Abstract: In order to explore the effects of La(Ⅲ) on the energy metabolism of rice seeds under acid rain stress,the experiment of simulating acid rain(pH2.5) to rice seeds in distilled water and La(Ⅲ) was conducted.The effect of simulated acid rain on respiration rate,activity of CAT,mitochondrial protein,ATP content and Energy Charge(EC) of rice seeds were studied.The results showed that all the treated groups had the same alter trend with acid rain treatment period extending.The respiration rate of rice seeds declined at first then increased,and reached the peak on the forth day,then declined again.The activity of CAT and mitochondrial protein content increased slowly at the beginning.ATP content and EC of rice seeds increased sharply to the peak on the fifth day and then declined.All the targets of the AR+La groups were higher than that of the AR groups.These results indicated that La(Ⅲ) could lighten the damage of acid rain on mitochondria,and enhance resistance of rice seed to acid rain.

Key words: Acid rain stress, Acid rain stress, Energy metabolism, La(Ⅲ), Rice seeds