Kemprai Phirose, Bora Pranjit Kumar, Saikia Siddhartha Proteem, Haldar Saikat
Agrotechnology and Rural Development Division, CSIR-North East Institute of Science and Technology (NEIST), Jorhat, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
Pest Manag Sci. 2023 Nov;79(11):4451-4462. doi: 10.1002/ps.7645. Epub 2023 Jul 20.
Many essential oils and their constituent volatile organic compounds are known to be phytotoxic and potential bioherbicides. This study aims to investigate the phytotoxicity of propenylbenzene-rich essential oils and identify active molecule(s) therein.
Five commercially available propenylbenzene-rich oils were screened, of which betel (Piper betle L.) oil was identified as a potent natural phytotoxin. It dose-dependently inhibited wheatgrass (Triticum aestivum) seed germination and growth in water and agar medium with half maximal inhibitory concentration (IC ) in the range 23.2-122.7 μg mL . Phytotoxicity-guided fractionation and purification revealed chavibetol as the major and most potent phytotoxic constituent of betel oil, followed by chavibetol acetate. A structure-activity relationship study involving 12 propenylbenzenes indicated the structural and positional importance of aromatic substitutions for the activity. Furthermore, the phytotoxic efficacy of chavibetol was established against wheatgrass germination and growth in water (IC 15.8-53.4 μg mL ), agar (IC 34.4-53.6 μg mL ) and aerial (IC 1.7-4.5 mg L ) media with a more pronounced effect on the radicle. Also, in open phytojars, chavibetol efficiently inhibited the growth of 3-7-day-old bermudagrass (Cynodon dactylon) seedlings when sprayed directly (IC 2.3-3.4 mg jar ) or supplemented in agar (IC 116.6-139.1 μg mL ). The growth of pre-germinated green amaranth (Amaranthus viridis) was inhibited more effectively in both application modes (1.2-1.4 mg jar and IC 26.8-31.4 μg mL respectively).
The study concluded betel oil as a potent phytotoxic herbal extract and its major constituent chavibetol as a promising volatile phytotoxin for the future management of weeds in their early phase of emergence. © 2023 Society of Chemical Industry.
许多精油及其挥发性有机化合物成分已知具有植物毒性，是潜在的生物除草剂。本研究旨在调查富含丙烯基苯的精油的植物毒性，并确定其中的活性分子。
对五种市售富含丙烯基苯的油进行了筛选，其中荜澄茄（Piper betle L.）油被鉴定为一种强效天然植物毒素。它在水和琼脂培养基中剂量依赖性地抑制小麦草（Triticum aestivum）种子萌发和生长，半数最大抑制浓度（IC）在23.2 - 122.7μg/mL范围内。通过植物毒性导向的分级分离和纯化，发现丁香酚是荜澄茄油的主要且最有效的植物毒性成分，其次是乙酸丁香酚酯。一项涉及12种丙烯基苯的构效关系研究表明，芳香取代基的结构和位置对活性具有重要意义。此外，丁香酚对小麦草在水（IC为15.8 - 53.4μg/mL）、琼脂（IC为34.4 - 53.6μg/mL）和气生（IC为1.7 - 4.5mg/L）培养基中的萌发和生长具有植物毒性作用，对胚根的影响更为显著。同样，在开放式植物培养罐中，直接喷洒（IC为2.3 - 3.4mg/罐）或添加到琼脂中（IC为116.6 - 139.1μg/mL）时，丁香酚能有效抑制3 - 7日龄狗牙根（Cynodon dactylon）幼苗的生长。在两种施用方式下，预发芽的绿苋（Amaranthus viridis）的生长均受到更有效抑制（分别为1.2 - 1.4mg/罐和IC为26.8 - 31.4μg/mL）。
该研究得出结论，荜澄茄油是一种强效植物毒性草药提取物，其主要成分丁香酚是一种有前景的挥发性植物毒素，可用于杂草出苗早期的未来管理。©2023化学工业协会。
