Influence of Organic Amendments on Growth and Lead Uptake of Spinach (Spinacia oleracea L.) Grown in Lead-Contaminated Soil

Abstract

Article · July 2020 CITATIONS 0 READS 23 9 authors, including: Some of the authors of this publication are also working on these related projects: Comparative growth and yield performance of different rice genotypes under salt affected field conditions View project determenant of financial development View project Tayyaba Naz University of Agriculture Faisalabad Lead (Pb) is a very serious contaminant in soil because of its widespread application in agricultural, residential and industrial environments and it has ultimately harmful impacts on plant and human health. Organic amendments such as biochar (BC) and compost may reduce heavy metal toxicity in a plant. The main focus of the present research work was to evaluate the synergistic use of BC and compost to enhance the growth of spinach and to reduce the Pb uptake in spinach (Spinach oleracea L.) grown on Pb-contaminated soil. The results showed that Pb toxicity at its higher-level (1000 mg Pb kg-1 soil) reduced the growth, photosynthetic pigments and physiological attributes in 45-days-old spinach. However, this decrease was less pronounced in BC and compost amended soil. The BC and compost application enhanced shoot dry weight, total chlorophyll contents, membrane stability index and relative water contents at both applied rates 500 and 1000 mg kg-1 of Pb in soil. Under low Pb-stress (500 mg Pb kg-1), BC and compost application increased the shoot dry weight (33.5 and 39.7%), chlorophyll contents (21 and 22.1%), membrane stability index (18.8 and 17%) and relative water contents (44 and 34.6%). While at high Pb-stress (1000 mg kg-1) BC and compost increased the shoot dry biomass (17.8 and 33.3%), chlorophyll contents (31.3 and 32.5%), membrane stability (27.1 and 23.5%) and relative water contents (37 and 32.9%) respectively. Moreover, under low Pb stress the application of BC and compost reduced the Pb uptake in spinach by 78 and 56%. While under high Pb stress, BC and compost reduced the Pb uptake by 69 and 52% respectively. Therefore, it can be concluded that organic amendments can ameliorate Pb-toxic effects in spinach by changing the physiological attributes (total chlorophyll content, MSI and RWC) under Pb stress. Among the tested amendments, applied BC proved more effective for reducing Pb toxicity in spinach.