低温胁迫对决明属牧草苗期活性氧化谢及其自适性响应的研究

试验研究低温胁迫对决明属牧草“CPI86134”品系苗期活性氧代谢及其自适性响应结果表明,随低温胁迫强度的提高和低温胁迫时间的延长,植株体内活性氧净产生速率、过氧化氢和丙二醛含量、叶片电解质渗透率均增加;植株体内活性氧清除酶超氧化物歧化酶、过氧化物酶、抗坏血酸过氧化物酶活性在0~48h胁迫时间内以较快速率提高,48h后其提高速率趋缓。活性氧清除酶活性的提高是“CPI86134”品系对低温胁迫伤害的一种自适性反应,活性氧、过氧化氢大量积累最终导致“CPI86134”植株体膜脂过氧化和膜系统的损伤。

Active oxygen metabolism and accommodation of Chamaecrista spp. under chilling stress in seedling period

Active oxygen metabolism and accommodation of Chamaecrista spp.CPI86134 under chilling stress in seedling period were studied.The results show that net rate of O_2 generation,H_2O_2 and malondialdehyde(MDA) contents,and rate of leakage of electrolyte significantly increase with enhanced and longer chilling stress;the contents of scavenging enzymes(SOD,POD,AsA-POD) also fast increase in 48 hours under chilling stress, then slowly drop.So we can conclude that the enhancements of scavenging enzymes activity are the adaptive response to chilling stress,and the severe accumulations of O_2 and H_2O_2 result in the lipid peroxidation and the damage of lipid system.