JOURNAL OF THE SCIENTIFIC AGRICULTURAL SOCIETY OF FINLAND

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Maataloustieteellinen Aikakauskirja
Voi. 51:40-50, 1979

On the DBC protein content and on the amino acid
contents in F 5 lines of the barley line Hiproly

Marketta Saastamoinen
Department of Plant Breeding, University of Helsinki, 00710 Helsinki 71

Abstract Two descendant groups of the barley line Hiproly and the parents, Hja
c2661 and Hja c4003, were examined for variations in the DBC protein and amino acid
contents. The frequency distributions of the DBC protein content in both descendant
groups were unimodal and no effect of one gene was seen, even though the high lysine
content of Hiproly is caused by one gene (lys). The means of the DBC protein contents
in these Fg generations were 19.1 % and 19.0 %.

Environmental factors have a great effect on the DBC protein content: environ-
mental variances from the total variances were 93.84 % and 41.54 %. In the lines with
the highest DBC protein contents there were generally more basic amino acids, phenyla-
lanine and proline, than in the lines with the lowest DBC protein contents. Therefore, it
appears that the lines with the highest DBC protein contents contain much albumins and
prolamins. Also, the ratios of basic amino acids to proline indicated that the relationships
between albumins and prolamins were nearly the same for all the lines. Thus, the high
DBC protein content in many lines is really based on high amounts of albumins and
prolamins at the same time. The present study indicated that Hiproly may be better
than the Riso 1508 mutant of barley in breeding for the yielding capacity, because the
lys gene of Hiproly does not seem to decrease the prolamin content.

1. Introduction

Although cereals are very important for protein production, the protein
is not of high quality because some amino acids are not present in sufficient
quantities. Most notable is the small amount of lysine, but also methionine
and threonine exist in low amounts in the seed protein of most cereal plants.
Hagberg and Karlsson (1969), when screening over one thousand barley
lines (Hordeum vulgare L.), found one barley line Hiproly, which had a high
protein and lysine content. The high lysine content of this Ethiopian barley
line Hiproly is dependent on a single recessive major gene (lys) and several
minor genes (Munck et al. 1970, Karlsson 1972, Karlsson 1976). Hagberg

and Karlsson (1969) found the barley line Hiproly by a DEC method,
which is based on the dye binding capacity of basic amino acids (lysine, arginine
and histidine) and the free amino ends of polypeptide chains. Thus high
lysine and high protein lines are screened from other lines (Mossberg 1969).

https://www.c-info.fi/en/info/?token=gLyLYu_ZGleXg8XW.bavsFCHNmUfPxbVSVIw09g.PT0ETSUV6Zaf9tQW5DM_QDQpii49_S4t75Lpp-zb1s3-Oqps306WmwtQVBHCxz3fh3A5xzQwho2TmZ44HaXz97Yigyx-GYdhVlppbLTpRa3OCLVtjT348nMdpmtBcmsL_jJRcu_otcpNbpAufzQhpPpFMVUPhdhWYrEAb3hqvGp7V1Q


41

Munck et al. (1970) were able to distinguish in the F 2 generation of the barley
line Hiproly two differing groups: the lines which have a high DBC value and
a high lysine content and the lines which have a low DBC value and a low
lysine content.

The present study investigates the variation in DBC protein and amino
acid contents in the F 5 lines of the barley line Hiproly. It has also been possible
to study the inheritance of the DBC protein content and the factors on which
it depends. The present work is based on a project concerning the breeding of
high quality barley varieties at the Hankkija Plant Breeding Institute. Material
for the study was obtained from this Institute.

2. Material and methods

2.1. Materiat

The material was the harvest of the year 1971. It consisted of the F 5
lines of two crossings: Hja c2661 x Hiproly and Hja c4003 x Hiproly, and the
parental lines Hja c2661 and Hja c4003. The lines Hja c2661 and c4003 had
grown on every tenth plot among the corresponding hybrid lines. Of the F 5
lines there were no repetitions on the field. Fertilization was 75 kg/ha N, 44
kg/ha P and 63 kg/ha K (Rekunen, personal communication). The following
varieties and lines of barley were also used as material: cv. Birgitta, cv. Ingrid,
cv. Karri, cv. Mari, cv. Mona and Hja c4109.

