Vinepox mite
Vinepox mite | ||||||||||||
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![]() Vine pox mite, felt galls form, galls on vine leaf (top of leaf) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Colomerus vitis | ||||||||||||
( Pagenstecher , 1857) |
The vines blister mite ( Colomerus vitis , Syn. : Eriophyes vitis ) is a plant galls -forming mites art that monophag on vines ( Vitis vinifera drawn). It is considered a pest in viticulture , but has no particular economic significance in most growing regions.
description
Females of the vinepox mite reach a body length of 160 to 200 micrometers with a diameter of 40 micrometers. They are elongated worm-like, pale yellow colored animals. As is typical for gall mites , the abdomen (opisthosoma) is elongated and soft-skinned, it has numerous (depending on the source about 65 to 90) rings of oval-shaped, small sclerotized platelets called microtubercles. As is typical for gall mites, the front body ( prosoma ) only has two pairs of legs. The front of the blunt triangular back shield of the prosoma has no lobed extension, it is about 40 micrometers wide and 27 micrometers long. It has diagonal longitudinal lines on the top. To determine the exact genus and species, the bristling (chaetotaxia) and the shape of the female mating organs must be examined microscopically.
Gallen
The galls sit on the leaves of the grapevine. Bubble-like or pox-like bulges appear on the top. These are usually green or yellowish green in color, but can also be slightly reddish. On the underside of the leaf there are depressions in the same places, which are covered by a white to brownish colored felt.
Life cycle
The grape pox mite has two larval stages. The larvae of the second stage already reach the size of sexually mature animals, but do not yet have any mating organs. The species reproduces, at least in Europe, predominantly parthenogenetically . The smallpox mite is monophagous on grapevines and has no other host species.
The species has three lines of development, also morphologically distinguishable, with different ways of life, which are called strains. They may be separate, closely related species, but this has not yet been proven with certainty.
- Felt galls stem. This most widespread trunk forms the typical felt galls described above on the vine leaves. The females of this strain hibernate under bud scales, rarely in crevices of the bark at the branch of the two-year-old side shoots. The females become active in spring and then switch to the freshly sprouting leaves, where they induce galls through their suckling activity. The leaves that emerge first are therefore the most severely affected. After the overwintering generation, numerous other generations, up to six in Switzerland, have been identified. The larvae of the first generation produced by the overwintering females need around 25 days to reach sexual maturity, later generations develop a little faster. In late spring and early summer, the mites of the later generations also colonize the leaves of the fresh shoots. From late summer onwards, the animals begin to retreat to the wintering quarters.
- Buds stem. The animals of this strain do not leave the buds, so they also do not develop leaf galls. The females lay eggs directly in the bud, in which the larvae also develop. From unfolding leaves, they crawl to new buds. With increasing density, they work their way inwards from the bud scales and suck directly on the leaf systems inside. The leaves that develop from the buds often show deformed growth. The infestation rate is highest in late summer to early autumn. Basal buds are more affected than the outer ones. Normally, each female lays a new egg a day and development takes about 20 days. In Spain ten to twenty generations were reached each year. The bud strain of the species was reported from South Africa, the Mediterranean region, Chile and California, it does not occur in Germany or Austria.
- Aphid stem. Mites of this shape cause the entire leaf blade to curvature and curl, which curves downwards. The typical felt galls are not formed by this trunk either. The leaves show different hair morphology (trichomes) in the affected regions, and the growth of the infected shoots can also be compressed. With severe infestation, necroses form on the underside of the leaves. The tribe is also reported to Chile, California and South Africa, in Europe from Romania and Hungary.
Economic importance
When fighting powdery mildew with sulfur, the individuals of the felt galls and the leaf curl shape are also automatically combated. While the Filzgallen strain is usually of little economic importance, regional economic damage is reported by the bud strain. In South Africa, control with acaricides is recommended. Since the animals are well protected within the buds and galls, several treatment courses must be carried out.
Individual evidence
- ↑ HH Keifer: Eriophyid Studies XIV. In: Bulletin of the Department of Agriculture, State of California, Series B , 33, No. 1, 1944, pp. 18-38 ( download ).
- ^ MKP Smith Meyer, EA Ueckermann: African Eriophyoidea: The genus Colomerus. Newkirk & Keifer, 1971 (Acari: Eriophyidae). In: Phytophylactica , 22, No. 1, 1990, pp. 15-22 ( download ).
- ↑ Lucia G. Varela, Walter J. Bentley, Larry J. Bettiga: Grape Erineum Mite. Chapter 77 in: Larry J. Bettiga (Ed.): Grape Pest Management. University of California, Division of Agriculture and Natural Resources (UCANR) Publications, third edition 2013, ISBN 978-1-60107-800-1 .
- ↑ C. Duso, E. de Lillo: Grape . Chapter 3.2.5 in: EE Lindquist, J. Bruin, MW Sabelis (Eds.): Eriophyoid Mites: Their Biology, Natural Enemies and Control. (World Crop Pest series vol. 6). Elsevier, 1996, ISBN 978-0-08-053123-6 .
- ^ CA de Klerk: Chemical Control of the Grape Vine Bud Mite, Eriophyes vitis (Pagenstecher). In: South African Journal of Enology and Viticulture , 6, No. 1, 1985, pp. 13-16.
Web links
- Smallpox mite (leaf gall mite) at the grapevine Chamber of Agriculture North Rhine-Westphalia, Münster, plant protection service.