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XIII. Malting Barley Production Practices
MALTING BARLEY IN THE UNITED STATES
duction of barley for the malting market are more critical than for other
uses because the physical and chemical properties of the harvested grain
are of primary concern in the market.
Three general considerations confront a producer interested in growing
acceptable malting barley. First, the area of production must have the potential of growing grain of suitable quality. This factor is largely a matter
of environment, and past climatic history should provide the answer. There
are new frontiers for malting barley where history may be of little value
in determining successful production. However, these are small in number
and generally are associated with new irrigation developments or areas
where cropping practices can be changed in established irrigation districts.
Second, adapted barley varieties of acceptable quality must be available.
Third, a market for malting barley must be available. After these general
criteria have been met, several specific management decisions remain.
The general requirements of malting barley have been known for a long
time in relation to the period of time that this crop has occupied an important place in American agriculture. Information on barley production practices was summarized by Derr (191 1) and in bulletins by Harlan (1918,
1932) and Harlan and Wiebe (1943). Each of these authors referred to
culture of malting barley. Most states with significant malting barley acreages have published results on production practices and made these available to barley growers through extension bulletins and circulars. Although
some of the recommended practices have been modified as new research
data have been published, it is interesting to note the validity of recommendations made several decades ago to malting barley producers.
Selection of a variety by a malting barley grower involves two major
considerations. First, the variety must be adapted to the area and should
have as many of the agronomic characteristics as possible to fit the specific
conditions provided by the individual grower’s farming operations.
Medium to late maturity in spring barley for early sowing, in order to utilize more of the growing season, and resistance to loose smut [Ustilago
nuda (Jens.) Rostr.] are examples of specific characteristics that may be
used in varietal decisions. Second, the variety must have the potential as
a suitable raw material for malt. The various agricultural experiment stations in states with malting barley breeding programs collaborate with the
malting and brewing industry through the Malting Barley Improvement
Association in the evaluation of potential malting barley varieties. Acceptable malting barley varieties are made known to growers through publications listing the varieties available for production or, in some states, the
G. A. PETERSON AND A. E. FOSTER
recommended malting barley varieties. However, growing of an acceptable
malting variety does not assure the production of acceptable grain. Standards for kernel protein percentage, kernel plumpness, percentage of skinned and broken kernels, kernel discoloration, and other factors must be
B. SEED QUALITYAND TREATMENT
Numerous investigators with several crops have dealt with the effect of
seed quality on grain yield and the components of yield as well as on other
agronomic characteristics. Although barley is considered a superior competitor against weeds, compared to other small grain cereals and flax, seed
of high germination, good plumpness or weight, and freedom from weed
seeds, diseases, and inert mixtures is recommended to produce optimum
plant stands as measured by seedling emergence and vigor.
Kaufmann and McFadden (1963) and Peterson and Foster (1964)
found seed size to be associated positively with grain yield, especially under
conditions of plant stress often experienced with late sowing. The number
of spike-bearing tillers was the yield component most affected by seed
size. The barley plant appears to compensate for seed and seedling deficiencies during the growing season if the environment is favorable for barley grain production. Seed quality factors are important to malting barley
in the way that they affect kernel size or plumpness of the resultant crop
in addition to the usual criteria of agronomic performance. Kernel plumpness of harvested grain has been shown to be maintained at a higher level
when plump seed is used for late planting (Peterson and Foster, 1964).
The use of chemical seed treatment is a recommended malting barley
production practice found to be effective in controlling certain seed-borne
diseases (Dickson, 1962; Reid et al., 1968). Also, protection of germinating seeds and young seedlings against harmful organisms in the soil is obtained. Seed treatment is more likely to prevent losses from diseases which
weaken plants or prevent spikes from producing seed than to prevent losses
from diseases which reduce or impair quality of the harvested grain. Kernel
plumpness and protein percentage can be influenced by diseases if interplant competition is altered or nonthrifty plants contribute to the total production. Recommendations of state agricultural experiment stations should
be followed closely in the use of seed treatments on malting barley.
