NEBRASKA
UNIVERSITY OF NEBRASKA AND THE USDA-ARS
Department of Agronomy, Lincoln, NE 68583, USA.
P.S. Baenziger, B. Beecher, D. Baltensperger, L. Nelson, I. Dweikat, M. Dickman, A. Mitra, T. Clemente, S. Sato, J. Watkins, J. Schimelfenig, and G. Hein (University of Nebraska); and R.A. Graybosch, L. Divis, R. French, and D. Stenger (USDA-ARS)
The 2003 Nebraska wheat crop was estimated at 79,900,000 bu, which represented a 47 bu/acre state average yield on 1,700,000 harvested acres. Acres planted to winter wheat in the autumn of 2002 were 1,800,000. The 2003 crop was 64 % larger than the 2002 crop, which was the smallest crop since 1944 and had the lowest yield since 1991. The 2003 crop had the highest yield since 1999 crop (86,400,000 bu from 1,800,000 harvested acres with a 48 bu/acre state average yield, which was a record).
.S. Baenziger, K. Gill, K. Eskridge, Fufa Hundera Birru, I. Dweikat, and A. Mahmood.
This research was undertaken with the expectation as we learn
more about the wheat genome; we would be able to develop better
breeding strategies. The work was in collaboration with Kent
Eskridge, Kulvinder Gill (now the Vogel Chair at Washington State
University), and Ismail Dweikat. In 2003, the research of Fufa
Hundera Birru, a Ph.D. student, and Abid Mahmood, a visiting scientist
from Pakistan, provided new insight into how our cultivars were
bred. Fufa studied the genetic diversity of 30 historical to
modern wheat cultivars and found Cheyenne (CNN, believed to the
founding parent in our germ plasm) was closely related to Wichita.
Both lines would be considered as being important ancestral parents
of many Great Plains wheat cultivars. In previous studies, we
determined that chromosome 3A of Wichita (WI) has very favorable
genes for grain yield and agronomic performance. In preliminary
studies, Dr. Mahmood studied the genetic diversity among chromosome
3A for 48 historic to modern wheat cultivars (including the 30
of Fufa's study) and found that no modern cultivar contained an
intact CNN chromosome 3A , however, some modern cultivars contained
a nearly intact WI chromosome 3A. Furthermore, when three genetic
markers were used to study two previously identified regions containing
favorable genes from WI, the cultivars could be group into those
related to CNN (mainly western wheats where the WI genes had less
value), to WI (mainly high yielding wheats where the genes should
have value), and unrelated to CNN or WI, which we believe indicates
new favorable alleles have been brought into our germ plasm for
those genetic regions.
P.S. Baenziger, T. Clemente, S. Sato, J. Watkins, J. Schimelfenig,
A. Mitra, and M. Dickman.
Wheat transformation continues to be a key strategic effort in
the wheat improvement overall effort. In our current research,
we are emphasizing trying to develop wheat lines with improved
FHB resistance as part of the U.S. Wheat and Barely Scab Initiative.
This study is a collaborative effort between T. Clemente and
S. Sato of the Transformation Core facility (which does our wheat
transformation), J. Watkins and J. Schimelfenig of the Department
of Plant Pathology (who screen conventionally bred and transgenic
wheat lines with FHB), and A. Mitra and M. Dickman, also of the
Department of Plant Pathology, who are studying new concepts in
disease resistance. So far, we have concentrated on transforming
the following genes: a) inhibitors of apoptosis (programmed cell
death) ced9, IAP, and BCL X(L); b) lactoferrin and a related derived
protein, lactoferricin; and c) related antifungal proteins that
have been derived based on similar protein structures. Based
on our greenhouse screening data, it appears that inhibitors of
apoptosis, and lactoferrin and lactoferricin inhibit FHB, which
indicates our concept is sound. We hope to retest the best lines
in the field in 2004. The level of inhibition in our transgenic
lines is generally less than that of Alsen (an elite FHB tolerant
spring wheat with resistance derived from Sumai 3). We have begun
crossing the best transgenes based on our greenhouse screening
results into Alsen to see if we can improve upon the Sumai 3 resistance.
P.S. Baenziger, T. Clemente, S. Sato, J. Watkins, J. Schimelfenig, A. Mitra, and M. Dickman.
In our research to lessen the potential devastating impact of FHB, we are complementing our transgenic wheat research with conventional breeding as part of the National Wheat and Barley Scab Initiative. Each year we are introgressing germplasm lines with FHB tolerance identified by the germ plasm screening efforts of the Initiative into to our best lines. After repeated field testing, we have begun to identify Nebraska adapted lines with better FHB tolerance. These adapted lines will be used as parents in crosses with the germ plasm lines in hopes of increasing the level of tolerance above that of the germ plasm lines or the adapted lines. The adapted lines are:
| ALLIANCE | = ARKAN/COLT//CHISHOLM sib |
| ARAPAHOE | = BRULE/3/PKR4*/AGENT//BELOT198/LCR |
| CULVER | = NE82419 X ARAPAHOE |
| GOODSTREAK | = SD3055/KS88H164//NE89646 (=COLT*2/PATRIZANKA) |
| N97V121 | = N87V106/OK88767 |
| NE00403 | = PRONGHORN/ARLIN//ABILENE |
| NE00544 | = SD89180/KARL 92 |
| NE99579 | = TOMAHAWK/PRONGHORN//NE89657 |
| NIOBRARA | = TAM105*4/AMIGO (TX80GH2679)//BRULE Fsel |
| WESLEY | = KS831936-3//COLT/CODY |
Arapahoe is a parent in many of our modern cultivars and Wesley and Culver are cultivars that are widely grown in the regions that are most likely to have FHB epidemics. Hence, producers can reduce the risk of FHB while growing excellent lines.
