Mengjun Zhao, Feiran Chen, Xiaona Li, Chuanxi Wang, Xuesong Cao, Liya Jiao, Le Yue and Zhenyu Wang
{"title":"Rhizosphere regulation with cerium oxide nanomaterials promoted carrot taproot thickening†","authors":"Mengjun Zhao, Feiran Chen, Xiaona Li, Chuanxi Wang, Xuesong Cao, Liya Jiao, Le Yue and Zhenyu Wang","doi":"10.1039/D4EN00334A","DOIUrl":null,"url":null,"abstract":"<p >Nanomaterials (NMs) provide great potential for sustainable development by regulating rhizosphere processes to improve crop productivity. The edible parts of rhizome crops have direct contact with the rhizosphere, which may lead to a more direct positive effect of NMs and rhizosphere interaction on the growth and development of rhizome crops. Here, 50 mg kg<small><sup>−1</sup></small> cerium oxide (CeO<small><sub>2</sub></small>) NMs had the greatest promotion on carrot growth, and 5 days was the initial time for promoting taproot thickening. The application of CeO<small><sub>2</sub></small> NMs to soil first stimulated the secretion of organic acids, amino acids, fatty acids, phenols, and carbohydrates (such as citric acid, asparagine, and alpha-linolenic acid), as well as growth regulators indole-3-acetic acid (IAA) and jasmonic acid, from the roots to the rhizosphere. This resulted in a significant increase in the relative abundances of <em>Altererythrobacter</em>, <em>Gemmatimonas</em>, <em>Pseudomonas</em>, <em>Sphingomonas</em> and <em>Chryseolinea</em> by 16.2–61.4%, thereby enhancing nutrient accumulation and elevating IAA levels in taproots. Meanwhile, CeO<small><sub>2</sub></small> NMs were effectively absorbed by the seedling roots and transferred to the leaves. The internalized CeO<small><sub>2</sub></small> NMs induced cell division in the taproot vascular cambium by increasing levels of IAA and cytokinins by 22.2% and 33.7%, respectively. The responsive differentially expressed genes were mainly involved in the cell wall and cell division, carbohydrate metabolism, and phytohormone signal transduction pathways. Furthermore, photosynthesis was enhanced, leading to a significant increase in sucrose and starch content by 55.3% and 71.7%, respectively. The integration of rhizobacteria, phytohormones, and gene regulations synergistically promoted carrot taproot thickening. This study contributes to our understanding of rhizosphere regulation in nano-enabled agriculture.</p>","PeriodicalId":73,"journal":{"name":"Environmental Science: Nano","volume":null,"pages":null},"PeriodicalIF":5.8000,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Science: Nano","FirstCategoryId":"6","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/en/d4en00334a","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Nanomaterials (NMs) provide great potential for sustainable development by regulating rhizosphere processes to improve crop productivity. The edible parts of rhizome crops have direct contact with the rhizosphere, which may lead to a more direct positive effect of NMs and rhizosphere interaction on the growth and development of rhizome crops. Here, 50 mg kg−1 cerium oxide (CeO2) NMs had the greatest promotion on carrot growth, and 5 days was the initial time for promoting taproot thickening. The application of CeO2 NMs to soil first stimulated the secretion of organic acids, amino acids, fatty acids, phenols, and carbohydrates (such as citric acid, asparagine, and alpha-linolenic acid), as well as growth regulators indole-3-acetic acid (IAA) and jasmonic acid, from the roots to the rhizosphere. This resulted in a significant increase in the relative abundances of Altererythrobacter, Gemmatimonas, Pseudomonas, Sphingomonas and Chryseolinea by 16.2–61.4%, thereby enhancing nutrient accumulation and elevating IAA levels in taproots. Meanwhile, CeO2 NMs were effectively absorbed by the seedling roots and transferred to the leaves. The internalized CeO2 NMs induced cell division in the taproot vascular cambium by increasing levels of IAA and cytokinins by 22.2% and 33.7%, respectively. The responsive differentially expressed genes were mainly involved in the cell wall and cell division, carbohydrate metabolism, and phytohormone signal transduction pathways. Furthermore, photosynthesis was enhanced, leading to a significant increase in sucrose and starch content by 55.3% and 71.7%, respectively. The integration of rhizobacteria, phytohormones, and gene regulations synergistically promoted carrot taproot thickening. This study contributes to our understanding of rhizosphere regulation in nano-enabled agriculture.
期刊介绍:
Environmental Science: Nano serves as a comprehensive and high-impact peer-reviewed source of information on the design and demonstration of engineered nanomaterials for environment-based applications. It also covers the interactions between engineered, natural, and incidental nanomaterials with biological and environmental systems. This scope includes, but is not limited to, the following topic areas:
Novel nanomaterial-based applications for water, air, soil, food, and energy sustainability
Nanomaterial interactions with biological systems and nanotoxicology
Environmental fate, reactivity, and transformations of nanoscale materials
Nanoscale processes in the environment
Sustainable nanotechnology including rational nanomaterial design, life cycle assessment, risk/benefit analysis