Experimental and Applied Acarology (1996) 20, 1-22
P. Camporese and C. Duso (1996)
Different colonization patterns of phytophagous and predatory mites (Acari: Tetranychidae, Phytoseiidae) on three grape varieties: a case study
Experimental and Applied Acarology 20 (1), 1-22
Abstract: In a vineyard having three varieties of grape (Merlot, Trebbiano and Garganega) differently colonized by two phytoseiid species, Typhlodromus pyri Scheuten and Amblyseius andersoni (Chant), the dynamics of mite populations were monitored over 5 years (1989-1993) in order to study their colonization, interspecific competition and the control of spider mites, i.e. Panonychus ulmi (Koch). These aspects were also investigated by releasing T. pyri, A. andersoni and Amblyseius aberrans (Oudemans) on some of the above varieties. In most of the experimental years (1989-1992), selective pesticides were used in order to allow a successful release of phytoseiids, in particular A. aberrans. The use of non-selective insecticides was re-established during 1993 in order to test its effect on the new mite communities originating from 1989 onwards. In the first years of the experiments an apparent relationship between grape variety and phytoseiid species was observed: in the control plots, A. andersoni occurred on Merlot where T. pyri was rare, while the latter species was largely dominant over A. andersoni on Trebbiano and Garganega. Panonychus ulmi populations reached moderate levels only on Merlot and in the first part of experiments. The variety-phytoseiid species relationship was temporary as, at the end of experiments, T. pyri was completely dominant on all varieties. This new situation started when prey occurrence and interspecific competition decreased in importance. The moderate success of the T. pyri release on Merlot contrasts with the results of previous experiments. Two factors could be involved in this phenomenon: low interspecific competition by phytoseiids and predation by macropredators. Amblyseius aberrans was able to displace A. andersoni and T. pyri on grape varieties where the two species were more abundant and reached higher population densities on varieties with pubescent leaf undersurfaces. In the first experimental year, spider mite densities were reduced more effectively in A. aberrans release plots than in the control or in T. pyri release plots. One year later, P. ulmi reached lower levels in the release treatments than in the control. Typhlodromus pyri and A. aberrans persisted in conditions of prey scarcity. The high competitivity of A. aberrans over the remaining two phytoseiid species constitutes a major factor in selecting predatory species for inoculative releases in vineyards.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Carlo Duso
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
environment/habitat manipulation
Pest and/or beneficial records:
Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
---|---|---|---|---|
Panonychus ulmi | Grapevine (Vitis) | |||
Typhlodromus pyri (predator) | Panonychus ulmi | Grapevine (Vitis) | ||
Amblyseius andersoni (predator) | ||||
Kampimodromus aberrans (predator) |