P.S. Baenziger.
In 2003, NE95T426 (WB-UW24/TxTcl #50//Fain Tcl/Ctk 78//NE69150/6TA876 / Unknown (probably 6A365/NE69150) was recommended for release and the first commercial foundation seed sales were made. WB-UW24 is a line of unknown pedigree that was sent to the program in the late 1980s as part of an international nursery. NE95T426 will be released at NE426GT and co-released with Iowa State University. The GT designation is in recognition that it can be used either as a autumn and early spring forage triticale (determined by Carlyle Thompson of Kansas State University, Hays, KS whose help and interest in fostering triticale production is invaluable) or as a grain triticale. NE426GT is expected to be mainly used in Nebraska in forage blends with our forage triticales (which are haying or spring forage types), so that the blend will have good autumn and spring forage potential and will have less costly to produce. Excellent collaborations were established with a team of triticale researchers at Iowa State University (the breeder is Jean-Luc Jannink) who are interested in grain triticale to diversify their cropping systems. In Iowa, NE426GT is expected to mainly be used as a grain triticale for animal feed. Although the future is always uncertain, triticale is being given a careful look to determine if it can aid producers. With the retirement of Carlyle Thompson, triticale has lost a great friend and champion.
R.A. Graybosch, P.S. Baenziger, B. Beecher, D. Baltensperger,
L. Nelson
The HWWWs Antelope (NW97S278) and Arrowsmith (NW97S182)
were approved for release, and Foundation seed production is underway.
The following HWWs were advanced to the Nebraska Statewide Small
Grains Variety trial for additional testing: NW99L7068, NW97S412-1,
NW97S139-1, NW98S097, and NW97S218-lt.
R.A. Graybosch and P.S. Baenziger.
PI 617069 (96MD7413-58), PI 617070 (96MD7413-36), and PI 617071 (96MD7110-71) partial waxy (reduced amylose) hard winter wheat germ plasm lines were released by the Agricultural Research Service, United States Department of Agriculture, and the Nebraska Agricultural Experiment Station. These partial waxy wheats carry nonfunctional (null) alleles (Wx-A1b and Wx-B1b) at two of the three hexaploid wheat Wx loci. These loci encode isoforms of the enzyme granule-bound starch synthase (GBSS, EC 2.4.1.21), also known as the waxy protein. Wheats with nonfunctional alleles at two loci are known as double-nulls. Double-null, partial waxy wheats produce endosperm starch with reduced amylose content, relative to that of single-null or wild-type wheats.
L.A. Divis, R. Graybosch, P.S. Baenziger, and G. Hein.
Wheat streak mosaic virus is one of the most important diseases
affecting winter wheat in the western Great Plains of North America.
No known resistance to WSMV exists in the primary gene pool of
wheat. However, a resistance gene known as Wsm1, has been
transferred to wheat from perennial relatives. Nebraska-adapted
wheat lines carrying the gene Wsm1, conditioning resistance
to WSMV, were used in this study. Sister-lines from six genetic
populations were analyzed to compare agronomic and quality characteristics
of resistant and susceptible lines in the absence of the virus,
and under a naturally occurring viral infection. Seed composites
from the same randomly selected lines across uninfected locations
were used for quality analyses. Over all populations, there was
no significant difference in yield, but resistant lines had significantly
higher test weight in the uninfected locations. Within each population,
significant differences in yield were observed only in population
1, whereas significant differences in test weight occurred in
populations 1, 2, 5, and 6. At the infected location, resistant
lines were significantly higher in yield in five of six populations.
Over all populations, susceptible lines were significantly higher
in loaf volume and percent water absorption, while flour protein
content was significantly higher in two populations. The Wsm1
gene is beneficial when the virus is present, and there seems
to be no yield detriment in the absence of the virus.
Mr. Chris Hoagland left his technologist position to join the USDA in Pullman, WA. Mr. Jerry Bohlmann joined the project as a technologist. Mr. Lekgari A. Lekgari joined the project as a graduate student. Dr. Abid Mahmood completed his year as a visiting scientist with Drs. Baenziger and Dweikat to learn molecular biology and returned to Pakistan. Dr. Bakytzhan Anapiyayev and his student, Mr. Daulet Satybaldiyev, from Kazakhstan visited the laboratory of Dr. Dweikat to learn molecular marker skills.