The best soils for growing malting barley are well-drained loams and
clay loams (Harlan and Wiebe, 1943; Reid et al., 1968). Barley is more
MALTING BARLEY IN THE UNITED STATES
susceptible to damage than several other crops from water-saturated soil.
Light, sandy soils in the subhumid and semi-arid regions often produced
drought stress of plants, resulting in low yields. The fertility level of the
soil is extremely important for malting barley and will be discussed in a
Most of the malting barley in the United States is spring sown. Most
of the spring barley is sown on land which was cropped the preceding
year. A common practice is to fall plow, especially fine-textured soils of
the Red River Valley of North Dakota and Minnesota or where winter
erosion is not a problem. Seedbed preparation of fall-plowed land involves
shallow tillage in the spring to control weeds, to prevent deeply buried
weed seeds from being brought to the surface, and to reduce soil moisture
loss. Disking or field cultivating followed by a harrowing often is used in
the spring on land previously seeded to a row crop. In less humid areas
where malting barley is grown on previously cropped land, the most common practice is to spring plow or to use other implements which leave
some of the crop residue on the surface. Spring soil moisture often is more
favorable with spring than with fall tillage because of snow cover held during the winter. Also, the standing crop residue reduces erosion during the
winter. Under irrigated conditions, as used for malting barley in many
western areas of the United States, the land is preferably plowed.
Some spring-sown malting barley is planted on summerfallow. Generally, this is not a recommended practice because protein content of the
grain produced may be too high. However, some summerfallow fields may
not have excessive soil nitrogen levels (Wagner et al., 1970) and are suitable for malting barley production. Shallow tillage for seedbed preparation
is recommended for land which has been summerfallowed.
Fall-sown winter or spring malting barleys usually are shown on nonfallow land. Plowing followed by various tillage operations to prepare a firm,
level seedbed often is used if large crop residues exist. If crop residues
are of minor consequence, seedbed preparation is similar to that mentioned
for spring-sown barley on row-crop land. A small amount of fall-sown
malting barley is seeded on summerfallow and seedbed preparation is similar to that for spring-sown barley.
Malting barley usually is grown in a crop sequence. The kind of sequence varies with the other crops adapted to the region, length of growing
season, availability of moisture, soil type, soil fertility, and disease problems (Reid et al., 1968). Barley following barley is not a recommended
cropping practice, particularly in areas where inoculum of destructive diseases can build up on residues in the soil and on the surface. Barley following corn or wheat is undesirable in areas where scab is a problem unless
clean cultivation and sanitation are practiced. In the more humid regions
G. A. PETERSON AND A. E. FOSTER
where summerfallowing is not practiced, malting barley production following row crops such as sugar beets, potatoes, and sunflowers has been successful if soil nitrogen levels are not excessive. Occasionally malting barley
is used as a companion crop with a legume or legume-grass mixture in
these areas or where irrigation is used. Malting barley follows wheat in
many rotations in the major producing areas of the North Central States.
Fallow-wheat-barley is a common crop sequence for less humid malting
barley growing areas.
Malting barley usually is seeded with a grain drill, often equipped with
press wheels and a fertilizer attachment (Reid et al., 1968). Most drills
have disk furrow openers which place the seeds in rows 6-8 inches apart.
Hoe drills, with about 9 inches between rows, are used in some areas of
the Pacific Northwest on clean fallowed land, and in some of the less
humid regions of the upper Midwest.
The desired plant population for a specific set of environmental conditions is obtained by selecting an appropriate rate of seeding. Variety, date
of sowing, soil moisture, and conditions affecting seedling emergence are
the most important factors affecting the number of spike-bearing tillers
per unit area. Varieties with large seeds and low tillering capacity require
higher seeding rates. A delay in date of seeding, which often reduces tillering or stand reductions due to poor seedling emergence in nonfriable soils,
also dictates use of higher seeding rates to compensate for below optimum
stands. Lower rates of seeding ordinarily are used in drier areas because
less dense stands reduce stress due to interplant competition. Competition
from excess weed growth requires that barley be seeded at higher rates
than normal (Woodward, 1956).
