Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India.
Department of Botany and Microbiology, Central Laboratory, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia.
Chemosphere. 2021 Sep;278:130372. doi: 10.1016/j.chemosphere.2021.130372. Epub 2021 Apr 2.
In recent times, agricultural practices mainly rely on agrochemicals and pesticides to safe-guard edible crops against various pests and to ensure high yields. However, their indiscriminate use may cause severe environmental hazards that directly and negatively affect soil microorganisms and crop productivity. Considering these, present study was aimed to assess the toxicity of carbamate pesticides namely carbamoyl (CBL), methomyl (MML) and carbofuran (CBN) using bacterial and plant (Vigna mungo L.) bioassays. All pesticide doses (25-100 μg mL) showed negative effect on bacteria as well as plant. Growth, morphology, survival, cellular respiration and inner membrane permeability of Sinorhizobiumsaheli was hampered when exposed to pesticides. Pesticide induced morphological changes viz. aberrant margins; cellular cracking and distortion/damage in S. saheli were obvious under scanning electron microscope (SEM). The 100 μgCBNmL had maximum inhibitory effect and it reduced survivability of S. saheli by 75%. In addition, biofilm formation ability of S. saheli was inhibited in a pesticides-dose dependent manner and it was statistically (p ≤ 0.05) significant. Pesticides indorsed significant changes in biomarker enzymatic assays and oxidative stress parameters towards S. saheli. Furthermore, at 100 μgCBNmL, germination efficiency, root, shoot length, plant survival and tolerance index of V. mungo were decrease by 50, 75, 65, 70 and 66%, respectively over control. Staining of pesticide treated roots with fluorescently labeled dyes propidium iodide (PI) and acridine orange (AO) showed increased oxidative stress, ROS generation and membrane permeability as revealed under confocal laser scanning microscope (CLSM). Furthermore, stressor metabolites and antioxidant enzymes in plant seedlings were progressively enhanced with increasing concentration of pesticides. Conclusively, present finding bestow an insights into a mechanistic approach of carbamate pesticide induced phyto, morpho and cellular toxic effects towards soil bacterium as well as plant with forthcoming implications for designing the pesticides to reduce their toxic/harmful effects.
近年来，农业生产主要依赖于农用化学品和农药来保护食用作物免受各种害虫的侵害，并确保高产量。然而，它们的滥用以会对土壤微生物和作物生产力产生直接的负面影响，从而造成严重的环境危害。考虑到这些，本研究旨在使用细菌和植物（绿豆）生物测定法评估氨基甲酸酯类农药，即氨基甲酰（CBL）、灭多威（MML）和克百威（CBN）的毒性。所有农药剂量（25-100μg/mL）对细菌和植物都表现出负面影响。暴露于农药会阻碍苜蓿中华根瘤菌的生长、形态、存活、细胞呼吸和内膜通透性。在扫描电子显微镜（SEM）下，农药诱导的形态变化，如异常边缘；细胞破裂和变形/损伤在 S. saheli 中是显而易见的。100μgCBNmL 具有最大的抑制作用，它使 S. saheli 的存活率降低了 75%。此外，S. saheli 的生物膜形成能力以农药剂量依赖的方式受到抑制，并且在统计学上（p≤0.05）是显著的。农药会引起 S. saheli 生物标志物酶测定和氧化应激参数的显著变化。此外，在 100μgCBNmL 下，绿豆的发芽效率、根长、茎长、植物存活率和耐受力指数分别比对照降低了 50%、75%、65%、70%和 66%。用荧光标记的碘化丙啶（PI）和吖啶橙（AO）对农药处理过的根进行染色，显示出氧化应激、ROS 生成和膜通透性的增加，这在共聚焦激光扫描显微镜（CLSM）下得到了证实。此外，随着农药浓度的增加，植物幼苗中的应激代谢物和抗氧化酶也逐渐增加。总之，本研究结果深入了解了氨基甲酸酯类农药对土壤细菌和植物的植物毒性、形态毒性和细胞毒性的机制方法，对设计减少其毒性/有害影响的农药具有重要意义。
