Damage to vegetables. Root-knot nematodes
are very damaging to carrots, and are pests of numerous other ornamental
and vegetable crop plants. As the roots are compromised, infested
plants are very susceptible to drought.
Biology. Juveniles penetrate host roots
where they establish a feeding site. As they develop they develop into
females, they cause root swellings (root-knots). The female is usually
pear-shaped, with a fragile white cuticle, and may be up to 2 mm in diameter.
Ecology. Root-Knot nematodes are distributed
Symptoms. In general, localized areas of stunted
plants. Infected carrots are typically forked and malformed. Numerous knots
can be found on the tap root and secondary roots. Strawberry plants
look unhealthy and off-color; roots have large or small galls. Infected
tomato plants are stunted and produce little or no fruit. They wilt conspicuously
in warm weather.
Damage to other crops. Meloidogyne
species are also damaging pests of potato and sugarbeet.
Control. Crop rotation with a non-host such
as corn is effective. For infested home gardens, interplanting or
rotating with marigolds will help to suppress populations. Chemical
control can also be effective.
Links and References. Root-knot
nematode on carrots.