Rethinking biorational insecticides for pest management: unintended effects and consequences

Abstract

Biorational insecticides are composed of natural products, including animals, plants, microbes, and minerals, or are their derivates. The use of biorational products for the management of insect pests has grown intensively in recent years, which has increased their popularity and share on the insecticide global market. Much of these recent increases in the use of biorational insecticides has been derived from the generalized perception that conventional insecticides have undesirable ecological and human health impacts. However, the idea of simply replacing synthetic compounds with biorational insecticides without considering their potential unintended effects can mislead their use and reduce the market life of such pest management tools. A systematic literature survey encompassing over 15 000 scientific manuscripts published between 1945 and 2019 reinforces the bias of focusing on studying the targeted effects while overlooking the potential detrimental effects of biorational products on human health and the environment (e.g. death and negative sublethal effects on pollinators and beneficial arthropods such as parasitoids and predators). Thus, the risks associated with biorational compounds (e.g. control failures, the evolution of resistance, shift in dominance, and outbreaks of secondary or primary pests) need to be revisited and the outcomes of such inquiry could be decisive for their future use in pest management programs. The shortcomings of regulatory processes, knowledge gaps, and the outlook for the use of the biorational products in pest management are discussed.

Toxic, Oviposition Deterrent and Oxidative Stress Effects of Thymus vulgaris Essential Oil against Acanthoscelides obtectus

“…Sublethal concentrations of essential oils may also exhibit significant beneficial or detrimental influence on pest life history components, behavior and physiology [30]. For example, we showed beneficial influence of sublethal thyme oil concentration (0.5%) on female survival time.…”

“…On the other hand, drawbacks such as low stability, lower efficacy compared to chemical insecticides and the need for several reapplications can be overcome by improved delivery methods based on nanotechnology [8,10,[27][28][29]. Although the biorationals like EOs are frequently believed to be safe, supposedly because of their natural origin, they can show various negative impacts that need to be investigated and highlighted [30]. Additionally, environmental risks of more toxic and persistent nanopesticides should be examined before their application [28].…”

Essential Oils as Post-Harvest Crop Protectants against the Fruit Fly Drosophila suzukii: Bioactivity and Organoleptic Profile

“…Different plant products, especially essential oils (EOs), are gaining considerable importance. Despite their shortcomings [27], they are bioactive, biodegradable, and ecologically safe [28][29][30]. EOs are complex mixtures of volatile chemical compounds with multiple modes of action [28].…”

Plant-Derived Insecticides Under Meta-Analyses: Status, Biases, and Knowledge Gaps

“…Therefore, concepts, perceptions, and misconceptions should not cloud our understanding of the arguably most influential pest management tools since the onset of the late 1940s broad-scale use of insecticides. So, the neologisms, pleonasms, and misnomers that haunt this subject invite clarification for due understanding [6,8]. Within context, the insecticide paradox deserves attention since the human and environmental concerns with these compounds remain a counterpoint to their increasing worldwide use [7,9,10].…”

“…Another concern is the concept of biorational insecticides, or bioinsecticides for short, which are both associated with perceived advantages likely associated with the suffix "bio". Both are promoted as suitable alternatives to synthetic insecticides in integrated pest management programs [6,8].…”