硝化抑制剂双氰胺对葛仙米的生物毒性

摘要：

为了准确地评估硝化抑制剂双氰胺(DCD)对固氮蓝藻的生物毒性，为农田合理应用硝化抑制剂和固氮蓝藻提供理论依据，选取稻田可食用固氮蓝藻一拟球状念珠藻(Nostoc Sphaeroides,俗名葛仙米),从生长、光合系统、固氮活性和氧化一抗氧化系统等方面，研究了田面水培养条件下DCD对葛仙米的生物毒性,结果表明，田面水中DCD质量浓度为240mg·L^-1时.显著抑制葛仙米的生长.DCD胁迫能降低葛仙米藻蓝蛋白(PC)含量，损伤光合系统II，诱导细胞内活性氧(ROS)含量升高.葛仙米胞内抗氧化防御系统可以消除低质量浓度DCD引起的氧化胁迫，当DCD质量浓度达到300mg·L^-1时，藻细胞受到氧化性损伤.低质量浓度的DCD可增强葛仙米的固氮活性，但是当其质量浓度≥240mg·L^-1时，显著抑制该藻的固氮活性.研究结果表明，培育葛仙米的稻田，田面水中 DCD质量浓度建议不超过120mg·L^-1.

In order to accurately evaluate bio-toxicity of nitrification inhibitor dicyandiamide(DCD) on diazotrophic cya-nobacteria and provide useful information on reasonable application of DCD and diazotrophic cyanobacteria in agricultural fields.this study investigated the effects of DCD on growth, photosynthesis, nitrogen-fixing activity, and the oxidative-antioxidative characteristies of an edible diazotrophic cyanobacterium Nostoe Sphaeroides in paddy flooded water. The results showed that,DCD, at a concentration of 240mg·L^-1, significantly inhibited the growth of N. Sphaeroides. And also, DCD decreased the content of phycocyanin(PC), severely damaged the PS II . and increased reactive oxygen species(ROS) in cells of N. Sphae-roides. The intracellular antioxidant defense system could dliminate oxidative stress induced by low level of DCD. However,high level of DCD(300mg·L^-1) resulted in oxidative damage on cells of N.Sphaeroides. The dinitrogen-fixing activity of N. Sphaeroides was promoted by low level of DCD. but it was significantly inhibited by DCD at a concentration of 240mg·L^-1. Based on these findings, it is recommended that the DCD concentration in paddy flooded water where N. Sphaeroides is cultivated should not exceed120mg·L^-1.

作者：

邵继海，冯丹怡，冯烨，金文熙，谭雅琪

Shao Jihai, Feng Danyi, Feng Ye, Jin Wenxi, Tan Yaqi

机构地区：

湖南农业大学环境与生态学院

引用本文：

邵继海，冯丹怡，冯烨等，硝化抑制剂双氰胺对葛仙米的生物毒性[J].河南师范大学学报(自然科学版),2026.54(4):1-8.(Shao Jihai. Feng Danyi.Feng Ye,et al. Bio-toxicity of nitrification inhibitor dicyandiamide on Nostoc sphaeroides[J].Journal of Henan Normal University(Natural Science Edition),2026,54(4):1-8.DOI:10.16366/j.cnki.1000-2367.2024.11.29.0001.)

基金：

国家自然科学基金

关键词：

生长率;光合系统;氧化 抗氧化系统;固氮酶活性

growth rate; photosynthetic system; oxidative-antioxidant system; dinitrogen-fixing enzyme activity

分类号：

Q89

硝化抑制剂双氰胺对葛仙米的生物毒性.pdf