不同粒径微塑料对红树林线虫生活史的影响

Effects of Different Particle Sizes of Microplastics on the Life Cycle of Mangrove Nematodes

摘要: 本文利用玉米培养基成功培养红树林线虫Viscosia heterolaima sp，并观察到线虫的胚胎发育及胚后发本文对线虫Viscosia heterolaima sp进行暴露不同粒径微塑料暴露，以致死率、怀卵数、胚胎发育时间、后代数目等评估不同粒径的微塑料颗粒对线虫生活史的影响，发现致死率与微塑料的浓度无关，与微塑料的粒径有关，粒径(0.1、1.0、3.0、5.0) μm微塑料颗粒对线虫Viscosia heterolaima sp死亡率产生显著影响，其中，3 μm粒径微塑料对线虫成活率影响最大平均致死率为24.17%，与对照组差异显著(P < 0.01)，浓度2 mg∙L⁻¹粒径为0.1、1.0、3.0和5.0 µm的微塑料均能降低线虫的怀卵数，其中，粒径3 μm线虫怀卵数影响最大(抑制率为36.57%)，与对照组差异极显著(P < 0.01)；微塑料处理组对线虫胚胎1细胞、2细胞、多细胞期、囊胚期、原肠胚期、蠕虫的发育时间明显延长，(0.1、1.0、3.0、5.0) μm微米微塑料处理组胚胎发育持续时间分别为65.05 ± 1.19 hr，66.39 ± 0.94hr，69.04 ± 0.89 hr，64.49 ± 1.28 hr，3.0 μm微塑料处理对线虫胚胎发育持续时间影响最大，与对照组差异极显著(P < 0.01)；将线虫暴露于2 mg∙L⁻¹、0.1~5.0 µm的微塑料溶液后，微塑料颗粒主要分布在线虫Viscosia heterolaima sp肠道中，各粒径微塑料在线虫体内差异明显。其中，3.0 μm的微塑料颗粒在线虫Viscosia heterolaima sp体内的荧光强度最强；不同粒径微塑料都能降低线虫Viscosia heterolaima sp后代数目，使线虫的后代数目显著降低，抑制率达15.37%~40.35%。

Abstract: In this study, the effect of microplastic particles on the life cycle of nematodes, Viscosia heterolaima sp, was evaluated by fatality rate, number of eggs, embryonic development time, and number of offspring. It was found that the fatality rate was not related to the concentration of the microplastics, but to the particle size of the microplastics. The particle size (0.1, 1.0, 3.0, 5.0) of the microplastics had a significant effect on the fatality rate of Viscosia heterolaima sp. The average fatality rate was 24.17% (P < 0.01). 1.0, 3.0 and 5.0 m microplastics could reduce the number of eggs of nematodes, and the effect of 3 μm microplastics on the number of eggs of nematodes was the greatest (inhibition rate was 36.57%), which was significantly different from the control group (P < 0.01). The development time of 1-cell, 2-cell, multicellular, blastocyst, gastrula and helminth stage of nematode embryos treated with microplastics was significantly prolonged, and the development duration of embryos treated with (0.1., 1.0, 3.0, 5.0) μm microplastics was 65.05 ± 1.19 hr, respectively. Hr, 66.39 ± 0.94 hr, 69.04 ± 0.89 hr, 64.49 ± 1.28 hr, 3.0 μm Microplastic treatment had the greatest effect on the duration of embryo development of nematode, and the difference was very significant (P < 0.01). After the nematodes were exposed to 2 mg·L⁻¹, 0.1~5.0 μm microplastic solution, the microplastic particles were mainly distributed in the gut of the nematode Viscosia heterolaima sp. Among them, the fluorescence intensity of 3.0 μmmicroplastic particles was the strongest in Viscosia heterolaima sp. The number of progeny of nematode Viscosia heterolaima sp was significantly reduced by microplastics with different particle size, and the inhibition rate was 15.37%~40.35%.