پژوهشنامه اصلاح گیاهان زراعی
پیاپی 20 (زمستان 1395)

In order to study genetic diversity of different wheat inbred lines and grain yield modeling as well as selection of elite lines, 305 wheat lines derived from Roshan × Falat cultivar along with their parents as well as two check (Mahdavi and Shahpasand) cultivated in research field of Sahid Bahonar university of Kerman in augment design, on growing season of 2013-2014. Result of genetic and phenotype correlation has high coincidences together that shown infer low influence of environment error to relationship between evaluated traits. According to results of correlation analysis significant correlation was seen between grain yield and most of evaluated traits. Results of ANOVA of evaluated traits showed non-significant difference between check varieties in different incomplete blocks, this showed the homogeneity of experiment field. Stepwise regression model showed%81 changes of grain yield is justified by 1000 grain weight, number of grain per single plant, number of fertile tiller, plant hight and awn length. By factor analysis for the 13 evaluated traits shown%65 of variation in grain yield is justified by four factors, cluster analysis categorized the lines into three groups, the dendrogram revealed lines the third group of lines white the second group have significant difference. Evaluation of grain yield potential and phenotypic diversity measured traits lead to selection 40 better inbreed lines in this research. Results of this research showed number of grain per single plant, number of fertile tiller, grain filling period and awn length would be recommended traits for indirect selection for improvement grain yield.

In order to study tolerance of durum wheat (Triticum durum) lines to drought stress and also evaluating stress tolerance indices, an experiment based on randomized complete block design with four replications was conducted under two rain fed and supplementary irrigation conditions at Gachsaran station during 2011-2012 cropping season using 20 durum wheat lines. Results of combined analysis of variance for seed yield showed significant differences (p≤0.01) between lines and interaction between lines and environment. The yield based indices were calculated in rain fed and supplementary irrigation conditions. With considering of significant positive correlation between grain yield in the rain fed condition (YS) with geometric mean productivity index (GMP), mean productivity index (MP), stress tolerance index (STI), yield index (YI), drought response index (DRI), drought resistance index (DI), harmonic mean (HM) and modified stress tolerance index (K1STI), these indices were suitable criteria for identification of drought tolerant lines. Also, tolerance index (TOL), yield stability index (YSI), stress susceptibility index (SSI), relative drought index (RDI), abiotic tolerance index (ATI), stress susceptibility percentage index (SSPI) and stress non-stress production index (SNPI) didn’t have important role in the differentiation of lines. Grouping of lines using cluster analysis method showed that the lines 3 and 13 had high yield and were tolerant rain fed condition and the lines 7 and 18 were sensitive to rain fed condition. The results from grouping of lines using three dimensional graphs based on yield in rain fed and supplementary irrigated condition and STI index were same as cluster analysis.

In order to study genetic diversity of different wheat inbred lines and grain yield modeling as well as selection of elite lines, 305 wheat lines derived from Roshan × Falat cultivar along with their parents as well as two check (Mahdavi and Shahpasand) cultivated in research field of Sahid Bahonar university of Kerman in augment design, on growing season of 2013-2014. Result of genetic and phenotype correlation has high coincidences together that shown infer low influence of environment error to relationship between evaluated traits. According to results of correlation analysis significant correlation was seen between grain yield and most of evaluated traits. Results of ANOVA of evaluated traits showed non-significant difference between check varieties in different incomplete blocks, this showed the homogeneity of experiment field. Stepwise regression model showed%81 changes of grain yield is justified by 1000 grain weight, number of grain per single plant, number of fertile tiller, plant hight and awn length. By factor analysis for the 13 evaluated traits shown%65 of variation in grain yield is justified by four factors, cluster analysis categorized the lines into three groups, the dendrogram revealed lines the third group of lines white the second group have significant difference. Evaluation of grain yield potential and phenotypic diversity measured traits lead to selection 40 better inbreed lines in this research. Results of this research showed number of grain per single plant, number of fertile tiller, grain filling period and awn length would be recommended traits for indirect selection for improvement grain yield.

