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Better Pork
October 2016
NUTRITION
C
orn is the number one cereal
crop worldwide with 885.3
million tonnes produced,
according to 2011 figures from the
Food and Agriculture Organization
of the United Nations. Not surpris-
ingly, the United States is the top
producer with 313.9 million tonnes
or 35.5 per cent of global produc-
tion, with Canada ranked 11th at 10.7
million tonnes produced in 2011.
In Canada, corn ranks as the third
most valuable crop behind wheat and
canola. With the majority of corn
being grown in southwestern On-
tario, weather conditions are a huge
concern for any given year’s crop-
ping success. In light of the drought
experienced this summer, industry
stakeholders may be concerned about
the feeding value of the 2016 crop.
The U.S. Corn Belt suffered
drought conditions in 2012, when
temperatures in Iowa were 3.8 C
above average and rainfall was 25 per
cent below normal, making it one
of the driest years on record. That
year in Iowa, July was the hottest
recorded since 1936, with 21 days
hitting daily maximum temperatures
above 32 C. The combination of high
temperatures and low rainfall caused
stress on the corn plant during the
critical phase of cob formation and
milk stages of development, resulting
in reduced yields, decreased kernel
mass, and lower kernel number.
Impact of drought on the corn plant
Depending on the timing, drought can
negatively impact a number of vari-
ables – the number of cobs per plant,
the number of kernels per cob, and/or
the size or weight of the kernels.
Drought can also decrease plant
height and leaf area index. During
times of stress, the plant is able to
mobilize carbohydrate reserves in
the leaves and stalks, and nitrogen
reserves in the leaves, to support
nutrient deposition in the kernels.
With lower yields, the total nitrogen
Drought raises questions about energy value of corn
A recent Iowa State University study provides some answers.
by JANICE MURPHY
Josedbey/Creative RF/Getty Images
Depending on the timing, drought can negatively
impact a number of variables – the number of cobs
per plant, the number of kernels per cob, and/or
the size or weight of the kernels.