Genetic Diversity and Population Structure of Primary Tritipyrum Lines in Comparison with Bread Wheat Varieties and Triticale Lines using SCoT Markers

Triticale and tritipyrum as a new artificial cereal were investigated as potential stress-resistant alternatives within the Triticeae tribe due to their notable adaptability to environmental stresses.The first purpose of this study was to determine the genetic variation of 14 genotypes on physiological traits in arid and semi-arid climate of Yazd province on primary trans chromosomal tritipyrum (PTCT) lines, promising triticale lines, and Iranian and Afghan bread wheat cultivars, and the second purpose was to investigate the genetic diversity and classification of genotypes using start codon targeted (SCoT) markers. The photosynthesis pigments, proline, and catalase enzyme activity of 14 genotypes were determined. Also, genomic DNA of 10 genotypes was extracted using a modified CTAB protocol. The 13 primers were set-up for PCR and the studied parameters were analyzed with Excel, GenAlEx6.5, POPGen32, and STRUCTURE software.Based on 14 amphidiploids, Triticale 4115 and PTCT line (Ka/b)(Cr/b)F2 had the greatest carotenoids and photosynthesis pigments values. Proline content was highest in PTCT lines (Ka/b)(Cr/b)F2, triticale line 4115, and La(4B/4D)/b. The PTCT lines La/b and Az/b showed the highest (0.34) and lowest (0.04) average catalase, respectively. The investigation of genetic diversity in physiological traits related to the arid and semi-arid climate conditions of Yazd province showed that there is a great diversity between the genotypes. SCoT markers were used to analyze genetic diversity in 10 genotypes (four PTCT lines, two Afghan, and two Iranian bread wheat varieties and also two promising triticale lines). Additionally, 13 SCoT markers revealed 174 bands, 163 of which were genetically polymorph. The mean of polymorphic bands was 12.69 per primer and ranged from 3 to 24. Polymorphic information content was 0.25–0.4. The marker index and resolving power were estimated from 2.42 to 8.18 and 0.8 to 11.6. SCoT11 and SCoT17 primers had the highest MI and Rp values, indicating greater resolution. Pairwise genetic similarity values among the 10 genotypes (0.16-0.714), with the PTCT line (Ma/b)(Cr/b)F3 and bread wheat cultivar Kavir most distant. The SCoT data grouped genotypes into four clusters. As well, principal coordinate analysis showed that the three core coordinates explained 49.05% of genetic diversity. The examination of molecular variance showed that 79% of genetic variation was within populations. The level of diversity in bread wheat was higher than that in promising triticale and PTCT lines. Moreover, these varieties had more variation than PTCT lines for physiological traits. La(4B/4D)/b and (Ka/b)(Cr/b)F2 along with triticale line 4115, demonstrated superior physiological adaptation in arid and semi-arid conditions. Although astonishingly SCoT04 had the highest polymorphic content index, but the SCoT11 and SCoT17 could induce genomic dispersion and differentiate genotypes more efficiently. Furthermore,results showed that combined molecular markers and physiological analysis could be a useful approach to describe genetic diversity.