Diversity and abundance of phytoseiid mites on Magnolia hypoleuca Siebold et Zuccarini, a candidate source of natural enemies in natural vegetation

Abstract

The species composition and seasonal dynamics of predatory phytoseiid mites on magnolia, Magnolia hypoleuca, were investigated for 4 y to determine whether M. hypoleuca may act as a source of natural enemies for tetranychid and eriophyid mites on apples. Euseius finlandicus was the most dominant species and formed more than 70% of the mite specimens collected during each year. Amblyseius orientalis was also found consistently as the second dominant species. E. finlandicus was found in low numbers in spring, and its density increased gradually to more than 10 adult females per leaf in autumn. Although the seasonal dynamics of A. orientalis showed some variation depending on the survey years and sites, A. orientalis showed a good predatory ability on Panonychus ulmi, and it developed and reproduced well on this prey in the laboratory.

The succession of phytophagous and phytoseiid species in a newly planted apple orchard without insecticide applications

“…In the fourth year,the seven phytoseiid mite species that occurred in the apple orchard were also observed on wild plants in the vicinity of the apple orchard (Toyoshima and Amano, 2006;Toyoshima et al, 2008). While the rate of migration into orchards has been reported to be dependent upon species present on wild plants, the establishment of mite populations within orchards is not dependent on the surrounding natural vegetation .…”

“…These previous studies also collected 18 species of phytoseiid mites from 18 plant species in the natural vegetation around the apple orchard, and phytophagous mites were scarce (Toyoshima and Amano, 2006;Toyoshima et al, 2008). Since phytoseiid mites have been reported to migrate aerially from uncultivated areas into orchards and vineyards (Hoy, 1982;Tixier et al, 1998;Tixier et al, 2000), it is possible that several species of mites may have migrated from the natural vegetation surrounding the orchard into the orchard itself.…”

“…The dominance of P. ulmi was not explained by the occurrence of those phytoseiid species. This dominance of P. ulmi was considered to be due to the population densities of N. womersleyi were typically being insufficient to suppress the T. urticae populations, and T. vulgaris and A. tsugawai do not predate on T. urticae (Toyoshima, 2003;Toyoshima and Amano, 2006).…”

Seasonal fluctuations in foliar mite populations on Viburnum erosum Thunb. var. punctatum Franch. et Sav. (Adoxaceae) and sympatric shrubs in temperate secondary forests in western Japan

“…As for Phytoseiidae, previous studies conducted in the hedgerows of orchards and natural vegetation have reported that populations were sustained throughout the seasons on some tree species with hairy leaves, and that they showed density peaks in either or both early summer/autumn (Duso et al, 2002;Kreiter et al, 2002;Toyoshima and Amano, 2006). These phenomena are consistent with our observations of VEP and vicinal plants; however, there other factors may affect the seasonal fluctuation of phytoseiids on VEP: density of mite preys, availability of alternative food resources such as pollen or fungi on leaves (Duso et al, 2004), or climate conditions, such as temperature or relative humidity.…”

Diversity and abundance of phytoseiid mites in natural vegetation in the vicinity of apple orchards in Japan

“…In Japan, apple orchards are usually located alongside manmade forests composed of Japanese red pine, larch, and/or cedar trees with various deciduous trees and bushes under their canopy. Although few studies have been conducted on phytoseiid fauna in natural vegetation in Japan (Inoue et al, 1991;Toyoshima and Amano, 2006), several authors overseas have shown that the vegetation surrounding orchards is a rich reservoir of phytoseiid mites (Boller et al, 1988;Tuovinen and Rokx, 1991;Tixier et al, 1998;Duso et al, 2003). Predatory mites in such natural vegetation can move aerially into orchards (Tixier et al, 2000).…”