A Database for Triticeae and Avena
UNIVERSITY OF MISSOURI
Department of Agronomy, and the USDA-ARS, Curtis Hall, Columbia,
A.L. McKendry, J.P. Gustafson, K. Ross, D.N. Tague, Jessica
Tremain, R.L. Wright, S. Liu, Z. Abate, T. Chikmawati, X. Ma,
A. Mahmoud, Miftahuddin, and M. Rodriguez.
Crop statistics. Missouri's wheat crop was harvested
from 760,000 acres, equal to the 2001 acreage and down from 1,000,000
acres harvested in 2000. Statewide, yields averaged 44 bushels,
down 10 bu/acre from that reported in 2001. Total Missouri production
was 33.4 x 10^6^ bu with the highest regional production being
in the southeast (11.1 x 10^6^ bu).
Winter Wheat Performance Tests. The statewide yield
of SRWW cultivars tested in 2002 was 55.7 bu/acre, down 7.3 bu/acre
from the 2001 test average of 63.0 bu/acre. Statewide yields were
down 15.3 bu/acre from the record high yield (71.0 bu/acre) recorded
in 1997. Average yields across the six test locations ranged from
39.3 bu/acre at Lamar to 75.0 bu/acre at Trenton. Average regional
yields ranged from 41.7 bu/acre in the southwestern region to
58.5 bu/acre in the southeastern region to a high of and 63.2
bu/acre in the northern region of the state.
MO 980725, an experimental line from the university
of Missouri's wheat-breeding program, was the highest yielding
SRWW tested, averaging 64.3 bu/acre statewide. Five proprietary
cultivars, including Excel 400-1 (63.7 bu/acre), MFA Brand 2020
(63.0 bu/acre), Lewis 864 (62.2 bu/acre), MFA Brand 1828 (62.1
bu/acre), and MFA brand 766 (61.5 bu/acre), did not differ significantly
in yield from MO 980725. Two other University of Missouri experimental
lines, MO 980525 (63.3 bu/acre) and MO 960903 (61.0 bu/acre),
rounded out the top yield group. Release of both MO 980725 and
MO 980525 is anticipated. Both of these lines have exceptionally
high levels of scab resistance
Regional test weights varied significantly due to differential
environmental conditions and disease pressures during the 2002
crop season. Statewide, the average test weight was 56.7 lb/bu,
down 1.3 lb/bu from the statewide average of 58.0 lb/bu recorded
in 2001. Location averages ranged from a low of 54.0 lb/bu at
Novelty where disease pressure from FHB was significant, to a
high of 58.6 lb/bu at Columbia. Statewide, VA 98W-593 had the
heaviest test weight (59.5 lb/bu). Roane (59.3 lb/bu) and Lewis
864 (58.9 lb/bu) did not differ significantly from VA 98W-593.
Complete results of the 2002 Missouri Winter Wheat Performance
Tests are available on the WWW under Crop Performance Testing
J.P. Gustafson, K. Ross, T. Chikmawati, J. Layton, X. Ma, A.
Mahmoud, Miftahuddin, and M. Rodriguez.
The genes governing Al tolerance on the 4DL and 4RL arms of
wheat and rye, respectively, have been bracketed by AFLP and SSR
markers using a BAC clone from rice and EST clones from wheat.
Our results indicate that a single Al-tolerance (Alt3) gene controls
Al tolerance in our rye RIL population derived from a cross between
Al-tolerant and AL-sensitive parents. An attempt to construct
a high-resolution map of the gene region was initiated by developing
codominant PCR markers flanking the gene. One simple codominant
PCR marker, SUT1, was developed using primers derived from a rice
BAC end. In addition, an EST approach was used to analyze changes
in gene expression in roots of rye when grown under Al stress.
Two cDNA libraries were constructed (Al ssed and unstressed),
and a total of 1,194 and 774 ESTs were generated, respectively.
In order to understand the mechanisms responsible for Al toxicity
and tolerance in plants, we utilized an EST approach to analyze
changes in gene expression in roots of rye when placed under Al
stress. In this manner, we were able to study the response of
rye roots when placed in Al. Out of all the genes analyzed, we
were able to locate 13 that showed significant levels of increased
expression when grown in toxic levels of Al.
The variability enhancement/germ plasm development program
at Oklahoma State University continued to give priority to transferring
durable leaf rust resistance from CIMMYT spring wheats to winter
wheats adapted to the southern and central Great Plains. An extensive
crossing program with new synthetics and synthetic derivatives
developed by CIMMYT is also in progress. These crosses have multiple
objectives including new sources of leaf rust resistance, improved
kernel size, enhanced stay green characteristics, and improved
biomass and yield potential.
During the 2000-01 cycle, more than 1,800 additional winter
and spring wheat materials were introduced (primarily from CIMMYT)
and cleared through quarantine procedures. These materials are
currently being evaluated for multiple disease resistance and
agronomic performance. The best materials will be utilized as
parents to introduce new genetic variability into the program.
For information regarding this program, contact Art Klatt, Department
of Plant & Soil Sciences, 274 Ag Hall, Stillwater, OK 74078.
A.L. McKendry, D.N. Tague, J.A. Tremain, R.L. Wright, S. Liu,
and Z. Abate.
Germ plasm evaluation. We have hypothesized that germ
plasm from different geographical regions may possess genes for
scab resistance that differ from those currently in use and that
these potentially new sources of resistance may complement those
already in use to improve either effectiveness or the stability
of the scab resistance in breeding programs. Winter wheat germ
plasm research over the past 4 years has resulted in evaluation
of scab resistance (types I and II and kernel quality) for 4,262
winter wheat accessions. Among these accessions, approximately
180 have shown intermediate to good levels of resistance in replicated
testing, however, no accessions with immunity have been observed.
Lines possessing resistance on initial screening followed by two
subsequent generations of verification have been made available
upon request to breeders for incorporation in to breeding programs
In addition to accessions currently housed in the National
Small Grains Collection at Aberdeen, Idaho, researchers worldwide
are actively searching for and combining genes for resistance
into their own breeding materials. Through a collaborative research
agreement with CIMMYT, we are attempting to identify and acquire
sources of resistance in improved genetic backgrounds from scab
researchers globally. Approximately 320 lines have been introduced
into the U.S. through this collaborative effort. Because the putative
scab-resistance genes in many of these lines, are in improved
genetic backgrounds, this germ plasm also may contain resistance
to other important U.S. pathogens (e.g., Septoria spp.,
leaf rust, and BYDV).
Genetics of resistance to Fusarium head blight. Studies
investigating the inheritance of scab resistance in Ernie are
ongoing. A set of populations (F1, reciprocal F1, F2, BC1, and
BC2) from the cross 'Ernie/MO 94-317' (a high-yielding, scab-susceptible
parent) were developed and a replicated six-generation means analysis
experiment currently is being completed. Data will be published
in the autumn of 2003. A QTL associated with scab resistance in
Ernie measured as either disease spread or as the FHB index, are
being identified using AFLP and SSR markers in a set of 300 recombinant
inbred lines developed from the above cross. To date, QTL on 3B
(different region from Sumai 3), 4B, and 5A have been found that
are associated with both FHB index and spread, whereas separate
QTL on 2B and 2D have been linked to FHB index and spread, respectively.
Work continues to construct a fine map of these chromosome regions.
QTL for days-to-flower and for spike length also are being mapped
and interactions among these QTL will be investigated.
Kara Bestgen, who has been with the scab germ plasm program
for the past 4 years, has returned to school. Jessica Tremain,
M.S. University of Missouri, has replaced her in this position.
Gordana Surlan Momorovic is a visiting scientist.