Grain drills meter out the barley seed by volume, and seeding rate recommendations normally are made on this basis. Planting 1.5 to 2 bushels
of barley per acre is a general practice in the more humid area of the
North Central States and in irrigated regions of Western United States.
One to 1.5 bushels are seeded in the less humid malting barley growing
areas of the Midwest. Seeding by volume is one reason the grower adjusts
seeding rate by variety or kernel size. Berdahl (1967) was not able to
show any difference in grain yield when rates from 0.75 bu/acre to 1.75
bu/acre were seeded in North Dakota by volume, weight, or number of
seeds per unit area. These results, along with an increase in the number
of spike-bearing tillers with the use of large seed (Kaufmann and McFadden, 1963; Peterson and Foster, 1964), indicate the compensation in rate
of seeding may be less important than growers believe. Studies with barley
show that similar grain yields are obtained over a wide range of seeding
MALTING BARLEY IN THE UNITED STATES
rates (Meredith and Olson, 1942; Woodward, 1956; Berdahl, 1967). An
important factor to the malting barley grower, however, is that the range
of seeding rate for the production of quality grain is more critical than
for quantity. Higher seeding rates than required for optimum stands reduce
kernel size (Meredith and Olson, 1942; Woodward, 1956; Peterson,
Date of seeding of malting barley is influenced by latitude, altitude, climatic conditions, cropping practices, and use of spring or winter varieties
(Reid et al., 1968). Most of the malting barley for processing by the malting industry is obtained from spring-sown barleys. The general recommendation for these production areas is that seeding should begin as soon as
a good seedbed can be prepared. In the North Central States the earliest
seeding date ranges from about March 10 to May 10. The range of preferred dates of seeding spring barley in the Pacific Northwest and intermountain areas is from March 15 to April 30. Some winter barley is sown
in these areas from September 1 to October 15. In California, spring varieties are sown from late October to mid-January.
The benefits of early spring seeding regarding performance for yield and
other agronomic characteristics have been established by numerous investigators (Woodward, 1956; Beard, 1961; Jackson et al., 1962; Peterson,
1966; Berdahl, 1967; Hoag and Geiszler, 1968; Zubriski et al., 1970).
Seeding date is among the most important factors involved with malting
barley production. Although grain yield response to seeding date may differ
with varieties (Beard, 1961; Berdahl, 1967) or with years or locations
(Woodward, 1956; Zubriski et al., 1970), the advantage of early seeding
of barley is affirmed. Reduction in grain yield with delayed seeding appears
to have a linear trend in some studies and nonlinear in others. A delay
of one month from the optimum seeding date for malting barley in North
Dakota resulted in grain yield reductions of 53% (Peterson, 1966), 22%
(Berdahl, 1967), and 7% (Hoag and Geiszler, 1968). Most studies show
yield losses to be within the range of the North Dakota studies, with the
position within the range depending on the variety and/or the environment
under which the trials were conducted.
The effect of date of seeding on characteristics of harvested grain is important to the grower since the influence on grade and suitability for malting have a direct impact on economic return. In addition to a loss in yield,
losses in kernel weight, kernel plumpness, and test weight per bushel appear
to be some of the most consistent effects indicated in date of sowing studies
(Meredith and Olson, 1942; Woodward, 1956; Beard, 1961; Jackson et
al., 1962; Peterson, 1966; Berdahl, 1967; Hoag and Geiszler, 1968;
Zubriski et al., 1970). Kernel protein percentage increases with late seeding (Meredith and Olson, 1942; Hoag and Geiszler, 1968; Zubriski et al.,
G. A. PETERSON AND A. E. FOSTER
1970) and levels are often in excess of those suitable for malting (Table
VIII), Undesirable decreases in barley extract (Beard, 1961) and malt
extract (Meredith and Olson, 1942) were found as a result of late seeding.
