Coccinellidae as predators of mites: Stethorini in biological control

Abstract

The Stethorini are unique among the Coccinellidae in specializing on mites (principally Tetranychidae) as prey. Consisting of 90 species in two genera, Stethorus and Parasthethorus, the tribe is practically cosmopolitan. The Stethorini are found in a diverse range of habitats, including many agricultural systems such as pome and stone fruits, brambles, tree nuts, citrus, avocadoes, bananas, papaya, palms, tea, cassava, maize, strawberries, vegetables, and cotton, as well as ornamental plantings, grasslands, forests, and heathlands. Tetranychid mite outbreaks became common in many agricultural systems only after World War II, when widespread use of broad-spectrum insecticides increased. Stethorini were initially appreciated only for their ability to suppress severe outbreaks of tetranychid populations. However, research on their prey searching behaviors reveals that Stethorini use visual and olfactory stimuli to locate small mite colonies in patchy distributions, and can be very effective in regulating their prey at low densities. Moreover , acariphagous coccinellids colonize mite outbreaks earlier, and consume more pest mites, than many other mite predators. Key to the use of coccinellids in conservation biological control programs is the provision of overwintering habitats and refuges from pesticides in and near cropland. When these conditions are fulfilled, Stethorini often play important roles in maintaining suppression of tetranychid populations. Examples of successful biological mite control with Stethorini include apple orchards in Pennsylvania, USA, and citrus in Asia, and the unintended disruption of a tetranychid-based biological control program for the invasive woody weed, gorse, in Australia and New Zealand. The systematics and taxonomy of this group is challenging with many cryptic species, and molecular diagnostic tools are sorely needed. How best to utilize their mite-suppressive potential in diverse settings requires better knowledge of their requirements including utilization of alternative foods, refuges for dormancy and from nonselective pesticides , and host-finding mechanisms.

LIFE-HISTORY TRAITS OF Stethorus gilvifrons (MULSANT) (Coleoptera: Coccinellidae) ON PHYTOPHAGOUS MITES Eutetranychus orientalis KLEIN (Acari : Tetranychidae)

“…(Coleoptera: Coccinellidae) is one of the biological control agents of spider mites (Chazeau, 1985;Roy et al, 2003;Roy et al, 2005;Biddinger et al, 2009). In East JavaIndonesia, one species of Stethorus has been observed feeding on spider mites attacking papaya, cassava, mango, apple, and some weeds for around 25 years (Kalshoven, 1981).…”

“…The genus Stethorus comprises a group of ladybird beetle predators belonging to the family of Coccinellidae, under the order of Coleoptera. There are several species under this genus that are used as biological control agents against spider mites (Pollock and Michels, 2007;Biddinger et al, 2009;Roache, 1960). .…”

Interactions between the entomopathogenic fungus Beauveria bassiana and the Neotropical predator Eriopis connexa (Coleoptera: Coccinellidae): Implications in biological control of pest

“…Coccinellidae make up a major group of natural enemies both the larval and adult stages of this predator species feed on different soft-body pests, such as aphids, whiteflies, mites and mealybugs (Biddinger et al 2009;Obrycki et al 2009). Eriopis connexa (Germar) (Coleoptera: Coccinellidae) is a common species in agroecosystems of the Neotropical region where it is considered to be a potential control agent (Sarmento et al 2007;Duarte Gómez and Zenner de Polanía 2009).…”

Comparación de la abundancia y biodiversidad de artrópodos auxiliares entre parcelas de cultivo ecológico y convencional, en plantaciones de cítricos, caqui y nectarina

“…Según Biddinger et al (2009) Los sírfidos se diferencian del resto de depredadores en cuanto a técnicas de muestreo, ya que son capturados mediante trampas adhesivas pero sólo si la posición de éstas es horizontal (Bru y Garcia-Marí, 2008). Sin embargo, el aspirador entomológico, la manga entomológica y el golpeo no son efectivos para muestrear esta familia de depredadores (Wyss, 1996;Alvis, 2003).…”

“…Gráfica de correlación entre la abundancia media por parcela de las diferentes especies de coccinélidos y la proporción de parcelas con presencia de la especie de coccinélido. (Biddinger et al, 2009). Cuando se separan por cultivos se puede observar que esta relación desaparece en el caso de aquellos cultivos que muestran poblaciones bajas de ambos (sobre todo en el caqui), pero se mantiene de forma muy estrecha en el cultivo de la nectarina, en las parcelas en que hay más T.…”