection plus high broad sense heritability for several traits indicated the contribution of genetic variation more than environmental factors. Number of seed per capitulum, capitulum diameter, capitulum weight, 100-seed weight and number of branches had high narrow-sense heritability, and could be suggested as important and key traits for safflower breeding programs in water limited conditions. It is concluded that combining STI with SPS method in safflower interspecific breeding may efficiently identify superior genotypes in the early segregating generations under water stress and non-stress conditions.

Bromus danthoniae Trin. is an annual grass species which grows mainly on dry grassy rocky mountain slopes and grassy steppe, and is grazed by many herbivores and recognized as a useful pasture plant. The chromosome number, morphological and anatomical traits of 82 genotypes of B. danthoniae belonging to three sub-taxa were investigated. Twenty-seven quantitative and 20 qualitative morphological traits were evaluated. The results of analysis of variance showed that B. danthoniae genotypes varied significantly for all quantitatively tested traits. Based on cluster analysis, the genotypes were divided into four groups which mostly corresponded to their subspecies identities. According to correlation analysis, lemma length had strong positive correlations with other traits such as awn length (r=0.55**), lemma width (r=0.72**) and caryopsis length (r=0.84**). In addition, lemma width was significantly correlated with the traits like floret number per spikelet (r=0.47**) and caryopsis length (r=0.58**). Based on factor analysis, the first three factors encompass about 51% of total variation. Overall, lemma length and lemma width were the two reliable traits for morphological investigations in this species. The results of chromosome counting showed that B. danthoniae subsp. danthoniae and B. danthoniae var.lanuginusos Roshev. were diploid (2n=2x=14) whereas B. danthoniae subsp. pseudodanthoniae (Drobov) H. Scholz was tetraploid (2n=4x=28). The results of leaf surface anatomy showed that tetraploid genotypes had larger stomata but lower stomatal density than the diploid ones, thus a comprehensive relationship between genome size and guard cell size cannot be ruled out as a plausible explanation for differentiating the ploidy levels. The high morphological variations among the B. danthoniae genotypes explain the habitat distribution of this species and enable us to incorporate this knowledge into practice by exploiting the variation for improvement of pasture production.

Bromus danthoniae Trin. is an annual grass species that is well adapted to harsh climates and could be considered as an important genetic resources for tolerance to environmental stresses such as salinity. In this study, 24 genotypes collected from Ilam, Kurdistan, Kermanshah (non-saline areas) and West Azerbaijan (saline area: shores of Uremia Salt Lake) provinces of Iran were investigated at the germination stage under salt treatments with concentrations of 0, 60, 120, 180, 240 and 300 mM sodium chloride. Germination percentage, germination rate index, seed vigor, root length, shoot length and seedling fresh and dry weights were measured. In addition, the relationship between the percentage of germination in 300 mM sodium chloride and the survival rate (%) after four weeks in 350 mM sodium chloride at the vegetative stage was evaluated. The results of analysis of variance showed that salinity treatments caused significant reductions in all the studied traits. Genotypic variation and the interaction of genotype × salt treatments were also significant. Genotypes USLN3 and KER4 were found to be the most tolerant and sensitive genotypes to salinity stress, with 13% and 98% reduction in germination percentage at 300 mM NaCl, respectively. Cluster analysis divided the genotypes into three groups, with one group containing only tolerant genotypes from Uremia Salt Lake, another one comprising only sensitive genotypes from non-saline regions, and the third one containing genotypes from both regions. The correlation between the germination percentage and the survival rate at the vegetative stage was not significant, indicating that different mechanisms are, perhaps, responsible for salinity tolerance at the germination and vegetative stages in B. danthoniae.

In order to study seed yield components and agronomic traits in some F3 families of flax (Linum usitatissimum L.), this experiment was conducted in 2014 at the Research Farm of Isfahan University of Technology, Isfahan, Iran. In this experiment, 50 families of F3 generation derived from different crosses were evaluated in a randomized complete block design with two replications. The results showed that there were significant differences among the families for all yield components, seed yield per plant and seed yield per plot. The means of seed yield per plot for the families ranged from 622 (family of 32) to 2212 kg/ha (family of 37).The range of days to maturity, plant height and seed yield per plant in families was 82 to 97 days, 38 to 71.3 cm and 1.27 to 3.71 g, respectively. The coefficient of genetic variation for most of the studied traits were slightly smaller or very close to those of phenotypic ones, indicating that most of the observed variation for these traits were due to genetic factors, and thus a moderate to relatively high broad-sense heritability (45.7 to 86.83%) was observed for those traits. The highest and lowest genetic variations were observed for seed yield per plot and days to flowering, respectively. Cluster analysis based on the agronomic traits separated the families into 4 distinct groups, in which the 2nd and 4th groups had the highest mean of seed yield components and, thus seed yield per plot. Generally, the results showed that there was high genetic variation for the studied traits including seed yield and its components and selection can be effective to improve these traits.