In the major wheat growing countries, wheat growth and yield are negatively affected by salinity and breed tolerant cultivars through selection and breeding techniques is necessary to solve this problem. Relationship among yield, and its related traits in 23 wheat cultivars and promised lines were studied under salt stress conditions using a randomized complete block design with three replications at research field of Birjand University. Bread wheat cultivars and promised lines cultivated at two cropping seasons of 2010 and 2011 and irrigated with 10.81 ds.m-1 irrigation water during each season. Investigated cultivars and lines were significantly different in almost all traits except for days to heading and peduncle length. Correlation analysis showed that grain yield was significantly related to all traits except for number of spike per square meter and grain weight per spike. Regression analysis using step-wise method revealed that 81 percent of total variation exists in grain yield have been determined by grain filling period, plant height, and spike and peduncle length, in which grain filling period alone determined 54% of the variations. According to path analysis, grain filling period had the highest direct effect and peduncle length had the highest indirect effect via plant height on grain yield. These four traits are suggesting as suitable traits for selection of high-yield wheat lines under salt stress conditions.

In this study, genetic diversity was evaluated for 40 landraces and improved rice genotypes by inter-simple sequence repeat (ISSR), IRAP (Inter-Retrotransposon Amplified) and REM (Retro transposon-Microsatellite AmplifiedPolymorphism) marker systems. Amplified productions of 20 primers indicated distinct and polymorphic bands among genotypes that produced a total of 309 bands and an average of 88.03% polymorphism. The average gene diversity, Shannon’s diversity index and polymorphism information content were 0.39, 0.57 and 0.35, respectively. UBC811 and UBC813 markers showed the highest genetic diversity indices which were 0.65 and 0.64, respectively. In order to determine the efficiency of the markers in polymorphism appearance, marker index (MI) and effective multiplex ratio (EMR) were calculated which based onTOS2倐볗嚧 TOS2倐볛 markers with the highest MI and EMR value, had better efficiency, respectively. The dendrogram obtained using UPGMA method divided genotypes into six clusters. The most of local rice varieties including Hashemi, Alikazemi and Hassansaraiee located in cluster two whereas improved cultivars such as Khazar, Kadous and Gohar located in cluster three. Also, the results indicated that markers based on retrotransposon as REMAP have good potential for using in genetics and breeding researches in rice.

In order to study the relationship between grain yield and some of agronomic traits under drought stress condition, an experiment with 305 bread wheat inbred lines derived from a cross between Roshan × Falat and 25 drought tolerant and susceptible varieties along with 4 check varieties (Roshan, Falat, Mahdavi and Shahpasand) was conducted in augmented complete block design, at Research Field of Shahid Bahonar university of Kerman during 2013-2014 growing season. Normal irrigation was applied until flowering stage. Irrigation-cut off was done at 50% of flowering stage. Different traits such as grain yield and some agronomic traits were measured. Grain yield showed significant correlation with all the yield components including number of spike per plant, number of grain per spike, number of grain per plant and 1000- seed weight. Based on stepwise multiple linear regression, four traits including number of grain per plant, plant weight, 1000- seed weight, and flag leaf pod length were entered to the model, and totally explained 80.52% of grain yield variation. Number of grain per plant was the first trait which entered to the model and explained 72% of grain yield variation. Based on path coefficient analysis number of grain per plant had the most direct effect on grain yield (0.75) while it showed the highest indirect effect through number of spike on grain yield (0.66). Based on the multiple linear regression and path analysis, it is concluded that number of grain per plant had the most important effect on grain yield variation. Therefore, it is effective trait for improving grain yield under drought stress conditions.

