The study was aimed to assess the impact of toxic metals (Ni, Pb, Cu) on soil contamination in Ukraine caused by military actions, and to evaluate their phytotoxic effects on plants, with a focus on Sorghum bicolor nothosubsp. drummondii f. alba as a potential candidate for phytoremediation. Seeds of S. bicolor were germinated under controlled conditions with varying concentrations of Ni(NO3)2, Pb(NO3)2, and CuSO4. Growth parameters of shoots and roots were measured, and tolerance indices (TI) were calculated. Statistical analyses included ANOVA, Tukey’s post hoc test, Shapiro—Wilk test, and Levene’s test, with significance set at p < 0.05. Nickel at 5—10 mg/L inhibited root growth but had little effect on shoots. Lead at 400 mg/L completely suppressed root formation, while lower concentrations caused moderate inhibition. Copper strongly affected root development, reducing biomass by up to 87 % at 100 mg/L, while shoots showed relative tolerance. Overall, roots were more sensitive to metal toxicity than shoots. Sorghum bicolor demonstrated moderate tolerance to heavy metal stress, maintaining shoot growth under contamination while restricting metal translocation to aerial parts. This suggests its potential use in phytostabilization strategies for soils polluted by military activities. The findings highlight the urgent need for bioremediation approaches to restore agricultural productivity and mitigate ecological risks in war-affected regions of Ukraine.
Keywords: Sorghum bicolor nothosubsp. drummondii f. alba, toxic metals, phytoremediation, nickel, lead, copper, tolerance
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