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Growing Bread Wheat in the Mid-Atlantic Region

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					                                                                                                                                                              PUBLICATION 424-024


                            Growing Bread Wheat
                          in the Mid-Atlantic Region
                W.E. Thomason, Assistant Professor and Extension Grain Crops Specialist, Virginia Tech
                            C.A. Griffey, Professor and Small Grain Breeder, Virginia Tech
               M.M. Alley, W.G. Wysor Professor of Agriculture and Soil Fertility Specialist, Virginia Tech
                       E.L. Stromberg, Professor and Extension Plant Pathologist, Virginia Tech
                           D.A. Herbert, Professor and Extension Entomologist, Virginia Tech
                          E.S. Hagood, Professor and Extension Weed Scientist, Virginia Tech

Introduction                                                                                   Wheat Classes
The more than 55 million people who live in the mid-                                           Wheat is grouped into market classes associated with
Atlantic region of the United States want to purchase                                          the type of wheat grown and its intended end-use.
processed grain foods such as bread and other dough                                            Wheat classes are determined not only by the time of
products made from hard, or bread, wheat. To meet                                              planting and harvest but also by hardness, color, and
this demand, regional mills import bread wheat, which                                          shape of the kernel. Wheat within each class has simi-
comes almost exclusively from the Plains states. These                                         lar characteristics as related to milling, baking, and
imports make up approximately 30 percent of the total                                          food-use qualities.
grain needed for the region. Because the market exists
                                                                                               The major classes are hard red winter wheat (HRWW),
for bread wheat, and because it is usually of higher value
                                                                                               hard red spring wheat, soft red winter wheat (SRWW),
than soft wheat, growers are interested in using adapted                                       durum, hard white wheat, and soft white wheat. A
cultivars and developing agronomic techniques to grow                                          complete description of these wheat classes and their
bread wheat in the mid-Atlantic region. Millers also are                                       uses can be found at the U.S. Wheat Associates website
interested because their transportation costs, and thus                                        (www.uswheat.org/everyNeed/wheatClasses). Hard red
their total cost, would be greatly reduced if they could                                       winter wheat is usually grown in semi-arid regions, has
by the bread wheat within the mid-Atlantic region.                                             a wide range of protein content, usually averaging near
                                                                                               12 percent, and has good milling and baking character-
At this time, bread-wheat marketing is solely through                                          istics for producing bread, rolls, and all-purpose flour.
contracts with elevators and/or millers. Identity pres-                                        Soft red winter wheat is grown primarily in higher rain-
ervation, high quality, and preplanned marketing is                                            fall areas. It is generally higher yielding than HRWW,
necessary to garner increased value from the grains                                            but has lower protein content, usually less than 10 per-
needed by the mills, because the majority of wheat pro-                                        cent, and has good milling and baking properties for
duced in the mid-Atlantic region is, and will continue                                         cookies, cakes, crackers, and some flat breads. Soft
to be, soft wheat.                                                                             white wheat is grown mainly in the Pacific Northwest,
                                                                                               Michigan, Wisconsin, and New York. Its protein con-
The purpose of this publication is to provide an under-                                        tent is similar to SRWW, and the flour is used mainly
standing of wheat classes in the market place and                                              for making cakes, muffins, cookies and pastries. Hard
outline production practices most appropriate for high-                                        white wheat is a relatively new wheat class. It is closely
quality bread-wheat production in the mid-Atlantic                                             related to the HRWW but has a milder, sweeter flavor
region, which is characterized by high humidity and                                            and is used mainly in yeast breads, hard rolls, bulgur,
moderate temperatures.                                                                         and oriental noodles. Durum wheat has the hardest ker-

