The Republican journal., 1917-08-23
Safeguard 1918 Bean Crop.


ton bean anthracnose was described and
the fact mentioned that it is usually and
incorrectly called rust in Maine. The
true bean rust is much less common
and less destructive disease in this State.
It was pointed out that bean anthracnose
is not easy to control and prevention
rather than cure is the best way to handle
it. 1t was stated that if the seed planted
is free from all traces Of anthracnose the
disease would not be troublesome; that
some varieties of beans are more resistant
to it than others; that it is best not to
work among the plants when they are
wet with rain or dew and that spraying
beans with bordeaux mixture is recon-
mended, even though there is differences
of opinion as to it's effectiveness.
Climatic conditions all over the State
during the early part of the present grow
ing season were very favorable for the
development of the disease. AS result
it caused much damage to the young
plants and is now appearing as rusty,
brown spots on the developing pods, in
many instances damaging them severely.
What can the bean grower do to prevent
a repetition of these troubles next year,
or to reduce them to minimum?
An effort should be made to secure dis
ease free seed for planting. Certain
standard varieties of beans which are
grown in Maine are susceptible to an
thracnose in varying degrees. Any field
ease is too valuable to be used for food
this year. The entire crop should be
saved and distributed for seed in 1918.
Failing such source of seed supply, go
through the field before harvesting and
pick off sufficient, mature, well-formed
pods, which have entirely escaped at
tack, to furnish the required amount of
seed for next years planting. 1t is not
enough to select seed from the general
crop that appears to be healthy. No mat
ter how carefully beans are picked over
many which are only slightly diseased
will get by and serve as centers of infec-
ton for these young plants. The seed
beans become infected by the fungus
growing into them from the diseased
pods before they are harvested. Hence
if the pods are free from anthracnose the
beans should also be free from it.
Where possible the more resistant va
rieties of beans should be grown. How
ever, for those who will give the matter
the necessary care there are possibilities
ahead for securing resistant strains of
susceptible varieties.
Some IL or Is years ago a grower in
the State of New York found single
plant standing up alone in field of Red
Kidney beans, the only healthy one there.
This strain has been propagated and found
highly resistant to anthracnose.
Even after care has been taken to Sc
lect seed free from disease it would not al
ways be safe to depend on this alone,
especially in a season like the present.
Of course clean seed would be of little
value if planted alongside or near fields
where such care had not been taken with
the seed. At Highmoore Farm, the Maine
Agricultural Experiment Station is carry
ing on an extensive series of bean breed
ing experiments. Here numerous varie-
ties and crosses of different degrees of
susceptibility to the disease must be
grown in close proximity. This year these
beans were sprayed with bordeaux mix
ture soon after they broke ground, and
this treatment has been repeated at fire.
quent intervals. Recently the man in
charge of these bean breeding plots, who
makes a careful examination of and
makes notes on each strain or variety
tested, stated that as a whole they were
never so free from anthracnose at this
time of the year. They were not sprayed
in the past.
In 1913 the plant pathologist of the Sta
ton conducted spraying experiment at
Highmoor Farm for the control of bean
anthracnose. The seed used for planting
came from a field of Improved Yellow
eye beans on which a large amount of
the disease occurred the season before.
Both bordeaux mixture and lime-sulphur
were used. One third of the field was
sprayed with each and the other third
left unsprayed for check
The beans were planted June 18th, and
had all broken ground June 18th. The
first spray applications were made June
21st, these were repeated June 30th, July
9Th and 18th. The spraying was done as
thoroughly as possible. AS far as could
be observed neither bordeaux mixture
nor lime-sulphur in any way injured the
foliage. The former was used the same
strength as for potatoes and the latter the
same as for apples.
Unfortunately the climatic conditions
that season were not particularly favor
able for the development of anthracnose.
Between four and five thousand pods
were examined on each third of the field
previous to harvest. On the check plot
AS per cent OF these were attacked by
anthracnose. Where the sprays were
used it was reduced to O.19 and 0. 10 per