硝酸镨对镉胁迫下水稻种子萌发的缓解效应

Alleviating Effects of Pr^(3+) on the Cadmium Stress in Rice Seeds Germination

以水稻为试验对象,研究不同浓度硝酸镨(Pr3+)对镉胁迫下水稻种子萌发的效应及其生理生化变化。结果表明,低浓度镨处理能够促进镉胁迫下水稻种子的萌发状况,增加幼苗根质量和芽质量,增强超氧化物歧化酶和过氧化物酶活性并且降低了膜脂过氧化产物MDA含量,从而缓解了镉的毒害效应,其中以40 mg/L镨处理效果最好。但随着镨浓度的增大,镨对镉胁迫的缓解效应逐渐减弱,当镨浓度达到200 mg/L时,加剧了镉对水稻幼苗的毒害,表现为协同效应。

An experiment with Neixiangyou No. 8518 rice seeds was carried out to study the effects of Pr on the seed germination and physiological and biochemical changes of the seedlings under cadmium stress. The results showed that low Pr concentration, specially for 40 mg/L Pr,was beneficial to alleviate the harmful effects of Cd stress on germination and seeding, which promoted seed germination, increased the weight of seedlings and the activities of SOD and G-POD, and re- duced the MDA content. However, the alleviated actions of Pr to Cd faded away with the advancement of Pr concentration. When the concentration of Pr came to 200 mg/L,the Pr cooperated with the Cd to aggravate the poisoning action of the rice seedling.