C-FAR Project: Processed & Unprocessed Manures Effect on
Crop Yield, Soil & Ground
Paul M. Walker, College of Applied Sci. and Tech., Illinois
State University and Walton Kelly, Ground-Water Geochemist, Illinois
State Water Survey
Regulations regarding field application of liquid swine manure
are becoming more stringent. EPA proposed total maximum daily
loads (TMDL) in surface water (rivers, etc.) could limit the application
of swine manure. Procedures which decrease manures nutrient (element)
content must be identified and evaluated. The effect of applying
manure and inorganic fertilizer on subsurface water must be qualified
and quantified. This multi-year project is designed to compare
the use of raw, unprocessed liquid swine manure, effluent collected
from a solid-liquid separator and traditional inorganic fertilizer
as soil amendments for corn and soybean production, and to evaluate
their effects on subsurface water quality. The objectives are
to: 1) compare plant growth and grain production, 2) evaluate
potential for pathogen transfer from manure to grain, and 3) monitor
subsurface chemical and bacterial water quality beneath treated
Outcomes and Impact
The agronomic results are based on data collected from three
growing seasons. Compared to ground water, the unprocessed swine
slurry and separated effluent had elevated levels of many constituents,
especially NH4-N, phosphate, BOD, Al and Zn. The concentrations
of potentially harmful constituents were clearly lower in the
effluent than in the slurry. In addition, the concentrations of
key fractionates were substantially reduced in the effluent for
year four compared to years 1, 2 and 3.
The effluent applied during year four was separated using a continuous
gravity belt thickener in combination with a polyacrylamide polymer
derived flocculant compared to a static gravity screen-rolled
press separator without polymer in years 1, 2 and 3. Mean concentrations
of coliform were higher in slurry than in separated-aerated effluent.
Microbial concentrations of total and fecal coliforms, and E.
coli were not detected in soybean and corn grain samples. Nitrate
concentrations were significantly elevated in the soil water beneath
the inorganic fertilizer plot and slightly elevated beneath the
effluent and slurry plots. It also appears that C1- concentrations
were elevated in groundwater beneath the effluent and manure plots.
Other constituents that were elevated in the slurry and effluent
(NH4-N, HCO3-, PO43-, B, F-, K, Na, Al, Cr, Cu, Fe, Zn, NVOC,
BOD) were not found in anomalous concentrations in the subsurface
water beneath these plots.
Previous manure applications on the control plot made comparisons
difficult. It appears that the soil water and groundwater were
impacted by these applications, with very high concentrations
of NO3-N and C1-, although not the other constituents listed above.
During this four-year project when no treatment was performed
on this plot, the concentrations of NO3-N and C1- tended to decrease
with time. Although groundwater quality was not significantly
impacted by the slurry and effluent amendments in this study,
the fact that NO3-N and C1- concentrations were elevated in the
wells impacted by previous long-term manure applications indicates
the potential for groundwater quality degradation. However, NO3-N
and C1- were the only two contaminants found in the groundwater;
the metals and other elevated constituents found in the slurry
(and effluent) did not appreciably migrate through the soil and
were thus not good indicators of manure contamination of groundwater
at this site.
For soybean, seed yield was similar for the four treatments.
Since soybean can acquire nitrogen from the atmosphere, this result
was expected. For corn, grain yield of plants supplied with effluent,
inorganic nitrogen fertilizer, or unprocessed slurry tended to
be greater than the control. For corn plants that received an
application of nitrogen (effluent, inorganic nitrogen fertilizer,
or unprocessed slurry), no significant differences in grain yield
were observed. Data needs to be collected over a number of years
to assess seasonal variation and long-term effects of application
to agricultural soils. Data collected thus far suggest that effluent
and slurry can serve as satisfactory nitrogen replacements for
inorganic nitrogen fertilizer.
C-FAR Project: Corn Hybrid & Drying Temperature Effects
on End Use Quality
Kevin Baker, College of Applied Sci. and Tech., Illinois State
S.R. Eckhoff and M.R. Paulsen; Agricultural Engineering Dept.,
University of Illinois
The objectives of this project were: to use a laboratory-scale
dryer to dry corn samples at four drying temperatures and evaluate
hybrids by drying temperature differences in wet milling yield;
and to improve estimates of added value for processing of specialty
corn hybrids, including waxy, high-starch, and hard endosperm
Outcomes and Impact
Fifteen commercial hybrids including three waxy varieties were
used in this study. They were grown on the Agricultural Engineering
Farm at the University of Illinois. They were harvested at three
harvest moistures of about 30, 25, and 14 percent wet basis. The two
higher moisture samples were dried at temperatures of 50, 70,
85 and 100°C, using a convection drier at ISU Bloomington
to a target moisture of about 14 percent wet basis.
Samples harvested at 14 percent were not dried further. Stress cracks
in the samples were measured as an index of the effect of drying
severity. The dried samples were scanned with an Infratec 1229,
that uses near infrared transmittance. Extractable starch yields
were predicted using an equation with an R2 of 0.81, and SECV
of 1.33. The starch was studied for the effects of high drying
temperature on elatinization using a differential scanning calorimeter
(DSC 2920), an electron microscope, and with water activity measurements.
