WASHINGTON
M.K. Walker-Simmons, L.D. Holappa, E.W. Storlie, S.D. Verhey, and R. Wagner.
Molecular and biochemical regulation of wheat seed germination and dormancy.
We have determined the hydration characteristics of heat-soluble, LEA (late embryogenesis abundant) proteins extracted from wheat embryos (Walters et al. 1997). Our results suggest that the heat-soluble, LEA proteins serve as hydration buffers in seeds.
An oleosin has been cloned from dormant seeds of a wild grass (Bromus secalinus) seed. New structural requirements of ABA (abscisic acid), a plant hormone that is an effective inhibitor of sprouting, have been identified. Biological activities of ABA metabolites as sprouting inhibitors have been determined. A modified form of ABA has been synthesized that is resistant to ABA metabolism. This modified ABA has longer-lasting and more effective biological activity as a sprouting inhibitor in wheat than the natural ABA hormone.
Wheat protein kinases, TaPK3 and PKABA1, have been characterized. TaPK3
is a serine/threonine protein kinase that is up-regulated in greening wheat
seedlings. PKABA1 has been demonstrated to suppress gibberellin-induction
of alpha-amylase in a barley aleurone transient gene expression system.
Cold hardiness.
A crown freezing simulation test (LT50 tests) has been developed that can differentiate cold hardy and nonhardy Pacific Northwest wheat cultivars. LT50 results for the common white winter wheat cultivars correlate well with field survivability ratings (r = 0.81). Results of the LT50 tests show that the most cold hardy Pacific Northwest cultivar is Daws.
We determined effects of the Vrn1-Fr1 interval (chromosome 5AL)
on cold hardiness in wheat. This interval contains a gene(s) that has influenced
vernalization requirements and cold hardiness levels. LT50 tests (lethal
temperature of 50 % of plants) were conducted on wheat NILs that differed
for alleles at the Vrn1-Fr1 interval to determine the effects of
the interval on cold hardiness levels between hardy and nonhardy wheats.
The NILs were derived from five backcrosses between a spring wheat recurrent
parent, Marfed, and two winter wheat donor parents, Suweon 185 and Chugoku
81, hardy and nonhardy, respectively. Results showed that the winter NILs
could tolerate a 4.3°C colder LT50 score than the spring NILs, and that
the 'Suweon 185/6*Marfed' winter NILs could tolerate a 0.5°C colder
LT50 than the 'Chugoku 81/6*Marfed' winter NILs. The Vrn1-Fr1 interval
explained between 71 % and 91 % of the variation for LT50 scores between
these genotypes. The NILs were analyzed with the probe Xwg644 to
confirm linkage with the Vrn1-Fr1 interval. EcoRI-digested DNA of
the winter and spring NIL wheat, probed with Xwg644, showed that
a 9.7 Kb band cosegregated with the winter growth habit.
Meeting Announcement.
The 8th International Symposium on Pre-Harvest Sprouting in Cereals will
take place 26 June, 1998, Detmold, Germany. The organizer is D. Weipert,
Association of Cereal Research, P.O. Box 1354, Detmold D-32703, Germany,
FAX: 49-5231-20505.
Publications.
Abrams SR, Rose PA, Cutler AJ, Balsevich JJ, Lei B, and Walker-Simmons MK. 1997. 8'-Methylene ABA - An effective and persistent analog of abscisic acid. Plant Physiol 114:89-97.
Goldmark PJ, Wiens JD, Verhey SD, and Walker-Simmons MK. 1996. Nucleotide sequence of a cDNA clone for an oleosin from dormant Bromus secalinus seeds (accession no. U72411) (PGR 97-002). Plant Physiol 113:305.
Gomez-Cadenas, A., Verhey, S.D., Zhang, P., Holappa, L.D., Ho, T-H.D., Walker-Simmons, M.K. (1998) Involvement of PKABA1 protein kinase in ABA signal transduction in barley aleurone cells. Plant Physiol 114(S): Abstract.
Holappa LD and Walker-Simmons MK. 1997. The wheat protein kinase gene, TaPK3, of the PKABA1 subfamily is differentially regulated in greening wheat seedlings. Plant Mol Biol 33:935-941.
Rose PA, Lei B, Shaw AC, Walker-Simmons MK, Napper S, Quail JW, and Abrams SR. 1996. Chiral synthesis of (+)-8'-demethyl abscisic acid. Can J Chem 74:1836-1843.
Storlie EW, Allan RE, and Walker-Simmons MK. 1998. Effect of the Vrn1-Fr1 interval on cold hardiness levels in wheat near-isogenic lines. Crop Sci (In press).
Walker-Simmons MK, Holappa LD, Abrams GD, and Abrams SR. 1997. ABA metabolites induce group 3 LEA mRNA and inhibit germination in wheat. Physiol Plant 100:474-480.
Walker-Simmons MK. 1998. Protein kinases in seeds. Seed Sci Res (In press).
Walters C, Ried JL, and Walker-Simmons MK. 1997. Hydration characteristics of the heat soluble proteins from mature wheat embryos. Seed Sci Res 7:125-134.
Walters C, Walker-Simmons MK, and Ried JL. 1997. Heat-soluble proteins extracted from wheat seed embryos have tightly bound sugars and unusual hydration properties. Amer Soc Plant Physiol 114(S):113 Abstract.
Walker-Simmons MK, Abrams GD, Holappa LD, and Abrams SR. 1997. Differential effects of ABA metabolites on ABA-responsive gene expression and germination inhibition. Plant Physiol 114(S):53 Abstract.
