Toxicity of acaricides to Raoiella indica and their selectivity for its predator, Amblyseius largoensis (Acari: Tenuipalpidae: Phytoseiidae)

Abstract

Raoiella indica Hirst (Acari: Tenuipalpidae) is considered a pest of coconut palm in Asia and the Middle East. This mite was recently introduced in the Americas, where it spread to several countries and expanded its range of hosts, causing heavy losses to coconut and banana production. The phytoseiid mite Amblyseius largoensis (Muma) is one of the predators most often encountered in coconut palms. Because the current prospects for the control of R. indica in the New World indicate the use of acaricides and the management of their natural enemies, the objective of this study was to evaluate the toxicity of selected acaricides to R. indica and the selectivity (i.e., toxicity to the predator relative to toxicity to the prey) for A. largoensis. Assays were performed by the immersion of banana leaf discs in acaricide solutions, followed by the placing of adult females of the pest or predator on the discs. Mortality of the mites was evaluated after 24 h, and the data obtained were subjected to probit analysis. Abamectin, fenpyroximate, milbemectin and spirodiclofen were the products most toxic to R. indica adults, whereas fenpyroximate and spirodiclofen were the most selective for A. largoensis.

Effect ofAmblyseius largoensis(Acari: Phytoseiidae) onRaoiella Indica(Acari: Tenuipalpidae) by Predator Exclusion and Predator Release Techniques

“…However, R. indica populations in the Caribbean and in areas of recent introduction are still causing damage, which suggests that additional mortality factors may be needed to effectively suppress the populations of this invasive pest, especially mortality factors affecting motile stages of R. indica. Assis et al (2013) identified acaricides that are selective for A. largoensis such as fenpyroximate and spirodiclofen, which could be used to integrate chemical and biological control strategies against R. indica. In addition, provision of alternative food sources could increase predator populations resulting in a better potential control of R. indica.…”

Atividade Acaricida De Extrato a Base De Sementes Dos Frutos De Caçari

“…Além disso, não há registro, até o presente momento, de pesticidas (inseticidas) para o controle dessa espécie no Brasil. Somente, ensaios laboratoriais visando avaliação de eficiência de alguns acaricidas já foram realizados e os produtos que apresentaram Revista êxito foram abamectina, fenpiroximato, milbemectina e spirodiclofeno (Assis, Morais e Gondim, 2013).…”

Effects of spirodiclofen on life history traits and population growth of a spider mite predator Oligota flavicornis (Coleoptera: Staphyllinidae) based on the age‐stage two‐sex life table theory

“…Spirodiclofen, a tetronic acid derivative with acaricidal action, is effective against many phytophagous mite species and all developmental stages of mites, including eggs, and has a pronounced residual effect . It has been used for controlling Panonychus citri, Raoiella indica, Tetranychus urticae and Tarsonemus pallidus , P. ulmi and Aculus schlechtendali . However, the use of pesticides can hamper the effectiveness of natural enemies, interfere with their physiology, behavior, and population growth, alter the balance between natural enemies and their prey, lead to ecological backlashes, and disrupt the ecosystem services they provide .…”

“…It has been used for controlling Panonychus citri, Raoiella indica, Tetranychus urticae and Tarsonemus pallidus , P. ulmi and Aculus schlechtendali . However, the use of pesticides can hamper the effectiveness of natural enemies, interfere with their physiology, behavior, and population growth, alter the balance between natural enemies and their prey, lead to ecological backlashes, and disrupt the ecosystem services they provide . Therefore, the conservation and augmentation of natural enemy insects in a pest management system mainly based on pesticides are important strategies to reduce the side effects of acaricides, while improving the efficiency of natural enemies.…”

“…Recent studies have also shown that several predatory mites could be highly compatible with spirodiclofen; however, the adverse consequences that arthropod natural enemies are negatively affected by sublethal spirodiclofen concentrations in different ways, such as physiological events, mortality, longevity and reproduction, parasitism rate and emergence rate and life‐table parameters have also been reported. However, it is not understood comprehensively how spirodiclofen affects the development, survival, fecundity, and population growth of O. flavicornis , which is the primary consideration for the compatibility of natural enemy insects with pesticides.…”