ATLANTA, Ga. - A
U.S. Department of
Agriculture geneticist
reported today that
maysm, a compound
found in small amounts
in corn, has the
potential to retard the
growth and develop
ment of the corn ear
worm, the insect pest
that destroyed 140
million bushels of corn
last year.
Maysin
Speaking at yie
American Society of
'Agronomy meeting
, here, Neil W. Widstrom
with " USDA’s
/ Agricultural Research
Service, said that
“crosses between
certain corns which
yield plants with high
maysm content may
help to provide a basis
for developing hybrids
with levels of maysm
has potential to control corn earworai
that cause reductions in
earworai population.”
"Even though silks of
different corns vary
greatly in tlieir relative
maysin content, some
exceeding others by ten
times or more, the
variability suggests that
selection for increased
levels of this growth
retarding factor can be
expected to be ef
fective,” he said.
However,
cautioned
he
that
estimates ot genetic
variation indicate that
about one-half ot the
existing variation is of a
type not easily utilized
in a system of recurring
selection. "This merely
means,” he added,
“that a simple type of
inheritance does not
appear to be the most
probable type con-
Lancaster Farming, Saturday, December 19,1981-A29
trolling the level ot
maysm in com silks. ”
Widstrom, headquar
tered at the ARS
Southern Gram Insects
Potassium affects alfalfa’s
The potassium is critical to
ent maximum yields of
ATLANTA, Ga.
nutrient ele
Research Laboratory in
'fifton, Ga., worked with
entomologists Billy R.
Wiseman and William
W. McMillian, also of
the laboratory, and
protein content
Western Regional
Research* Center
chemists Carl A. Eiliger
and Anthony C. Waiss,
Jr., of Berkeley, Calif.
alfalfa. An Ohio study
over the past 3 years has
revealed that potassium
deficiency not only
reduces the total yield of
alfalfa, but may also
affect the nutritive
value of the forage.
A. L. Barta, research
agronomist at the Ohio
Agricultural Research
and Development
Center, Wooster,
reported results of his
studies during the an
nual meeting of the
American Society of
Agronomy.
Barta said that his
experiments showed
that potassium affects
the ability of alfalfa
roots to utilize nitrogen
from the air. This has a
direct effect on protein
content, the major
reason alfalfa is such a
valuable feedstuff for
livestock (especially
dairy cattle).
The Ohio studies
showed that potassium
deficiency significantly
reduced both the rate of
regrowth of alfalfa after
harvest and the rate of
nitrogen fixation. It is
believed that the rate of
nitrogen fixation is
limited by the supply of
sugars produced by
photosynthesis in the
leaves and transported
to the nodules on- the
roots.
Barta reported that
potassium appeared to
stimulate the movement
of the sugars produced
in the shoot to the roots
where they are utilized
by Rhizobium bacteria
in the nodules to in
crease nitrogen
fixation. The
stimulation was most
obvious during
regrowth of alfalfa after
cutting.
Barta said the
research emphasized
the importance of
maintaining adequate
levels of potassium in
the soil for high alfalfa
yields. He emphasized
that annual alfalfa
production of 1.0 tons per
acre requires more than
400 pounds of
potassium. Farmers
who depend on alfalfa
for high-protein feed
should make certain soil
fertility is adequate by
testing the soil and
applying potassium and
other elements that may
be in short supply.
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The Classified
Livestock
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Has Beastly
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