Revealing the genetic diversity and population structure in Aegilops crassa and Aegilops cylindrica species using molecular markers and physio-chemical traits.

In this work, we evaluated genetic diversity and population structure in eighty-eight Aegilops accessions using several physio-chemical traits such as shoot fresh and dry biomasses (SFW and SDW), photosynthetic pigments and activity of several antioxidant enzymes such as catalase, guaiacol peroxidase, peroxidase, and ascorbate peroxidase (APX), as well as 24 simple sequence repeat markers (SSR) under two control and water deficit stress conditions. The results indicated that water deficit stress dramatically affected SFW, SDW and photosynthetic pigments, while activity of all antioxidant enzymes were increased by water deficit stress compared to the control conditions. Statistical analysis of the phenotypic data showed a significant level of variation among the 88 investigated accessions. The results of correlation analysis showed that under both conditions photosynthetic pigments had a significant correlation with each other. The correlation between SDW and the activity of APX was positive and significant. The results of AMOVA using 24 SSR markers revealed that the genetic diversity observed among populations is more than within populations. Multivariate analyses grouped all investigated accessions in the clear groups based on their genomic constitutions. Based on results, 17 and 16 markers showed significant association with the measured traits under control and water deficit stress conditions, respectively. Our findings showed eight MTAs showed sufficiently stable expression across both control and stress conditions. Furthermore, several markers, especially Xgwm-455 associated with multiple traits across both conditions. In conclusion, these results could contribute to completing knowledge of the genetics and breeding for key physio-chemical properties. [ABSTRACT FROM AUTHOR]