The hybrid segregants were taken as lines in the F 3 generation. Selection
against some morphological features was made (Rekunen, personal commu-
nication). It was not possible to get seeds from all lines. From the cross Hja
c2661 x Hiproly there were, in this study, 76 lines or 46.7 % of all F 5 lines of
this crossing. From the cross Hja c4003 x Hiproly there were, in this study,
243 lines which was 85.9 % of all F 6 lines.

The barley line Hiproly is a 2-row naked barley with a high protein content
(17 %) and a high lysine content (4.1 g lysine/100 g protein) (Hagberg and
Karlsson 1969). The line Hja c2661 is a 6-row fodder barley, which descends
from the crossing cv. Otra x cv. Paavo. The line Hja c4003 is a 2-row barley,
which was obtained by radiating the line Hja b7990. The line Hja b7990 is
descended from the crossing (cv. Louhi x cv. Opal) x cv. Stallar II (Rekunen,
personal communication).

2. 2. Determination of DBC protein and amino acid contents
The DBC protein content was analysed by a Pro-Meter Mk II machine

(prepared in A/S N. FOSS ELECTRIC, DK 3400 Hillerod, Denmark). Its
function is based on the UDYs (1956) method. The machine records the values
of proteins as per cent from the sample. Because the DBC protein contents
of most lines were more than 17 % (the maximum value which the machine
records), samples of 400 mg were used as against samples of 500 mg according
to the operation instructions. From three to five repetitions were made from
every sample. The water contents of the samples were determined according



42

to Conger et al. (1970). The following abbreviation is used: DBCpc = the
DBC protein content.

Amino acid analyses were made for 12 lines of Hja c4003 x Hiproly. These
were the six lines with the highest and the lowest DBC protein contents. An
acid hydrolysis was made at first for 40 mg samples in which tryptophane is
destroyed (Kohler and Palter 1967). After that the samples were driven
by a Hitachi Perkin-Elmer liquid chromatography and a Ligandi method was
used (Eaker 1968).

2. 3. Statistical calculation
Because most samples used to determine the DBC protein content were

400 mg, the values had to be modified to correspond to samples 500 mg in
size. For this purpose, a regression model was developed from which it was
possible to determine the DBC protein contents in samples of 500 mg as well
as in samples of 400 mg. The regression equation was developed by repetitions
of the samples of 400 mg (x-variable) and by repetitions of the samples of
500 mg (y-variable). With this regression equation it was possible to estimate
the values corresponding to the samples of 500 mg, by using the values derived
from the samples of 400 mg. In this equation (y =bx a), xis the value
which was determined from a sample of 400 mg, and y corresponds to the value
of a sample of 500 mg. b is a regression coefficient and a is a constant.

Differences in the DBC protein content between the crossings and between
the lines were tested by the hierarchal analysis of variance (Kempthorne
1969). This calculation was performed in the Computer Centre of the University
of Helsinki. Percentages for the components of variance, such as line, cross and
repetition, were also calculated.

The environmental and genetic influence on the DBC protein content was
estimated according to Falconer (1967), assuming that the variance of the
parental line is an estimate of the environmental variance, and that the variance
of descendant lines is an estimate of the total variance.

The percentage content of each amino acid was determined by presuming
that there were proportionally the same amounts of tryptophane in each line.
The ratio of basic amino acids to proline was calculated for each line (Favret
et al. 1970) to indicate the proportional amounts of albumins and prolamins.

Otherwise the results were calculated statistically in the usual manner.

3. Results

The regression line in Figure 1 shows the relationship between the DBC
protein contents and the sample sizes. The correlation coefficient between
these values is 0.999***. This method was reliable because the standard error
of the estimate of y on x is 0.114. The standard error of the regression coef-
ficient b is 0.008, and the standard error of the constant a is 0.094.

The frequency distributions of the DBC protein contents of the lines in
two crossings do not indicate any clear differences between the crossings (see
Fig. 2). The lines differ from each other when analysed by the hierarchal



Fig. 1. A regression line between two sizes of samples.

Fig. 2. The frequency distributions of F 6 lines.
= F 5 lines of Hja c2661 x Hiproly.
= F 6 lines of Hja c4003 x Hiproly.



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analysis of variance (F = 3.678***), but between the crossings there is no
statistically significant difference. The component of variance caused by
variation between the lines is 99.37 % from the total variance. The component
of variance caused by crossings is 0 % and the component of variance caused
by the variation within the lines is 0.63 % from the total variance.

