Phytotoxicity of Essential Oils: Opportunities and Constraints for the Development of Biopesticides. A Review

Abstract

The extensive use of chemical pesticides leads to risks for both the environment and human health due to the toxicity and poor biodegradability that they may present. Farmers therefore need alternative agricultural practices including the use of natural molecules to achieve more sustainable production methods to meet consumer and societal expectations. Numerous studies have reported the potential of essential oils as biopesticides for integrated weed or pest management. However, their phytotoxic properties have long been a major drawback for their potential applicability (apart from herbicidal application). Therefore, deciphering the mode of action of essential oils exogenously applied in regards to their potential phytotoxicity will help in the development of biopesticides for sustainable agriculture. Nowadays, plant physiologists are attempting to understand the mechanisms underlying their phytotoxicity at both cellular and molecular levels using transcriptomic and metabolomic tools. This review systematically discusses the functional and cellular impacts of essential oils applied in the agronomic context. Putative molecular targets and resulting physiological disturbances are described. New opportunities regarding the development of biopesticides are discussed including biostimulation and defense elicitation or priming properties of essential oils.

Curcuma longa L. Rhizome Essential Oil from Extraction to Its Agri-Food Applications. A Review

“…As a result, sustainability has become an increasingly important subject in the agri-food industry. The characteristics of certain natural products, especially essential oils (zero waste), have become a matter of study as sustainable alternatives [ 171 , 172 , 173 , 174 , 175 , 176 ]. Amongst them, C. longa rhizome oil can take part in the safer and eco-friendly emergent agri-food industry due to its promising antimicrobial, herbicidal and antioxidant activities ( Figure 2 ).…”

Essential Oil of Deverra tortuosa Aerial Parts: Detailed Chemical Profile, Allelopathic, Antimicrobial, and Antioxidant Activities

“…These EOs stored in various organs of the plant such as leaf, flower, stem, root, and fruit. The EOs were reported to possess various biological activities, such as antimicrobial, antioxidant, allelopathic, anticancer, anti‐inflammatory, and insect repellent [1–6] …”

Biopesticide Trunk Injection Into Apple Trees: A Proof of Concept for the Systemic Movement of Mint and Cinnamon Essential Oils

“…A well-studied formulation could, on the one hand, counter the high volatility of EOs and ensure the prolonged release of the active substance and, on the other hand, attenuate potential phytotoxic effects ( Moretti et al, 2002 ; Maes et al, 2019 ). EOs can impact many plant physiological processes (water status alteration, membrane integrity, respiration, and photosynthesis inhibition) through diverse modes of action, such as reactive oxygen species (ROS) induction and enzymatic or phytohormone regulation ( Werrie et al, 2020 ). In this regards, chlorophyll fluorescence has been proven useful to evaluate plant vitality and response to abiotic stress ( Kalaji et al, 2016 ).…”