Cd^(2+)与NaCl胁迫对紫花苜蓿种子萌发的影响

Effects of Cd^(2+) and NaCl Stress on Seed Germination of Alfalfa

通过室内光照培养箱种子萌发试验,研究了Cd2+和NaCl胁迫对紫花苜蓿(Medicago sativa L.cv.)种子萌发的影响。结果表明,在NaCl单一胁迫下,随浓度增加对紫花苜蓿种子萌发有明显的抑制作用,种子的发芽势和发芽率抑制作用增强,发芽指数和活力指数下降,丙二醛含量先增加后降低。在Cd2+单一胁迫下,低剂量Cd2+可促进种子的萌发,高剂量Cd2+对紫花苜蓿种子的萌发有抑制作用,且随浓度升高,Cd2+对种子细胞膜的作用强烈,种子的生理受到干扰,MDA值随Cd2+浓度的增加而增加。在NaCl和Cd2+联合胁迫下,发芽率、发芽势、芽长、根长等胁迫效应介于两种化学物质单独作用效应之间。

Seeds of Medicago sativa L.cv.were used as test material to study the effects of different Cd2+and Salt contents on seed germination.The results showed that under the single stress of NaCl,with the in‐creasing of the concentration,seed germination had been inhibitied obviously,seed germination force and germination percentage had been strongly inhibited,germination indexes and vigour indexes decreased.But MDA gradually increased then decreased ;Under Cd2+ stress,lower concentration of Cd2+ promoted seeds germination,but the higher concentration of Cd2+ inhibited seed germination,and with the concentration of Cd2+ increasing,the MDA decreased and cell membrane of seeds had been affected strongly by Cd2+.Under the stress of the combination of NaCl and Cd2+,the stress effects such as seeds germinate percentage,ger‐mination vigour,bud length and root length were between two chemicals conducts stress separatly.