Effect of Vanadium on Testa, Seed Germination, and Subsequent Seedling Growth of Alfalfa (Medicago sativa L.)

Abstract

Seed germination is the critical initial phase in the life cycle of plant and it is affected by various exogenous factors, including heavy metals. Seed germination and subsequent seedling growth of alfalfa (Medicago sativa L.) incubated in glass Petri dish in presence of elevated concentrations of pentavalent vanadium V(V) solution (0, 0.1, 0.5, 2, 4, 10, 50 mg L −1 V, supplied as NaVO 3 •2H 2 O) were evaluated. Results showed that vanadium did not (P > 0.05) affect seed germination, final survival rate, and seedling height of alfalfa when exogenously treated dosages were ≤ 10 mg L −1 V, whereas the root vitality and root elongation were distinctly inhibited at ≥ 0.5 mg L −1 V treatments. A progressively deepened testa color at increasing vanadium concentrations during germination and an apparent modified structure of the seed coat at 50 mg L −1 V compared to control in alfalfa were noted. Alfalfa seeds showed rapid and almost synchronous radicle emergence, independently of the vanadium concentration in the medium. The accumulation of vanadium in testa is beneficial to alleviate its toxicity to the seed germination of alfalfa. Leaf proline content was dramatically increased at ≥ 0.5 mg L −1 V treatments compared with the control. Emerged seedlings displayed enough vigor and health to potentially colonize in the vanadium-contained matrix. Thus, alfalfa represents a good candidate for phytoremediation approach aimed at decontaminating environments when vanadium concentrations are within the determined thresholds.

Exogenous 3,3′-Diindolylmethane Improves Vanadium Stress Tolerance in Brassica napus Seedling Shoots by Modulating Antioxidant Enzyme Activities

“…In this study, we observed an increase in seed germination after DIM treatment. Vanadium treatment led to a decrease in germination percentage and this result was in agreement with the observations of Wu et al [ 48 ], in which Medicago sativa seed germination was decreased by vanadium treatment (50 mg·L −1 ). However, in our study, the DIM and vanadium combination treatment improved seed germination when compared to the vanadium-only-treated seeds.…”

“…We also observed an increase in SOD and APX activity in the vanadium-treated seedlings. A SOD activity increase was also observed by Altaf et al [ 61 ] in O. sativa treated with vanadium and an increase in APX activity was also observed in vanadium-treated M. sativa by Wu et al [ 48 ]. The SOD activity increase in this study is also in contradiction with our results from the previous study, in which vanadium stress inhibited SOD activity in more mature AV Garnet leaves [ 11 ].…”

Heavy metal accumulation by roadside vegetation and implications for pollution control

“…Heavy metal pollution affects seedling growth and germination of roadside vegetation [41][42][43]. The germination rate of seeds is decreases due to excessive Pb toxicity [44,45]. Remediation is mandatory to control heavy metal pollution for recovery and restoration of ecosystem [46,47].…”

Rview of phytoremediation of soil contaminated by vanadium

“…High levels of vanadium (usually, ˃ 2 mg kg −1 ), however, lead to dwarfing, chlorosis, necrosis, membrane damage, cell death, growth retardation, root deformation, and reduced biomass [16,21,22] . Higher concentrations of vanadium not only negatively affected seed germination and subsequent seedling growth but also influence the reproductive growth of plants [23,24] .…”