Effects of simulated acid rain on growth of wheat (Secale cereale L.) in north China

Most literatures used southern soil which is Laterite or Latosol (acidic red soil) to simulate acid rain in south China to study the effects of acid rain on special growth period of wheat. To investigate impacts of simulated acid rain (SAR) on crops in north China, wheat samples were sprayed in pot experiments during their vegetative and reproductive growth periods with a range of SAR solution at pH 2.0, 3.0, 4.0, 5.0 and deionized water (the control) by measurement of fresh & dry weights and leaf area of the plants, determination of chlorophyll (Chl), malondialdehyde (MDA), and catalase (CAT) in the plants organs, and observation of injury symptoms. The results indicated that the threshold value where blade injury was visible after the treatment with acid rain was at pH 3.0. Treatment with SAR had no significant effects on soil pH during the experimental period. After the treatment of SAR, MDA contents increased, but Chl contents decreased and activities of CAT were suppressed. Treatment with high acidity SAR reduced the wheat yields. Effects of SAR on wheat increased more dramatically with the increase of SAR acidity and were correlated with exposure times and doses of SAR.