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Everglades Experiment Station Mimeo Report EES65-26 April 1965
NEMATODE CONTROL MUCK :SOIL
J. A. Winchester :.
Nematode control is essential for. optimum production of:most crops even in
muck soils. Root knot nematodes are frequently responsible for yield reductions
of 25 percent or more in celery and sweet corn and they may be equally serious
on other -crops. -. ,"
SNematode sampling. Root knot nematodes may be readily recognized by. the galls
they cause on their hosts. Soil and root. samples must .be examined by a nematolo-
gist in order to determine if any other kinds are .present.though. The best time
to check for nematodes is at the end of a crop season by examining roots in the
field. In anyarea where plants appeared to be stunted dig a few plants. Chances
are that root knot galls:.will be present. If not look for short stubby roots or
lesions along the root. If there is any indication of root injury dig soil from
around a number of plants in the field, mix it in a bucket and put about one pint
in a plastic bag. Seal the bag and keep it cool until you can send it to the ad-
dress you can obtain from your County Agent. Soil samples for nematodes are simi-
lar to those for fertilizer recommendations except that the soil must not dry out
or get warm.
Flooding. This is possibly the most common method of nematode control in
muck soils and it is very satisfactory 'if done properly. Work at-the Everglades
"Station: has shown that cultivation of. flooded rice gave excellent root knot con-
.trol. > Recent work has :shown that an alternate flooding-drying program is superiorr
to constant flooding for this purpose. Under greenhouse conditions 2 weeks of
flooding, 2 weeks drying, and 2 weeks of flooding gave as good root knot control
as 7 months of constant flooding. The soil-must dry out well during the drying
period...If heavy rains occur, the- period must be lengthened.. Occasional deep:
disking should be beneficial during the drying period.-..
Fallowing. This system is good for nematode control but because of its detri-
mental effect on the soil it is: not recommended for south Florida soils.
Cover crops. Crotolaria spectabilis is a good cover crop for nematode control.
It is not a host for root knot nematodes and in the absence of a host many of the
nematodes die. The seed of the crop are toxic to livestock and poultry and the
crop should be disked in before seed develop to avoid animal injury.
is Experiment Station, Belle Glade, Florida,
Crop rotation. Pangolagrass in rotation with other crops will give excellent
root knot control. This grass is toxic to these nematodes and a good stand for a
year and a half in muck soil will usually give good enough nematode control for
at least three years of good crop production.
Chemical control. The only nematocides labeled for vegetables and economical
enough for field:use in muck soil are the dichloropropene type materials DD, Vid-
den D and Telone. These may be applied broadcast or in the row 2 to 3 weeks be-
fore planting most vegetables at rates of 40 to 60 gallons per treated acre.
Celery seed beds are frequently treated with broad spectrum nematocides which
also control weeds, soil borne diseases and soil insects. Those recommended based
on work at the Everglades Station are as follows:
per celery seed bed per acre
The first three should be injected about 8 inches deep with shanks set 8
inches apart. Sprinkle with water to provide a good surface seal after treatment.
Wait 2 to 3 weeks in warm weather to seed. If the soil temperature is below 650
or heavy.rains have occurred.wait at least an additional week to plant until the
nematocide can not be smelled in the soil.
Methyl bromide, Brozone, and Trizone are applied under.a plastic tarp sealed
well around the edges to prevent escape of the gas. Remove the tarp in 48 hours
and wait at least 72 hours longer to seed.