The means of the DBC protein contents in descendant groups are higher
than in the parents (see Table 1). The descendant group of Hja c2661 x Hiproly
differs from the parental line with respect to the DBC protein content determined
bv the analysis of variance (F = 20.220***). In the same way the descendant
group of Hja c4003 x Hiproly differs from the line Hja c4003 (F = 23.789***).
Between the parental lines there is no statistically significant difference.
Environmental factors have greatly influenced the DBC protein content
(see Table 1).

Table 1. Means, variances and the components of variance of the DBC protein contents in
two experimental groups.

Experimental
group

x s 2 Components of variance
total environ- genetic
variance, mental variance

variance,
Vp , % Ve, % vg , %

Hja c2661 x
Hiproly: 100.0093.84 6.16
Hja c2661 16.74.10
F 6 generation
of Hja c2661 x 19.14.37
Hiproly

Hja c4003 x

Hiproly: 100.0041.54 58.46
Hja c4003 17.51.59
F 6 generation
of Hja c4003 x 19.03.82
Hiproly

There are differences in some amino acid contents between lines which have
high or low DBC protein contents (see Table 2). The lysine contents of protein
in the lines with high DBC protein content are 3.54 %. 3.60 %, 3.66 %, 3.89 %,

4.06 % and 4.21 %. The correlation coefficients between the amino acid
contents and the DBC protein contents are different (see Table 2). The ratio
of the amount of basic amino acids to the amount of proline is nearly the same
for every line (see Table 3). There is no statistically significant difference
in these relationships between the groups of lines which have the highest
or the lowest DBC protein contents.



Table 2. The relative (%) amino acid contents in different groups and the correlation
coefficients between the amino acid contents and the DBC protein contents.

Amino Group 1. low DBCpc Group 2. high DBCpc F-test r
acids n = 6 n = 6 between

x s x s groups

Asp 5.410.70 5.432.27 - +O.Ol
Glu 27.911.52 26.191.55 - -0.51
Thr 3.380.13 3.300.08 -0.35
Ser 3.90 0,19 3.930.19 - +O.ll
GluN - - - - - -

Pro 11.140.62 12.310.84 * +0.64*
Ala 4.250.11 4.330.29 - +0.19
Gly 3.980.28 3.840.21 -0.26
Vai 5.580.22 5.540.28 -0.06
Cys 1.190.26 0.970.23 - -0.42
Het 1.440.07 1.500.17 - +0.28
Ileu 4.330.26 4.390.08 - +0.19
Leu 8.420.56 8.090.35 -0.35
Tyr 3.120.15 3.370.17 * +0.68*
Phe 5.480.18 5.750.20 • +0.63*
Lys 3.430.15 3.840.28 ** +o.7l**
His 2.120.15 2.180.07 - +0.33
Try - - - -

Arg 4.180.18 4.710.26 ** +o.7B**
Lys +

His +

Arg 9.730.40 10.730.55 ** +o.7s**

Significance: nonsignificant, *P < 0.05, **P < 0.01.

Table 3. The phenylalanine, lysine and proline contents and the amounts of basic amino
acids (jMg basic amino acids/g meal) per the amount of proline [/ ig proline/g meal) relationships
for different lines.

The amount of
Line Type of the % phenylalanine % lysine % proline basic amino

line acids/the amount
of proline

1. low DBCpc 5.32 3.36 11.66 0.818
2. low DBCpc 5.57 3.40 11.22 0.872
3. low DBCpc 5.41 3.19 10.14 0.890
4. low DBCpc 5.27 3.52 11.91 0.844
5. low DBCpc 5.59 3.55 11.02 0.903
6. low DBCpc 5.74 3.58 10,91 0.920
7. high DBCpc 6.03 3.54 11.79 0.866
8. high DBCpc 5.86 3.66 12.57 0.825
9. high DBCpc 5.47 3.98 12.69 0.854

10. high DBCpc 5.56 3.60 12.11 0.848
11. high DBCpc 5.82 4.21 11.13 1.044
12. high DBCpc 5.75 4.06 13.59 0.815

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46

4. Discussion

The frequency distributions of the DBC protein contents in the descendant
groups are unimodal. The distribution of the lys gene ought to be 3 : 2 : 3 in
these descendent groups, because the descendants have been taken as lines in
the F 3 generation and because barley is highly inbreeding. From the lines 6/8
ought to be homozygotic for this locus. The lys gene increases the lysine
content by 30 % compared to typical commercial varieties (Munck et al. 1971).
In the lines which have the highest DBC protein contents there must be much
protein and/or much basic amino asids, because the function of the Pro-Meter
Mk II is based on the dye binding capacity. The effect of the lys gene is so
great that the frequency distributions ought to be bimodal. Selection in the
descendant groups has possibly been able to change the distributions. Olsen
(1974) has also found unimodal distribution of the DBC protein content in the
F 3 generation of the barley line Hiproly and he has not been able to see any
effect of one gene in that distribution.