In order to investigate the possible influence of seasonal variation on the percentage of seed oil and total phenolic content in seeds and leaf of safflower, three populations (19 accessions) including 6 cultivars of cultivated species (Carthamus tinctorius), 4 genotypes of wild species (C. oxyacanthus) and 9 genotypes of F5 generation derived from inter-specific cross (C. tinctorius× C. oxyacanthus) in two sowing dates, were evaluated. The results showed the effect of planting dates was significant on the percentage of seed oil and total phenolic content of seeds (p

Breeding based on selection indices is an effective method for improving complex traits such as yield. To assess the efficiency of different selection method, 83 exotic along with 17 Iranian safflower genotypes were evaluated at the research farm of Isfahan University of Technology using 10×10 simple lattice design with three replications in 2011. In this study, the selection indices of Smith-Hazel and Pesek-Baker were determined based on the number of capitulum per plant, number of seeds per capitulum and 1000-seed weight. Also response to selection and relative selection efficiency were estimated for traits under study and seed yield. The highest estimated selection efficiency for genetic improvement of seed yield was obtained via selection for number of capitulum per plant. Therefore, this trait can be used as an appropriate selection criterion for improvement of seed yield. The results showed that seed yield was highly correlated with each of these indices and the estimated efficiency of indirect selection via these indices was relatively high. Thus, it seems that these selection indices can be effectively used for seed yield improvement. Results of present study showed that the efficiency of Smith-Hazel indices for simultaneous improvement of number of capitulum per plant, number of seeds per capitulum and 1000-seed weight was higher than that of Pesek-Baker index.

Bilehar or Kandal koohi (Dorema aucheri) which belongs to umbeliferae family is an endemic species of Iran. In respect to the extinction risk of this valuable species, until now no study has been performed to evaluate the effect of climate features on different traits in D. aucheri populations in different geographical areas.
The goal of the study was to investigate phytochemical, morphological and antioxidant variation of Bilehar (Dorema aucheri) populations cultivated in different environmental conditions.
The experiment was conducted in a randomized complete block design in three replicates in November 2014 in three different areas. The total phenolics and flavonoid content were determined colorimetrically. The antioxidant activity of extracts were measured using two model systems, DPPH free radical scavenging (DPPH) and reducing iron (FTC). The essential oil was extracted based on hydro- distillation. To investigate the effect of environmental factors on phytochemical characteristics, Canonical Correlation Analysis (CCA) was applied.
The results revealed the presense of significant differences between populations and various locations for the studied characteristics. Gorgue and Dishmook populations possessed the highest and the lowest amount of phenolics and essential oil in Margon and Isfahan provinces, respectively.
Finally, Gorgue possessed the best performance among all populations in respect to the phytochemical and morphological traits in all provinces, so, further studies are suggested to be done for the domestication of this plant population.

Safflower is a crop native to Iran and could be improved in plant breeding programs by inter-specific crosses. This study was conducted to evaluate genotypes of safflower derived from interspecific hybridization for the relationships between some agronomic traits and yield components. The genotypes were planted according to a randomized complete block design with three replications at the research farm of Isfahan University of Technology in 2011. Seed yield per plant ranged from 41.6 to 49.14 gr. The hybrid genotype 4 (F6) had the highest mean of seed yield per plant. The results of the correlation analysis showed that 1000-seed weight and head diameter were the most correlated with the seed yield per plant. Stepwise regression results showed that the 1000-seed weight and head diameter were the most important factors determinants of grain yield per plant and justified 61 percent of yield variation. The path coefficients analysis also showed that, 1000-seed weight, head diameter and number of heads per plant were considered as the first order variables and accounted for 56% of total variation of yield. The results also indicated that both traits of 1000-seed weight and head diameter could be considered as selection criteria for increasing safflower yield in breeding programs.

