Effects of sheltered ground habitats on the overwintering potential of the predacious mite Neoseiulus californicus (Acari: Phytoseiidae) in apple orchards on mainland Korea

Abstract

Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is an effective predator of spider mites. In Korea, it is distributed on Jeju Island, but is never found further north on the mainland. Due to poor natural control of spider mites by native predatory mites in mainland orchards, commercialization of the Jeju Island strain of N. californicus on the mainland is currently being considered. We conducted two field experiments in mainland apple orchards during winter 2008 and 2009 to assess the effects of sheltered ground habitats on the overwintering potential of N. californicus. In the first experiment, all of the N. californicus individuals that were experimentally placed on bare ground died within 27 days, whereas 70% of mites sheltered by fallen apple leaves or urethane foam survived for more than 27 days. In the second experiment, individuals were released directly onto the ground, either with or without urethane foam. More individuals were found within urethane foam plots than in plots without foam. Sheltered ground habitats would be an important factor for N. californicus when selecting overwintering sites, and could eventually lead to enhanced winter survival. On the other hand, no live N. californicus individuals were found by the end of the winter in either experiment, which suggests that N. californicus could not successfully overwinter in the study area, even in sheltered ground habitats.

Determination of spider mite abundance in soil of field-grown cucumbers and in plants under predatory mite pressure in invasive infestations using HRM real-time PCR assay

“…In Korea, on the other hand, N . californicus was found to survive exposed to bare soil for no longer than 27 days, and no overwintering of mites occurs despite shelter [ 50 ].…”

Environmental Engineering Approaches toward Sustainable Management of Spider Mites

“…Rosette-forming herbaceous plants offer effective overwintering sites for N. californicus in orchards probably because the underside of leaves provides suitable climatic conditions by decreasing VPD and protecting from UV-B radiation [ 103 ]. Interestingly, nondiapausing adult female of N. californicus survived winter better under fallen leaves or artificial shelters on the ground, where the VPD is lower [ 104 ] and UV-B radiation may be filtered out. The lower VPD and lower dose of UV-B radiation are probably critical to overwintering by phytoseiid mites in the field, as shown in laboratory experiments [ 76 , 85 , 92 , 93 ].…”

Predators and Parasitoids-in-First: From Inundative Releases to Preventative Biological Control in Greenhouse Crops

“…Kawashima et al (2006a) reported laboratory experiments showing that textured urethane foam and polyethylene shading nets were suitable sites for the reproduction of N. californicus. Kawashima and Jung (2011) suggested using urethane foam as ground cover in apple orchards to increase the survival of N. californicus populations during the winter. Loughner et al (2011) mimicked domatia on glabrous beans seedlings and Impatiens plants by adding cotton fiber patches and chopped acrylic yarn fibers and found more A. swirskii on plants provided with pollen and artificial domatia than on plants given solely pollen or fibers.…”