The correlation coefficient (r = 0.71) between the DBC protein content
and the lysine content is low compared to the correlation coefficient (r = 0.93)
between the lysine content and the amount of bound dye obtained by Hag-

berg and Karlsson (1969). The mean lysine content (x = 3.84 %) in the
lines which have the highest DBC protein contents is only slightly higher than
the mean lysine content (x= 3.44 %) in the lines which have the lowest
DBC protein contents. This explains the unimodality of the frequency dis-
tributions.

The lysine content of protein was estimated to be over 4 % in two barley
lines and nearly 4 % in one barley line. In the barley line Hiproly and in the
hybrid lines, which have been homozygotic for the lys gene, there has always
been lysine more than 3.9 % and nearly always over 4 %, while in usual com-
merical barley varieties and in not hily (high lysine) segregants of the line
Hiproly there has been 3.25—3.90 % lysine depending on the protein content
(Munck et al. 1969, Hagberg et al. 1970, Munck 1970, Munck et al. 1970,
Munck et al. 1971, Munck 1972 a, Munck 1972 b). Obviously only those
lines in which the lysine content is over 4 % can be homozygotic for the lys
gene. However, the lysine content of every line with a high DBC protein
content, is above average because there is usually a high negative correlation
between the lysine content and the protein content (Hagberg and Karlsson
1969). Evidently all lines which have the highest DBC protein content are
not homozygotic for the lys gene, but are mixtures consisting of many lines
homozygotic for the lys or wild allele at this locus.

The correlation coefficient between all basic amino acids (Arg -)- Lys +

His) and the DBC protein is higher than the correlation coefficient between
lysine and DBC protein. This is consistent with the result of Mossberg (I960).
The highest correlation coefficient is, however, between the arginine content
and the DBC protein content.

The DBC protein contents of the parent lines are also very high. N and P
fertilization may have brought about this result. It is apparent that environ-
mental factors have a great effect on the DBC protein content since there is a



47

great variation in the DBG protein content in the parental lines. There is more
phenylalanine in lines which have the highest DBG protein contents. This
means that there must be much prolamins in those lines (see Harris 1962).
This may be due to N fertilization, which increases the proportional amount of
prolamins in barley seed proteins (Andersen and Kgie 1975).

The amounts of basic amino acids proline relationships also indicate
that the relationships between albumins and prolamins are nearly the same
for all 12 lines. Favret et al. (1970) believe that this relationship expresses
the proportional amounts of these protein components. If the value is 1, the
relationship is normal, if it is >l, there are more albumins rich in lysine, and
if it is <l, there are more prolamins poor in lysine. In the lines which have
the highest contents of DBG protein, there must be much albumins and prolamins
present simultaneously.

The high phenylalanine and proline contents of the high DBG protein
lines in the present study indicate that the lys gene does not decrease the
prolamin content. Berdahl and Bhatty (1977) have found that Hiproly and
a normal lysine barley line and the high lysine plump segregants of Hiproly,
have the same prolamin content, but the shrunken segregants of Hiproly
have a slightly lower prolamin content than Hiproly. In contrast to Hiproly,
Riso 1508, the other high lysine mutant of barley (Doll 1973, Muench et al.
1976), has only one-third of the normal prolamin content (Ingversen et al.
1973).

The environmental influence on the protein content has proved very
considerable even in this one field experiment. This was also noted by Favret
et al. (1970), who considered the absolute amount of protein of one seed (N/
seed) to be more stable than the protein content, expressed as per cent from the
dry matter. Environmental factors affect the weight and volume of a seed.
Furthermore, the weight and the volume of a seed are negatively correlated
with the protein content, while the absolute values are less variable. When
proteins are expressed as per cent values from the dry matter, it is difficult
to find the amount of variation which is caused by genetic factors. A possi-
bility for decreasing the variation in the protein content caused by environ-
mental factors lies in the use of powerful N fertilization. Increased N fertiliza-
tion raises the protein content and simultaneously decreases variation in the
protein content caused by environmental factors. Thus the genetic variance of
the protein content increases in relation to the total variance (Ulonska et al.
1975). Selection studies performed under powerful N fertilization can of
course be criticized for economical reasons.

