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Biodiversity information in available germplasm is very useful for the success of any breeding program. To establish genetic diversity among 44 genotypes of chickpea comprising cultigen, landraces, internationally developed improved lines and wild relatives, genetic distances were evaluated using 19 simple sequence repeat markers with 100 marker loci. Estimation of the number of alleles per locus (n a ), the effective allele number (n e ), and Wright fixation index F were 6.25, 3.67, and 0.44, respectively.Polymorphism information content values ranged from 0.84 (locus NCPGR6 and TA135) to 0.44 (locus NCPGR7) with an average of 0.68. Dice's coefficient similarity matrix for studied chickpea genotypes varied from 0.07 to 1.0 indicating a broader genetic base among genotypes studied. The highest similarity, 1.0, was observed between genotypes Sel 96TH11484 and Sel 96TH11485; while, the lowest, 0.07, was observed between genotypes Sel 95TH1716 and Azad. Based on the UPGMA clustering method, all genotypes were clustered in eight groups, which indicated the probable origin and region similarity of landraces and local Iran landraces over the other cultivars and wild species. It also represents a wide diversity among available germplasm. Analysis of molecular variance revealed that 41% of the total variance was due to differences among groups while 59% was due to differences within groups. The results of principal coordinate analysis approximately corresponded to those obtained through cluster analysis. Genetic variation detected in this study can be useful for selective breeding for specific traits and in enhancing the genetic base of breeding programs.

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Drought stress is one of the factors which influence sunflower (Helianthus annuus L.) production. Breeding for tolerance to drought stress has become a major focus. In the present investigation, combining ability, gene action and genetic analysis of several characteristics were studied in six pure lines of sunflower and their 15 hybrids. The materials were evaluated in two separate experiments using a randomized complete block design (RCBD) with three replications in two states (well-watered and water-stressed) under controlled conditions. Comparison of mean values exhibited that under water- stressed condition the average performance of sunflower genotypes were decreased for all studied traits. In well-watered condition the highest value for seed yield per plant (SY) was observed in the cross 'LR4?LR25', whereas in water-stressed condition the highest value for this trait was observed in the hybrid 'C104?LR25'. Combining ability analysis revealed that most of agronomical traits such as head diameter, number of achene per head, head weight and seed yield inherited differently in stressed and non-stressed conditions. In water-stressed conditions, the non-additive effects played a more important role for controlling the number of achene per head (NA), seed yield per plant (SY), head diameter (HD), and days from flowering to physiological maturity (DFM) than additive. Based on results yield improvement for water-stressed conditions requires selection under drought conditions. In well-watered condition, the cross 'LR4?C10' showed the best SCA value for seed yield per plant (SY). In water-stressed conditions, 'RHA266?C100' had the highest SCA for seed yield per plant (SY) and number of achene (NA) per head.