Assessment of genetic diversity is important step for exploitation from plant material in breeding programs. In this study, genetic diversity of 55 barley lines evaluated using SSR markers and also microsatellite markers were used to identify informative markers associated with phonological and yield traits related to drought escape including days to heading, grain filling period, days to physiological maturity, thousand kernel weight and grain yield. These traits were evaluated in rainfed conditions. In order to, DNA was extracted from young barley leaves and the PCR products by using 35 pair SSR primers were loaded on 4.5% denatured polyacrylamide gel that 25 pair primers produced clear and polymorphic banding pattern. In general, 186 polymorphic bands detected. The number of observed polymorphic bands varied from 2 to 14, with an average of 7.44 bands per pair primers. Polymorphic information content (PIC) for primers ranged from 0.18 to 0.45, with an average of 0.32. Studied barley lines divided to 3 groups by cluster analysis. Lines were relatively favorable separated according to geographical origin which presents the efficiency of microsatellite markers for the detection of genetic differences and similarity. Also, 24 Informative markers identified in association analysis. Detection of informative markers can be used in mapping of quantitative trait loci for phonological and yield traits related to drought escape and can facilitate the identification of drought-escaping barley genotypes and leads to saving time, expense and labor.

Leaf Rust or rust fungus Pucciniatriticinacauses leaf, Is one of the most destructive fungal disease of wheat worldwide. In this study, in order to resistance evaluate to brown rust on 41cultivars of wheat was in field and greenhouse situation and based on randomized complete block design with three replication. Traits including infection type, disease severity, Area under Disease Progress Curve and latent period were recorded. Analysis of variance showed significant differences between genotypes for all traits. Correlation analysis showed a high and positive correlation between the traits in the field and showed high and negative correlation between the traits in greenhouse situation. Cluster analysis based on Euclidean distance and complete linkage algorithm was used to clustering of genotypes. In the cluster analysis cultivars were divided in to 2 groups in field and 3 groups in greenhouse.

In this research, the possibility of applying selection index of ideal genotype (SIIG) technique for identify tolerate genotypes using the different drought tolerance indices be amended. The experiment was conducted as split plot based on randomized complete block design with three replications at the experimental farm of agricultural research institute and natural resources, Yazd, Iran in 2011-2012. Three irrigation levels consisting of irrigation after 80mm evaporation from class “A” pan as control, no irrigation from stem elongation stage until flowering and flowering stage until podding stage were applied in main plots and Subplots were six winter canola cultivars. Thirteen drought tolerance indices including stress susceptibility index, stress tolerance index, tolerance index, abiotic-stress tolerance index, stress susceptibility percentage index, stress non-stress production index, relative drought index, harmonic mean, percentage of yield reduction, yield stability index, yield index, mean productivity and geometric mean productivity and also selection index of ideal genotype were calculated. The results indicated that drought stress significantly decreased the stomatal conductivity at stem elongation and flowering stages. Tassilo genotype with the highest selection index of ideal genotype values, near to one was accepted drought tolerance genotype; also Cooper and Adriana genotypes with the lowest selection index of ideal genotype values, near to zero were accepted drought susceptible genotypes at drought stress conditions from stem elongation stage until flowering. Lilian genotype with the highest selection index of ideal genotype value, near to one, perceived as the drought tolerance genotype under drought stress in flowering stage and Cooper and Adriana genotypes with the lowest selection index of ideal genotype values, near to zero were perceived as the drought susceptible genotypes. Thus, Tassilo and Lilian genotypes may be used as the genetic sources for drought resistance.

In order to obtain pure lines of corn for direct sowing or their usage in crossing, it is necessary to provide pure genotypes. This experiment was carried out by the use of individual selection breeding method and the 198 S6 lines of maize were evaluated in 2007and 14 traits were measured on them. The results of descriptive statistics showed considerable variation among genotypes. The maximum amount of phenotypic variation among different traits related to lodging resistance, disease resistance and grain yield traits with a value of 41.61, 21.3 and 20.88 percent, respectively. Cluster analysis by Ward’s minimum variance, clustered lines into three groups and the Percentage of grouping accuracy was 94.4 with discrimination function analysis. The first group consists of 23 lines, the second group included 110 line and the third group involved 65 line. The traits mean of lines at the first and second cluster were higher than traits mean of total lines and selected the lines of these two groups and were taken to the next generation that combining ability are evaluated through line × tester analysis. Also the lines of these two groups due to high value of yield and other traits can be used in hybridization programs. Also, factor analysis based on principal components after varimax rotation showed that 65.87 percent of total variations between genotypes were determined by five independent factors. According to the first two factors, the lines were divided into five groups. The result of factor analysis and cluster analysis to classify lines partially matched and confirmed each other.