Walker-Simmons MK and Suzuki H. 1997. Protein kinases in germinating seeds. Seed Biology and Technology: Applications and Advances Symposium, Ft. Collins, CO, 1315 Aug, 1997 (Abstract).
Walker-Simmons MK. 1998. Protein kinases in seeds. Seed Sci Res (In press).
Personnel changes.
Dr. Blair Waldron, postdoctoral associate, arrived in February, 1997 and
has been working on mapping Fusarium head blight resistance genes. Brady
Carter arrived in June, 1997 and is pursuing an M.S. degree examining the
value and G x E interaction of the microsedimentation test for assessing
end-use properties of club wheat.
Club wheat cultivar development.
Approximately 96,000 hectares were planted to white club wheat in Oregon and Washington in the fall of 1996. Rely continues to be the most widely grown club wheat with more than 56 % of this acreage. Three hundred seventy-four crosses were made in 1997. Parents included elite breeding materials and germplasm for genetic studies. Approximately 17,000 F3-F5 headrows were evaluated based on agronomic phenotype and disease reaction. Two hundred and sixteen of 1,115 F4 lines were selected based on agronomic phenotype, microsedimentation test, grain protein, and kernel hardness. Two hundred forty-four lines were evaluated in yield tests grown at two to nine locations. A total of 389 experimental lines in yield trials and more than 10,000 early generation lines were added to our project from the former Oregon club breeding program based in Pendleton. Germplasms originating from Pendleton and Pullman are being grown at locations in both Oregon and Washington for 1998 harvest. More emphasis is being placed on grain quality prior to preliminary yield testing. During the winter of 1996/97, test weight, grain protein, kernel hardness, and microsedimentation were evaluated on 1,115 lines prior to entry in 1998 yield trials. Almost 40 % of these lines were eliminated from the breeding program, because of quality alone. Three lines were included in Washington statewide yield trials, WA7794 (common), WA7752, and WA7793 (clubs). WA7752 has been released as Coda. Coda combines high end-use quality and yield potential with strawbreaker foot rot resistance. Two club lines [WA7854 (ARS9615) and WA7855 (ARS9623)] were advanced to the Western Regional Performance Nursery, and one soft white common (WA7853, a reselection of WA7794) was advanced to the Washington Extension trials.
The 1997 ARS tall nursery consisted of 41 experimental lines and five check varieties that were evaluated for ability to emerge from deep plantings. Two of these lines, ARS96329 and ARS96342, are believed to contain Rht8. Despite having small seeds, ARS96329 emerged as well as Moro in field tests performed by Dr. W. Schillinger and has outyielded Moro by an average of 10 % at low rainfall sites in 1996 and 1997. ARS96343 and Stephens with its semidwarfing gene removed by backcrossing emerged significantly better than Moro in field tests in 1996 and 1997. Unfortunately, ARS96343 has low yield potential, averaging 5 % less than Moro at low rainfall sites in 1996 and 1997. Additional study is needed to determine if the superior emergence of this line is related to its relatively large seed size.
Results from Dr. T. Murray's lab indicate that one experimental line,
ARS9557, contains both strawbreaker foot rot resistance genes identified
to date, Pch1 and Pch2. This line did not show increased resistance
in inoculated field trials compared to Hyak and Coda, which contain only
Pch1. Other experimental lines will be tested for the presence of
both genes to verify this result in other genetic backgrounds.
Fusarium head blight resistance gene mapping.
A population of 112 F5-derived RILs from the cross 'Sumai 3 (resistant)
/ Stoa (moderately susceptible)' grown in the greenhouse was evaluated for
reaction to inoculation with conidia from F. graminearum. At anthesis,
an average of nine spikes of the same size and maturity in each of three
replications per RIL were inoculated with a 10 µl droplet of F.
graminearum conidial suspension (50,000 conidia/ml) placed directly
into a single spikelet near the center of the head. Extent of disease symptoms
was scored individually as percent blighted area for each inoculated head
at 3 weeks after inoculation. Individual head blight scores were combined
to give plot means for incidence and severity. RFLP mapping was done using
one of six restriction enzymes. Because FHB resistance behaves as a quantitatively
inherited trait, one-way ANOVA, multiple regression, and interval analysis
procedures were used to detect associations between DNA markers and phenotypic
data. The 'Sumai 3/Stoa' population displayed transgressive segregants and
significant variation among RIL for FHB severity. More than 650 low copy
DNA clones were screened for polymorphism between the parents. A total of
298 clones was mapped yielding 350 loci. Twelve genomic regions containing
putative QTL were associated (P < 0.05) with FHB resistance, six derived
from each parent. The discovery of this many regions conditioning FHB resistance
from Stoa was surprising. However, some of these regions likely do not contain
QTL, but are false positives because of the rather liberal significance
threshold and the large number of DNA marker associations tested. Four markers,
two from each parent, were associated with resistance at P < 0.01 and
are more likely to represent QTL that will be relevant in other populations.
The best single marker was revealed by the clone Xbcd907 and explained
15.8 % (P < 0.001) of the phenotypic variation. Because of this clone's
complex banding pattern and only one other marker (from clone Xabc483)
in the linkage group of interest, we have been unable to conclusively determine
the chromosomal location of this QTL. A multiple regression model consisting
of one marker from 7 of the 12 significant regions explained 41 % of the
variation for FHB resistance in this population. We are in the process of
verifying these markers in a second population of RIL from the cross of
'ND2603 (Sumai 3/Wheaton)/Butte 86'. In addition, we have initiated AFLP
mapping to identify additional QTLs and strengthen existing marker-QTL linkages.
