香蒲对淹水生境的适应性模拟实验

Simulation Experiment on Adaptation of Typha orientalis to Flooded Habitat

为了探讨香蒲(Typha orientalis)对淹水生境的适应性,设置了0 cm、10 cm、20 cm、30 cm、40 cm、50 cm和60 cm的淹水深度,于2018年3月25日~7月22日,在鄱阳湖湿地与流域研究教育部重点实验室阳光房内,进行了120 d的模拟淹水实验,测量各淹水深度下香蒲的株高、基径、叶片特征和根的生物量等生长指标,测定光合色素含量和抗氧化酶活性等生理指标,研究香蒲对淹水生境的适应性。研究结果表明,当淹水深度为0~40 cm时,淹水对香蒲的生长影响较小,当淹水深度为50 cm时,在实验进行84 d后,香蒲接近死亡,当淹水深度为60 cm时,在实验进行60 d后,香蒲死亡;当淹水深度为20 cm时,在实验的第120天,香蒲根的生物量最大,为9.97 g/株;当淹水深度为10 cm或20 cm时,在实验的第60天,香蒲叶片中的叶绿素a、叶绿素b和类胡萝卜素含量都达到峰值,分别为1.48 mg/g、0.47 mg/g和0.39 mg/g;0~40 cm淹水深度下的香蒲叶片中的光合色素含量明显偏高;当淹水深度为20 cm或30 cm时,在实验的第90天,香蒲叶片中的超氧化物歧化酶、过氧化物酶和过氧化氢酶活性都达到峰值,分别为275.91 U/g、196.10 U/(g·min)和123.67 U/(g·min);淹水深度和淹水时长对香蒲株高、叶片特征、叶绿素含量、类胡萝卜素含量和抗氧化酶活性表现出交互作用(n=21,p<0.01)。香蒲是一种相对耐淹的植物,能较长时间在淹水深度不超过40 cm的条件下生长,其对50~60 cm的淹水深度可以耐受60 d左右。

In order to investigate the adaptation of Typha orientalis to flooded habitat, the flooding depths of 0 cm, 10 cm, 20 cm, 30 cm, 40 cm, 50 cm and 60 cm were set up by taking Typha orientalis seedlings as research objects through simulated flooding experiments from March 25 to July 22, 2018. The experiment of 120 days was conducted in the greenhouse of Key Laboratory of Poyang Lake Ecological Environment and Resource Development to study the the adaptation of Typha orientalis to flooded habitat. The growth indexes including plant height, root diameter, leaf characteristics and root biomass and the physiological indexes including photosynthetic pigment contents and antioxidant enzyme activity were analyzed under different flooding depths. The results showed that the flooding depth of 0-40 cm had little effect on the growth of Typha orientalis. When the flooding depth was 50 cm, Typha orientalis was close to death after 84 days of experiment.When the flooding depth was 60 cm, Typha orientalis died after 60 days. When the flooding depth was 20 cm,the root biomass was the highest on the 120 th day which was 9.97 g/plant. When the flooding depth was 10 cm or 20 cm, the contents of chlorophyll-a, chlorophyll-b and carotenoids were the highest on the 60 th day,which were 1.48 mg/g, 0.47 mg/g and 0.39 mg/g respectively. Photosynthetic pigment contents in leaves of Typha orientalis under the flooding depth of 0-40 cm were significantly higher than those under 50-60 cm.When the flooding depth was 20 cm or 30 cm, superoxide dismutase activity, peroxidase activity and catalase activity were the highest on the 90 th day, which were 275.91 U/g, 196.10 U/(g·min) and 123.67 U/(g·min) respectively. The flooding depth and the submergence time showed an interaction on plant height, leaf characteristics, chlorophyll contents, carotenoids contents and antioxidant enzymes(n=21, p<0.01). Typha orientalis was a relatively flood-tolerant plant that could grow for a long time under the flooding depth of less than 40 cm, and could stand for about 60 days under 50-60 cm of flooding depth.