In order to determine the stability and reaction of barley genotypes in different climatic conditions, grain yield of ten barley cultivars were evaluated in five locations. Studied areas were Karaj, Birjand, Kashmar, Sanandaj and Shiraz. The experiment conducted in a randomized complete block designs with three replications in 2013-2014. Genotype by environment interaction effect was significant for grain yield. To investigate the stability of the cultivars, stability parameters including environmental variance, Shukla stability variance, Wricke ecovalence, Lin and Bains coefficient variation and the variation coefficient stability parameter were assessed. According to these methods, Nosrat, Makuei and Gorgan cultivars with optimum performance were more stable than other genotypes. GGE - biplot graph in grain yield explained 91.54 percent of variations. According to GGE – biplot method Strain, Gorgan, Kavir and Nosrat had the high mean values of grain yield and stability. In contrast, Rayhan and Zarjou had the low mean values of grain yield and stability. For grain yield, studied locations divided to two mega-environments. The first mega-environment was Karaj and Birjand and the second mega-environment was Shiraz, Sanandaj and Kashmar. The second mega-environment regarded as the best mega-environment because of more number of varieties in with high grain yield. Karaj, Sanandaj and Shiraz had the most discrimination power in genotype recognition.

In order to study genetic diversity in rice genotypes In Iran, the variation in 38 rice cultivars were evaluated using 14 SSR markers. The experimental design was a randomized complete block at the research station located in the city in 1392 was Azadshahr. Plant samples at tillering genotypes were collected in the early morning. DNA was extracted from plant samples denaturation was carried out on polyacrylamide gels. Large genetic distances between cultivars showed high genetic diversity among the genotypes of rice. Principal component analysis of variance was 62%. The highest polymorphic information content RM262 (81/0) and lowest at RM241 (33/0) were recorded and the average PIC, 51/0 respectively. 33/0 Shannon's index of microsatellite markers used in this study, markers RM142 RM255, RM341, RM262, had high discriminatory power. The highest number of positive markers in height (11), respectively. Genotypes and cluster analysis methods into three classes, respectively. In general we can say the numbers in the high country of diversity and diversity in them can be used in breeding programs. Markers used in this study due to the high variability in their suffering, would be useful in future studies or remedial work.

Sorghum is the fifth degree of importance in the production of cereal after wheat, rice, maize and barley. Genetic diversity estimation of plant material is primary step for identification, protection and conservation of germplasm and breeding programs designing. In order to study of genetic diversity among 10 genotypes of grain sorghum, 10 microsatellite primers were used according to previous studies. Results of the experiment showed that the average polymorphic information content for all primers was 0.48, and the average observed heterozygosity for all Primers was calculated 0.29. The most Shannon index that reflects genetic diversity among populations, obtained in XTxp-312 primer. Also loci XTxp-287 and XTxp-354 had the lowest Shannon index (0.37). XTxp-312 primer had the highest amounts for Shannon index, expected and observed heterozygosity and the largest number of effective alleles. Thus this primer showed more genetic diversity than other primers. In other words, the genotypes showed higher diversity in the case of XTxp-312 primer. Cluster analysis based on molecular data using Jaccard's similarity coefficient and UPGMA method, classified the genotypes of sorghum into four major groups. Based on Principal component analysis results, the first two components PCA1 and PCA2 explained, 50.08 and 10.08 (total 60.15%) of the total variance respectively, indicating that SSR markers distribution across the genome have been relatively good. The overall results of this study showed genetic variation among sorghum genotypes based on microsatellite markers can be used in breeding programs.