Expected increases in diastatic power in the barley grain accompanying
the increase in kernel protein levels were found by Beard (1961).
Influence of Seeding Dates and Rates of Nitrogen and Potassium Fertilizers
on Average Grain Yields, Percentage Plump Kernels, and Protein Content of Graina
N or K
Average plump kernels
Adapted from Zubriski et al. (1970).
Barley should be sown at a depth at which moisture is available, but
the depth should not be so great that the energy requirement for emergence
exceeds the supply available in the barley kernel. In general, the depth of
seeding is 1-2 inches in the more humid malting barley growing areas and
2-3 inches in the drier regions.
One of the most important management decisions for the malting barley
producer is the amount of fertilizer to apply to the soil. High yields of
good quality grain is the goal of the barley grower. Protein content and
kernel plumpness are two properties of the harvested grain used to evaluate
malting quality and must be at desirable levels if the barley is to be purchased by the malting industry. These properties are greatly influenced by
the supply of available nutrients, particularly nitrogen, in the soil in relation to the minimum amount required for dry matter production. Other
MALTING BARLEY IN THE UNITED STATES
variables affecting grain quality are the barley variety, moisture, and temperature conditions under which the variety is produced, and diseases or
other pests detrimental to favorable plant growth.
The close relationship of soil nitrogen levels to yield and protein content
of the grain has been recognized for a long time. Hopkins (1936), Jackson
et al. (1962), Zubriski el al. (1970), and Bishop and MacEachern (1971)
found nitrogen fertilizer increased average grain yields on nitrogen-deficient soils. Protein content of the grain increased significantly when excessive nitrogen fertilizer was used. Protein content of the grain appears to
increase to the greatest extent after the maximum grain yield level is
reached. When the yield curve begins to level off as greater amounts of
nitrogen (are made available, protein content of the barley grain increases
rapidly. If the nitrogen available to the plant exceeds that required for
optimum yield in relation to the other soil nutrients and environments,
kernel protein levels above those desirable for malting barley often result.
Nitrogen fertilization appears to influence kernel plumpness or size less
than grain yield or protein. Kernel plumpness and size are most seriously
reduced if use of fertilizer or other factors induce lodging at a relatively
early growth stage. Grain yield and kernel protein responses in barley with
the addition of different levels of nitrogen fertilizer show considerable variability as reported by many workers. Also, significant interactions with
years, locations, and varieties have been indicated (Olson et al., 1942;
Frey et al., 1952; Pendleton el al., 1953; Zubriski et al., 1970). The discrepancies in response to different amounts of nitrogen fertilizer indicated
among the various reports probably result from not considering the amount
of nitrogen in the soil profile available to the barley plant before fertilizer
application and from uncontrolled environmental variables. Soper and
Huang (1962) showed a highly significant correlation of 0.95 between
nitrate nitrogen in the soil to a 4-fOOt depth and yield response to nitrogen.
Also, the correlation between uptake of nitrogen in the grain and nitrate
nitrogen in the soil profile plus nitrogen added at seeding time was
r = 0.90.
The need for a certain amount of nitrogen fertilizer to enhance malting
barley production on land which has been cropped previously is well
understood. Many producers have thought summerfallow to be unsuitable
for growing malting barley because of suspected high levels of nitrate-nitrogen in the soil which would lead to higher levels of protein in the grain
produced. Recent summaries show that about 15% of the summerfallowed
fields in the Red River Valley of North Dakota and Minnesota and adjacent areas contain less than 100 pounds/acre of nitrate nitrogen (Wagner
et al., 1970). Acceptable malting barley can be produced on these summerfallow fields. Producers utilizing the NO, soil test to predict the amount
G. A. PETERSON AND A. E. FOSTER
of nitrogen available for crop growth can make reliable decisions on choice
of land to use for malting barley and how much nitrogen, if any, to apply.
