Abstract:

In order to study the effect of Cu stress on Lactuca sativa L. seedlings growth and four soil enzymes activities (urease, calatase, acid phosphatase and intertase), potential concentration ( 50, 300, 500, 800, 1200, 2000 mg/kg dried soil) effects of Cu stress on Lactuca sativa L. seedlings growth indexes and red soil enzymes activities were investigated under field-simulated condition. The results showed that contrasted with control (native soil); increasing of Cu concentration resulted in higher leaves injury rate. With the increasing of Cu concentration, vitality, fresh weight, plant height and average root length of Lactuca sativa L. seedlings decreased. Soil enzymes activities decreased with increasing degree of soil pollution by heavy metal Cu，especially acid phosphatase and urease activities were decreased significantly with increasing contamination. Correlative analysis indicated that both urease, calatase, acid phosphatase, intertase activities and fresh weight, plant height and average root length of Lactuca sativa L. had significantly or very significantly negative correlation with Cu stress. Four enzymes activities had significantly or very significantly positive correlation with Lactuca sativa L. seedlings’ physiological indexes. The activity of the four species of soil enzymes was closely related to concnetration of Cu, and hence could be used as indicator of the degree of Cu pollution in soil.