模拟酸雨和铝添加对茶树生长及生理生化特性的影响

摘要

The growth and resistant physiological characteristic effects of simulated acid rain and aluminum (Al) addition on tea plants (Camellia sinensis) were studied in a hydroponic experiment with three pH rnlevels of 3.0, 4.0 and 5.0 and four aluminum degrees of 0, 10, 20 and 30 mg/L. The results showed that suitable Al and moderate acidity of acid rain were beneficial to the increase of biomass of tea plants, while higher Al and higher acidity of acid rain were harmful to the growth of tea plants. Superoxide dismutase ( SOD) , peroxidase ( POD) , calalase (CAT) and ascorbate peroxidase (APX) in tea leaves increased firstly and decreased later with increasing Al concentration and increased with increasing acidity of acid rain. At lower Al contentration, the increase of SOD, POD, CAT and APX caused by Al were intensified by acid rain. At higher Al concentration, the decrease of them were intensified by acid rain. The superoxide anion radical ( O2 -') generation rate and malonaldehyde ( MDA) content in tea leaves treated with 10 mg/L Al showed no difference compared with that without Al treatment, and than increased with increasing Al concentration. O2-' generation rate and MDA content in tea leaves were not affected by acid rain and the increase of them caused by Al was intensified by acid rain al higher Al concentration. Proline content in tea leaves increased with increasing Al concentration and was not affected by acid rain. The accumulation of proline in tea leaves caused by Al was intensified by acid rain. The soluble sugar in tea leaves increased firstly and decreased later with increasing Al concentration. Acid rain at pH 3. 0 significantly increased soluble sugar content in tea leaves. These results suggested that tea plant can adapt to acid rain and lower Al contentration by strengthening antioxidase activities and increasing osmoregulation substance, however, higher Al concentration is harmful to growth of tea plant for damaging antioxidation system and decreasing osmoregulation substance synthesis and the harm to tea plant caused by higher Al are aggravated by acid rain.%以茶树(Camellia sinensis)种子实生苗为材料,研究了模拟酸雨和铝添加对茶树生物量、抗氧化酶及一些抗性指标的影响.结果表明,适量的铝和适度的酸雨有利于茶树生物量的积累,较高的铝和较高酸度酸雨不利于茶树生物量的积累.随着铝处理浓度的增加,茶树叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)先增加后下降.随着酸雨强度的增加,SOD、POD、CAT和APX总体上增加,在较低浓度铝处理下,酸雨加剧SOD、POD、CAT和APX的增加,存较高铝浓度(30 mg/L)处理下,酸雨加剧SOD、POD、CAT和APX的下降.10 mg/L铝浓度处理茶树叶片超氧阴离子产生速率(O2-)和丙二醛(MDA)含量与无铝处理的相比没有明显差异,随着铝处理浓度的增加其O2-产生速率和MDA含量增加.酸雨强度对茶树叶片O2-产生速率和MDA含量没有明显影响.酸雨加剧铝引起茶树叶片O2-产生速率和MDA积累的增加.随着铝处理浓度的增加,茶树叶片脯氨酸含量增加.而酸雨单独作用对脯氨酸含量没有明显影响,但酸雨加剧铝对茶树叶片脯氨酸积累的增加.随着铝处理浓度的增加,茶树叶片可溶性糖含量先增加后下降.pH 3.0的酸雨明显提高茶树叶片可溶性糖含量.结果表明,茶树可通过提高抗氧化酶活性和一些渗透调节物质(脯氨酸和可溶性糖)增强对酸雨和低浓度铝的适应性和耐受能力.高浓度的铝(30 mg/L)损伤茶树抗氧化系统,减少一些抗性物质的合成,影响其生长,而酸雨加剧高铝对茶树的伤害.