Influence of Lherzolite on the Growth of Chinese Spinach and Soil Respiration in Cadmium Contaminated Soil

A glasshouse pot experiment was conducted to investigate cadmium (Cd) tolerance on the growth of Chinese spinach (Spinacia Oleracea L.) grown in sandy loam soil and microbial respiration after application of lherzolite (0%, 2.5% and 5%) with added Cd (0, 2.5 and 5 mg·kg-1). Soil pH tended to increase with increasing application rate of lherzolite about 1.5 units after plant harvest. Plant growth and microbial respiration in one hand decreased with the rates of Cd application in soil but on the other hand lherzolite application in soil reduced Cd toxicity and enhanced plant growth and microbial respiration. Microbial respiration of soil showed significant positive relationship with shoot and root dry weight of spinach but negative relationship of Cd concentration in plant tissue. This result indicated that application of lherzolite detoxified Cd toxicity in plant resulted in an increase plant growth and microbial respiration in Cd contaminated soil.