Verticillium wilt of hops in Oregon, caused by Verticillium
dahliae Kleb., was first reported in 1956. Later, V. albo-atrum
Reinke & Berth. was also isolated from infected hop plants, and thus
both species of the fungus were shown to be the causal agents of the
disease in Oregon.
Hop varieties were compared under field and greenhouse conditions
to determine their relative susceptibility to the twospotted spider
mite, Tetranychus urticac Koch. A fertility schedule was prepared
for mites on resistant and susceptible varieties, and tests were conducted
to compare sex ratio, oviposition rate, survival rate, and
developmental rate of...
The hop cyst nematode, Heterodera humuli Filipjev, 1934 was
first reported from Europe in 1894, however, very little is known
with respect to the biology and economic importance of this pest.
Abundant material from Oregon hop yards provided an excellent
opportunity to add additional details concerning the bionomics of this...
A rapid and reliable assay is needed to evaluate hop
resistance to Verticillium wilt caused by Verticillium
dahliae. Assays used in the past are laborious, require
long incubation periods, and usually produce mild symptoms
which are difficult to evaluate and are often not
consistent. A study comparing several methods for...