家蚕,乐果,生殖毒性,氧化应激,形态结构," /> 家蚕,乐果,生殖毒性,氧化应激,形态结构,"/>  Bombyx mori,dimethoate,reproductive toxicity,oxidative stress,morphological structure,"/> <span style="font-size:13.3333px;">乐果对家蚕生殖腺及氧化应激反应的影响</span>

昆虫学报 ›› 2019, Vol. 62 ›› Issue (10): 1186-1196.doi: 10.16380/j.kcxb.2019.10.007

• 研究论文 • 上一篇    下一篇

乐果对家蚕生殖腺及氧化应激反应的影响

石敏, 李冠楠, 郑茜, 刘凤丹, 赵珊, 蔡苗, 朱勇*   

  1. (西南大学生物技术学院, 农业农村部蚕桑生物学与遗传育种重点实验室, 重庆400715)
  • 出版日期:2019-10-20 发布日期:2019-10-14

Effects of dimethoate on the gonads and oxidative stress response in the silkworm, Bombyx mori

SHI Min, LI Guan-Nan, ZHENG Xi, LIU Feng-Dan, ZHAO Shan, CAI Miao, ZHU Yong*    

  1. (State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing 400715, China)
  • Online:2019-10-20 Published:2019-10-14

摘要: 【目的】农药施加不当导致环境污染严重,已成为蚕桑业发展面临的紧迫问题。本研究旨在评估大田喷洒有机磷农药乐果污染间作桑园可能导致对家蚕Bombyx mori正常发育的影响,以分析乐果对家蚕生殖腺的毒理损伤影响。【方法】以文献报道的乐果对家蚕幼虫的LD50为400 mg/L作为参考依据,给家蚕5龄幼虫添食不同浓度(0, 50, 100, 200和400 mg/L)乐果溶液浸叶处理的桑叶,测定乐果处理后5龄幼虫茧质和体重,雌、雄幼虫生殖腺中乐果残留含量和H2O2含量,抗氧化酶(SOD和CAT)活性及其mRNA表达。【结果】结果显示,乐果处理后家蚕5龄幼虫茧质和体重以及雌、雄幼虫生殖腺中乐果残留含量均具有浓度效应关系。100~200 mg/L乐果浓度添食下,雌雄幼虫生殖腺中H2O2含量与对照(清水)相比均显著上升。随着添食浓度的增加,SOD和CAT活性都出现先降低后升高的趋势,但均低于对照组。sodcat的mRNA表达水平与相应的酶活性具有正相关性。通过HE染色以及生精囊的体外培养,观察到在乐果处理后雌、雄幼虫生殖腺的形态结构发生变化,表现为形态畸形,细胞内空泡增大,生殖细胞数目相对减少,且随浓度的增加,生殖腺损伤越严重。【结论】本研究结果说明,采用乐果对家蚕的LD50以下浓度溶液浸叶添食于5龄幼虫,对家蚕生殖腺发育有毒理损伤的影响,这为从蚕业生产角度全面禁止大田使用乐果和加强农业生产区划管理提供了依据。

关键词: 家蚕')">家蚕, 乐果, 生殖毒性, 氧化应激, 形态结构

Abstract: 【Aim】 Due to improper application of pesticides, environmental pollution has become an important obstacle to the development of sericulture. This study aims to assess the effects of field application of the organophosphorus pesticide dimethoate on the silkworm, Bombyx mori, so as to elucidate its damage mechanism to the gonads of this insect. 【Methods】 According to the LD50 value of dimethoate to B. mori larvae (400 mg/L) reported in the literature, the 5th instar larvae of B. mori were fed with mulberry leaves that had been soaked in different concentrations (0, 50, 100, 200 and 400 mg/L) of dimethoate solution. After treatment with dimethoate, the cocoon quality and body weight of the 5th instar larvae, and the residual content of dimethoate and the H2O2 content, the activities of antioxidant enzymes and the mRNA expression levels of these enzymes in the gonads of both male and female larvae were determined. 【Results】 The results showed that the cocoon quality and body weight of the 5th instar larvae of B. mori and the residual content of dimethoate in the gonads of both female and male larvae after treatment with dimethoate showed the concentration-effect relationship. The H2O2 content in the gonads of both female and male larvae treated with 100-200 mg/L dimethoate significantly increased as compared with that in the control (treated with water). With the increase of the concentration of dimethoate, both SOD and CAT activities showed a trend of decreasing first and then increasing, and both of them were lower than those in the control group. And there was a positive correlation between the SOD or CAT activity and the mRNA expression levels of the corresponding gene. After HE staining and in vitro culture of the spermatogenic sac of the silkworm, the morphological structure of gonads in male and female larvae after treatment with dimethoate showed obvious change, with their morphology abnormal, intracellular vacuoles increased, and the number of germ cells reduced relatively. Besides, with the increase in the concentration of dimethoate, its damage to gonads became more serious. 【Conclusion】 The results of this study suggest that using leaves that have been soaked in dimethoate solution at a concentration below LD50 to feed the 5th instar larvae of B. mori have toxic effects on the development of gonads of B. mori, and this provides a basis for banning the use of dimethoate in the field and strengthening the regional management of agricultural production.

Key words:  Bombyx mori')"> Bombyx mori, dimethoate, reproductive toxicity, oxidative stress, morphological structure