Species composition and seasonal changes of spider mite density on a leguminous plant Pueraria lobata

Abstract

Populations of spider mites were sampled from kudzu vine Pueraria lobata (Willd.) from 1997 to 1999 at two study sites in Ibaraki, central Japan. Of the five spider mite species sampled, Tetranychus pueraricola Ehara and Gotoh was the most abundant (accounting for 75.6-96.9% of mites) in each of the three years. The next most abundant species were T. ludeni Zacher (0.8-19.0%), T. parakanzawai Ehara (1.1-9.7%) and T. piercei McGregor (3.1%), but their density and species richness varied from year to year and from site to site. The populations peaked in June and/or September-October. Predators associated with spider mite populations were phytoseiid mites such as Amblyseius tsugawai Ehara, Phytoseius nipponicus Ehara and Neoseiulus womersleyi (Schicha), Scolothrips takahashii Priesner, Oligota spp., Feltiella spp. and stigmaeid mites such as Agistemus exsertus Gonzalez and A. terminalis (Quayle), which were well synchronized with spider mite density. Overwintered females began to appear and oviposit on some herbaceous weeds growing at the study sites in early April. Spider mites appeared on kudzu vine leaves in early May just after flushing. Most colonies (defined as areas surrounded with silky spider mite threads) had only one species but a small percentage had two or three species.

Species composition of spider mites (Acari: Tetranychidae) on vegetables in Okinawa, southwestern Japan

“…Although this species was clarified to have the potential to use a wide range of plant taxa as hosts (Gotoh et al, 2004), it is associated only with the kudzu vine, Pueraria spp. (Fabaceae), as a wild host plant on both main islands of Japan (Suwa and Gotoh, 2006;Gotoh et al, 2007) and Okinawa Island (Gotoh et al, 1996). Pueraria montana (Lour.)…”

The presence of webbing affects the oviposition rate of two-spotted spider mites, Tetranychus urticae (Acari: Tetranychidae)

“…Takafuji and Kamibayashi 1984;Gotoh 1997;Gotoh et al 2007). They construct a complicated three-dimensional web over the leaf surface of their host plant (Saito 1983).…”

Effects of sucrose on survival and oviposition of the predacious insects Stethorus japonicus (Coleoptera: Coccinellidae), Oligota kashmirica benefica (Coleoptera: Staphylinidae), and Scolothrips takahashii (Thysanoptera: Thripidae)

“…Thus, it may also be possible to conserve these populations by providing sugar resources in and around croplands or orchards (Landis et al, 2000). However, it remains unclear what types of sugar, such as floral and extrafloral nectars and honeydew, these predacious insect species frequently exploit under field conditions because studies on their occurrence have only focused on the synchronization of those of spider mites (Takahashi et al, 2001;Kishimoto, 2002;Gotoh et al, 2007). Thus, studies on the habitats of these predacious insect species, in particular non-crop species, during prey scarcity will be needed for successful conservation in the field.…”

“…As these species are specialized predators of spider mites, their occurrences on plants usually synchronize with those of spider mites (Takahashi et al, 2001;Kishimoto, 2002;Gotoh et al, 2007). In addition, predacious insects migrate between orchard trees and neighboring plants, such as groundcover, weeds, and windbreaks, to exploit abundant spider mites ; however, the spatial distribution of spider mites is patchy, and local populaEffects of sucrose on survival and oviposition of the predacious insects Stethorus japonicus (Coleoptera: Coccinellidae), Oligota kashmirica benefica (Coleoptera: Staphylinidae), and Scolothrips takahashii (Thysanoptera: Thripidae) tions of spider mites are likely to be transient (Sabelis, 1991;Sabelis and Janssen, 1994).…”