                                                                               www.ext.vt.edu
                                      Produced by Communications and Marketing, College of Agriculture and Life Sciences,
                                                    Virginia Polytechnic Institute and State University, 2009
                             Virginia Cooperative Extension programs and employment are open to all, regardless of race, color, national origin, sex, religion,
                             age, disability, political beliefs, sexual orientation, or marital or family status. An equal opportunity/affirmative action employer.
                             Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University,
                             and the U.S. Department of Agriculture cooperating. Mark A. McCann, Director, Virginia Cooperative Extension, Virginia Tech,
                                              Blacksburg; Alma C. Hobbs, Administrator, 1890 Extension Program, Virginia State, Petersburg.
nels of all U.S. wheat. It is a spring wheat that is grown         Production Programs
mainly in the northern Great Plains. Durum wheat is
used to make semolina flour for pasta production.                  Cultivar Selection
                                                                   Cultivar selection may be the most important manage-
Wheat Kernel Properties                                            ment decision made in bread-wheat production. Yield
                                                                   potential is important and typically the first consider-
Over 80 percent of the weight of the wheat kernel is               ation when choosing a cultivar; however, end-use quality
starchy endosperm, the part of the kernel that is milled           and product consistency are of equal importance when
to produce flour. Endosperm cells consist of tightly               selecting cultivars to be produced for specific markets.
packed starch granules and seed storage proteins. Sur-             Decisions on which cultivar to plant should be based on
rounding the starch granules is a matrix of gluten-                performance data, including disease resistance, insect
forming proteins. The physical base for determining                resistance, heading dates, lodging rates, height, test
endosperm hardness is the binding strength between                 weight, and yield. Spreading risk by planting several
the starch granules and protein matrix. In soft wheat,             cultivars with appreciably different maturity is recom-
the starch granules are loosely attached to the protein            mended, especially if large acreage is planned.
matrix. Soft wheat is easy to grind and produces fine-
textured flour. The binding of the starch granules to              No cultivar is well-suited for all environments or loca-
the protein matrix is much stronger in hard wheat and              tions. Cultivar selection should consider the production
more force is required to crush the kernel. This results           scheme and area where it is to be grown. If plans are
in coarse-textured flour with more broken starch gran-             to double-crop soybeans following wheat, early matur-
ules. Hard, or bread, wheat flour is generally preferred           ing cultivars are the most appropriate. Many early
for any kind of yeast-leavened bread because damaged               maturing cultivars are more at risk for exposure to late
starch granules increase water uptake, resulting in soft           spring frost when planted early in the recommended
bread. Broken starch granules are also more readily                planting period. Planting these cultivars later in the
hydrolyzed by alpha-amylase, providing more ferment-               recommended planting window is the best way to avoid
able sugars for the yeast. Increased water absorption              excessive growth or very early heading.
is not desirable in soft wheat flour because many soft
                                                                   Genetic resistance is the simplest and least expensive
wheat products are baked to low moisture content, and
                                                                   defense mechanism against diseases and insects. While
are relatively dense compared to breads.
                                                                   no cultivar is completely immune to all diseases and
Wheat Class and                                                    insects, wide differences do occur and these factors
                                                                   should be included when making decisions on genetics.
Production Region                                                  Annual evaluation of cultivar selection is necessary to
Growing environment, genotype, and the interaction                 ensure that disease population changes have not reduced
between these factors greatly influence the yield and end-         the usefulness of the genetic resistance of particular
use quality of wheat. Environmental factors such as tem-           cultivars.
perature, rainfall, and day length are beyond the control          Similar to other traits, cultivars vary in straw strength
of managers. However, environmental conditions have                and height. Select cultivars with good straw strength
favored the selection of certain types of wheat in various         to prevent harvest losses associated with lodging,
regions. For example, in semi-arid regions, hard wheat
                                                                   especially under high-yield management schemes. A
cultivars have relatively low yields but high protein con-
                                                                   shorter stem height and less straw are favorable when
tent because the protein accumulates relative to starch
                                                                   double-cropping wheat with soybeans. Taller cultivars
in the kernels. In humid regions, soft wheats have been
                                                                   are generally preferred when straw is to be harvested.
favored because the climate is favorable to higher yields,
resulting in a dilution of the protein level in the kernels.       The growing environment greatly influences grain test
However, inputs that affect the growing environment,               weight, but this trait is also controlled by genetics, which
such as seeding rate, fertilizers, herbicides, fungicides,         determines the inherent maximum test weight potential
etc. are controlled by managers. Recent breeding efforts           of a given cultivar. Because the intended market for
have developed more adapted hard wheat cultivars for               this product is flour, the total flour yield of the grain is
growth in humid climates, and research has developed               important. While test weight is not directly associated
improved nitrogen and sulfur fertilization techniques for          with flour yield or end-use quality, grain that is sound,
increasing protein content.                                        not weathered or sprouted, is required for good milling

