Exotic ladybirds for biological control of herbivorous insects – a review

Abstract

Since the late 19th century, exotic ladybirds (Coleoptera: Coccinellidae) have been used extensively for suppressing herbivorous insects of economic importance. In recent decades, the introduction of non-native biological control (BC) agents has been greatly limited due to the awareness of the potential non-target effects of introductions. Nonetheless, recent episodes of biological invasions of economically important pests have raised the need to carefully consider whether the expected benefits of pest control go beyond the possible environmental risks of introduction. To better understand the factors that contributed to successful BC programs, here we review the literature behind classical and augmentative BC using exotic ladybirds. Additionally, by means of case studies, we discuss the BC efficacy of selected exotic species, e.g., Coccinella septempunctata L., Harmonia axyridis (Pallas), and Hippodamia variegata (Goeze), and their position within the communities of predators in the introduced areas of USA, Canada, and Chile. In Europe, much of the research on exotic ladybirds has been conducted on the undesired impact of H. axyridis. Therefore, we summarize the risk assessment data for this species and review the field research investigating the ecological impact on European aphidophagous predators. According to the BIO-CAT database of classical BC programs, 212 ladybird species belonging to 68 genera have been released in about 130 years of BC activity, with 14.6% of introductions having resulted in partial, substantial, or complete control of the target pest. However, because post-release evaluation of establishment and BC success has not always been conducted, this rate could underestimate the successful cases. Among other factors, ladybird establishment and pest suppression mostly depend on (1) intrinsic factors, i.e., high voracity, synchronized predator-prey life cycle, and high dispersal ability, and (2) extrinsic factors, i.e., adaptability to the new environment and landscape composition. This review contributes to improved understanding of ladybirds as exotic BC agents.

Biological control of invasive stink bugs: review of global state and future prospects

“…However, environmental risk assessment of T. japonicus as candidate biocontrol agent, conducted in the USA and in Europe, raised ecological concerns due to the apparent low host specificity of T. japonicus and consequent risk that this species might attack non‐target species in the areas of introduction, including beneficial predatory stink bugs (Hedstrom et al, 2017; Botch & Delfosse, 2018; Haye et al, 2020). Legislative restrictions in Europe and the USA severely limit the introduction of exotic species by focusing on perceived risks for non‐targets rather than the benefits of pest reduction (van Lenteren et al, 2006; Rondoni et al, 2021). Now that the occurrence of T. japonicus has been reported in northern Italy (Sabbatini Peverieri et al, 2018), in early 2020 the Italian government authorized the mass production and release of this parasitoid in Italy, where H. halys has caused the highest economic losses in Europe since its arrival in 2012 (Maistrello et al, 2016, 2018).…”

Interactions Among Native and Non-Native Predatory Coccinellidae Influence Biological Control and Biodiversity

“…Various aspects have been reviewed, including trophic ecology ( Lundgren and Webber 2009 ), invasion ecology ( Roy and Wajnberg 2008 , Brown et al 2017 ), and several syntheses of the role of coccinellids in biological control ( Powell and Pell 2007 , Volkl et al 2007 , Michaud and Harwood 2012 , Michaud 2012 ). During the past three decades, several species of predatory Coccinellidae have spread to new continents ( Franzmann 2002 , Rebolledo et al 2009 , Lombaert et al 2010 , Evans et al 2011 , Soares et al 2018 ), prominently Coccinella septempunctata L. and Harmonia axyridis (Pallas), causing significant ecological effects in their new environments ( Obrycki et al 2000 , Roy et al 2016 , Camacho-Cervantes et al 2017 , Rondoni et al 2020 ). Both species are now distributed widely on most continents ( Poutsma et al 2008 , Brown et al 2011 , Evans et al 2011 , Kajita et al 2012 , Mukwevho et al 2017 , CABI Invasive Species Compendium ( https://www.cabi.org/isc/datasheet/26515 ) ( https://www.cabi.org/isc/datasheet/11733 ).…”

“…In a recent review of the role of non-native lady beetles in the biological control of insect pests, Rondoni et al (2020) presented case studies of C . septempunctata and H .…”

“…axyridis and Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) in South America. In this review, we complement Rondoni et al (2020) , by 1) emphasizing the interactions among H . axyridis and C .…”

Entomophagous insects – an introduction

“…The issue starts with two review articles on biological control. Rondoni et al (2021) review the use of ladybirds (Coleoptera: Coccinellidae) in classical biological control and the associated benefits and environmental risks. The paper also provides several case studies, centered on introduced species such as Coccinella septempunctata L., Harmonia axyridis (Pallas), and Hippodamia variegata (Goeze), and analyzes the data obtained from the BIOCAT database of classical biocontrol programs.…”