Fargo, North Dakota
October 19, 2006
As interest in growing corn
increases in North Dakota, the
North Dakota State University (NDSU) breeding program
continues to develop new, early maturing inbred lines with above
average drought tolerance.
"NDSU's active corn breeding program, with 15 testing locations
across the state, is essential to support the growth of corn
production," says Marcelo Carena, NDSU's corn breeder. More than
40 institutions (private and public) have requested corn
products developed at North Dakota State University.
In 2006, North Dakota producers planted more than 1.7 million
acres of corn. Interest in selling corn to ethanol plants,
increased disease in small grains and research at NDSU are
contributing to that growth.
"Our corn breeding program is unique in that we have a winter
nursery in Chile in order to have two corn growing seasons per
year," Carena says. "Our location in Chile has the advantage
that drought conditions can be controlled. We know there is no
rain, so irrigation allows us to well manage our trials. The
reason is that it is only possible to screen for drought
tolerance in a location where you can manage the stress and it
is not just the advantage of having an extra generation. The key
to breeding for drought tolerance is to manage the stress. The
objective of these experiments is not to simulate a farmer's
field, but rather simulate a clearly defined stress that is
relevant in farmers' fields. Therefore, if we use the western
part of the state under random stresses, breeding progress for
drought tolerance is not achieved. In Chile, we know of a place
that is dry, never rains, and our cooperator is set up with an
irrigation system that allows us to decide when to stop
irrigating, collect data, select the best lines and hybrids, and
test them in North Dakota the following summer."
Carena screens more than 2,500 inbreds and hybrids in Chile per
year. Varieties that show promise are brought back to North
Dakota for testing at sites across the state. Carena says the
advantage of this system is that it speeds up the development
process in an accurate and efficient way. Only one or two lines
survive after three to five years of vigorous testing drought
tolerance and agronomic performance, including grain yield and
quality.
"Another unique feature of our testing efforts is the fact that
our program is the most northern public breeding program,"
Carena says. "Our program is even north of the two Canadian corn
breeding programs."
A great deal of Carena's work focuses on early maturing corn
because of the state's climate. Early corn has similar genetic
potential as late corn if you have an extensive and accurate
program to identify it.
"For producers who want to sell their corn to a local ethanol
plant, they need an early maturing hybrid with some level of
drought tolerance, above-average quality and standability,"
Carena says. "Our corn breeding program is geared to meeting
those needs so that corn production can remain sustainable in
North Dakota. Our program is one of the unique programs testing
corn hybrids in the western part of the state.
Data are collected for 31 traits, including disease resistance,
maturity, stalk and root lodging, ear quality and seed set.
Researchers also test for
herbicide damage, drought and cold tolerance, and salt
tolerance. NDSU researchers also conduct trials in Canada and
Europe prior to releasing a line. The number of tests and the
variety of locations increase the odds that an inbred line's
weaknesses will be exposed before it is released.
The inbred line is crossed by
commercial and public testers to make hybrids. The hybrids then
are analyzed at various locations for characteristics such as
grain yield, moisture, lodging resistance, dropped ears, test
weight, stand emergence, seedling vigor and grain quality.
"NDSU's corn breeding efforts are complementary to those of the
industry in terms of drought tolerance," Carena says. "However,
drought tolerance is a very complex trait controlled by many
genes, the transgenic approaches used by the industry are
limited to a few genes. If we work on most genes, then NDSU's
drought tolerance efforts do not have any limit on genetic
improvement."
Carena notes that the NDSU corn breeding program has been in
existence for more than 75 years. Carena says continuity is
essential for breeding programs to be successful. Carena is the
third official breeder in the history of NDSU. |