Hemicycliophora arenaria Raski,
Hemicycliophora arenaria was described by Raski
extensively researched by Van
Gundy (UC Riverside).
Female and all juvenile stages have sheath; also
sloping stylet knobs.
Males are rare, have degenerate esophagus and no
stylet or sheath.
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:
First reported from the Coachella Valley of California on rough lemon
rootstock (Citrus jambhiri).
in California Nematode Pest Rating System.
Second and third juvenile stages must feed to develop.
Males have no stylet and do not feed.
Feeding Mechanism: stylet is inserted 2-3 cells deep - through and between
cells. Dorsal esophageal gland secretions pass into food cell during 1-2
hour quiescent period; then cell contents are withdrawn over period of 2-6 days
during which there is regular pumping of median
The nematode has a feeding tube similar to Trichodorus
polysaccharide tube) which becomes firmly attached to root, and nematode has to
writhe and twist to detach. Nematodes may appear as a fringe around root
Nurse cells increase in volume, and walls thicken; some cells are
multinucleate. Cells collapse when depleted and are pushed to the surface
by meristem activity, thus providing a continuous supply of new food cells for
Root-tip galls are formed by increase in cell divisions (hyperplasia), giving
rise to enlarged cortex.
Citrus, tomato, beans, celery, squash, pepper, and Tokay grape.
Also Hymenoclea salsola (cheesebush) and coyote melon (Cucurbita
palmata) on virgin desert soil.
crops include "Thompson Seedless" grape, cotton, and
rootstocks include trifoliate orange, sweet orange, sour orange,
and Marsh grapefruit.
Greenhouse tests - 36% growth reduction in citrus and 28% in tomato.
Use trifoliate orange rootstocks in citrus.
bromide applied at rate of 200lb/acre eradicates nematodes to soil
depth of 3 ft.
was used at rate of 2 to 4 gal/acre in 6 inches of water to kill 98.7 to
100% of the nematodes in the top 5 ft. of soil.
Hot water treatment of bare-root trees (10 min. at 46 C.) effective.
Note: In 1992, attempts to find H. arenaria in the Coachella
grapefruit orchard in which Van Gundy worked have been unsuccessful. There
have been annual applications of the nematicide
Nemacur (phenamiphos) to the
Host Plant Resistance, Non-hosts and Crop Rotation alternatives:
Van Gundy, S.D. and S.D. McElroy 1969. Sheath nematode: its biology and
control. Proc. 1st Int. Citrus Symp. 2:985-989.