Satureja bachtiarica L, an important medicinal plant from Lamiaceae family is valuable because of its medical compounds. Optimization of in vitro culture through callogenesis is proposed to be an alternative for vegetative propagation. In present study, an efficient protocol has been developed for callus induction of S. bachtiarica using different explants and concentrations of plant growth regulators on MS basal medium. Results indicated that the highest rate of callogenesis (16.82±0.94 days after culture) and callus volume (14.17±0.47) were achieved from internodes explants. On the other hand, for percentage of callus induction, shoot tips, internodes and nodal segments explants were more efficient than that of leaves explants. According to the results, the nodal segments cultured on medium supplemented with 1 mgl-1 BAP plus 1 mgl-1 NAA led to a remarkable decrease in induction rate of calli. Maximum callus volume was obtained from internodes explants cultured on medium supplemented with 0.5 mgl-1 BAP plus 0.5 mgl-1 NAA.

Salvia L. genus has antibacterial, antioxidant, antidiabetic and culinary properties. This genus consists of 55 species including 17 endemic ones in Iran. Out crossing and widespread distribution of Salvia L. genus plants have led to great impact on their morphological variation of ecotypes. This study was conducted for investigating morphological variation as well as characters relationships in nine ecotypes of four species named Salvia. nemorosa, S. spinosa, S. verticillata and S. virgata based on Randomized Complete Block Design with three replications in Agricultural Education Center of Qazvin. Difference among ecotypes was significant at all studied traits. All traits had positive and significant correlation with wet and dry weight of plants. On the other hand the correlation between leaf number and leaf length, leaf width and also the correlation of flower length and leaf and flower number were negative. The results of stepwise regression revealed that flowers and leaves dry weight and then branch number had more effects on total dry weight, respectively. In factor analysis, four primary factors justified 94.9 percent of total variation among characters and the first one named yield factor because of its high coefficients in weighting and numeral traits. Totally the results of this study indicated that genetic differences explained notable variation of characters than environmental effects.

The project disease index tolerance and yield components of 60wheat genotypes advanced and promising of hot and humid climate were evaluated in two years (2011-2012) to Fusarium head blight of wheat in the field conditions. Wheat infected spikes were collected in regional fields, separation, purification and identification performed in the laboratory. Genotypes were culture in the field in statistics design and were inoculated with a mixture of two races of causal fungi disease (Fusariumgraminearum, F.culmorum). In doughy stage, record dons of response of genotypes to disease-causing. At harvested stage, the entire plot harvested and measured performance indicators. Statistical analysis of the data was performed using statistical software. The results showed that the genotypes of sensitivity, tolerance and yield components have many differences. In cluster analysis of disease index and yield components data and drawing dendrogram, genotypes were divided into three to four groups with different genetic that the most genotypes were susceptible and moderately susceptible group. Study of the disease index and sensitivity index of genotypes, those in pedigree parental was such as Shanghai, Wang- shubai, Kauz, Milan and Babax were good in all ways.

Understanding the structure and nature of genotype environment interaction (GEI) is important in plant breeding programs. In order to study GEI effects on the seed yield and identify stable genotypes, 12 winter rapeseed (Brassica napus L.) promising lines along with Okapi cultivar (control) were evaluated in six cold (Bojnurd, Hamedan and Arak) and temperate regions (Karaj, Kermanshah and Isfahan) in 2010-2011 and 2011-2012 cropping seasons by using a randomized complete block design with three replications. Combined analysis of variance performed by assuming years and locations as random and genotypes as fixed factors. The results of combined analysis of variance showed that the year × location × genotype was significant at 5% level of probability. The GEI was examined using multivariate analysis technique as principal coordinate analysis (PCOA). According to grand means of test environments and total mean yield, test environments are grouped to low (three environments) and high (five environments) mean yield. Considering plot of minimum spanning tree and values of centroid distances, line G5 (L63) and Okapi cultivar were identified for unfavorable or poor environmental conditions. Also lines G3 (L201) and G8 (L119) were identified for favorable environments.