Malting barley has shown favorable responses to phosphorus and potassium applied to soils in which these elements are deficient. Grain yield
increases, reduced lodging, increased kernel plumpness, and reduced protein content of grain are the major benefits attributed to applications of
phosphorus (Hopkins, 1936; Norum et al., 1953; Pendleton et al., 1953;
Atkins et al., 1955). Response of barley to phosphorus fertilizer often is
observed on both fallow and nonfallow land. The use of potassium fertilizer on malting barley has given less consistent responses than nitrogen
or phosphorus with agronomic and quality characteristics (Hopkins, 1936;
Pendleton et al., 1953; Bauer and Vasey, 1964; Zubriski et al., 1970).
An increase in percent of plump kernels and often an accompanying decrease in kernel protein content by application of potassium fertilizer are
among the more frequent favorable responses observed.
The use of nitrogen, phosphorus, and potassium fertilizers on malting
barley should be based on soil test results along with other production variables, such as soil moisture, soil type, and date of seeding. Fertilizer recommendations for malting barley, made by state agricultural experiment stations such as those presented by Wagner et al. ( 1970), consider the several
variables in suggesting the levels to be applied. The need for a balanced
level of nutrients available to the barley plant for best grain quality has
been recognized (Hopkins, 1936; Pendleton et al., 1953; Jackson et al.,
1962; Zubriski et al., 1970; Bishop and MacEachern, 1971). Most soils
used for malting barley production appear to have satisfactory levels of
A large array of pests can influence malting barley production and the
quality of harvested grain. The effects can be either through competition
with the barley plant, as with weeds, or by direct attacks on different parts
of the plant by diseases or insects. The loss or damage is a result of an
interaction between the barley genotype and pest as influenced by the environment. Control of any pest may be accomplished through the use of
one or a combination of practices which include cultural methods, sanitation, chemical treatments, resistant varieties, or timing of management
operations. A lengthy discussion on pests of malting barley will not be
included because of the number and variability of effects. Some known
effects of pests on malting barley are grain yield reductions, decreased kernel size and weight, discoloration and blighting of the grain, increased kernel protein, and changes in chemical constituents of the kernel. Reviews
of pests and their control in barley include those for weeds (Reid et al.,
MALTING BARLEY IN THE UNITED STATES
1968), insects (Reid et al., 1968), and diseases (Dickson, 1962; Reid
et al., 1968).
The primary method of harvesting and threshing malting barley in the
major producing areas in the North Central region of the United States
is windrowing followed by combine threshing of the windrows. Cutting
and direct threshing of the standing grain, termed direct or straight combining, is a common practice in Western United States.
Windrowing has two main advantages. First, shattering is avoided since
considerable moisture is contained in the straw and grain at the time of
windrowing. This feature especially is applicable to the midwestern grown
six-rowed Manchurian types because of their tendency to shatter at maturity. Second, weed mixtures and barley of uneven maturity are permitted
to dry enough to allow proper threshing and usually reach a kernel moisture content adequate for safe storage. Several workers (Harlan, 1920;
Harlan and Pope, 1923; Dodds and Dew, 1958; Koenig et al., 1965;
Brewer and Poehlman, 1968; Pomeranz et al., 1971) have shown that
the deposits of dry matter in the barley kernel cease as the kernel moisture
content reaches the 3 5 4 2 % level. The barley kernel is termed physiologically mature when the addition of dry matter to the grain ceases. Changes
from the 35-42% level of kernel moisture to maturity have been considered to be primarily dehydration. Grain yield and kernel weight are not
reduced by windrowing of malting barley at physiologic maturity with subsequent threshing when the grain has a moisture content of 15% or less.