Safflower (Carthamus tinctorius L.) is cultivated in a wide range of geographical conditions in the world from Africa to Europe، India and China. Previous studies have shown that diversity in indigenous Iranian germplasm is limited for some traits; therefore germplasm collections from other origins need to be considered. An experiment was conducted to evaluate agronomic and morphological traits of 100 Iranian and exotic safflower genotypes during 2011- 2012 at the Research Farm of Isfahan University of Technology، Isfahan، Iran، using a simple lattice design of 10 × 10. The results of analysis of variance showed that the differences among genotypes were highly significant (p < 0. 01) for days to flowering، seed yield، plant height، number of heads per plant، number of seeds per head، 1000-seed weight، oil content and harvest index، indicating high variability in the studied germplasm. The highest and lowest heritabilities were observed for 1000-seed weight and seed yield، respectively، indicating that indirect improving for seed yield would be more beneficial. Genetic and phenotypic correlation coefficients showed that number of heads per plant، number of seeds per head and harvest index had significantly positive correlations with seed yield. The results of stepwise regression and path analysis showed that number of heads per plant، number of seeds per head and 1000-seed weight are the most important components of seed yield، among which، number of heads per plant had the greatest direct positive effect on seed yield. These traits could be used as criteria for indirect selection in safflower breeding programs. Factor analysis recognized three factors which explained 72. 56 percent of total variations. These factors were defined as phenological، physiological source and efficiency factors. Cluster analysis based on the agronomic and morphological traits grouped the genotypes into three clusters. Iranian accessions were clearly discriminated from other genotypes and allocated in the group three. In conclusion، the results indicated that there was a broad genetic diversity among Iranian and foreign germplasm which can be exploited in breeding programs.

In order to study the relationships among agronomic traits and yield components in some breeding lines of safflower (Carthamus tinctorius L)، this experiment was conducted in a randomized complete block design with three replications in 2009، at the Research Farm of Isfahan University of Technology located in Falavarjan، Isfahan، Iran. Twenty genotypes of safflower were planted in this experiment and days to emergence، days to the commencing of flowering، 50% flowering and maturity، plant height، branches/plant، percentage of infected capitulum to safflower fly، seed yield، capitula/plant، seeds/capitulum، 1000 seed weight، capitulum diameter، seed weight/capitulum and seed oil content were evaluated. The results of analysis of variance showed that there were significant differences among the genotypes for all of the studied traits، except for days to emergence. Genetic and phenotypic correlation coefficients showed that capitula/plant، seeds/capitulum and capitulum diameter were the most important seed yield components and they had the highest positive correlations with seed yield. However، seed weight showed negative genetic and phenotypic correlations with seed yield. Based on the regression analysis، capitula/plant along with capitulum diameter accounted for 66% and 74% of the seed yield variation، respectively. Path analysis showed that capitula/plant had the most positive direct effect on seed yield with no significant indirect effect through the other traits. Also، seeds/capitulum had a high direct and positive effect and considerable indirect effect via number of capitula/plant on seed yield.

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.

safflower species. Iranian Journal of Crop Sciences. 16(3): 165-180. (In Persian). Safflower with high grain oil quality and good tolerance to environmental stresses can be important for oil seed production. A good source of useful genes for improving cultivars of this plant species is its wild relatives. This experiment was conducted to assess the genetic variation and tolerance to drought stress in F3 families derived from a cross between domesticated (Carthamus tinctorius L.) and wild (C.oxyacanthus L.) safflower species using a randomized complete block design with three replications under drought stress and non stress conditions. High heritability was observed for the studied traits including: days to flowering, days to physiological maturity, plant height, number of branches per plant, number of head per plant, number of grain.head, 1000-grain weight and grain yield. The highest genetic coefficient of variability belonged to grain yield per plant 41% and 36% in stress and non-stress conditions, respectively). Transgressive segregation was also observed among the F3 families in both directions and both conditions for most of the traits. The presence of significant genotype by environment interaction for the studied traits implied different reactions of families to drought stress and non-stress conditions. Family 36 with high yield in both stress and non-stress conditions and low reduction in grain yield under drought stress was identified as the superior family. Result of this experiment indicated that there are possibility of improving drought tolerance in safflower genotypes using inter-specific corssing with Carthamus oxyacanthus L.

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.

