These nematodes (eelworms, roundworms, trichinae) are among the most species- and individual-rich animal group in the world, with 20,000 different species. Most are very small, ranging from 0.1 to around one millimetre (the largest species, at over 8 m, lives in the sperm whale placenta). Unlike more highly developed arthropods (such as the earthworm), they have no vessels. Usually there are males and egg-laying females, but occasionally there is also a sexless virgin-breeding (pathenogesis). Four larval moults are undergone until sexual maturity. Feeding takes place through a hollow mouth spine that moves rhythmically while sucking. They live with numerous species in the soil and also feed on bacteria or fungi, which is a positive element in the ecological system of a vineyard soil.
In the 1930s, they were recognised as a pest of the grapevine; until then, phylloxera had been mistakenly assumed. In the vineyard, two groups in particular occur, which are very dangerous for the...
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Markus J. Eser
Weinakademiker und Herausgeber „Der Weinkalender“