The Rural Voice, 2001-04, Page 64Scrap Book
New sprayer could cut herbicide use
A precision sprayer developed by
University of Guelph researchers
could help reduce herbicide by up to
60 per cent.
Typically weeds grow in patches in
a field but the whole field usually has
to be sprayed to control diverse weed
populations. Prof. Ralph Brown,
School of Engineering, is leading a
team that had designed a new
"precision" sprayer for applying
weed -specific herbicides to different
patches in a field.
"The precision sprayer can benefit
both farmers and the environment,"
says Brown. "It will allow farmers to
apply the correct amount of the proper
chemical only where it's needed, and
it's better for the environment because
unnecessary chemicals won't be used."
More than 80 per cent of the agri-
cultural chemical tonnage used in
Ontario has been attributed to herb-
icides. In 1992, OMAFRA's Food
Systems 2002 project aimed at cutting
herbicide use in half, a goal already
achieved. Brown predicts the new
sprayer can reduce that amount by a
further 50-60 per cent.
To use the new system, the location
of weeds in a field is mapped by
taking aerial photographs of the field
using a digital camera. With these
photos, weed location information can
be transferred to a digital map known
as a geographic information system
(GIS). This GIS map then directs the
sprayer where to spray for weeds
using a grid system with the sprayer
applying herbicides to targeted
squares on the grid. The sprayer uses a
global positioning system to determine
its own location in the field.
Brown says the advantage of the
map approach is that farmers will
know how much herbicide is peeded
before they enter the field, so they
won't end up with any left over. They
can obtain the same crop yield at a
lower input cost.
Brown is now developing a
decision support system for the
sprayer, using "fuzzy logic" (prog-
ramming a machine to think like a
person, in variables, only faster and
repetitively) to enable the precision
sprayer to determine exactly what
herbicides it will spray on weeds
present in the field. This is crucial in
situations where there are several types
of weeds in a patch and one herbicide
or combination of chemicals is more
effective in controlling one type of
weed than another. The sprayer uses a
direct -injection pump that can spray
up to three different chemicals.0
— Source: University of Guelph
Research Magazine
Spices could replace drugs in pig feed
European pork farmers, cut off from using antibiotics in feeds, are turning to
ordinary herbs and spices to improve growth rates.
"The data would suggest there are herbs and spices out there that are equally
as effective," American swine specialist Brian Hardy told the Saskatchewan
Herb and Spice Association. But until feed makers and swine producers find out
how to use natural products correctly they probably won't be too popular in
North America, Hardy said.
"If we don't get into the (science) and we just assume that a pinch of celery
seed, a pinch of garlic and a pinch of this will give us the result, we might be
disappointed." He feels that European feed formulators themselves haven't done
enough research yet.
Cayenne, celery, cinnamon and bay leaves are used to increase feed intake.
Cayenne is also used to treat diarrhea as are oregano and peppermint. Camomile
is used as a sedative. Fenugreek and meadowsweet are used to treat gastric
ulcers. Garlic is widely used as an antibacterial treatment.
Hardy estimated about three quarters of European swine rations now include
herbs and spices since antibiotics were banned as growth promotants.
But until herb and spice treatments can be formulated to be as efficient and
cost effective as antibiotics, few individual North American producers will
probably, want to make the switch, Hardy said.0
—Source: Western Producer
60 THE RURAL VOICE
Soybean coating
can cut fat in
crispy fried foods
An edible soybean -based
coating developed at the
University of Guelph can reduce
the fat content of crispy fried foods
by more than 50 per cent.
An undergraduate research team
led by Prof. Gauri Mittal, School
of Engineering, developed the
coating to help lessen the fat
content of artery -clogging, deep-
fried foods such as doughnuts and
french fries while maintaining their
taste. Canadians get about 40 per
cent of their caloric intake from
fat, but for good health, they
should strive for 30 per cent at
most, says Polly Rankine, a
registered dietician in Guelph.
According to Mittal, soy
coating is affordable — only one
penny per kilogram of coating —
and could be on the market within
a year. It's also available to any
interested industry.
"This is good news for health -
conscious consumers as well as
farmers," Mittal says. "A new use
for soybeans will further develop
the market and enable farmers to
get a better price for their product."
The high fat contents in fried
foods normally results when water
evaporates out of the product and
is replaced by oil used in the frying
process. But the soy -protein
coating developed by Mittal and
his team acts as a barrier to the oil
and reduces absorption.
To develop the ideal coating,
the researchers tested three soy -
protein alternatives — soy -protein
isolates, low-fat soy flour and
protein concentrates — primarily
for their coating properties. A soy
protein isolate (SPI) was chosen
because it was higher in protein
content and had better film -
forming properties than the others.
Researchers wanted to maintain
the taste and texture of the deep-
fried foods even though the fat was
cut.0
— Source: University of Guelph
Research Magazine
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