Cd^2＋对玉米种子活力的影响及Ca^2＋的拮抗作用

用不同浓度（c）的Cd2＋和Cd2＋＋Ca2＋处理玉米种子，以研究Cd2＋对玉米种子活力的毒害及Ca2＋对Cd2＋的拮抗作用，结果表明：在0～0．5mmol／L的c（Cd2＋）范围内，种子的发芽率、幼苗生长量随c（Cd2＋）的增大而降低，Cd2＋能降低玉米幼苗中超氧物歧化酶（SOD）和过氧化氢酶（CAT）的活性，并能增加膜脂过氧化产物丙二醛（MDA）的含量．用Cd2＋＋Ca2＋处理玉米种子时，Ca2＋能减少以至消除Ca2＋对种子活力和幼苗生长的毒害作用，其中c（Cd2＋）为10mmol／L的拮抗作用明显大于5mmol／L．

EFFECT OF Cd~(2 ) ON SEED VIGOR OF ZEA MAYS L. AND ANTAGONISM OF Ca~(2 ) TO Cd~(2 )

Seeds of Zea mays L. were treated with different concentrations of Cd2 and different combinations of Ca2 (5 or 10 mmol/L) and Cd2 (0, 0. 1, 0. 2. 0. 3, 0. 4 and 0. 5 mmol/L),and the toxic action of Cd2 on maize seed vigor and antagonism of Ca2 to Cd2 were studied. Within 0~0. 5 mmol/L Cd2 levels, germination percentage of seeds and growth rate of seedlings were decreased along with the increment of Cd2 concentration. In the meantime, Cd2 could reduce the activities of superoxide dismutase (SOD) and catalase (CAT), and could increase the MDA (malondialdehyde) content of the product of membrane lipids peroxidation. As maize seeds were treated with different combinations of Ca2 and Cd2 ,Ca2 could decrease or/and remove the toxic action of Cd2 on seed vigor and seedling growth, in which the antagonism of 10 mmol/L Ca2 was more obvious than that of 5 mmol/L Ca2 .