Increasing grain yield is the most important goal in any breeding program. Since yield is a complex trait and involves several quantitative components with low inheritance, its direct evaluation is not usually sufficient and therefore it is suggested that its components be investigated instead. The objective of this study was grouping 60 inbred lines along with four check cultivars of wheat from the different phonological and agronomic traits, and selection of superior groups. Therefore, these lines and cultivars were examined in (8 × 8) square lattice design with two replications. In analysis of variance for the evaluated phonological and agronomic traits, significant differences were observed in the most traits that indicate high genetic diversity of these traits. Cluster analysis showed that selection of first cluster of lines for phonological traits and second cluster of lines for agronomic traits with selection for early flowering and high plant height, awn length and biomass could lead to selection of genotypes with high number of spike per plant, seed number per spike, 1000- grain weight and grain yield. As well as, because of more easily evaluation and more heritability, these traits can be recommended for indirect selection of grain yield and its components of wheat under rainfed conditions.

Identification and classification of genetic source are important in plant breeding and genetic diversity. In order to evaluate genetic diversity of 48 Facultative wheat genotypes belong to north of IRAN, an experiment was done using 10 ISSR primers in the genetic laboratory of Gonbad Kavous University. Out of 62 produced fragments, 41 fragments were polymorphic. The number of polymorphic bands were different from 2 to 8 for each primer. The maximum number of polymorphic bands were related to PRI – 10. PIC value were variable between 0.375 to 0.498 and Marker index were variable between 18.75 to 39.84. The maximum percent of polymorphism with 80% were belong to PRI-4 and PRI–10, and the minimum percent of polymorphism with %50 were belong to (PRI -2 PRI -4), (PRI -3 PRI -4) and PRI-5. (PRI-3 PRI-4) and PRI-5 showed maximum Shanon index with 0.666 and 0.502, respectively. The maximum and minimum Nei genetic variability were observed for (PRI-3 PRI-4), and PRI-5 as 0.336 and 0.474 respectively. Maximum (1.908) and minimum (1.584) number of effective alleles obtained for (PRI-3 㴒4), and PRI-5, respectively. The 48 genotypes were grouped in four groups by using Jacard Coefficient similarity in UPGMA cluster analysis. Cluster analysis showed that ISSR markers are reliable to manifest higher level polymorphism. It also showed that ISSR indicators is useful to evaluate genetic variability and breeding programs in wheat.

Study of heritability, types of genes action and determination of effective breeding strategy to improve physiological and morphological traits especially under drought stress conditions are very important. For such purpose, an experiment was carried out using the generations of the crosses between two pure lines (Kavir × Roshan) under drought stress and non-stress conditions based on randomized complete block design with three replications in 2012-2013 in the research station of University of Tehran, college of Abouraihan. Analysis of variance of traits showed the significant differences among generations for most of traits in two environmental conditions. In present study, estimate the effects of genes with control important traits in P1, P2, F2 and F3 generations showed that under drought stress conditions the traits such as main spike length, main spike weight and under non-stress conditions the traits like main spike length and yield, thousand grain weight, three parameters model consist of [m], [a] and [d] was the best fitted model. Other traits such as plant height in non-stress conditions and main spike length and thousand grain weight in both conditions were controlled via over dominance effects of genes and peduncle length was controlled via complete dominance effects of genes. Under stress conditions the broad sense heritability was 19 to 83% for number of grain per plant and flag leaf length, respectively. However, under non-stress conditions the broad sense heritability was between 53% for number of fertile tiller to 93% for main spike length.

In this study, 12 retro transposons-based primers (7 IRAP and 5 REMAP primers) and general and mixed linear models (GLM and MLM) were used to identify molecular markers associated to 22 agro morphological traits in 48 different confectionery sunflower accessions. Studied accessions were divided into three main groups using Neighbor Joining method. Study of population structure as a prerequisite for association analysis showed that there is two possible subgroups (K=2) in the studied population. Based on GLM and MLM, 131 and 117 loci showed significant (P