                                                               2
and baking quality. Grain soundness and lack of weath-            The availability of adapted HRWW cultivars is cur-
ering are the most critical determinants of good end-use          rently limited in the mid-Atlantic region because plant
quality, and is why test weight is used to screen wheat,          breeders have only recently focused on developing this
even though test weight is not directly correlated to flour       type of wheat. Domestically available cultivars being
yield from grain or baking properties. However, grain             tested along with cultivars imported from Europe have
exposure to rainfall following physiological maturity             shown promise, both with respect to yields and quality.
until harvest greatly reduces end-use quality and value,          Available HRWW cultivars generally yield less than our
and such exposure usually lowers the test weight. Upon            best adapted SRWW cultivars, according to data from
ripening, harvesting grain at high moisture and drying            the Virginia Elite and Uniform Regional Bread Wheat
it is one means of ensuring that the grain has high end-          Trials. Growers should carefully consider the potential
use quality, and a high test weight. A test weight signifi-       yields and contract price premiums before deciding to
cantly below 58 pounds per bushel (the standard for #2            grow bread wheats in the mid-Atlantic region. How-
US wheat) will probably result in a lower price received          ever, we anticipate that yield potential will increase as
or may even exclude the wheat from being purchased                plant breeders develop cultivars specifically adapted to
for the purpose of milling for bread-wheat flour. Culti-          this region.
vars with genetically high test weight will more readily
withstand wet harvest conditions and still achieve high
test weights when compared to cultivars that have low             Seeding
maximum test weights.                                             In addition to genetic selection, planting decisions
                                                                  significantly impact the final yield. These planting
Once the cultivars have been selected, using certified            decisions include seedbed preparation, planting date,
seed increases the likelihood of obtaining the necessary          seeding rate, and seeding depth. Planting timeliness
qualities of cultivar assurance and purity, high germi-           and precision are key factors in obtaining the best yield.
nation rate, and freedom from weed seeds. Research                The key to building high yield potential is to establish
consistently shows that certified seed out performs bin           an appropriate population on time for the particular
run seed for stand establishment, early season vigor,             area and to achieve a uniformly emerging wheat crop.
and yield and decreases the introduction of weeds. The
extra profit from certified seed more than compensates            Planting date is a critical component of successful wheat
for the higher seed cost. Because end-use quality is              production. Optimum yield potential is only achieved
paramount to success in identity-preserved markets                when planting occurs within the recommended window.
and end-use quality depends largely on the genetics               This window for optimum yields is usually the date of the
of a cultivar, using certified seed is probably the only          first annual fall freeze plus or minus one week. Improper
means to ensure cultivar identity and end-use quality.            cultivar selection, poor seed quality, late planting, incorrect




Figure 1. Suggested winter bread-wheat planting
dates for Virginia.


                                                                                                 October 20–30

                October 5–15




                                                                                    October 25–November 5

                                                              3
plant population, and incorrect seeding depth cannot be           Because of the tendency for slower fall growth with no-
overcome with in-season management practices. Figure 1            tillage, extra effort should be expended to plant slightly
has suggested planting dates across the commonwealth.             earlier than with conventional tillage small-grain crops.
                                                                  This gives more time for tiller development in warmer
These dates were determined based on evaluation by the            weather. With earlier planting, it is important to con-
Virginia Agricultural Statistics Service of 50 percent fall       sider using cultivars with medium to late heading dates
freeze probability for over 90 sites in Virginia. Planting        or those that are day-length sensitive regarding initia-
wheat earlier than the recommended period will sub-               tion of heading to lessen the chance of spring freeze
ject it to greater insect and disease pressure and subse-         damage.
quently to more winter injury. Although wheat emerges
sooner and the shoot develops faster in warm soil, the            It is important that seed be placed at least 3/4 inch
root system develops much faster and more extensively             below the soil surface, not counting the residue layer
if the soil is cool. Planting later than the recommended          in no-tillage seeding, to reduce the potential for winter
date may be even more detrimental to yield potential.             kill from frost heaving and root and crown exposure to
Late-planted wheat will have fewer tillers, and thus              freeze injury. Too often in no-tillage production, seed
fewer heads and reduced yield potential. Recommended              is planted too shallow and germinates because of the
seeding rates at various planting dates for bread-wheat           residue coverage, but then cold temperatures cause sig-
cultivars are shown in Table 1.                                   nificant winter-kill.

