Amarillo, Texas
February 28, 2006
Alterations in irrigation
schedules may be needed when wheat streak mosaic infection is
suspected in winter wheat crops, according to a
Texas Agricultural
Experiment Station researcher in Amarillo.
Drought this winter has prompted more irrigation of wheat than
normal; however, wheat streak mosaic is also being detected,
said Jacob Price, a graduate student and diagnostic technician
for the Experiment Station's plant pathology department.
Wheat streak mosaic, the most common wheat disease in the Texas
Panhandle, is a problem throughout many wheat production areas,
Price said. The disease is spread by the wheat curl mite and
currently no pesticides can control the mite, he said.
In the High Plains, wheat is frequently irrigated and grown for
both grazing and grain production, he said. It is already known
the disease has a negative impact on plant development and
forage yield.
Now Price is trying to get to the "root" of the problem. He
wants to determine what effect the stunted root systems of
infected plants have on their uptake of irrigation water and
whether different levels of irrigation make a difference on the
plants' growth and yields.
"We're trying to determine if it is worth irrigating at all," he
said.
"I hope this research will develop recommendations on irrigation
for infected wheat plants."
Samples are already being submitted this year with the
yellowing, stunted symptoms of wheat streak mosaic to Jacobs.
After making a diagnosis, he sends the information to the Plant
Diagnostic Information System, a wide-scale information system
used by many agricultural centers.
"What I've seen in my experiments so far is it (the disease)
damages root growth," he said. "Once infected, the roots don't
grow anymore. If they don't develop, they can't take up water
efficiently and expensive irrigation water would be wasted."
Producers normally irrigate using the guidance of the Texas High
Plains Evapotransporation network, Price said. The network
collects weather data from various stations and uses it to
estimate the daily water use of a crop.
By determining how much water the infected plants are actually
taking up, he said he hopes to help producers save water and
money and still maintain the best possible yields under the
diseased scenario.
His study is only a year old, but Price intends to replicated it
two more years both in the greenhouse and in the field. The
greenhouse study looks primarily at root mass, while the field
study tests plant production and yield, he said. He is using a
neutron depth moisture gauge to monitor water uptake.
"When it starts warming up and the wheat starts growing, that's
when we'll see more yellowing and we'll get a lot more samples
to test," he said.
"I'm concerned since we've had so much drought and it's so
expensive to irrigate this year," Price said. "Water-use
efficiency is going to be key."
Writer:
Kay Ledbetter |