Publications.
Chee PW, Elias EM, Anderson JA, and Kianian SF. 1997. High protein gene mapping in durum wheat. Agron Abstr p. 76.
Elias EM, Chee PW, Kianian SF, and Anderson JA. 1997. Genetic diversity in durum wheat using RFLP markers. Agron Abstr p. 148.
Faris JD, Anderson JA, Francl LJ, and Jordahl JG. 1997. RFLP mapping of tan spot resistance genes in wheat. In: Progress in genome mapping of wheat and related species: Joint proceedings of the 5th and 6th public workshops of the International Triticeae Mapping Initiative (McGuire PE and Qualset CO eds). 1-3 September, 1995, Norwich, UK; and 30-31 August, 1996, Sydney Australia. Report No. 18. University of California Genetic Resources Conservation Program, Davis CA USA.
Faris JD, Anderson JA, Francl LJ, and Jordahl JG. 1997. RFLP mapping of resistance to chlorosis induction by Pyrenophora tritici-repentis in wheat. Theor Appl Genet 94: 98-103.
Moreno-Sevilla B, Anderson JA, Stack RW, and Frohberg RC. 1997. RFLP mapping of Fusarium head blight in wheat. PAGV, San Diego, CA. p. 96.
Sorrells ME and Anderson JA. 1997. Homoeologous group 3. In: Progress in genome mapping of wheat and related species: Joint proceedings of the 5th and 6th public workshops of the International Triticeae Mapping Initiative (McGuire PE and Qualset CO eds). 1-3 September, 1995, Norwich, UK; and 30-31 August, 1996, Sydney Australia. Report No. 18. University of California Genetic Resources Conservation Program, Davis CA USA.
Udall JA, Souza E, Anderson JA, and Sorrells ME. 1997. Important alleles for noodle quality in winter wheat as identified by molecular markers. PAGV, San Diego, CA. p. 97.
Waldron BL, Anderson JA, Stack RW, Frohberg RC, and Moreno Sevilla B.
1997. Verification of quantitative trait loci for Fusarium head blight resistance
in wheat. Agron Abstr p. 82.
Predicting club wheat quality using Glu1 subunits.
R.E. Allan.
The relationships between soft white club wheat quality criteria and
HMW-glutenin (Glu1A, 1B, 1D) subunit genotypes were
determined among 100 breeding lines. The lines had no prior selection for
quality. They had been selected for agronomic and disease attributes. Quality
measurements were made on samples grown at three locations in four crop
years (1991 to 1994). Quality traits that assess baking and flour quality
were included. They were mixogram dough strength, mixo-absorption, cookie
diameter, top grain score, grain hardness, flour protein content, and viscosity.
These tests were conducted by the ARS Western Wheat Quality Lab. Data for
each trait were analyzed, and the lines were assigned to three performance
groups. Two groups comprised lines falling within the highest and the lowest
groups based on the 5 % LSD; the remaining lines were designated as the
mid group. Determination of the HMW Glu1 subunits was performed by
the lab of S. Jones at Washington State University. The 100 lines comprised
15 different subunit genotypes. Genotypes that occurred in the greatest
frequency were: N 6 212 (37 lines), N 78 212 (19 lines), N 78 510 (8 lines),
2 6 212 (7 lines), N 6 510 (3 lines), and N 7 212, 2 6 510, 2 7 510, 2 78
510 (5 lines each). Six other subunit genotypes each occurred once. N 6
212 subunit combination has been suggested to be the critical genotype relating
to traditional club wheat quality (Rayfuse and Jones, 1993, Plt. Breeding
111:89-98). This hypothesis proved valid for mixogram dough strength,
mixo-absorption, flour viscosity, and cookie diameter. Lines with the N
6 212 genotype versus other genotypes were compared as to their numbers
assigned to each of the three performance groups. The N 6 212 genotype was
associated closely with desirable weak dough strength. None of the N 6 212
lines had undesirably strong dough strength, and 95 % ranked desirable.
Only 14 % of lines with genotypes other than N 6 212 had desirable club
wheat dough strength, whereas nearly 50 % of these lines had undesirable
dough strength. The N 6 212 genotype also was associated strongly with desired
low viscosity. Nearly 70 % of the lines classified good, and only 3 % were
poor; 46 % of the other genotypes had high (poor) viscosities. A preponderance
of N 6 212 lines also had desirably low absorption (70 %) and large cookie
diameter (49 %). Among the other subunit genotypes only 30 % and 25 % had
desirable absorption and cookie diameter, respectively. Subunit genotype
was not useful for predicting top grain score or flour protein content.
The N 6 212 genotype had fewer lines (10 %) with undesirable hard kernel
texture than lines with other subunit genotypes (38 %). These results validate
using HMW-glutenin subunit patterns for predicting flour quality of club
wheat breeding lines.
Publications.
Haro ES and Allan RE. 1997. Effects of heading date on agronomic performance
of winter wheat isolines. Crop Sci 37:346-351.
Allan RE. 1997. Registration of 10 pairs of alloplasmic and euplasmic Stephens wheat germplasms. Crop Sci 37:1033-1034.
Control of rusts and smuts in the western United States, 1997.
Roland F. Line and Xianming Chen.
