皇竹草对土壤阿特拉津的降解特性

Effect of Pennisetum hydridum Degrading Atrazine in Soil

为了探明种植皇竹草(Pennisetum hydridum)对土壤阿特拉津降解的促进作用,通过盆栽试验研究了皇竹草对土壤阿特拉津的降解动态、转移特征以及土壤阿特拉津残留浓度与土壤相关酶活性的关系。结果表明:与未种植皇竹草相比,种植皇竹草土壤阿特拉津降解率明显提高,皇竹草对未灭菌和灭菌土壤阿特拉津的降解率分别提高52.84和42.38百分点;与未种植皇竹草处理相比,灭菌和未灭菌条件下种植皇竹草处理阿特拉津在土壤中的半衰期可分别缩短64.35和53.21 d;土壤中阿特拉津被皇竹草吸收后逐步由地下部分向地上部分转移,随着培养时间的延长,转移系数变大;土壤中阿特拉津残留浓度与土壤过氧化氢酶、过氧化物酶、转化酶和多酚氧化酶活性呈显著负相关(P<0.05或P<0.01)。认为种植皇竹草有助于阿特拉津的降解。

A pot experiment was carried out in order to understand effects of Pennisetum hydridum on atrazine degradation, dynamics of the degradation and translocation of the substance, and relationships between concentration of atrazine residue and activities of relevant soil enzymes in the soil. Results show that atrazine degradation rate significantly increased in pots planted with P. hydridum by 52.84 percentage points in nonsterilized pots and by 42.38 percentage points in steri lized pots. The halflife of soil atrazine in sterilized and non sterilized pots planted with P. hydridum was significantly shortened, by 64.35 and 53.21 days, respectively. Atrazine in soil was absorbed by P. hydridum, and then gradually transferred from roots to shoots. With the plants growing on and on, transfer coefficient of the substance increased. Significant negative relationships were observed between concentration of atrazine residue in the soil and activities of soil catalase, peroxidase, invertase and polyphenol oxidase. All these findings indicate that planting P. hydridum is conducive to degradation of atrazine in the soil.