菲对秀丽隐杆线虫、中杆属和拟丽突属线虫毒性效应研究

摘要

A gnotobiotic microcosm experiment was conducted to study the toxic effects of phenanthrene (PHE) on three nematodes—Caenorhabditis elegans,Mesorhabditissp.and Acrobeloidessp., alsothe possibility of PHE depletion by the nematodes were examined. The results showed that the survival rates of these three nematodes decreased gradually with PHE concentration increased. Without PHE exposure,Caenorhabditis eleganscould reproduce within 48 hours and 5 mg/L PHE could inhibit the reproduction of Caenorhabditis elegans. While no reproductive patterns was observed with the Mesorhabditis sp. and Acrobeloidessp.due to their longer generation time. After comparing the relative mortality at 24h exposure, the tolerance order of those nematode was Mesorhabditis sp.≥Caenorhabditis elegans≥Acrobeloides sp., and the tolerance of Caenorhabditis elegans reduced gradually with the increased PHE concentration. After 48h exposure,Mesorhabditis sp. still had a higher tolerance than Acrobeloidessp., while after 72h exposure, both of them showed similar tolerance to PHE. All nematodes lost the head swing ability after PHE exposure, and the body length of Caenorhabditis elegans and Acrobeloidessp. reduced gradually with the increase of PHE concentration. All nematodes could help to facilitate the depletion of PHE, and no significant difference was found among three nematodes. In conclusion, PHE could restrain the survival, growth and activity of these nematodes, and inhibit the reproduction of the Caenorhabditis elegans.The survival rates of the nematodes were significantly influenced by nematode species, exposure time, PHE concentrations and their interactions.Mesorhabditis sp. showed the highest resistance to PHE pollution. All the three nematodes could contribute to the depletion of phenanthrene in solution.%采用悉生培养系统,研究不同浓度菲对秀丽隐杆线虫、拟丽突属与中杆属线虫的毒性效应,以及3种线虫对菲的去除作用.结果表明:①随着菲浓度的增加,3种线虫存活率逐渐降低.秀丽隐杆线虫在不添加菲的处理中,48 h内出现繁殖,而在添加菲的处理中,即使在最低浓度5 mg/L下,繁殖现象也会消失.中杆属与拟丽突属线虫由于世代时间较长,在本试验周期内均未出现繁殖现象.②暴露24 h时,比较不同浓度菲处理下线虫的相对死亡率,得到3种线虫的耐性依次为中杆属线虫≥秀丽隐杆线虫≥拟丽突属线虫,且随菲浓度的增加,秀丽隐杆线虫耐性水平逐渐降低;暴露48 h时中杆属线虫耐性依旧高于拟丽突属,而72 h时中杆属与拟丽突属线虫的耐性趋于一致.③3种线虫受菲胁迫后均失去头部正常摆动能力,且秀丽隐杆线虫与拟丽突属线虫体长随菲浓度的增加而逐渐降低.④不同种类线虫的添加均能促进菲的去除,不同线虫之间无显著差异.因此,菲会显著抑制3种线虫的存活率和生长发育,抑制秀丽隐杆线虫的繁殖.线虫的存活率受线虫种类、暴露时间、菲浓度及其交互作用的影响显著,其中中杆属线虫对菲的综合耐性最强,3种线虫均能促进溶液中菲的去除.