Distribution of the Predatory MiteTyphlodromus pyri(Acari: Phytoseiidae) on Different Apple Cultivars

Abstract

The effect of apple cultivar on the distribution of the predatory mite Typhlodromus pyri was studied in an experimental orchard where spider mites occurred at negligible densities. Seven apple scab-resistant cultivars, showing some differences in their leaf morphology, were considered. In particular, their leaf blade was classified according to four levels of pubescence. The distribution of T. pyri along the shoots was also studied. In the first experimental year the colonization of different cultivars by T. pyri showed definite patterns, sometimes influenced by the occurrence of eriophyids. One year later, T. pyri abundance again showed some differences among cultivars in conditions of prey scarcity. In both years large phytoseiid populations were recorded on the cultivar N.Y. 18491, despite the low eriophyid occurrence, probably because of its highly pubescent leaf undersurfaces. In contrast, Prima and TSR 29T219, characterized by slightly pubescent leaf undersurfaces, supported low phytoseiid densities independently of prey availability.

Influence of leaf trichomes on predatory mite (Typhlodromus pyri) abundance in grape varieties

“…The presence of leaf trichomes appears to play an important role in promoting persistence of some phytoseiid species and therefore may play a crucial role in the success or failure of biological control in perennial crop systems. Indeed, the presence of trichomes for some generalist phytoseiid species is a more important determinant of abundance than mite prey (Duso 1992;Karban et al 1995;Duso et al 2003). Although un-replicated and correlative, our results from the commercial vineyard are consistent with this hypothesis in that we only found signiWcant ERM populations on the one grape cultivar lacking trichomes and this was also the one cultivar where no T. pryi were observed.…”

“…Although un-replicated and correlative, our results from the commercial vineyard are consistent with this hypothesis in that we only found signiWcant ERM populations on the one grape cultivar lacking trichomes and this was also the one cultivar where no T. pryi were observed. A similar pattern was observed in commercial apple orchards for varieties that diVered in trichomes (Downing and Moilliet 1967;Duso et al 2003).…”

The predatory mite Typhlodromus pyri (Acari: Phytoseiidae) as a biocontrol agent of Eriophyes pyri (Acari: Eriophyidae) on pear

“…Bagar et al (2003) states that during one day a single female of T. pyri is able to consume about 230 individuals of eriophyoid mites, and about 18,000 individuals during its whole life. Duso et al (2003) described the intraplant distribution of T. pyri on apple trees of different cultivars. Kabíček (2003) reported the appearance of T. pyri on apple trees in the Czech Republic, Ripka (1998) in Hungary and Croatia, Praslička et al (2009) recorded a high abundance of T. pyri in comparison with that of other mite species in a fruit orchard managed using integrated pest management system (IPM) in Slovakia.…”

“…The predatory mite Typhlodromus pyri Scheuten, 1857 represents one of the most important biocontrol agents of phytophagous mites occurring in orchards and vineyards in many countries of Europe and North America (Helle & Sabelis 1985;Zacharda 1989;McMurtry 1992;Schausberger 1999;Sengonca et al 2003;Duso et al 2003;Sekrecka & Niemczyk 2006;Praslička et al 2009). Bagar et al (2003) states that during one day a single female of T. pyri is able to consume about 230 individuals of eriophyoid mites, and about 18,000 individuals during its whole life.…”

Cohabitation and intraleaf distribution of phytoseiid mites (Acari: Phytoseiidae) on leaves of Corylus avellana

“…Many phytoseiid species often live on leaves of various deciduous tree and shrub species. Pubescence, raised veins, domatia and other structures on the leaf undersurfaces may positively influence the occurrence of some phytoseiid species (Walter 1992;Kreiter et al 2002;Duso et al 2003;Seelmann et al 2007). …”