外源NO对水分胁迫下苜蓿种子萌发的影响

Effects of Exogenous Nitric Oxide on Germination of Alfalfa Seeds under Water Stress

以苜蓿王和德宝2个苜蓿品种为材料,用聚乙二醇(PEG-6000)为渗透调节剂模拟水分胁迫,用一氧化氮(NO)供体硝普钠处理苜蓿种子,研究NO对水分胁迫下苜蓿种子萌发的生理效应。结果表明,水分胁迫显著抑制了2个苜蓿品种的发芽势、发芽率、胚根长和胚芽长及幼苗干重(P<0.05),且随着胁迫强度的增加,各萌发指标相应降低,外源NO能够提高水分胁迫下苜蓿种子的发芽势、发芽率、胚芽长及幼苗干重(P<0.05)。因此,水分胁迫抑制了苜蓿种子的萌发,而添加外源NO能够显著降低水分亏缺给苜蓿种子萌发带来的胁迫作用,活化种子萌发生理过程。

The seeds of two alfalfa varieties （Medicago sativa L. cv. Emperor and Medicago sativa L. cv. Debay） pretreated with NO - donor SNP were used to study the physiological effects of exogenous nitric oxide on germination of alfalfa seeds under water -stress. The results showed that germination potential, germination rate, radicle length, embryonic bud length and seeding dry weight of the 2 alfalfa varieties decreased with increasing water stress, while increased with applying exogenous NO. It could be concluded that exogenous NO mitigated inhibition of water stress on germination potential, germination rate, radicle length, embryonic bud length and seeding dry weight of alfalfa, and activated the physiological processes of the seeds germinating.