The Golden Nematode Invades New York 
By W. L. Popuam, Assistant Chief, Bureau of Entomology and Plant Quarantine, 
Agricultural Research Administration, U. S. Department of Agriculture 
[With 2 Plates] 
Of the many crop pests of foreign 
origin that have become established 
in the United States the golden nem- 
atode (Heterodera rostochiensis Woll.), 
which attacks the roots of potatoes and 
tomatoes, is potentially one of the 
most damaging, and certainly one 
of the most difficult to combat. 
The golden nematode has _ been 
described as “‘a soil infesting organism, 
eel-like in shape, thin as the finest hair, 
and less than My of an inch long.” 
In heavily infested soil thousands of 
them may attack the roots of a single 
potato or tomato plant. Upon reach- 
ing maturity the males die but the 
females, which have embedded them- 
selves in the outer layer of the rootlets, 
eventually develop into tiny spherical 
cysts which may be seen with the 
unaided eye. These cysts may be 
white, cream, yellow, orange, or 
brown in color, according to age. 
Mature cysts, which are filled with 
eggs, usually become detached from 
the roots of the host plant and remain 
like weed seeds in the soil. When po- 
tatoes or tomatoes (the only known 
hosts) are again planted in the field a 
substance excreted from the roots 
stimulates fully developed larvae to 
hatch from the eggs and a new gener- 
ation of nematode takes up the attack. 
Mature cysts may remain viable in 
the soil for at least 8 years without the 
presence of host plants. 
Effect of Nematode First Observed in 1934 
Just when or how the golden nema- 
tode gained entry to this country is not 
known. It is significant, however, 
that a potato grower near Hicksville, 
Nassau County, Long Island, N.Y., 
first became aware of its presence 
when a certain few spots in his field 
would not produce potatoes profitably 
even when he gave particular attention 
to normal cultural procedures for the 
area. In these spots the vines were 
stunted and off color. When _har- 
vested the potatoes were small, many 
no larger than marbles. This was in 
1934. By 1938 these spots had multi- 
plied both in number and size and, at 
a loss to account for the difficulty, the 
grower arranged for a soil analysis, 
suspecting that a mineral deficiency 
was responsible for his trouble. It 
was not until 1941, after infestation in 
the field had become much more 
general, that the real cause of the 
difficulty was determined to be gold- 
en nematode. During the remainder 
of that season an inspection of adjoin- 
ing fields was made by the New York 
State Department of Agriculture and 
Markets and the Federal Bureau of 
Entomology and Plant Quarantine 
which added some 40 acres to the 
known infested area. 
For the purpose of this discussion it 
will suffice to say that by 1945 the 
infested area had been extended to 
involve 34 properties totaling 1,080 
acres. A year later infestation had 
been confirmed on 2,600 acres in- 
volving 81 properties, and an addi- 
tional 3,000 acres, all in Nassau 
County, were known to have been 
operationally exposed. As of this 
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