低温胁迫对紫花苜蓿种子萌发的影响

Effects of chilling stress on seed germination of alfalfa

以肇东苜蓿和WL440分别作为耐寒品种和不耐寒品种,通过10℃低温胁迫处理,以25℃为对照,记录两个苜蓿品种的发芽状况,并测定7日龄幼苗的生理生化指标,结果表明:低温胁迫下,苜蓿种子发芽率显著降低,发芽时间延长,幼苗生长缓慢,植株较弱,长期低温将导致幼苗死亡;低温胁迫还会使细胞受损,发生膜质过氧化反应、积累活性氧,而具有清除活性氧功能的保护酶系统却被低温抑制,使活性氧的产生与清除失衡,造成氧化损伤,导致细胞损伤甚至死亡。

Two alfalfa varieties,Zhaodong and WL440,were taken as cold-tolerant and non-cold-tolerant varieties respectively.The germination status of the two alfalfa varieties was recorded through the chilling stress treatment of low temperature at 10℃and 25℃as the control,and the physiological and biochemical indexes of 7-day-old seedlings were measured.Results showed that the germination rate of alfalfa decreased significantly,the germination time was prolonged,and seedlings grew slowly under chilling stress.Chilling stress can also damage cells and cause membrane peroxidation and accumulation of reactive oxygen species.The protective enzyme system with the function of removing reactive oxygen species was also inhibited by low temperature,leading to the imbalance between the generation and clearance of reactive oxygen species,and also the oxidative damage.The cells were damaged or even dead.