TThis study was undertaken with the objective to determine the association between grain yield and its components and identifying traits have the greatest effects on grain yield of 45 mutant lines from tarom-mahaliin a randomized complete block design with three replications. Analysis of variance showed significant differences among genotypes for all traits. Mean comparison showed that line 2 (M6 – L 435) was supperior than other genotypes as regards to its yield, filled grains per panicle, panicle number and panicle length. Correlation coefficients between traits indicate that traits the number of filled grains perpanicle (0.855), panicle length (0.929) and panicle number (0.904) were positive and significantly associated with grain yield. Results of stepwise regression showed that the traits including panicle length, number of filled grains perpanicle, panicle number and plant height explained 92.5 percent of grain yield variation, respectively. Results of path analysis showed that maximum direct effects belonged to the panicle length (0.514), number of filled grains perpanicle (0.299) and panicle number (0.153).Panicle number had the greatest indirect effect (0.470) on grain yield through panicle length. On the basis of results of this study, panicle length, number of filled grains perpanicle, panicle number and plant height identified as selection criteria for grain yield improvement in rice.

In order to assess tolerance to drought and resistant and susceptible genotypes, 86 genotypes of native and commercial wheats were evaluated in germination stage with a factorial experiment in a completely randomized design with three replications. Two levels of osmotic potential of zero (control) and -4 bar. PEG 6000 were used to create the tension of the material. Different morphological traits were studied 8 days after planting the seeds on the seedlings. All the studied traits had significant differences in the level of one percent except the number of roots between the two levels of osmotic potential. In other words, the number of roots in different genotypes, were not affected by the drought stress. The effects of genotype and genotype × environment for all examined characteristics were significant at the one percent level. Stress decreased all germination index but this decline was not equally in all the traits, such as decline in the shoot was more noticeable than the root length. Stepwise regression analysis based on regression model with six variables were fitted to control circumstances and bivariate regression models were fitted to experimental data for stress. The genotypes were classified based on all traits using cluster analysis in the stage of germination in both environments. Genotypes in each environment (stress and control) were clustred separately that resistant and sensitive genotypes. Biplot analysis based on two main components were used on tolerance and susceptibility indices that resistant and susceptible genotypes were classified in two differenti groups based on the dry weight of biomass in both the stress and control condtion. According to the result of this research, the genotypes including Khazar 1, Khoi, Chamran and mahdavai have been identified as sensitive and also the genotypes of Bolani, Simineh and Golestan were drought tolerance.

In order to study the relationship between morphological and agronomic characteristics like grain yield in barley, and to obtain better knowledge of the effective attributes on barley, an experiment was conducted at the Agricultural Research Station of Ghachsaran in randomized complete block design with two replications on 18 barley lines. Results showed that some characteristics such as days to maturity, days to heading, number of seed per spike, spike length and early growth power of plant had high correlation with grain yield. Maximum variation in grain yield could be attributed to the days to maturity, agronomic score, early growth power of plant, number of seed per spike, spike length and days to heading respectively. The results of path analysis also revealed the importance of the direct effect of the days to maturity which was mainly due to indirect effect of peduncle length.

Drought stress is an important limiting factor for plant growth. Using selection indices, it is possible to identify cultivars with high yield in normal and stressed conditions. So, the genetic analysis of drought tolerance indices can play important role in plant breeding programs. In order to identify molecular markers linked with drought tolerance indices in sunflower, 72 recombinant inbred lines produced from a cross between RHA266 and PAC2 lines, were evaluated in 8×9 rectangular lattice design with two replications in normal and water-stressed in field conditions. Based on bi-plot produced from the principal component analysis, high genetic variability was observed among studied lines. Among the studied indices, a significant positive correlation was seen between GMP, MP, HM, YJ and SVI indices with seed yield in both normal (Yp) and water-stressed (Ys) conditions. Using composite interval mapping, 32 QTLs were detected for studied drought tolerance indices. Results showed that the identified QTLs for YI, MP, GMP indices in linkage groups 13 were co-localized with QTLs reported for sunflower yield. Therefore, it is possible to use GMP, MP and YI as the most appropriate indices for selection of drought tolerant lines in sunflower.