Table 1. Recommended seeding rates for bread
wheat in Virginia Tech.                                           Fertilization
                                                                  The recommended rates and timing for lime and fer-
Planting Time                                                     tilizer applications are similar to those for SRWW
  Row Width          On-time        Two Weeks Late                production. Nitrogen Management for Winter Wheat:
   --inches--             ---seeds/row foot---                    Principles and Recommendations, Virginia Coop-
                                                                  erative Extension publication 424-026, http://pubs.ext.
        6               22                       24               vt.edu/424-026/ and Intensive Soft Red Winter Wheat
        7               24                       26               Production, Virginia Cooperative Extension publi-
                                                                  cation 424-803, http://pubs.ext.vt.edu/424-803/ have
       7.5              25                       28
                                                                  more information on these subjects. If lime is required
        8               26                       29
                                                                  as indicated by a soil test, it should be spread and, if
                                                                  possible, incorporated with tillage prior to beginning
Virginia research demonstrates that seeding rates for             no-tillage production. Surface application of lime is
current bread-wheat cultivars in a conventional, tilled           an acceptable practice but the pH will be affected in
seedbed should be at least 43 seeds per square foot               a much smaller layer of soil. Soil samples should be
(25 seeds per row foot in 7.5 inch rows) to approach              taken from the depth of the plow layer in tilled fields
optimum yields. Initial results support the conclusion            and to a four-inch depth in no-tillage fields. Because
that seeding at 45 to 50 seeds per square foot is appro-          early plant growth and tillering are often slower than
priate for sites with high yield potential (>75 bushels           with conventional production, topdressing nitrogen (N)
per acre). Increased seeding rates are advisable when             is especially critical with no-tillage seeding. Pay close
planting later than optimum and/or with no-tillage                attention to the tiller density in the late fall and winter
planting. It is advisable to increase no-tillage seeding          and apply N as recommended to develop the optimum
rates by 10 percent over conventional rates when plant-           number of tillers to support high yields. This is espe-
ing into heavy residue, such as corn stover, or when              cially important with later plantings.
soil conditions make it difficult to maintain a constant
planting depth. Increasing seeding rates generally is             Baking quality of bread-wheat flour typically increases
not necessary when planting after soybeans or when                with increased grain protein and a minimum of 12 per-
residue levels are not extremely high. If producers are           cent protein is desirable for bread baking. Protein and
growing both conventional and no-tillage wheat, it                starch concentrations of wheat are inversely related;
would be advisable to plant bread-wheat cultivars with            therefore, conditions that favor high yields typically
conventional tillage, because no-tillage wheat often              favor low protein, and vice versa. One way to overcome
yields slightly less than conventionally planted wheat.           this and increase grain protein is with a late-season

                                                              4
foliar application of N directly to the crop. Virginia          latest edition of the Virginia Cooperative Extension Pest
research has found that 30 to 40 pounds per acre of N           Management Guide, publication 456-016, http://pubs.
as low-biuret urea dissolved in water applied between           ext.vt.edu/456-016/ or your local Extension agent for spe-
growth stage (GS) 45 and 54 will increase grain pro-            cific information on appropriate herbicides and applica-
tein, even when previous N applications have been               tion strategies.
sufficient to support high yields (Figure 2). Low-biuret
urea has reduced potential for foliar burn and dissolves
more easily than granular or prilled urea. However,
                                                                Insect Management
both granular and prilled urea are acceptable for foliar        With a few exceptions like cereal leaf beetle and aphid
application. These materials dissolve more easily in            transmitted barley yellow dwarf (BYDV), insects have
warm water and should be strained to remove particles           historically not been a major problem in Virginia small
associated with anti-caking and sealing agents.                 grains. However, damage has occasionally been severe
                                                                and certain pests could become more common with
In some instances, the addition of 30 pounds per acre           an increase in reduced or no-tillage practice across the
of sulfur (S) at GS 30 (jointing) is also important to          state. Traditionally, producers have avoided damaging
achieving desirable grain protein levels. Figure 2 dem-         populations of Hessian fly and the risk of high levels
onstrates the synergistic relationship between GS 30 S          of aphid attack and BYDV by planting later in the fall.
and late season (GS 45) N on grain protein observed in          The need to establish no-tillage small grains earlier
Virginia research.                                              exposes the crops to more pressure from these insects
                                                                and increases the risk of economic damage. Insect
Grain protein response to S depends on soil S avail-            pests such as cutworm/fall armyworm, the wheat curl
ability. If the soil supply is low, then supplemental S         mite, and Hessian fly are associated with fields where
fertilizer is crucial to achieving high grain protein.          producers have continuous wheat/soybean rotations,
The best way to evaluate this is through tissue testing.        or where volunteer grain in soybean fields is present
An N : S ratio above 15:1 indicates a likely grain-yield        when fall grain crops are planted. Volunteer small
response to S fertilizer and a ratio above 10:1 a protein       grain serves as a “green bridge” for these pests and
response.                                                       can lead to infestation problems. Producers should be
                                                                vigilant when scouting for insects in small grains. For
                                                                insect population threshold levels and control options
Weed Control                                                    available see the latest edition of the Pest Management
All herbicides that are labeled for use in SRWW (e.g.           Guide Field Crops, Virginia Cooperative Extension
Harmony Extra, Harmony GT, Peak, 2,4-D, Hoelon,                 publication 456-016, http://pubs.ext.vt.edu/456-016/ or
Osprey) are acceptable for use in bread wheat. See the          your local Extension agent.

