Direct and indirect adverse effects of tomato on the predatory mite Neoseiulus californicus feeding on the spider mite Tetranychus evansi

Abstract

Plants may defend themselves against herbivores via morphological traits, chemical traits, or a combination of both. Herbivores that overcome the defensive mechanisms of a plant tend to specialize on this plant due to enhanced protection from natural enemies. Well‐known examples of plants possessing a suite of defensive mechanisms are found in nightshades (Solanaceae), especially in the tomato genus Lycopersicon. The spider mite Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae) is specialized on solanaceous plants and is an invasive pest of tomato in Europe and Africa. Biological control of T. evansi with currently available natural enemies, such as the predatory mites Phytoseiulus persimilis Athias‐Henriot and Neoseiulus californicus McGregor (both Acari: Phytoseiidae), is unsuccessful, with the underlying mechanisms only vaguely known. We hypothesized that T. evansi is a key pest of tomato because this host plant provides a two‐pronged protection from natural enemies. Direct adverse effects of tomato on predators may arise from morphological traits and/or trichome exudates, whereas indirect effects are prey‐mediated through the accumulation of toxic plant compounds. Using a 2 × 3 factorial design, we assessed and separated direct and indirect effects of tomato on the life history of N. californicus feeding on two strains of T. evansi (reared on bean or tomato) on three substrates (tomato leaf, bean leaf, and an artificial cage). Developmental time and oviposition rate of N. californicus were both directly and indirectly negatively affected by tomato whereas offspring sex ratio and survival of juveniles and adult females were unaffected. The direct and indirect, prey‐mediated adverse effects of tomato on N. californicus with T. evansi prey had similar magnitudes and were additive. We conclude that T. evansi per se is a suitable prey species for N. californicus and discuss the results with respect to the potential use of N. californicus as biological control agent of T. evansi on tomato and other host plants.

Mycorrhiza-induced trophic cascade enhances fitness and population growth of an acarine predator

“…Tetranychus evansi is one tetranychid prey species that dramatically reduces population growth rates of P. persimilis (Escudero and Ferragut 2005). However, T. evansi only seems to be an inferior prey when it feeds on solanaceous plants, suggesting a negative bottom-up cascade caused by toxic host plant compounds (Koller et al 2007). T. urticae feeding on the same host plant species grown at different N fertilization regimes did not change the life history characteristics of P. persimilis (Bjornson and Raworth 2003).…”

Comparative life-history traits of three phytoseiid mites associated with Tetranychus urticae (Acari: Tetranychidae) colonies in clementine orchards in eastern Spain: implications for biological control

“…Prey quality can differ depending on the host plant. For example, it is known that predators may ingest accumulated or transformed harmful plant toxins by feeding on prey (de Moraes and McMurtry 1987;Escudero and Ferragut 2005;Koller et al 2007). Microscopic examination of the females at the end of the experiments revealed that their spermathecae contained spermatophores, hence they had mated.…”

Visual, vibratory, and olfactory cues affect interactions between the red spider mite Tetranychus evansi and its predator Phytoseiulus longipes

“…For example, direct negative effects on the search pattern and residence time of Neoseiulus californicus (McGregor) due to glandular trichomes on S. lycopersicum have been reported (Cédola et al 2001;Kennedy 2003;Simmons and Gurr 2005). Furthermore, an indirect prey mediated effect from tomato has recently been demonstrated on N. californicus, probably due to the sequestration of toxic secondary metabolites from the plant by T. evansi (Koller et al 2007). Several studies undertaken in the past to control T. evansi using Phytoseiulus persimilis (AthiasHenriot) and N. idaeus (Denmark & Muma) have not been promising ).…”