| Abstract: | - Development of alleviation strategies, which enhance plant growth under heavy metal stress, is important. Inorganic (zeolite) and organic (diethylene triamine penta‐acetic acid, DTPA) amendments affecting the alleviation of lead (Pb) stress in a calcareous soil were tested by investigating leaf nutrient uptake of tomato (Lycopersicon esculentum L.) plants.
- Experimental quantities of lead (Pb) at 0, 50, 100 and 150 mg·kg?1 soil, zeolite (clinoptilolite) at 0%, 0.5% and 1%, and DTPA at 0, 50 and 100 mg·kg?1 soil were tested in a factorial experiment with three plant replicates.
- According to the anova , Pb, zeolite, DTPA and their interactions significantly affected plant concentrations of nitrogen (N), potassium (K), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb). With increasing DTPA concentration at different levels of zeolite and Pb, plant concentrations of macro‐ and micronutrients significantly increased. Increasing soil Pb increased leaf Pb concentration and decreased the uptake of N, K, Fe, Zn, Cu and Mn. Although with increasing Pb concentration the uptake of macro‐ and micronutrients decreased in tomato, the use of zeolite and DTPA alleviated this stress by increasing nutrient uptake compared to the control. Interestingly, however, increased levels of zeolite and DTPA led to a decreased uptake of nutrients by plants (compared with control), indicating the absorption of such nutrients by the two amendments and their partial release for further plant use.
- Zeolite and DTPA may alleviate the negative effects of soil Pb on tomato growth by decreasing nutrient leaching and increasing plant nutrient uptake.
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