Ten wheat genotypes were tested in a randomized complete block design with three replications under two irrigated and rainfed conditions to identify drought tolerant genotypes. Indices of drought tolerance were calculated based on the potential (Y_p) and under stress (Y_s) yield. Analysis of variance of indices exhibited highly significant differences among the geometric mean productivity (GMP), mean productivity (MP) and stress tolerance index (STI) and non-significant differences between the stress susceptibility index (SSI) and stress tolerance (TOL) indices. This indicates the existence of genetic variation for the attributes studied and the possibility of selection for drought tolerance genotypes. The highest significant positive correlations were found among GMP, MP and STI indices and potential and under rainfed yield. The highest GMP, MP, and STI were related to the TV2 genotypes. Principal component analysis reduced five indices down to two components with 99.49% proportional cumulative variance. Correlation and principal component analysis indicated that the most suitable criteria for the identification of genotypes under irrigated and rainfed conditions were GMP, MP and STI indices. Three dimensional plots exhibited that TV2 was the best drought tolerance genotype. Results of biplot analysis also identified the same genotype as the highest yielding one in both conditions.

The present study was conducted to understand the genetic diversity of bread wheat's that grown in Iran, and to evaluate polymorphism information content (PIC) of some wheat SSR primers. Experiment was done in the genomics Laboratory in Islamic Azad University, Khorramabad branch, Iran in 2012. Ninety-two bread wheat varieties were assayed to study the genetic diversity and polymorphism based on forty whole-genome SSR markers. Eighty alleles were identified and 2 alleles per locus were detected. The majority of SSR markers showed a high level of polymorphism. PIC values ranged from 0.12 (XBARC 148) to 0.80 (XBARC 54), with an average of 0.59 per primer, which indicates that markers were highly informative. According to similarity matrix, genetic similarity value ranged from 0.17 to 0.88. The lowest and highest genetic similarity were observed between 'Mihan' and 'Star' (No 31 and 57), 'Azadi' and 'Mahdavi' (No 4 and 6), respectively. Cluster analysis using the UPGMA method based on Jaccard coefficients was performed. Based on cluster analysis, 92 wheat cultivars were grouped in six clusters. Results indicated that Iranian grown wheat cultivars had high genetic diversity which could be exploited in wheat breeding programs.

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The correlation and path coefficient analysis of some kernel quality traits have been studied for 92 cultivars, breeding lines and landrace varieties of bread wheat (Triticum aestivum L.). Ninety-two genotypes were evaluated in alpha lattice design with two replications. Result of analysis of variance indicated that there were significant differences among genotypes in the most of traits. The correlation analysis showed that there were significant positive correlations among thousand kernel weight (TKW), grain length (GL) and grain width (GW). We also showed TKW, GL and GW had positive correlation with grain protein percentage, gluten weight, and falling number. Grain protein was significantly correlated with several kernel characteristics including: TKW, GL, GW, hardness index, gluten weight, SDS sedimentation, and falling number. On the first and second steps of stepwise regression analysis, protein percentage and falling number were the most effective traits in explaining different trait variations. Path coefficient analysis also showed the direct and significant effects of grain protein percentage and medium direct effect of falling number on SDS sedimentation. This result can be used in wheat breeding programs.

Barley ranks below wheat, corn and rice in total world production. Barley is one of the most important crops in Iran. In this study, genetic diversity of 20 rainfed barley genotypes were assessed using morphological traits as well as 20 primers of ISJ semi-random markers. There were significant differences among genotypes for the all traits, indicating high genetic variation among barley germplasm. Based on molecular data, 133 bands were detected and 89 bands were polymorph. The mean number of bands was 6.65 per primer. According to cluster analysis of similarity matrix of molecular and Euclidean distances of morphological data, similarities ranged between 0.42-0.85 and 1.44-43.22, respectively. Based on molecular data and morphological traits, the highest similarities were belonged to genotypes number 2, 8 (0.85), and 5, 8 (1.44) respectively. The results showed that intron-exon splice junction (ISJ) markers and morphological traits rather could distinct two and six-rowed and also hulless and hulled barley genotypes. Distinction of two clusters did not follow the same pattern.