Drought Puts Critical Corn Pollination Process In Jeopardy
COLUMBIA, MO.
This year’s corn needs rain and needs it
soon. The next couple weeks are critical for
corn pollination, because silk growth and
tassel pollen-shed must be in sync to create
corn kernels. That coordination relies on water.
“Silks are at least 99 percent water, and they
use it as the driving force to elongate from inside
the husk until they emerge outside the
husks, or about 10 inches,” said William
Wiebold, professor of plant sciences in the University
of Missouri College of Agriculture, Food
and Natural Resources. “If the pollen sheds
from the tassel and the silks aren’t there, no
kernels are produced.”
Silk growth is only half of the critical pollination
process. If the pollen does reach the silk, a
tube created by the pollen grain must be able to
grow down the silk to where the kernel will be,
Wiebold said. There has to be enough water to
keep the corn silk wet enough for the pollen
tube to grow through its entire length to reach
the ear.
This coordination process, colloquially called
nick, is so important that if dry, hot conditions
prevent it, you could see a 30-40 percent yield
loss, Wiebold said.
A typical ear will have 12 to 14 rows, each with
35 to 40 potential kernels, he said. Lose just
three kernels per row and that’s a substantial
yield loss.
The lack of rain is having other negative effects
on corn. Normally, corn tasseling occurs when
plants are 7, maybe 8 feet tall, Wiebold said.
Water pushes that growth.
“There are reports coming from throughout
the state that corn is tasseling at 5 1/2 to 6 feet
tall,” Wiebold said. “That’s a couple of feet
shorter than normal, and it’s because there’s
wasn’t enough water to increase plant cell size.”
Corn leaf blades are coming in smaller for the
same reason. All these stresses put this season’s
corn yield in question.
“Probably the next two weeks will really determine
what our yield will be,” Wiebold said.
“Some places that had rain, like northwest Missouri,
will see less yield loss. Places like St.
Charles County and along the rivers, which
have deeper soils with good water-holding capacity,
should also experience less yield loss.”
Places that have seen little rain, have claypan
soils or have compacted soils will experience
large yield losses if rain doesn’t come soon. A
heavy yield hit in the Corn Belt could send ripples
through the futures market.
“The Chicago futures market will start calling
around to the states to see what the weather is
like,” Wiebold said. “It’s really important and it
can drive the market price that farmers will receive.”
Less corn produced would mean higher prices,
putting pressure on livestock producers who
feed corn. At the end of this food chain, consumers
could see sticker shock for meat and
dairy products. Δ