Windrowing at high levels of kernel moisture has affected the variability
of chemical characteristics used to measure quality of malting barley more
than it has affected the variability of grain yield and kernel weight. Optimal
properties for some of the chemical characteristics appear to be reached
when the barley is windrowed or harvested at kernel moisture contents
below 3 5 4 2 % . Malt modification, as measured by fine-coarse extract
difference, a-amylase activity, and protein solubility (expressed as the wort
nitrogen-to-malt nitrogen ratio) are factors that benefit from barley maturation. Windrowing when the kernel moisture ranges from 18 to 35% appears suitable in order to obtain desirable chemical properties in the grain
for malting barley (Dew and Bendelow, 1963; Koenig et al., 1965;
Pomeranz et al., 1971).
The moisture content of barley grain when threshed is important to
malting quality. Watson et al. (1962) found that with direct combining,
germination was reduced below an acceptable level for malting barley if
the moisture content was above 21.5%. Although other malting quality
characteristics were satisfactory in grain with higher moisture content, me-
G. A. PETERSON AND A. E . FOSTER
chanical damage was responsible for poor germination at these levels.
Malting barley should not be threshed if the moisture content is above
Threshing malting barley is a critical operation for the producer because
acceptable grain can be made unsuitable for malting by improper threshing. The principal factor which causes reduction in, or the elimination
from, the malting barley grades is skinned and broken kernels. Excessive
cylinder speeds of the combine mainly are responsible for skinned and
broken kernels (Vogel, 1958). Concave clearance of the combine should
be adjusted in relation to correct cylinder speed to properly thresh without
excessive damage to the grain (Kucera, 1972). Sieves and air should be
adjusted for minimum tailings in the return to prevent kernel damage
caused by barley passing through the cylinder a second time. Kernel damage from threshing is greatest when moisture content is too low or high.
The moisture content of the grain varies with the time of day, and therefore, combine adjustments should be made according to prevailing
Most malting barley is stored in bulk in bins of various sizes. Grain
elevators are used in transferring the barley into and out of these bins.
If a blower type of elevator is used, excessive fan speeds should be avoided
to prevent skinned or broken kernels (Vogel, 1958). For safe storage of
malting barley for long periods, kernel moisture content should be less
than 13% (Tuite and Christensen, 1955). Grain should be dried to a
moisture content of 13% or less to prevent heating and possible deterioration in malting quality characteristics, especially loss of germination. Barley
intended for malting purposes should be harvested at a kernel moisture
content of 20% or lower and not be subjected to drying air temperatures
above 130°F (Watson et al., 1962). Lower drying air temperatures should
be used as kernel moisture levels increase. High air velocity and temperature are being used in some of the new drying units, and extreme care
should be exercised in use of this equipment on malting barley to prevent
loss of quality.
In the post-ripening process that takes place in newly threshed and stored
barley, the moisture and temperature tend to increase. If the moisture content is above 13 %, molds develop and temperatures continue to rise and
cause the grain to deteriorate. Tuite and Christensen (1955) found that
storage molds became active when kernel moisture content was above
13 % , resulting in decreased germination. The storage molds were the main
cause of germination loss since mold-free grain retained viability when
stored for 15-30 days at room temperature and at moisture contents up
MALTING BARLEY IN THE UNITED STATES
to 19.4%. Invasion of the kernels by the storage molds, Aspergillus spp.
and Penicillium spp., took place after harvest. Fungi such as Alternuria
spp., Cladosporium spp., and Fusarium spp. are sometimes abundant in
the pericarp of the kernels and under the hulls before maturity, but decrease after barley is placed in storage. These fungi are associated with
kernel discoloration and blight in harvested grain. Dickson (1962) made
an extensive review of the kernel diseases of barley and their effect on
Barley infested with insects or rodents will deteriorate in storage and
may become “unfit for human use,” thus not classifying as malting barley
in the marketplace. Sanitation and use of recommended chemicals on storage facilities before use can help alleviate these problems.
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