Using predictive models and monitoring data, stripe rust and leaf rust of wheat were forecasted accurately for the 19th and 15th consecutive year, respectively. Stem rust was forecasted accurately based on weather in June and July. Stripe rust continues to be the most widely important wheat disease in the western U.S. Leaf rust is the second most widely important disease. In northwestern Washington, stripe rust and leaf rust were severe in fields of fall-sown susceptible wheat cultivars. The autumn, winter, and spring environments were highly favorable for establishment, survival, and increase of the rusts. When not controlled, the rusts reduced yields of susceptible cultivars by more than 50 %. In eastern Washington and northern Idaho, relatively wet weather during the fall of 1996, warm temperatures during the winter of 1996-97, and cool wet weather in April were favorable for establishment, survival, and increase of stripe rust and leaf rust. However, relatively dry weather in May and June prevented development of epidemics of leaf rust and severe epidemics of stripe rust. Wetter than normal weather in July provided conditions that were favorable for development of stem rust in late-maturing fields of winter wheat and spring wheat in the Palouse region of Washington and northern Idaho. In California, the winter and spring weather was favorable for stripe rust, and susceptible wheat and barley cultivars were damaged by the disease. The autumn weather in 1997 and the winter weather in 1997-98 were highly favorable for the establishment and survival of both stripe rust and leaf rust in the western U.S. If the early spring is cool and wet, severe stripe rust in the western United States is probable in 1998. If the later spring is wet, leaf rust could be severe in the western United States.
Losses caused by naturally occurring stripe rust, leaf rust, stem rust, powdery mildew, and septoria in 32 winter wheat cultivars at a site near Walla Walla, WA, and two sites near Pullman, WA, and 20 spring wheat cultivars at two sites near Pullman were determined by comparing nontreated plots with plots sprayed with the fungicide Folicur to control the diseases. Losses caused by stripe rust in the plots ranged from 0 % to more than 20 % depending upon the resistance of the cultivars to local races of the pathogens and the weather at each of the sites. Stripe rust caused greater losses at Pullman than at Walla Walla. Leaf rust caused only minimal losses at all sites. Stem rust caused significant losses in late-maturing cultivars, such as Eltan winter wheat and Walladay spring wheat. Powdery mildew and septoria caused no significant losses.
Stripe rust, leaf rust, stem rust, and other wheat diseases are monitored annually to determine their distribution, prevalence, and severity and to determine the vulnerability of cultivars to local races of the pathogens. Barley stripe rust, which was introduced into North America from Europe by way of South America and Mexico in 1991, has spread north and west from Texas. The disease, now indigenous in the western U.S., has significantly impacted barley yields in Colorado, Arizona, Utah, California, Oregon, and Washington. We have determined clearly by pathogenicity and RAPD analysis that the wheat stripe rust pathogen is different from the barley and grass stripe rust pathogens. The wheat stripe rust pathogen, which attacks primarily wheat and triticale, can attack some barley and rye cultivars, and the barley stripe rust pathogen, which attacks primarily barley, can attack some wheat, triticale, and rye cultivars. The bluegrass and orchard grass pathogens are not pathogenic on wheat, barley, triticale, or rye. At least 59 wheat stripe rust races and 50 barley stripe rust races have been detected in North America. In 1997, the most prevalent wheat stripe rust races were those that are virulent on Moro, Tres, Hatton, Weston, Lee, Fielder, Express, and a new line that was being considered for release in California; on seedlings of Stephens and Madsen; and on susceptible cultivars developed in other regions of the U.S. where stripe rust does not normally occur. We detected no new, more virulent races of the leaf rust and stem rust pathogens in the western U.S. in 1997. Powdery mildew, common bunt, flag smut, and dwarf bunt each caused losses in the western U.S. that were less than 0.1 %. Karnal bunt, which is now present in some regions of the U.S., has had an impact on marketing wheat, but current evidence indicates that it has not reduced wheat yields or affected the quality of flour in the U.S.
Each year, we evaluate a new group of entries from the National Small Grain Germplasm Collection for high-temperature, adult-plant resistance to stripe rust in field plots at Mount Vernon and Pullman, WA, and for seedling resistance to selected stripe rust races that include all of the virulences that have been identified in North America. This information is added to their database. Cultivars and breeding lines developed in the western United States also are evaluated annually for resistance to stripe rust and other diseases. Currently, all of the major SWWW and spring wheat cultivars grown in the western U.S. have high-temperature, adult-plant (HTAP) resistance, and their resistance has remained durable against all North American races of stripe rust. New cultivars with superior stripe rust resistance were released, and additional information on stripe rust resistance genes was determined. High-temperature, adult-plant resistance continues to be the most durable resistance to wheat stripe rust. In regions where stripe rust occurs, HTAP resistance has annually prevented severe losses. Multiline cultivars developed in the northwestern United States for stripe rust resistance also have been remained durable.
Molecular markers associated with genes for race-specific, seedling resistance and for HTAP resistance have been located using several techniques. Individual genes for HTAP resistance are harder to identify and transfer into new cultivars; therefore, use of markers associated with HTAP resistance genes is more important. A new technique based on high- resolution electrophoresis was developed for detecting molecular markers associated with resistance genes and was used to determine relationships among wheat, barley, and rice cultivars. The technique also was used for detecting markers associated with race specific, seedling resistance genes and HTAP resistance genes.
