Bushland, Texas
November 27, 2006
Perennial wheat? The possibility
is being looked at by a
Texas Agricultural Experiment Station researcher.
Annual wheat, which is
traditionally grown in the Great Plains, is planted in the fall
and dies after harvest in mid-summer. But Dr. Charlie Rush,
Experiment Station plant pathologist, is testing some perennial
lines of wheat bred in Washington state.
These perennial lines regrow after harvest and may survive for
up to five years, Rush said. And eastern Washington is
climatically similar to the Texas Panhandle, except it has
harsher winters.
"This wheat, if it works here, will start growing back as soon
it rains or is irrigated after harvest," he said. "Right now, we
don't know if it will work in our area or not. But there
definitely could be some applications for it if it does."
The perennial wheat could be used as a ground cover for highly
erodible lands, wildlife habitat and an alternative crop for
Conservation Reserve Program lands, Rush said. However,
primarily he is interested in evaluating use of perennial wheats
in dual purpose grain-grazing cropping systems that are
prevalent in the southwestern Great Plains.
Over the years, different breeders have crossed bread wheat with
wild wheat grass in order to acquire a variety of desirable
traits, such as drought tolerance and resistance to diseases and
insects, Rush said. In making these crosses, some of the
resulting lines inherited the perennial trait.
Perennial wheat programs are already underway in Kansas and
Washington.
But it was work on disease resistance by Dr. Tim Murray,
professor and chair of the plant pathology department, and Dr.
Stephen Jones, wheat breeder, both at Washington State
University, that first gained Rush's interest.
"For perennial wheats to have a place in our dual-purpose
cropping systems, they must have good resistance to disease and
insects," Rush said.
For this reason, his primary concern is determining how the 20
experimental lines will hold up against wheat streak mosaic and
greenbugs, something both Jones and Murray also are researching.
In addition to screening for disease and insect resistance, Rush
is also evaluating the perennial wheat lines for forage quality
and yield, water use efficiency and drought tolerance.
"If they have drought tolerance and natural resistance to
diseases and insects, it opens up real possibilities," he said.
"Producers could save the cost of replanting at the very least.
But it could also allow cattle to graze later in the spring and
earlier in the fall, and still allow farmers to harvest for
grain."
Also, Rush said, producers would be able to avoid the fallow
period that sets fields up for erosion. If the perennial wheat
is rained on or irrigated in July, it is possible that cattle
might be able to start grazing as early as August.
"Since perennial wheats typically yield only 70 percent of the
best bread wheat cultivars, I don't see this as competition for
the grain crop, but primarily as another option on forage," he
said.
Lower yields are the primary reason researchers have not been
very interested in perennial wheats, Rush said. But with
increasing energy costs and environmental concerns, perennial
wheats are worth a new look, especially for the dual-purpose
systems.
In September, Rush planted three replications of 20 lines of
perennial wheat in September, plus seven non-perennial varieties
already in commercial production in the High Plains for
comparison. Additionally, he bordered the plots on one side with
a variety highly susceptible to wheat streak mosaic virus and on
the other side with a highly resistant variety.
"One of the things that could quickly kill this project is if
all the perennials are highly susceptible to wheat streak
mosaic," he said. "We don't want to have that bridge for the
virus and mites to over-summer and threaten the fall wheat crop.
"However, we are confident that some of the lines will be
disease-tolerant, because some of Dr. Murray's preliminary
findings on resistance to wheat streak in Washington state,"
Rush said.
Additional testing for insect and disease resistance will be
conducted in the greenhouse with the perennial lines being
inoculated with wheat streak mosaic virus and tested for
resistance to greenbug and possibly bird cherry oat aphids,
which also vector barley yellow dwarf virus, he said.
All the insect screening will be conducted by Dr. Jerry Michels,
Experiment Station entomologist at Bushland.
"Because this whole research is so brand new, we're limited in
the number of treatments we can do until there's more of this
perennial wheat seed available," Rush said.
Disease screening and forage quality sampling using remote
imaging techniques to measure the biomass, instead of clipping
it, has already started and "we're getting good data," Rush
said.
In the first sampling, some of the perennial wheat lines yielded
roughly the same amount of forage as the bread wheats and also
exhibited good resistance to wheat streak, he said.
"I can hardly wait until our next field day to show our regional
wheat producers these new wheat lines," Rush said.
Writer: Kay Ledbetter |