To study the association between Fusarium root-rot resistance
(Fusarium solani f. sp. phaseoli) and economically inportant characteristics
of beans, 2259 lines each consisting of 30 plants were used.
The lines were randomly selected for root-rot reaction, but were
selected for differences in vigor and differences in plant and seed
pigments,...
Root-knot nematodes were among the earliest plant-parasitic
nematodes to be recognized. Before 1949, they were considered as the
one species Heterodera marioni (Cornu 1887) Goodey 1932. In 1949
Chitwood completed a taxonomic study of the root-knot nematodes and
placed them in a separate genus Meloidogyne. Economically they are
one of...
Laminated root rot of Douglas-fir (Pseudotsuga menziesii (Mirb.)
Franco) caused by the fungus Phellinus weirii (Murr.)Gilbertson was
studied in two successive stands in the Oregon Coast Range. Damage
due to the disease in a 60-year-old second-growth stand was compared
with incidence in the preceding 300-year-old stand on the same site....
Root rot due to Armillariella mellea (Vahl. ex Fr.)
Karst. is unusually severe in ponderosa pine near Glenwood,
Washington. Isolate relations, clonal variability, vegetation
patterns, and climate were examined in relation to
severity of disease in this area.
Ninety-one isolates from 70 infection centers were
examined. Pairings of neighboring isolates...
Progenies of two bean crosses were studied for inheritance of resistance to dry root rot caused by Fusarium solani f. phaseoli. O.S.C. 22 (P. vulgaris) was used in both crosses as the susceptible parent. A Mexican line (P. vulgaris) and a line 2014 of the runner bean (P. coccineus) were...
Two thousand and thirty-nine trees on 213 plots are being monitored yearly for
root disease infection and mortality. Three compartments on the Fernan Ranger
District of the Idaho Panhandle National Forests are the site of the project.
Relationships between factors such as species, aspect, slope, elevation,
habitat type, stand appearance...