Free-living mesostigmatic mites in Australia: their roles in biological control and bioindication

Abstract

The taxonomy, biology and ecology of free-living mesostigmatic mites in Australia and their current and potential use in biological control and bioindication is reviewed. Most current research on free-living Mesostigmata in Australia focuses on species with an established role in the biocontrol of crop pests, such as members of the family Phytoseiidae. Three introduced species and at least seven native species of Phytoseiidae are presently used for the control of phytophagous mites in Australia. The introduced phytoseiids are mostly specific to spider mites and have been selected for resistance to some of the common pesticides. Native species provide the advantage of being generalist feeders and are capable of using alternative food in the absence of mite pests. Therefore they can persist more effectively in the environment and contribute to the control of several pests. The reduced and selective use of pesticides, accompanied by scouting services, has allowed the successful control of phytophagous mites by native species in several Australian tree crops, especially grapevine and citrus. In soils, Mesostigmata are extremely abundant, species-rich and play significant ecological roles. They feed on a broad range of invertebrates, including phytophagous pests that spend part or most of their lives on or in the soil or root systems. However, the majority of mesostigmatic mite species are unknown in Australia. Nevertheless, recent research indicates that many species are habitat-specific, and that they may be sensitive to agricultural practices and other land management systems. Mesostigmata have great potential for biological control of pests, and as indicators of soil quality and sustainable agricultural practices. However, the current paucity of research and information on the taxonomy, life-history and ecology of native species in natural and managed landscapes will continue to hinder their use in biological control and as bioindicators.

Pezothrips kellyanus (Thysanoptera: Thripidae), nueva plaga en cítricos; comportamiento de sus poblaciones, muestreo y enemigos naturales

“…The second most abundant species, G. aculeifer, is a well-known predator of various pests such as the worldwide invasive thrips F. occidentalis (Glockemann, 1992;Thoeming and Poehling, 2006). This mite is commercially available and is used successfully in augmentative releases against thrips and other soil-inhabiting pests such as shore flies in greenhouse crops (Beaulieu and Weeks, 2007;van Lenteren, 2012). Other soil predatory mite families captured in our survey, as Bdellidae, Macrochelidae, Rhodacaridae, Ologamasidae and Pachylaelapidae, include commonly encountered soil predators Smiley, 1990, Koehler, 1997;Krantz, 2009;Gerson et al, 2003;Lindquist et al, 2009).…”

“…Finally, another method for increasing the abundance of G. aculeifer during the period when thrips damage occurs might be through augmentative releases. This is greatly facilitated by the fact that this species is commercially available (Beaulieu and Weeks, 2007).…”

“…Common agricultural practices such as the use of pesticides or tillage may affect the soil mite populations and species richness (Koehler, 1997;Beaulieu and Weeks, 2007). According to Baker et al (2011), the run-off of organophosphate sprayings may reduce the population of the soil-dwelling mites, especially potential predators of P. kellyanus.…”

“…Finally, another method for increasing the abundance of G. aculeifer during the period when thrips damage occurs might be through augmentative releases. This is greatly facilitated by the fact that this species is commercially available (Beaulieu and Weeks, 2007).It is also important to highlight the strong, positive relationship between the population abundance and damage caused by P. kellyanus with the abundance of P. americanus. Intraguild predation on G. aculeifer by P. americanus is indirectly supported by the complementary seasonal trend observed for both species (Fig.…”

“…As no effective natural enemies of P. kellyanus were found on the citrus canopy and due to the fact that thrips pupate exclusively in the soil (Jamieson and Stevens, 2006; it is important to study the potential for biological control of P. kellyanus in this stratum. Knowledge about the species of soil-dwelling predatory mites may provide valuable information for the biological control of P. kellyanus and probably other thrips species.Common agricultural practices such as the use of pesticides or tillage may affect the soil mite populations and species richness (Koehler, 1997;Beaulieu and Weeks, 2007). According to Baker et al (2011), the run-off of organophosphate sprayings may reduce the population of the soil-dwelling mites, especially potential predators of P. kellyanus.…”