Morphological and physiological diversity in bread (Triticum aestivum L.), durum (Triticum turgidum L. var. durum), Einkorn (Triticum monococcum spp. monococcum), and emmer (Triticum dicoccum ssp. dicoccum Schrank.) wheats under lead stress

Wheat is critical to global food security. However, environmental stresses, such as heavy metals, may significantly impact its growth and development. This study evaluated the effect of lead exposure on the growth of seedlings and the accumulation of enzymatic and non-enzymatic antioxidants in various wheat landrace cultivars. The investigation demonstrated the impact of Pb on parametric traits: seed germination, seedling vigor, shoot and root elongation, coleoptile length, root length, shoot fresh and dry weight, and root fresh and dry weight decreased as Pb concentrations increased. On the other hand, low concentrations of lead (50 µM and 100 µM) significantly increased these values in the Einkorn, Emmer, and Ekiz species compared to the Durum wheat cultivar. The soluble protein content of Durum at 50 µM and 100 µM of Pb (NO3)2 was significantly higher than in the other wheat species. However, the Ekiz cultivar exhibited higher protein content than the other species at higher lead concentrations (250 µM and 500 µM). The Durum cultivar lacked certain components (K, Ca, P, Mg, and Fe) at the lead concentration of 500 µM. Consequently, the amounts of chlorophyll a, chlorophyll b, and proline were lower than in the other wheat landraces. Ancient wheat landrace cultivars: Einkorn and Emmer showed higher antioxidant activity (CAT and SOD), phenolic compounds, carotenoids, and lower H2O2 levels compared to modern wheat species Ekiz and Durum when exposed to high concentrations of lead. The wheat landraces Einkorn and Emmer exhibited more resistance to lead stress in terms of shoot and root toxicity than Ekiz and Durum. Future studies should focus on identifying specific phenolic compounds and the antioxidant enzyme mechanisms underlying lead tolerance in wheat landrace cultivars. doldurulacaktır