The selection of high yielding and stress tolerance plant genotypes with the highest water use efficiency and productivity is one of the most important tools for field water management in arid and semi-arid regions. This study was conducted to identify drought tolerant flax families with the highest irrigation water productivity (IWP) among a population of 119 F3 families derived from a cross between KO37 (an Iranian flax cultivar) and SP1066 (a Canadian cultivar) under water stress and non-stress conditions. The mean comparison showed that the segregating population had sufficient diversity for drought tolerance and grain yield. Finally, based on IWP, families no. 38, 39, 72, 74 and 119 that had high IWP in both stress (moderately 0.47 kg/m3) and non-stress (moderately 0.63 kg/m3) conditions, were introduced as the most drought tolerant families. The results of triplot analysis based on STI index and IWP in stress and non-stress conditions introduced the families as the most favorable families. The advanced generations derived from the families can be used in the future breeding programs to improve and produce high yielding-drought tolerant inbred lines in linseed in order to increase water use efficiency and to economize water resources in the field management.

Evaluation of genotypic and phenotypic variation and heritability of important agronomic traits in segregating populations is one of the principles of breeding for quantitative traits. This study was conducted to assess the genotypic and phenotypic variation and drought tolerance in the F3 families derived from a cross between KO37 (Iranian linseed cultivar) and SP1066 (Canadian linseed cultivar) at Research Farm of Isfahan University of Technology, Isfahan, Iran, in 2011 and 2012. Results showed that under drought stress the highest reduction in the number of seed per plant, yield per plant and Irrigation Water Productivity belonged to SP1066 parental genotype. Combined analysis, the highest phenotypic and genotypic coefficients of variability (19% and 25%, respectively) belonged to number of seed per plant, yield per plant and number of capsules per plant. The highest heritability was estimated for 1000-seed weight (86%), plant height (85%) and days to 50% flowering (81%). The presence of high genotypic and continuous variation and also transgressive segregation for studied agronomic traits and IWUE in F3 families under both conditions indicated that the F3 population or its advanced generations can be used in mapping, identification of QTL related to important agronomic traits and increasing drought tolerance in linseed.

To characterize the distribution of melanin producing Medicago-nodulating rhizobia in western and north-western of Iran, 982 Sinorhizobium isolates were trapped from a combination of three alfalfa populations (Hamedani, Nikshahri, Kodi) and soil samples from eight sites across Kurdestan, Kermanshah, Eastern Azarbayjan and Lorestan provinces. All rhizobial isolates were examined for their ability to produce melanin (Mel+). According to the results, 24.1% of them were Mel+, as well as the reference strain S. meliloti GR4. Analysis of melanin production revealed more melanin producing isolates among different sites in comparison of different cultivars. Therefore, it can be concluded that the influence of field soil type in dominance of melanin producing strains is more than the host cultivars. The presence of 456 bp amplified fragment using primers designed from the mepA gene in 30 strains of rhizobial strains and its absence in 20 other strains was in accordance with the results of melanin production in the medium, showing that all strains producing melanin contained mepA gene. Multiple sequence alignment revealed that the sequence of mepA gene in S. meliloti is conserved, while this sequence in S. medicae had limited changes.

This study was carried out to evaluate the genetic diversity of the breeding lines isolated from the sesame landraces. Seventy genotypes were evaluated in randomized complete block design with two replications in 2008. The results showed that there were significant differences among the genotypes for all of the studied traits such as days to maturity، plant height and seed yield. There was no difference between the phenotypic and genetic coefficients of variations for most of the traits، thus it was concluded that the majority of their observed variations was due to the genetic factors. The grain yield of the genotypes ranged from 1089 to 4650 kg/ha. One of the breeding line isolated from Birjand landrace had the highest mean of days to maturity (170 days) and Yekta genotype had the lowest mean for this trait (118 days). The range of plant height among genotypes was 123 to 179 cm and the mean of capsule per plant was ranged from 46 to 181. Branches per plant had the highest broad-sense heritability (81. 1 %) and the estimated broad-sense heritability for grain yield was 75. 5%. Cluster analysis classified the genotypes in three distinct groups and there were significant differences among these groups for all of the traits، except days to maturity. Genotypes classified in the second group had the most capsule per plant and grain yield and they can be used for genetic improvement of this trait. Meanwhile genotypes of the first group can be used for genetic improvement of plant height and branches per plant.