Effects of cadmium on germination and molecular level in some cool climate cereals

In this study, it was aimed to investigate the effects of cadmium heavy metal stress applied at 3 different molarity (1 mM, 2 mM and 3 mM) on the germination physiology of the seeds of some cool climate cereals. To determine this, the effects of cadmium on the morphological characteristics and DNA of the germinating seeds of the plants were analyzed. In the study, bread wheat (Triticum aestivum L.), durum wheat [Triticum turgidum (L.) Tell. convar. durum (Desf.) Mackey], barley (Hordeum vulgare L.) varieties, and the wheat landraces [Triticum monococcum L. ssp. monococcum (Einkorn), Triticum turgidum L. ssp. dicoccon (Schrank) Thell. (Gernik) and Triticum spelta L. (Dinkel)] were analyzed three times each. The number of roots, root, and shoot lengths were used as morphological characteristics in germinable seeds. According to the results, the highest rates in terms of germination percentages in all molarity and varieties were observed in Golia, Kızıltan 91, Aida, and Dinkel varieties. According to the stress tolerance index (STI) values, Bayraktar, Çıfçıklı, Ovidio, Çeşit 1252, İnce 04, Aida and Gernik stand out as with high tolerance. According to the two-way ANOVA results of the variance observed in the morphometric data, it was shown that the effect of the doses applied in the study was very large, but although the effect of the varieties was lower than the doses, their effects were also greater. The atomic absorption spectroscopy (AAS) results displayed that the percentage of cadmium accumulation in plants was higher in the roots than in the shoots. The five Inter Simple Sequence Repeat (ISSR) primers used for molecular analyzes produced 92 polymorphic loci and 13179 bands. ISSR molecular markers determined the changes on the DNA in all experimental groups compared to the control group. The dendrogram constructed using the unweighted pair group method with arithmetic mean (UPGMA) based on the genetic distance calculated according to ISSR PCR data clearly displayed the phylogenetic relationships of wheat and barley used in the study. Since cadmium, as a heavy metal, can negatively affect the health of humans and other living things in the long term, even at low concentrations, necessary precautions should be taken to prevent it from entering the food chain. As a conclusion, it was concluded that as the molarity of cadmium increases, heavy metal stress increases and negatively affects the germination physiology of the seeds of plants, the growth and development of roots and shoots, and that the genotypes of varieties respond to heavy metal stress at different levels.