Nematodes

picture: canacoll
Latest Update 149th January 2015.

Nematodes
  • Root knot nematodes or eel worms have a bad reputation amongst gardeners.  They are seen as a major pests attacking the roots of edible plants like potatoes, tomatoes and brassicas, seriously effecting yields and often killing the plants.
  • However, they are only one of 20,000 known species of nematode and many of them are beneficial soil borne predators, who feed on other soil microbes (including eel worms) excreting plant nutrients and generally enriching the soil.
  • Most soil borne nematodes are worm shaped and transparent.  They are mostly microscopic in size and multiply quickly.
  • In a farming or gardening context, nematodes are regarded as being predatory (beneficial), pest nematodes (like the eel worm) or vectors, which spread harmful bacteria and viruses amongst crops
In my Garden
  • There are many ways to kill root knot nematodes and other harmful nematodes, but few of them are selective.  Even approved organic method like using a mustard fumigant crop as a green manure will kill beneficial nematodes and other beneficial soil microbes as well as the pest.
  • Crop rotation is an effective defencive measure.  It doesn't allow the pest to get a hold on a crop because the crop is never grown in one bed for more than a year at a time.
  • Generous applications of animal manures and/or compost keep biological activity in the soil at a high level.  This enables the predatory nematodes to prosper and suppress the eel worms.
Information from.
  • Australian Broadcasting Corporation.
  • Picture from canacoll