Seed treatments and foliar fungicides are evaluated annually for control of stripe rust, leaf rust, stem rust, common bunt, flag smut, dwarf bunt, and other diseases. Treatment of seed with Baytan is now part of the integrated rust control program in the Pacific Northwest. Treatment or seed with Dividend is being used to control dwarf bunt as well as other smuts, and Raxil is now registered for use in the U.S. In 1997, seed treatments and foliar fungicides were evaluated for control of stripe rust, leaf rust, and stem rust in winter wheat and spring wheat plots at sites near Walla Walla and Mt Vernon, WA, and at three sites near Pullman, WA. Treatment of seed with Baytan or Proseed prevented the increase of stripe rust during early plant growth stages in both winter wheat and spring wheat plots. The seed treatments usually were more effective when used in combination with foliar treatments. Foliar applications of Bayleton, Tilt, Folicur, Quadris, or Govern controlled stripe rust, leaf rust, and stem rust when used at various rates and according to various schedules. The effectiveness of the applications at specific schedules depended upon the type of rust, susceptibility of the cultivars to the specific types of rust, the stage of plant growth when the fungicides were applied, and the local weather. Applications before rust severity developed to 20 % were most effective.
A computerized, expert system called MoreCrop (Managerial Options for Reasonable Economical Control of Rusts and Other Pathogens) was developed in 1993 for predicting and managing wheat diseases in the Pacific Northwest of the United States. MoreCrop predicts diseases and provides information, options, and suggestions to help the user make decisions regarding management of wheat diseases. Diseases are predicted based on geographical regions, agronomic zones, crop managerial practices, cultivar characteristics, crop history, and prevailing weather. MoreCrop can use past managerial decisions to reconstruct previous disease conditions, assist the user in reasoning what disease control option to select, and provide disease-related as well as cultivar-related information for teaching and extension. MoreCrop provides information, suggestions, and a library of information. The expert system has been used for teaching, extension, research, and grower decisions. The program is being updated and expanded to include new information on cultivars, disease resistance, seed treatments, foliar sprays, geographical regions, agronomic zones, and cost-benefit relationships; is being modified to utilize new computer technology so that it will be more effective over a wider range of conditions; and is being expanded to other regions of the U.S. The current system is being distributed by Cooperative Extension at Washington State University.
Publications.
Adams EB and Line RF. 1997. Plant Diseases. Washington State University Cooperative Extension Bulletin EB1839, October.
Chen XM, Line RF, and Leung H. 1997. Genome scanning for resistance gene analogs using high resolution electrophoresis. Phytopath 87:S18 (Abstract).
Chen XM, Line RF, and Leung H. 1997. Recessive Inheritance of Resistance in Barley to Races of Puccinia striiformis f sp. hordei. Phytopathology 87:S18 (Abstract).
Chen XM, Line RF, and Leung H. 1997. Genome Scanning for Resistance gene analogs ... electrophoresis. Theor Appl Genet (Accepted for publication 8/97).
Line RF. 1997. Successful control of smuts and bunts of wheat treatments. Xth Biennial Workshop on the Smut Fungi. Agri-Food Canada, Lethbridge, Alberta, Canada. pp 11-14.
Line RF. 1997. Use of foliar fungicides to assess winter wheat yield losses caused by stripe rust, leaf rust, and powdery mildew, 1996. Fungicide and Nematicide Tests 52:216-218.
Line RF. 1997. Control of stripe rust and powdery mildew of wheat with seed treatments and foliar sprays, 1996. Fungicide and Nematicide Tests 52:219-222.
Line RF. 1997. Control of stripe rust and powdery mildew of winter wheat in southeastern washington with foliar fungicides, 1996. Fungicide and Nematicide Tests 52:223-225.
Line RF. 1997. Control of stripe rust and powdery mildew of winter wheat in eastern washington with foliar fungicides, 1996. Fungicide and Nematicide Tests 52:226-229.
Line RF. 1997. Effect of application of foliar fungicides. Wheat, 1996. Fungicide and Nematicide Tests 52:230-231.
Line RF. 1997. Control of flag smut of wheat with seed treatments, 1996. Fungicide and Nematicide Tests 52:329.
Line RF. 1997. Control of common bunt of wheat with seed treatments, 1996. Fungicide and Nematicide Tests 52:330.
Line RF. 1997. Control of dwarf bunt of wheat with seed treatments, 1996. Fungicide and Nematicide Tests 52:331.
Line RF. 1997. Barley stripe rust in the pacific northwest in 1997. Highlights of research progress, Washington State University, Dept of Crop and Soil Sciences, TR97-1:75-78.
Line RF. 1997. Stripe rust, leaf rust and stem rust of wheat, 1997. Highlights of research progress, Washington State University, Dept of Crop and Soil Sciences, TR97-1:79-81.
Line RF. 1997. The smuts and bunts of wheat, 1997. Highlights of research progress, Washington State University, Dept of Crop and Soil Sciences, TR97-1:82-85.
Line RF. 1997. 1997. Further development of the expert system. Production. Highlights of research progress, Washington State University, Dept of Crop & Soil Sciences, TR97-1:86.
Line RF. 1997. Quarantines for control of flag smut: Are they effective or necessary? American Phytopathological Society Technical Program, 19-13 Aug. p. 77 (Abstract).
Line RF. 1997. Control of rusts and smuts in western United States, 1997.
Ann Wheat Newslet 43:353-354.
Selection of white kernel mutants from Chinese Spring wheat.
R.L. Warner, D.A. Kudrna, S.C. Spaeth, and S.S. Jones.
Wheats with red seed coat color generally have greater dormancy and/or resistance
to sprout than those with white seed coats. These observations have lead
to alternative hypotheses that the R genes have pleiotropic effects
on coat color and dormancy, or that the R genes are linked closely to dormancy
genes. The actual situation may be some combination of the two hypotheses.
Dormancy in white wheats is conferred by recessive genes similar to the
situation in barley, whereas maternal effects associated with the red pigment
(phlobaphenes) have been observed in red wheats. In an effort to more directly
determine the influence of red seed coat color on dormancy in wheat, we
selected and characterized white-seeded mutants from Chinese Spring.
