Effects of sulfur on the antioxidant system and photosynthetic characteristics in different rice genotypes under Cadmium stress

Two rice cultivars,‘Wuyunjing24'and‘Eryou107',were used to study the effects of Sulfur(S)on the activities of antioxidant enzymes SOD,POD,CAT and photosynthetic characteristics of flag leaf during heading and filling periods in different rice genotypes under Cadmium(Cd)stress.The result showed that cadmium absorbed in rice mainly concentrated on the root under cadmium stress,the activities of SOD,POD,CAT and content of chlorophyll were decreased.At the same time,photosynthetic capacity has been weakened during heading and filling periods under Cd stress.The accumulation of Cd can be significantly reduced by sulfur in two rice cultivars,and the accumulation of cadmium varied in different parts of rice.The activities of SOD,POD,CAT increased to a certain degree by exogenous sulfur during heading and filling period.In addition,the study also found whether under Cd stress or not,it is a trend that photosynthetic capacity of flag leaf can be increased by sulfur,which may be related to organic matter and sulfate supplied by soil.