Biology Reference
In-Depth Information
cabbage, citrus, corn, cranberry, chayote, onion,
potato, squash, strawberry, tomato, and turf
grasses -St. Augustine, Bermuda, and zoysia.
On tomato there is general stunting and formation
of short lateral roots. The stubby effect is appar-
ently caused by a secretion and not just mechan-
ical piercing by the stylet; there is reduced cell
multiplication. The host list is too long for crop
rotation to be practical, and soil fumigation is not
as effective as with some other species. Aspara-
gus and poinsettia are nonhosts, and asparagus
has a nematicidal effect. This nematode and some
other
Trichodorus
species are vectors of tobacco
rattle virus, cause of potato corky ringspot.
Trichodorus obtusus
Cobb's Stubby Root
Nematode
. On Bermuda grass.
Paratrichodorus pachydermus
Seinhorst
Stubby Root Nematode
. On turf and dahlia.
Trichodorus primitivus On azalea.
treatment with the standard fumigants and also
with systemics gives adequate control. Nonhosts
include peanut, pepper, cucumber, and crotalaria.
Tylenchorhynchus
dubius Reported
on
cereals, grasses,
clovers,
also azalea
and
carnation.
Tylenchorhynchus annulatus (formerly
Tylenchorhynchus martini
).
Sugarcane Stylet
Nematode
. On sugarcane, rice, soybean, and
sweetpotato.
Tylenchorhynchus
martini (see
Tylenchorhynchus annulatus
).
Sugarcane Sty-
let Nematode
. On sugarcane, rice, soybean, and
sweet potato.
Tylenchorhynchus maximus On turf.
▶
Tylenchulus
Tylenchulidae. Female sedentary, with elongated
anterior portion entering the root and swollen,
flask-shaped posterior outside the root; well-
developed stylet with large basal knobs; male
remains small, cylindrical; does not feed.
Tylenchulus semipenetrans
Citrus Nematode
.
First noted in California in 1912, now widespread
in citrus regions; important in California and
Florida, present also in Arizona and Texas.
Hosts other than citrus include olive, persimmon,
grape, and lilac. Citrus trees exhibit a slow
decline resulting from reduced root activity.
Symptoms also include twig dieback, chlorosis
and dying of foliage, wilting under moisture
stress, and reduced fruit production. Control mea-
sures include resistant rootstock, and hot-water
treatment of nursery stock, 25 min at 113
For
10 min at 116
F.
Tylenchorhynchus
Belonolaidae. Stylet nematodes, sometimes
called stunt nematodes, primarily ectoparasities,
somewhat migratory, common in roots of nursery
stock and cultivated plants. Male and female
wormlike, 0.6 to 1.7 mm long; stylet variable in
length with well developed knobs; female has
rounded tail, two ovaries; male tail is pointed;
cuticle coarsely annulated.
Tylenchorhynchus brevidus On grasses.
Tylenchorhynchus capitatus Causes stunting
and chlorosis of pepper, bean,
tomato, and
sweetpotato.
Tylenchorhynchus claytoni
Tesselate Stylet
Nematode
. Common and widespread through
southeastern and eastern states. Associated with
and romeda, apple, arborvitae, azalea, bean, blue-
berry, boxwood, broccoli, cherry, cereals, clo-
vers, corn, cranberry, dogwood, forsythia,
grape, grasses, hemlock, holly, lettuce, lilac,
maple, peach, peanut, pepper, pine, potato, rasp-
berry, rhododendron, soybean, strawberry, sweet
potato, tomato, tulip-tree, veronica, willow, and
yew. Azaleas may be severely injured, with
reduced root system, short twigs, leaf chlorosis
and increased susceptibility to winter injury. Soil
Tylenchus
Tylenchidae. This genus, described in 1865, orig-
inally contained most species with stomato-sty-
lets, but many of these have been transferred to
other genera. Those left are common in soil
around plants but apparently not
important
parasites.