A pure line selection of the Chinese Spring doubled haploid line Dv418 (obtained from Jan Dvorak, University of California, Davis) was chosen as the parent, because this genotype is homozygous and homogenous, has a phenotype unlike any cultivar in the PNW, and has a single gene for red color (R1). Seeds were treated with NaN3 as a mutagen; the M1 seeds were sown in the field at a high density to minimize tillering, and the M2 heads were harvested in bulk at maturity. Because red kernel color is due to a pigment in maternal tissue (testa), selection for white kernel color was conducted in the M3 generation (M2 maternal tissue). The M3 generation was produced in the greenhouse from approximately 20,000 M2 seeds planted in 77 shallow flats (25 x 50 x 5 cm). To minimize selection of duplicates of the same mutation, six seed from each of 40 M2 heads were planted in each flat. At maturity, M3 heads in each flat were harvested, and the kernels from each head visually examined for color. Kernels from prospective white mutant selections were treated with sodium hydroxide to enhance detection of the red phlobaphene pigment. Two putative white mutants, CSW01 and CSW02, were selected. Both selections came from the same flat and may be derived from the same mutational event.
Progeny tests confirmed that CSW01 and CSW02 are white-kernel mutants of Chinese Spring; both have seed storage protein electrophoretic banding patterns and plant morphological characteristics indistinguishable from those of Chinese Spring. Test crosses showed that the gene conferring white kernel color in the mutants is recessive and allelic to the r1 gene in domestic white-kernelled cultivars.
To determine the effect of the mutations on seed dormancy, CSW01, CSW02, and Chinese Spring were grown in the field and in the greenhouse at Pullman, WA. To minimize variation in dormancy caused by environmental effects and after-ripening, heads were harvested within a few days after reaching 'harvest ripeness', dried for 3 days at room temperature, and then stored in a freezer at 15°C. Dormancy was estimated by determining germination rates at 30, 24, and 17°C, and by the rate of after-ripening at 37°C. All three genotypes exhibited significant seed dormancy that gradually dissipated during dry storage at 37°C. However, the white mutants germinated somewhat more rapidly at 30°C than the red genotype. These results indicate that the gene conferring red color is probably not the primary dormancy factor in wheat caryopses but could have a pleiotropic effect on expression in caryopses exhibiting dormancy. Alternatively, if the R gene encodes a DNA binding protein, it possibly could have pleiotropic effects on several traits, including phlobaphene biosynthesis and dormancy, and different alleles could result in differential expression of the genes controlling these traits. To test this hypothesis, we will attempt to recover white-seeded deletion mutants using fast neutron radiation as a mutagen.
Spring wheat breeding and genetics program.
K. Kidwell, B. Barrett, V. DeMacon, and G. Shelton.
Cultivar development and genetic mapping efforts.. Over 400 crosses were made in 1997, and novel genes conferring resistance to the Hessian fly and Russian wheat aphid were incorporated into adapted soft white, hard red, hard white, and spring club germplasms. F1 seed from 422 lines was increased to generate segregating progenies for use: 1) in backcross breeding strategies; 2) in protein marker-assisted selection for end-use quality improvement; 3) as genetic mapping populations for identifying DNA markers linked to disease resistance, insect resistance, and spring growth habit genes; and 4) in the conventional cultivar development program. Approximately 1,400 F2, 666 F3, and 693 F4 families were advanced to the next generation, and 12,140 F5 lines were evaluated in the field for agronomic characteristics. Over 800 F6 lines were evaluated in multiple field trials, and grain samples from 350 lines with superior agronomic performance were sent to the Western Wheat Quality Laboratory for quality assessment. Seventh generation lines (178) were evaluated in replicated field trials, and 219 advanced lines (F8+) were evaluated at 3-12 locations under annual crop, crop/fallow, and irrigated conditions. High molecular weight glutenin proteins are used routinely in a marker-assisted selection strategy to identify individuals within segregating progenies with superior end-use quality potential for advancement in the breeding program. Genetic mapping efforts are underway to identify DNA tags linked to disease resistance (strawbreaker foot rot), insect resistance (Hessian fly and Russian wheat aphid), and spring growth habit (SGH) genes for use as selection tools for cultivar development.
Variety releases and advanced lines with potential for release. WA007802, a HRSW cultivar named Scarlet, was approved for variety release. Scarlet is targeted for production in the semi-arid region of eastern WA as a replacement for Butte 86, a tall, hard red variety from North Dakota. Scarlet has outstanding grain yield potential and milling properties with a grain protein content similar to that of Butte 86 when grown in the targeted production region. Registered seed will be available for commercial production in 1999.