The results indicated that the two harvest moistures were significantly
different, with the 25 percent harvest moisture having higher starch
yields, than the 30 percent corn. Corn dried at temperatures of 50 and
70 o C had significantly higher starch yields than those dried
at 85 and 100°C.
Sprays, Trap Promise to Slash Insecticide Use in America's Corn
Don Comis, (301) 504-1625, firstname.lastname@example.org, Source: ARS
News Service, USDA
While Agricultural Research Service scientists are not about
to satisfy a plant pest's craving for pumpkin by serving pie,
they are only too happy to serve a family recipe to die for. The
ingredients of that recipe, including cucurbitacins and other
chemicals from the pumpkin and gourd or cucurbit family, attract
corn rootworm beetles. One of these ingredients is in three new,
low-insecticide bait sprays and a monitoring trap for the beetles.
These commercial products have emerged from a 6-year joint ARS-
university research and demonstration program in the Corn Belt.
The bait sprays are CideTrak, made by Trece, Inc. Salinas, Calif.;
Invite, made by FFP Agriscience, Inc., of Eustis, Fla.; and SLAM,
made by MicroFlo, of Memphis, Tenn. The trap is the Pherocon Corn
Rootworm Trap, made by Trece.
The trap lures beetles with volatile plant chemicals. It enables
farmers or consultants to make sample counts of the beetles to
decide when the numbers are high enough to warrant spraying with
CideTrak, Invite, or SLAM. The baits are sprayed aerially on corn
leaves where the beetles eat. The sprays form drops containing
cucurbitacins and insecticide. The cucurbitacins cause the beetles
to feed almost exclusively on the drops, so they ingest a lethal
dose of insecticide. CideTrak and SLAM get their cucurbitacins
from wild buffalo gourd root powder, while Invite relies on a
Hawkesbury watermelon juice ingredient.
The actual active insecticidal ingredient in the three sprays
is an ounce or less per acre, which is 95 to 98 percent less than
in conventional sprays. The bitter cucurbitacin doesn't appeal
to other insects, so it is safe for bees and other beneficial
insects. The musky smell released when a cantaloupe is sliced
comes primarily from cucurbitacin.
Relay Intercropping of Soybeans and Wheat
Jim Beuerlein, Agronomist, Ohio State University, (614) 292-9080,
Tony Vyn, Agronomist, Ohio State University, (765) 496-3757, email@example.com
Ohio and Indiana farmers who practice relay intercropping of
soybeans and wheat can choose from an array of wheat varieties
that perform well in wider-row spacing, saving on equipment and
seed costs. Wheat row spacing normally is 7.5 inches wide, said
Jim Beuerlein, Ohio State University agronomist. But in studies
conducted by Beuerlein and Purdue University agronomist Tony Vyn,
certain wheat varieties performed just as well when row spacing
was widened to 15 inches.
About two dozen wheat varieties were analyzed for their performance
in Ohio and Indiana. The purpose of making the rows wider than
normal is for the machinery to get through, so you can get more
light coming down into the canopy to help the soybeans grow,"
Beuerlein said. Beuerlein and Vyn grew wheat varieties in both
7.5- and 15-inch row spacings, and compared yield, test weight
and a variety of agronomic characteristics such as height and
heading date. Beuerlein found that varieties that perform well
in wide rows tend to be either tall by nature or grow tall because
of favorable weather; and exhibit a nonerect growth habit that
compensates for skips in the row or low population.
The research showed that wheat normally grown in 15-inch rows
produces 5 percent to 15 percent less yield than wheat grown in
7.5-inch rows, but the lower yield from wide rows is partially
offset by reduced seed costs, Beuerlein said. "When growing
wheat in 15-inch rows, a farmer only has to use half as much seed
per acre," Beuerlein said. "So, for example, if a 7.5-inch
row has a two-bushel seeding rate, the farmer has saved one bushel
at $12 a bushel for seed. He may lose four bushels of grain in
yield, but at a grain cost of $3 per bushel he can still make
the same profit. One bushel of seed has the same value as four
bushels of grain."Seeding rates are significantly lower in
15-inch rows, Vyn said. He added that plants in the wider rows
appear to be somewhat shorter than wheat in narrower rows.
"We observed that it is important to keep seeding rates
at 850,000 seeds per acre in 15-inch rows," Vyn said. "That's
much less than the traditional seeding rate in 7.5-inch rows of
1.3 million to 1.5 million seeds an acre. "We also found
that wide-row wheat is less likely to lodge even with high nitrogen
fertilizer rates." Wider-row spacing saves on equipment costs,
because fewer seed meter units are necessary on the drill, Beuerlein
said. "Farmers are looking for anything that will reduce
production costs," Beuerlein said.
The relay intercropping process usually involves planting wheat
in October, then interplanting soybeans the following year in
late May or early June. Even earlier soybean planting dates are
possible with polymer-coated seeds that delay soybean emergence.
The OSU-Purdue data indicates both crops in an intercropping system
perform well. "In many ways we are not sacrificing wheat
yields in order to gain the potential of 30-bushel-an-acre relay
soybean yields in areas that are traditionally not suited for
double-crop beans," Vyn said.
Source: Candace Pollock, Associate Editor, OARDC Research
Services, Ohio Agricultural Research, and Development Center,
The Ohio State University, 1680 Madison Ave., Wooster, OH 44691,
(330) 202-3550, firstname.lastname@example.org