Department of Vegetable Science, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China.
Department of Horticulture, Faculty of Crop Production Sciences, The University of Agriculture Peshawar, Pakistan.
Ecotoxicol Environ Saf. 2021 Jun 1;215:112132. doi: 10.1016/j.ecoenv.2021.112132. Epub 2021 Mar 17.
Aqueous garlic extracts (AGE) and garlic allelochemical diallyl disulfide (DADS) have been recently reported to bear bioactive properties to stimulate plant growth and development and alter defense-related physiology. We, therefore, performed a bioassay to study these chemicals as possible biostimulants for defense against Verticillium dahliae in eggplant seedlings. AGE and DADS were applied as a foliar application to the eggplants and samples were collected before and after pathogen inoculation at various intervals to analyze the defense mechanism. The obtained data revealed that with the application of AGE and DADS, the seedlings showed responses including activation of antioxidant enzymes, an abundance of chlorophyll contents, alteration of photosynthesis system, and accumulation of plant hormones compared to the control plants. Furthermore, the microscopic analysis of the AGE or DADS treated plants showed high variability in pathogen density within the root crown at 28 days post-inoculation. The low abundance of reactive oxygen species was noticed in AGE or DADS treated plants, which indicates that the plants were able to successfully encounter pathogen attacks. The AGE and DADS treated plants exhibited a lower disease severity index (32.4% and 24.8% vs 87.1% in controls), indicating successful defense against Verticillium infection. Our results were therefore among the first to address the biostimulatory effects of AGE or DADS to induce resistance in eggplant seedlings against V. dahliae and may be used to establish preparation for garlic-derived bioactive compounds to improve growth and defense responses of eggplants under-protected horticultural situations such as glasshouse or plastic tunnels system.
水培大蒜提取物 (AGE) 和大蒜化感二烯丙基二硫醚 (DADS) 最近被报道具有刺激植物生长和发育以及改变防御相关生理的生物活性特性。因此，我们进行了一项生物测定实验，以研究这些化学物质作为茄子幼苗防御黄萎病菌的可能生物刺激剂。AGE 和 DADS 被作为叶面喷施应用于茄子上，并在接种病原菌前后的不同时间间隔采集样本，以分析防御机制。获得的数据表明，与对照植株相比，用 AGE 和 DADS 处理的幼苗表现出包括抗氧化酶的激活、叶绿素含量的增加、光合作用系统的改变和植物激素的积累等反应。此外，用 AGE 或 DADS 处理的植株的微观分析显示，在接种后 28 天，根冠内病原菌的密度有很大的变化。在 AGE 或 DADS 处理的植株中，注意到活性氧物质的丰度较低，这表明植株能够成功地抵御病原菌的攻击。用 AGE 或 DADS 处理的植株表现出较低的病情严重指数（分别为 32.4%和 24.8%，而对照为 87.1%），表明对黄萎病菌的防御成功。因此，我们的结果是第一批研究 AGE 或 DADS 诱导茄子幼苗对黄萎病菌产生抗性的生物刺激作用的结果之一，并可用于建立大蒜衍生的生物活性化合物的制备方法，以改善在温室或塑料隧道系统等保护园艺环境下茄子的生长和防御反应。
