Responses of Agricultural plants to Lithium pollution: Trends, Meta-Analysis, and Perspectives

Abstract

Lithium (Li) is gaining attention due to rapid rise of modern industries but their ultimate fingerprints on plants are not well established. Herein, we executed a meta-analysis of the existing recent literature investigating the impact of Li sources and levels on plant species under different growth conditions to understand the existing state of knowledge. Toxic effects of Li exposure in plants varies as a function of medium and interestingly, more negative responses are reported in hydroponic media as compared to soil and foliar application. Additionally, toxic effects of Li vary with Li source materials and LiCl more negatively affected plant development parameters such as plant germination (n=48) and root biomass (n=57) and recorded highly uptake in plants (n=78), while LiNO3 has more negative effects on shoot biomass. The Li at <50 mg L-1 concentrations significantly influenced the plant physiological indicators including plant germination and root biomass, while 50-500 mg L-1 Li concentration influence the biochemical parameters. The uptake potential of Li is dose dependent and their translocation/bioaccumulation remains unknown. Future work should include complete lifespan studies of the crop to elucidate the bioaccumulation of Li in edible tissues and to investigate possible trophic transfer of Li.Environmental significanceAccumulation of Li sources is increasing in ecosystem compartments, and this might be vulnerable to plants.

Impact of Low Lithium Concentrations on the Fatty Acids and Elemental Composition of Salvinia natans

“…Butterhead lettuce ( Lactuca sativa ) increased the fresh roots’ weight following exposure to low (2.5 mg/kg) Li concentrations in soils. Likewise, a stimulatory effect on the root systems elongation was observed [ 8 , 9 ]. Exposure to 20 mg/L Li decreased by 20% the lettuce biomass 50 mg/L Li led to a severe decrease in biomass (≈70%), while 100 mg/L Li completely blocked the plant growth [ 8 ].…”

“…Tobacco ( Nicotiana tabacum ) plants treated with 30–50 mM Li induced the formation of necrotic spots and leaf curling, as well as incompatible pathogen interactions [ 11 ]. A 30 m M Li exposure had no negative effect on cabbage ( Brassica carrinata ) seedling germinations [ 12 ] but affected its chlorophyll, lipid and phenolic composition [ 9 , 12 ]. Li react with unsaturated fatty acids and destroy the lipid bilayer [ 13 ].…”

Lithium Accumulation in Salvinia natans Free-Floating Aquatic Plant

“…Due to the physicochemical similarities between Li, Na, K, and Ca, these elements can be easily uptaken by the plant’s roots through the same transport systems [ 42 ]. Li bioavailability, phytotoxicity, and its interaction with other elements, as well as the uptake mechanism and the specific role in plant species development, are not fully elucidated [ 42 , 43 ]. Moreover, the understanding of the dose–response relationship and short- and long-term influence on plant physiology is not currently elucidated.…”