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Aegilops and Triticum spp. are two ideal gene pools for the breeding purposes of wheat. In this study, a set of Iranian accessions of Aegilops tauschii Coss. and Triticum aestivum L. species were evaluated in terms of some physiological and biochemical features under control and water-deficit stress conditions. Moreover, several simple sequence repeat (SSR) markers were employed to identify marker loci associated with the measured traits. The results indicated that water-deficit stress significantly affected all measured traits and the highest reductions due to water-deficit were recorded for shoot fresh and dry biomasses (SFB and SDB), stomatal conductance (Gs), leaf relative water content (RWC), and chlorophyll b content (Chl b). In molecular analysis, 25 SSR markers generated 50 fragments, out of which 49 fragments (98%) were polymorphic. Furthermore, the genetic variation observed within species is more than between species. The results of cluster and Bayesian model analysis classified all evaluated accessions into three main clusters. Under control and water-deficit stress conditions, 28 and 27 significant marker-trait associations (MTAs) were identified, respectively. Furthermore, 10 MTAs showed sufficiently stable expression across both growth conditions. Of these, the markers Xgwm-111, Xgwm-44, Xgwm-455, Xgwm-272, and Xgwm-292 were associated with multiple traits. Hence, these markers could serve as useful molecular tools for population characterization, gene tagging, and other molecular breeding studies. [ABSTRACT FROM AUTHOR]

Flax is cultured for fiber and oil production around the world. The demand for flax is increasing in industries each year. In order to screening and selection of 86 accessions from five subspecies along with 19 unknown accessions, the seeds of the accessions were cultured in a randomized complete block design with three replications. The experiment took two years in Karaj, Iran. ANOVA results showed that the accessions and their interaction with year had significant effects on the measured traits (P <.05 or 0.01). Our results showed a substantial level of diversity among the accessions with respect to the measured traits. Based on correlation analysis, there were positive and significant relationships between seed yield (SY) and number of basal branches (NBB), capsules per main branch (CMB), number of capsules and seeds per plant (CP and NSP). Multiple linear regression analysis indicated that the predicting model explained 99% of flax yield variation in which the CP, NSP, and TSW were effective traits in describing the variation. Cluster analysis categorized the 100 accessions into seven clusters. Our results suggested that accessions '19ʹ and '35ʹ from the first and the third clusters could be cultivated as promising genotypes for SY and fiber production, respectively. [ABSTRACT FROM AUTHOR]