The semidwarf, soft white, experimental line, WA007850, may be suitable as a replacement for Penawawa in the higher rainfall zones of eastern WA. In 1997, WA7850 had a 2 bu/A higher yield average across locations than Penawawa. The test weight of this line is similar to that of Penawawa; however, WA007850 has a lower grain protein content. Preliminary data indicate that WA7850 may be resistant to stripe and leaf rust, and the end-use quality of this line outstanding. WA007850 will be proposed for release in 1999. (K. Kidwell, G. Shelton, V. DeMacon)
Incorporating insect resistances into adapted cultivars. Hessian fly is one of the most destructive pests of wheat and has spread to almost all principal wheat-producing areas including Washington state. This pest is controlled most efficiently through the use of resistant cultivars and/or by planting spring wheats early enough to avoid infestation. Currently, only a few Hessian fly-resistant spring wheat cultivars are available, and all of these carry the same resistance gene even though 23 other sources of resistance have been identified. The Russian wheat aphid also can be problematic in Washington, particularly in dryland areas or in spring wheat fields that were planted late in the growing season. Several dominant resistance genes to RWA have been identified; however, no RWA resistant spring wheat cultivars have been released in the PNW. Six new resistance genes for Hessian fly and five for RWA have been incorporated into adapted spring wheat cultivars from three generations of backcross breeding. Seed of segregating progenies was sent to Kansas State and Oklahoma State Universities for insect screening for Hessian fly and RWA resistance, respectively. Resistant lines were sent back to Pullman for seed increase, and advanced material from these lines will be evaluated in the field in 1998. (K. Kidwell, J. Hatchett (KSU), C. Baker (OSU), V. DeMacon, G. Shelton)
Genetic diversity assessment of wheat genotypes. Evaluating genetic diversity among regionally adapted germplasm may expedite crop improvement. The objectives of this study were to i) use amplified fragment length polymorphisms (AFLPs) to assess genetic diversity among wheat cultivars adapted to the U.S. Pacific Northwest, ii) compare AFLP-based genetic diversity estimates (GDEAFLP) for hypermethylated and hypomethylated portions of the wheat genome, and iii) compare GDEAFLP and pedigree-based GDE (GDEPED) data. Fifty-four spring or winter wheat cultivars were evaluated. Eight PstI:MseI (methylation sensitive) and eight EcoRI:MseI (methylation insensitive) primer pairs generated a total of 111 and 118 polymorphic bands, respectively. Ordination and cluster analyses and the analysis of molecular variance indicated that diversity among these cultivars is arranged hierarchically. The highest diversity levels are between spring and winter growth habit types, intermediate levels are between cultivars from different market classes within growth habit, and the lowest level of diversity is among cultivars within market class. The mean PstI-based diversity estimate was lower than the mean EcoRI-based estimate (0.51 vs. 0.58, p < 0.0001), suggesting that methylated regions of the wheat genome are more diverse than unmethylated regions. Comprehensive pedigree information for a subset of 45 cultivars was used to calculated GDEPED. Eighty-nine percent of the GDEPED values indicated < 10 % of the DNA in the cultivars under consideration was identical by descent. In contrast, > 88 % of AFLP fragments were monomorphic. GDEAFLP may more accurately reflect the level of allelic variation among genotypes than GDEPED. (B. Barrett and K. Kidwell)
Developing a nondestructive, PCR-based, marker-assisted selection procedure for strawbreaker foot rot resistance in winter wheat. Strawbreaker foot rot is a devastating disease of winter wheat grown in the Pacific Northwest. At least two genes (Pch1 and Pch2) have been identified that confer resistance to this disease, and two resistant winter wheat cultivars, Hyak and Madsen, are available for commercial production. During the genetic diversity assessment analysis, an AFLP fragment was identified that was present only in these two cultivars This fragment is a putative DNA-tag for strawbreaker foot rot resistance. The objective of this study is to develop a nondestructive, PCR-based DNA marker for strawbreaker foot rot resistance. (G. Iryzk, B. Barrett, K. Kidwell, S. Jones and T. Murray)
Enhancing hybrid wheat performance via intergrowth habit crosses.
Spring wheat typically accounts for 10-15 % of the acreage sown to wheat
in the state of Washington each year. Even though producing winter wheat
on the rolling hills of the Palouse has resulted in enormous soil losses
from wind and water erosion, winter wheat production predominates, because
it is more profitable than producing spring wheat. Improving the profit
margins for spring wheat production would provide growers with a feasible
option to winter production, which would have the added benefit of reducing
soil erosion. The key to making spring wheat production more profitable
is to increase its grain yield potential. Since 1995, crosses between spring
and winter types have been made to convert adapted winter wheat cultivars
to spring types for reseeding purposes. The following observations were
made: 1) hybrids between spring and winter crosses do not require vernalization
to set seed, 2) heading dates of hybrids differ depending on which cultivar
(winter or spring) is used as the female parent when making the cross, and
3) hybrids generated through crosses between growth habits are much more
vigorous than traditional (within growth habit) spring wheat hybrids. The
objective of this study is to compare agronomic performance of adapted hybrid
wheat varieties generated through crosses between and within growth habit
with the field performance of their inbred parents. Data will be used to
1) test for maternal effects on hybrid vigor, 2) estimate general and specific
combining abilities of parents, 3) assess the variation in grain yields
of the various hybrids, and 4) investigate maternal impacts on end-use quality
of hybrid wheat. In addition, the association between heterosis levels and
diversity estimates derived from AFLPs and yield QTL-associated RFLPs will
be determined to assess the predictive utility of DNA marker based genetic
diversity estimates for identifying superior parental combinations for hybrid
wheat production. (K. Kidwell and B. Barrett)
Monitoring genetic responses of diverse wheat populations to selection
in direct seeded vs. conventional tillage systems. Direct seeding is
an effective method for controlling soil erosion resulting from intensive
crop production. However, eliminating tillage passes increases soil moisture
levels, reduces soil temperatures and alters fungal pathogen activities
compared to conventionally tilled fields. Little information concerning
the feasibility of improving the adaptation of wheat varieties to direct
seeding systems is available. The objective of this study is to monitor
allele frequency changes in progenies of identical parentage that were selected
simultaneously in no-till and conventional tillage systems using AFLP analyses.
(K. Kidwell, R. Allan and J. Smith)
Publications.
Barrett BA. 1997. Molecular and pedigree-based assessment of genetic diversity among wheat cultivars from the Pacific Northwest. M.S. Thesis. Washington State University, Dept of Crop and Soil Sciences.