Figure 2. Bread wheat response to rates of foliar N at GS 45 with and without 30 pounds per acre of sulfur at
GS 30.

                      12.5                 y = -0.0004x2 + 0.0412x + 11.218
                                 +S                  R2 = 0.9999
  Grain Protein (%)




                       12
                                 -S


                      11.5                                                  y = 0.0203x + 11.249

                                                                                R2 = 0.9954

                       11
                             0        10           20            30                        40                 50
                                                    N Rate (lb/ac)

                                                            5
Disease Management                                               and severity of FHB can dramatically increase if tem-
                                                                 peratures are optimal for infection. Depending on the
The fact that most currently available suitable bread-
                                                                 timing of the infection, one to several spikelets can be
wheat cultivars were developed in states having drier
                                                                 infected, colonized, and display a bleached appearance
climates typically means that disease resistance to the
                                                                 at a time when “healthy” spikelets are still green. The
most common pathogens in humid areas has not been
                                                                 grains produced in colonized spikelets may contain
fully evaluated, or has not been a selection criterion.
                                                                 mycotoxins that are harmful to livestock and humans.
This is especially the case for powdery mildew (PM).
                                                                 There is no effective fungicide treatment once the head
This disease can occur in the fall and persist through
grain filling and results in significant yield loss due to       is infected and colonized. As yet, there are no culti-
tiller mortality and reduced photosynthesis associated           vars available with complete resistance to initial FHB
with colonization of a large amount of leaf area. In two         infection. Similar to SRW wheat, some bread-wheat
years of Virginia testing, PM incidence has been low,            cultivars exhibit moderate resistance to the spread of
so we have seen no response to systemic fungicide seed           the pathogen from one colonized spikelet in the head to
treatment with low disease pressure. However, if cul-            others. When possible, it is advisable to select cultivars
tivar resistance to PM is rated as moderate to suscep-           with at least moderate resistance to FHB.
tible, a preventive treatment is recommended.
                                                                 More information about small-grain diseases is avail-
Foliar wheat diseases are also more severe in humid              able at the Integrated Disease Management in Small
environments. These include leaf rust, stripe rust, tan          Grains website (oak.ppws.vt.edu/stromberg/smallgrain/
spot, and Stagonospora leaf and glume blotch. Man-               sgrain.html).
agement of foliar diseases should be based on inte-
grated pest management techniques where treatment                Harvesting
decisions are based on scouting fields and assessing
the level of disease presence. Fields should be scouted          Harvest and dry wheat the first time it reaches 20 per-
weekly from GS 31 through 58 for disease incidence               cent moisture, or the first time it reaches 15 percent
and severity. For scouting techniques, threshold lev-            moisture, if drying is not possible. Make sure the com-
els, and available control options, see the latest edition       bine and all other critical equipment, including hauling
of the Pest Management Guide Field Crops, Virginia               equipment, are cleaned prior to harvest as contamina-
Cooperative Extension publication 456-016, http://               tion with foreign matter and other crop seeds will lead
pubs.ext.vt.edu/456-016/ or your local Extension agent.          to discounts and possibly rejection for bread milling.
                                                                 Set the combine properly and modify the cylinder
One especially damaging disease for winter wheat is              speed and/or concave clearance as harvest conditions
fusarium head blight (FHB), or scab, caused by the               change during the day. Your particular combine man-
fungal pathogen Fusarium graminearum. Head infec-                ual is the best place to go for information about set up.
tion is most severe when moist, warm weather occurs              Timely harvest to produce the highest quality possible
during flowering and fungal spores are present. If a rain        is needed to earn bread-wheat price premiums in our
event occurs during anthesis (flowering), the incidence          humid climate.




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