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Minnesota Crop News > 2001-2008 Archives
November
8, 2004
Soybean
Variety Selection: Looking Beyond Bushels
Lizabeth
Stahl, Regional Extension Educator-Crops, University of Minnesota Extension Service
Many producers are making their seed
buying decisions now to take advantage of early order discounts
as well as to lock in orders of varieties that may be in
limited supply. When selecting a soybean variety to plant
next year, a number of characteristics should be considered
including maturity, yield, disease and pest resistance,
iron cholorosis scores, height, lodging, and quality characteristics.
While all of these traits are important, a few of these
are worth noting.
When determining a disease and pest resistance package
for a field, looking at what has happened in the past will
be the best guide in determining future needs. Although
environmental conditions need to be right for disease symptoms
to be observed, most diseases won’t just “go
away” by the next time you rotate to soybeans. If
white mold has ever been a problem in a field, for example,
consider selecting varieties less susceptible to the disease.
Sclerotia, the survival structure of white mold, can remain
viable in the soil for about seven years in the abscense
of a host plant like soybeans. White mold was more common
this year than in the recent past, in part due to the cool
and wet conditions experienced during soybean flowering.
Proper variety selection is the foundation of a white mold
management plan, as it is with most soybean disease management
plans.
Variety selection plays a major role in management of
another prevalent pest problem, Soybean Cyst Nematode (SCN).
University of Minnesota research demonstrates that growing
SCN resistant varieties is the most effective way to lower
SCN populations and to increase yields compared to growing
non-resistant varieties in SCN infested fields. If you
are in a rotation to help manage SCN, be sure to plant
a different variety than has been planted before in the
field. While it is ideal to rotate the source of SCN resistance,
this is commonly not possible since the vast majority of
varieties available today are from the PI 88788 source.
Rotating SCN resistant varieties as well as planting a
susceptible variety when indicated by your management plan
will help prevent the development of resistance to SCN
varieties in your fields.
Additional traits all soybean growers in Minnesota should
be looking at are protein and oil content. Although soybean
growers produce soybeans, processors pay for oil and protein.
Prices received by soybean producers in Minnesota are lower
than received in most other soybean producing states, in
part due to differences in protein and oil content. Minnesota
and South Dakota Soy Processors, AGP, Cargill, and CHS
Inc. are among processors that currently offer premiums
to producers based on protein and oil content.
In a survey conducted by Iowa State Univeristy on soybean
production from 1986 to 2002, Minnesota soybeans averaged
less than 35% protein and 18.5% oil while areas with the
highest values for these traits averaged over 36% protein
and 18.75% oil. Environmental conditions play a major role
in differences, but genetics are also a factor. The goal
is to select high yielding varieties that are at least
35% protein and 19% oil.
The Minnesota Soybean Production website, http://www.soybeans.umn.edu/home.htm,
includes protein and oil information on all varieties tested
in University of Minnesota State Variety Trials and is
the earliest source of soybean variety trial information.
A list of “Winners” (high yielding and high
protein varieties) from these trials is also published
each year on this website.
In summary, when selecting a soybean variety you should first
select a pool of high yielding varieties that meet your agronomic
needs and then look at the protein and oil content of these
varieties. Consult ind ependent yield trials, such as University
variety trials, to aid in variety selection. Research conducted
by Dale Hicks and Seth Naeve, Extension Specialists with
the University of Minnesota Extension Service , demonstrates
that selecting varieties based on replicated yield trials
averaged over a few locations resulted in higher yields the
following year than using results from just one location.
Using at least three sites to select a high yielding variety
with the appropriate defensive package and quality traits
should help lead to optimal yields and profits.
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