Barrett BA and Kidwell KK. 1997. Assessing genetic diversity among regionally adapted wheat (Triticum aestivum) germplasm. Western Soc Crop Sci, Corvallis, OR. p. 40.
Barrett BA and Kidwell DD. 1998. AFLP-based genetic diversity assessment among wheat cultivars from the Pacific Northwest. Crop Sci (accepted).
Donaldson E and Kidwell KK. 1997. 1997 spring wheat variety trial results. In: The Green Sheet, weekly newsletter. Washington Association of Wheat Growers. 31 October, 1997.
Kidwell KK, Barrett BA, DeMacon V, and Shelton G. 1997. Spring wheat breeding and genetics: 1996 progress report. In: 1997 Field Day Proceedings: Highlights of Research Progress (Donaldson E ed). Cooperative Extension, Washington State Univ, Dept of Crop and Soil Sciences, Technical Report 97-1. pp. 18-20.
Kidwell KK, Donaldson E, DeMacon V, Shelton G, and Reisenauer P. 1997. Spring wheat variety testing results for 1996 and 1997. In: Wheat Life, Washington Association of Wheat Growers' Official Publication. December 1997, 40(11):68-72.
Kidwell KK, Donaldson E, Reisenauer P, Shelton G, DeMacon V, Davis M, and Miller B. 1997. 1996 spring wheat variety performance data. In: 1997 Field Day Proceedings: Highlights of Research Progress (Donaldson E ed). Cooperative Extension, Washington State Univ, Dept of Crop and Soil Sciences, Technical Report 97-1. pp. 21-26.
Kidwell KK, Miller B, Reisenauer P, Davis M, and Shelton G. 1997. 1996 spring wheat variety evaluation trials. In: Wheat Life, Washington Association of Wheat Growers' Official Publication. December 1997, 40(11):48-53.
Linscott TM, Kidwell KK, Schotzko D, Bosque-Perez N, and Zemetra RA. 1997. Developing molecular markers for resistance to Russian wheat aphid in soft white winter wheat. Agron Abstrn p. 82.
Miller BC, Jones SS, Ullrich SE, Donaldson E, Kidwell KK, Anderson JA, and Goemmer C. 1997. 1996 Cereal Variety Evaluation Results. Cooperative Extension, Washington State Univ, Dept of Crop and Soil Sci, Technical Report 97-2.
Morris CF, Shakley BJ, King GE, and Kidwell KK. 1997. Genotypic and environmental variation for flour swelling volume in wheat. Cereal Chem 74(1):16-21.
USDA-ARS Western Wheat Quality Laboratory.
C.F. Morris, A.D. Bettge, H.C. Jeffers, G.E. King, M. Giroux, B. Patterson, D.A. Engle, M. Baldridge, B. Davis, and R. Ader.
Research continues to focus on the areas of grain hardness, starch quality,
and noodle color / polyphenol oxidase (PPO). The WWQL leads the PNW Wheat
Quality Council and functions as the lead lab in assessing the end-use quality
of wheat breeding lines in the PNW.
Publications.
Bettge AD and Morris CF. 1997. Pentosan and protein content of hard and
soft wheat amyloplast membranes. Cereal Foods World 42:626 (abstract).
Giroux MJ and Morris CF. 1997. Structure and presence of the amyloplast
membrane proteins, puroindolines, are associated with wheat grain hardness.
Plant Physiol 114(s):46 (abstract).
Giroux MJ and Morris CF. 1997. A glycine to serine change in puroindoline b is associated with wheat grain hardness and low levels of starch-surface friabilin. Theor Appl Genet 95:857-864.
Giroux MJ and Morris CF. 1997. Wheat grain hardness results from highly conserved mutations in the friabilin components puroindoline a and b. Proc Natl Acad Sci USA (In press).
Giroux MJ, Babb S, and Morris CF. 1998. Wheat grain hardness is controlled by highly conserved puroindoline mutations. PVI, San Diego, CA, January 1998. P. 119.
Miller RA, Hoseney RC, and Morris CF. 1997. Effect of formula water on the spread of sugar-snap cookies. Cereal Chem 74:669-671.
Morris CF. 1997. The functionality of lipids in wheat foods. In: New Approaches to Functional Cereals and Oils, Proc Inter Symp (Shizhong S and Ruizheng L eds). Chinese Cereals and Oils Assn., Beijing, China. pp. 518-521.
Morris CF, King GE, and Rubenthaler GL. 1997. The role of wheat flour fractions in variation for peak hot paste viscosity. Cereal Chem 74:147-153.
Morris CF, Jeffers HC, Zeng M, King GE, Bettge AD, Giroux MJ, and Engle DA. 1997. Biochemical - Genetic determinants of noodle quality. Cereal Foods World 42:669 (abstract).
Morris CF, Jeffers HC, Bettge AD, Giroux MJ, Engle DA, Baldridge ML, Patterson BS, Ader RL, King GE, Davis BC, Kelley W, and Seibol L. 1997. Activities of the USDA/ARS Regional Wheat Quality Laboratories. III. Western Wheat Quality Laboratory. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance, Manhattan, Kansas. P. 499.
Morris CF, Shackley BJ, King GE, and Kidwell KK. 1997. Genotypic and environmental variation for flour swelling volume in wheat. Cereal Chem 74:16-21.
Zeng M, Morris CF, Batey IL, and Wrigley CW. 1997. Sources of variation for starch gelatinization, pasting and gelation properties in wheat. Cereal Chem 74:63-71.