Phytotoxicity of Copper and Zinc in Tomato Plants (Lycopersicon Esculentum. Mill): Impact on Growth and Mineral Nutrition

Some agricultural inputs mainly contain copper and zinc and may accumulate in soils and can cause toxicity for soil and crops. This work aims to study the impact of copper and zinc at concentrations between 0 and 2000 mg/kg of soil on growth and mineral nutrition of tomato plants grown in pots experiments in a greenhouse. No plant could grow at concentrations of 1000 and 2000 mg/kg of Cu and above 400 mg/kg of Zn. Monitoring plants height for 14 weeks showed that after the 9th week, both metals stimulated growth at concentrations between 300 and 400 mg/kg, but a Cu application upper than these levels caused a growth restriction. The two metals at 200 mg/kg, enhanced fresh biomass production of the aerial part. At 500 mg/kg, the effect of Cu application became negative. Moreover, we can also note that the Cu application is always an antagonist for K. In contrast, 200 mg/kg of Zn aimed to improve the K assimilation.