Department of Botany, Panjab University, Chandigarh 160014, India.
Department of Environment Studies, Panjab University, Chandigarh 160014, India.
Ecotoxicol Environ Saf. 2019 Apr 30;171:863-870. doi: 10.1016/j.ecoenv.2018.12.091. Epub 2019 Jan 18.
In the present study, the essential oil (EO) of Hyptis suaveolens has been explored for the first time for its phytotoxic and cytotoxic activities. The phytotoxic activity was assessed against rice (Oryza sativa) and its major troublesome weed, Echinochloa crus-galli, under laboratory and screenhouse conditions. GC-MS analysis revealed EO to be monoterpenoid (~ 79% monoterpenes) in nature with α-phellandrene (22.8%), α-pinene (10.1%) and limonene (8.5%) as the major chemical constituents. The laboratory bioassay showed a complete growth inhibitory effect of EO (≥ 2 mg mL) towards the germination and seedling growth of E. crus-galli. However, the inhibitory effect on rice was much less (~40% inhibition). EO caused visible injury, reduction in chlorophyll content, cell viability and ultimately led to complete wilting of E. crus-galli plants. In addition, EO altered the cell division in the meristematic cells of Allium cepa as depicted by ~63% decrease in mitotic index. EO exposure induced several aberrations at chromosomal (c-mitosis, anaphase bridges, chromosomal breakage, vagrant chromosomes, and sticky chromosomes) and cytological level (cytoplasm destruction, peripheral nuclei, and bi-nucleate cells). The present study concludes that H. suaveolens EO possesses phytotoxic activity due to its mito-depressive activity, and could serve as a natural herbicide under sustainable agricultural practices.
在本研究中，首次探索了 Hyptis suaveolens 的精油（EO）的植物毒性和细胞毒性活性。在实验室和温室条件下，评估了其对水稻（Oryza sativa）及其主要杂草稗草（Echinochloa crus-galli）的植物毒性活性。GC-MS 分析表明，EO 为单萜类化合物（79%单萜类化合物），主要化学成分为α-水芹烯（22.8%）、α-蒎烯（10.1%）和柠檬烯（8.5%）。实验室生物测定表明，EO（≥2mg/mL）对稗草的萌发和幼苗生长具有完全的生长抑制作用。然而，对水稻的抑制作用要小得多（40%抑制）。EO 导致稗草植物可见损伤、叶绿素含量降低、细胞活力下降，最终导致完全萎蔫。此外，EO 改变了洋葱根尖分生细胞的细胞分裂，有丝分裂指数降低了约 63%。EO 暴露在染色体（c-有丝分裂、后期桥、染色体断裂、流浪染色体和粘性染色体）和细胞学水平（细胞质破坏、周边核和双核细胞）上诱导了几种异常。本研究得出结论，H. suaveolens EO 由于其线粒体抑制活性而具有植物毒性活性，并可在可持续农业实践中用作天然除草剂。