The greatest difficulty in breeding high lysine barley varieties lies in
maintaining the yielding capacity at a high enough level. It seems that inac-
tivation of prolamin synthesis impairs the accumulation of carbohydrates in the
endosperm (Doll 1977) thus lowering the yielding capacity. Hiproly can be
better than Riso 1508 in breeding for yielding capacity since it has a high
prolamin content. In Riso 1508 the high lysine content is the result of one
gene that blocks the synthesis of several protein bands with high molecular
weight in the prolamin fraction (Brandt 1976, Koie et al. 1976). In Hiproly
Ingversen and Koie (1971) have found an extra lysine rich band in the salt-
soluble protein fraction.



48

Acknowledgements. Dr. E. Kivi and Mr. M. Rekunen from the Hankkija Plant Breeding
Institute have kindly supplied me with the plant material for the study. Prof. P. M. A. Tigerstedt
gave me the opportunity to work at the Department of Plant Breeding and made valuable
suggestions during the work. Mrs. Silja Home, Civ. Eng., has performed the amino acid analyses
at Panimolaboratorio Oy. Miss Lorraine Carson, B. Sc., has corrected the language. I ac-
knowledge my gratitude to all these persons and research units.

REFERENCES:

Andersen, A. J. & Koie, B. 1975. N fertilization and yield response of high lysine and
normal barley. Agron. J. 67: 695 698.

Berdahl, J. D. & Bhatty, R. S. 1977. Protein fractions and lysine distribution in barley
lines derived from Hiproly. Can. J. Plant Sci. 57; 1135 1139.

Brandt, A, B. 1976. Endosperm protein formation during kernel development of wild type
and a high-lysine barley mutant. Cereal Chem. 53: 890 901.

Conger, B. V., Konzak, C. F. & Nilan, R. A. 1970. Methods of applying pre- and post-treat-
ments. In: Manual on Mutation Breeding, p. 48 52. Tech. Rep. No. 119, lAEA,
Vienna.

Doll, H. 1973. Inheritance of the high-lysine character of a barley mutant. Hereditas 74:
293-294.
1977. Storage proteins in cereals. In: Genetic Diversity in Plants, p. 337 347. Ed.
A. Mudammed, R. Aksel & R. C. von Borstel, Plenum Publishing Corporation, New
York.

Eaker, D. 1968. The determination of free and proteinbound amino acids. Symp. on Evalua-
tion of Novel Protein Products. Stockholm.

Falconer, D. S. 1967. Introduction to Quantitative Genetics. 365 p. New York.
Favret, E. A., Manghers, L., Solari, R., Avila, A & Monesiglio, J. C. 1970. Gene control

of protein production in cereal seeds. In: Improving Plant Protein by Nuclear Tech-
niques, Proc. Symp, Vienna, 1970, p. 87 96. lAEA, Vienna.

Hagberg, A. & Karlsson, K.-E. 1969. Breeding for high protein content and quality in
barley. In: New Approaches to Breeding for Improved Plant Protein, Proc. Panel
Röstänga, 1968, p. 17 21. lAEA, Vienna.
, Karlsson, K.-E. & Munck, L. 1970. Use of Hiproly in barley breeding. In: Im-
proving Plant Protein by Nuclear Techniques, Proc. Symp. Vienna, 1970, p. 121 132.
lAEA, Vienna.

Harris, G. 1962. The structural chemistry of barley and malt. In: Barley and Malt. p. 431
566. Ed. A. H. Cook, Oxford. (Ref. Munck, L. 1964.)

Ingversen, J. & Koie, B. 1971. Protein patterns of some high lysine barley lines. Hereditas
69: 319-323.
, Koie, B. & Doll, H. 1973. Induced seed protein mutant of barley. Experientia 29;
1151-1152.

Karlsson*, K.-E. 1972. Linkage studies on a gene for high lysine content in Hiproly barley.
Barley Genet. Newsl. 2: 34 36.
1976. Linkage studies on the lys-gene in relation to some marker genes and trans-
locations. In: Barley Genetics 111. Proc. 3th Int. Barley Genet. Symp. Garching,
1975, p. 536 541. (Ref. Persson, G. & Karlsson, K.-E. 1977).

