The Mitchell capital. (Mitchell, Dakota [S.D.]) 1879-1918, 1914-08-20
DAMAGE DONE
BY RED RUST
PLANT PSYCHOLOGIST AT BROOK.
INGS SAYS WHEAT is HURT
BEFORE THE RUST TURNS
20 BLACK

Br%ookings, S. D.-What kind of
-ust causes the damage to the wheat
erop,-"hlack rust" or ''red rust?
This question has frequently come
'ecently to II. s. Coe, consulting
plant 'pathologist at the State Col
iege and experiment station. The fol-
owing is what he says regarding
rust:
.There r two principal rusts
which attack the wheat; one known
Is orange leaf rust (Puccinia rubige-
'vera) and the other as grass rust
Or "black rust" CPuccinia graminis).
The orange leaf rust occurs prin-
cipally upon the lower surface of the
leaf blades and occasionally on the
'eaf sheaths in small oblong orange
colored pustules. This is known as
red rust stage of this particular
rust. As the grain reaches maturity
the red rust" pustules are replaced
by dark brown to black pustules,
which. constitute another stage of the
same rust, known as the black
-ust" stage. The red rust stage OF
his rust causes some damage al
though not nearly as much as the
red rust stage of the grass or stem
rust (Puccinia g~raminis).
"The other rust Of wheat known
As grass rust, stem rust or black
rust (Pueeinia g%raminis). attacks
principally the leaf sheaths and
stems: During the growing season
this rust makes its appearance in
the form of reddish-brown elongated
pustules This is known as the red
4rtrst stage Of tthfs'rust.''1 sithfs stage
of this rust which is responsible for
the greater part of the loss to wheat
from rust because it is present at
the time the grain is filing, and in
stead of permitting the plant food to
be stored in the grain it is taken .up
by the rust. AS the grain natures
this red rust stage is replaced by the
black rust stage, but this does not
take place until after the great ma
jority of the damage has been done.
We must remember that the rusts
have a very complex life history.
They not only produce different stage
on the same plant. but many of them
also produce Still another stage on
an entirely different plant. The
grass rust or stem rust for instance
has three stages in it's life history;
one upon the barberry, and two upon
wheat.
people are correct in saying that
the damage to wheat has been caused
by the black rust if they mean the
rust upon the leaf sheaths and stems
which has produced both the red and
black stages, but if they mean. that
the damage has been done by the
black rust stage alone, they are
wrong. l am inclined to think that
he majority of people do not con-
slider the red rust stage serious put
feel that the damage will he done
is soon as the black rust stage APP
bears. This is undoubtedly due to
he fact that the red rust has largely
disappeared by harvest time, and
since the black rust is so prevalent
1t appears to me that it would be.
better to call the. rust which alta chs
the stems and s1.eaths, and the IL
which does the greatest part of the
lamage, stem rust, since this would
,void confusion and at the same
ime would be the more appropriate
name. a
I'VE must remember that the
usts of wheat have each a red rust
md a black rust stage and thatithe
,amage, for the most part is done
by the red rust stages and not the
black EAST stages" !,