Effects of glyphosate on the growth, development, and physiological functions of silkworm, Bombyx mori. Issue 2 (30th May 2022)

• Record Type: Journal Article
• Authors: Feng, Piao; Dai, Minli; Yang, Jin; Wang, Yuanfei; Mao, Tingting; Su, Wujie; Li, Fanchi; Sun, Haina; Wei, Jing; Li, Bing
• Is Part Of: Archives of insect biochemistry and physiology. Volume 111:Issue 2(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-30
• Subjects: Bombyx mori -- glyphosate -- midgut -- oxidative stress; Insects -- Physiology -- Periodicals; Insect biochemistry -- Periodicals; 595.701572
• DOI: 10.1002/arch.21919
• Languages: English
• ISSNs: 0739-4462

Abstract

Abstract: Glyphosate is an herbicide widely used worldwide, but whether it is safe to nontarget organisms is controversial. In this study, the lepidopteran model insect silkworm was used to investigate the effects of glyphosate residues. The LC 50 (72 h) of glyphosate on silkworm was determined to be 14875.98 mg/L, and after exposure to glyphosate at 2975.20 mg/L (a concentration comparable to that used for weed control in mulberry fields), silkworm growth was inhibited by 9.00%, total cocoon weight was lowered by 10.53%, feed digestibility was decreased by 7.56%, and the activities of alpha‐amylase and trypsin were reduced by 10.41% and 21.32%, respectively. Pathological analysis revealed that glyphosate exposure led to significantly damaged midgut, along with thinner basal layer, shedding microvilli, blurred cytoplasmic membrane, and appearance of vacuoles. Exposure to glyphosate also led to accumulation of peroxides in the intestinal tissue; the messenger RNA transcription of SOD, Cu/Zn‐SOD, and Mn‐SOD was all significantly upregulated by glyphosate treatment for 24 h, while CAT transcription was increased at 24, 48, and 72 h. The activity of SOD was increased significantly at 24 h, while significant activity changes were observed for CAT at 72 and 96 h. These results indicated that exposure to glyphosate caused oxidative stress in the midgut of silkworm and affected the midgut's physiological function. This study provides important insights in evaluating the impact of glyphosate residues in the environment on nontarget organisms. Abstract : In the present study, we investigated the effects of glyphosate on the lepidopteran model insect silkworm. We found that exposure to glyphosate caused oxidative stress in the midgut of silkworm larvae and affected midgut physiological function. This result provides important insights into the potential impact of environmental residues of glyphosate on nontarget organisms. HIGHLIGHTS: The LC 50 (72 h) of glyphosate on Bombyx mori was 14875.98 mg/L. Glyphosate was found to have low toxicity to silkworms. Low doses of glyphosate caused oxidative damage to the silkworm midgut.