Abstract:Effects of Cadmium (Cd) stress on the physiological indexes, rhizosphere soil indexes, and the bioaccumulation ability in Helianthus tuberous L. of Weifang and Xuzhou were studied by a soil culture experiment. Experimental treatments included CK (Cd2+ 0 mmol/L as control), T1 (Cd2+ 0.1 mmol/L), T2 (Cd2+ 0.5 mmol/L) and T3 (Cd2+1.0 mmol/L). The results showed that all of the root lengths, plant heights, leaf lengths, and leaf widths of two varieties of Helianthus tuberosus were inhibited to some extent under different Cd stresses after 21 days. The activities of antioxidant enzymes were decreased with the increasing of Cd concentrations. While the changes of MDA contents were different in two varieties. The MDA contents of Weifang H. tuberous were increased with Cd stress, but those of Xuzhou H. tuberous were increase only under T3 reaching the highest MDA content after 21 days, which was 3.52 times of CK. The rhizosphere soil pH decreased approximately linearly, and both values in Weifang and Xuzhou H. tuberous decreased the most after 20-day treatment of T3, with 3.85% and 3.41% respectively lower than those of CK. The organic matter contents were increased with the increasing Cd concentrations, with the largest increase of 38.60% and 36.01%, respectively in Weifang and Xuzhou H. tuberous after 20 days. As Cd concentrations became higher, it inhibited the uptake of alkali-hydrolyzable nitrogen (AN) in soil by Helianthus tuberosus. The overall inhibition was greater than that of Xuzhou H. tuberous. The destinations of Cd transfer were different in two varieties. With the increase of concentrations, Cd almost equally transferred to the leaves and stems in Weifang H. tuberous, while most of Cd in Xuzhou H. tuberous transferred from the roots to the stems. The results indicated that H. tuberous has a strong ability to accumulate Cd and a certain resistance under Cd stress, even more obvious for Xuzhou H. tuberous. Therefore, H. tuberous could be applied in Cd-polluted soils with both economic and ecological significance.