NO供体SNP对酸雨胁迫下龙眼种子萌发及生理特性的影响

Effects of NO donor SNP on seed germination and physiological characteristics of Dimocarpus longan under acid rain stress

研究了不同pH值(2.0、2.5、3.0、3.5、4.0、4.5、5.0、6.5)模拟酸雨对龙眼种子萌发、幼苗生长的影响,以及外源一氧化氮(NO)供体硝普钠(SNP)对pH3.5酸雨胁迫下龙眼种子萌发和生理特性的影响。结果表明,模拟酸雨pH值小于4.0时龙眼种子的萌发受到显著抑制,pH 5.0模拟酸雨对龙眼种子萌发影响最小。较低浓度(0.25 mmol/L)的硝普钠能明显提高酸雨(pH 3.5)胁迫下龙眼种子的发芽率和发芽势,明显缓解酸雨(pH 3.5)胁迫下龙眼幼苗中丙二醛(MDA)的积累,提高根系活性;过高浓度(1.00 mmol/L)的硝普钠会对龙眼幼苗产生胁迫作用,龙眼幼苗发芽率和发芽势下降,MDA含量上升,根系活性下降。

The effect of simulated acid rain with different pH values （2.0, 2.5, 3. 0, 3.5, 4. 0, 4.5, 5.0 and 6. 5 ） on seed germination and seedling growth in Dimocarpus longan, and the effect of exogenous nitric oxide donor sodium nitroprusside on seed germination and physiological characteristics of longan under acid rain stress at pH 3.5 were investiga- ted. The results showed that longan seed germination was significantly inhibited by simulated acid rain with pH values less than 4.0, and the effect of simulated acid rain with pH 5.0 on germination of longan seeds was little. Low concentration （0. 25 retool/L） of sodium nitroprusside could enhance germination rate and germination vigor of the longan seeds under acid rain stress at pH 3.5, decrease the accumulation of malondialdedyde, and increase root activity of longan seedling. However, excess sodium nitroprusside （1.00 mmol/L） had stress effect on longan seedling, resulting in decreased germina- tion rate and germination potential, declined root activity, and increased malondialdedyde contents.