Biology Reference
In-Depth Information
white cheesy pustules on lower surface. Oospores
wintering in host tissue are liberated by decay in
spring. There are no control measures.
Albugo occidentalis
White Rust
of spinach.
After a report from Virginia in 1910, the disease
went unrecorded until 1937, when it appeared in
epidemic form in Texas; it has since been serious
in Oklahoma and Arkansas and has attacked all
commercial varieties tested at the University of
Wisconsin. The white blisters are small, usually
on underside of leaves, sometimes on upper.
Infected leaves become chlorotic, then brown;
the entire crop may be lost.
Albugo platensis
White Rust
, on trailing four
o'clock, common four o'clock, and boerhavia.
Albugo portulacae
White Rust
of portulaca.
Swollen and deformed branches bear white pus-
tules. Shoots tend to become more erect and
spindling.
Albugo tragopogonis
White Rust
of salsify,
also on African daisy, antennaria, artemisia, cen-
taurea, feverfew, matricaria, senecio and sun-
flower. Light yellow areas appear on leaves. The
epidermis, forced into domelike swellings, bursts
to show chalky sori of spores. Foliage may die;
plants are dwarfed. There is no control.