Kempthorne, O. 1969. An Introduction to Genetic Statistics. 545 p. Ames, lowa.
Kohler, G. O. & Palter, R. 1967. Studies on methods for amino acid analysis of wheat

products. Cereal Chem. 44: 512 520.
Koie, 8., Ingversen, J., Andersen, A. J., Doll, H. & Eggum, B. O. 1976. Composition and

nutritional quality of barley protein. In: Evaluation of Seed Protein Alterations by
Mutation Breeding, Proc. 3th Res. Co-ord. Meet. Hahnenklee, 1975, p. 55 61. lAEA,
Vienna.



49

Mossberg, R. 1969. Evaluation of protein quality and quantity by dye-binding capacity;
a tool in plant breeding. In: New Approaches to Breeding for Improved Plant Protein,
Proc. Panel Röstänga, 1968, p. 151 160. lAEA, Vienna.

Monck, L. 1964. The variation of nutritional value in barley. I. Variety and nitrogen fertilizer
effects on chemical composition and laboratory feeding experiments, Hereditas 52:
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1970. Increasing the nutritional value in cereal protein. Basic research on hily character.
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319-329. lAEA, Vienna.
1972 a. High lysine barley a summary of the present research development in Sweden.
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1972 b. Improvement of nutritional value in cereals. Hereditas 72: 1 128.

, Karlsson, K.-E. & Hagberg, A. 1969. Bättre näringsvärde hos spannmälsprotein.
Sver. Utsädesför. Tidskr. 3—4: 196 205.
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, Karlsson, K.-E., Hagberg, A & Eggum, B. O. 1970. Gene for improved nutritional
value in barley seed protein. Science 168; 985 987.

Muench, S. R,, Lejeurne, A. J., Nilan, R. A. & Kleinhofs, A. 1976. Evidence for two
independent high lysine genes in barley. Crop Sci. 16; 283 285.

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287-302.

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Ms received January 10, 1979.

SELOSTUS

DBC-proteiinipitoisuudesta ja aminohappojen määristä Hiproly ohran F 3
linjoissa

Marketta Saastamoinen
Kasvinjalostustieteen laitos, Helsingin yliopisto, 00710 Helsinki 71

Tutkimusaineisto käsitti Hja c2661 x Hiproly ja Hja c4003 x Hiproly risteytyksen F 5
sukupolven linjat sekä kantavanhemmat Hja c2661 linjan ja Hja c4003 linjan. DBC-proteiini-
pitoisuus määritettiin Pro-Meter Mk II laitteistolla. Aminohappoanalyysi suoritettiin Hja
c4003 x Hiproly risteytyksen 12 linjalle: kuudelle DBC-proteiinipitoisuudeltaan korkeimmalle
ja alhaisimmalle linjalle.

DBC-proteiinipitoisuuksicn määrityksessä kehitettiin regressiomalli, jotta voitiin käyttää
normaalia pienempiä näytteitä, koska proteiinipitoisuudet olivat yleensä korkeampia kuin lait-
teiston maksimilukema. DBC-proteiinipitoisuuksien frekvenssijakautumat olivat F 5 suku-
polvissa yksihuippuiset, eikä niissä voitu havaita Hiproly ohran lys -geenin vaikutusta.

Hja c2661 x Hiproly risteytyksen jälkeläisten DBC-proteiinipitoisuuden keskiarvo oli
19.1 %, Hja c4003 x Hiproly risteytyksen jälkeläisten 19.0 %, Hja c2661 linjan 16.7 %ja



50

Hja c4003 linjan keskiarvo oli 17.5 %. Ympäristötekijöillä oli suuri vaikutus DBC-proteiini-
pitoisuuteen: ympäristötekijöiden aiheuttama varianssin komponentti kokonaisvarianssista
oli 93.84 % ja 41.54 % näissä kahdessa koeryhmässä.

DBC-proteiinipitoisuudeltaan korkeatasoisissa linjoissa oli enemmän proliinia, tyrosiinia,
fenylalaniinia, lysiiniä ja arginiinia kuin linjoissa, joiden DBC-proteiinipitoisuus oli alhainen.
Kahdessa linjassa oli lysiiniä yli 4 %, millä perusteella ne saattoivat olla lys -geenin suhteen
homotsygoottisia. Emäksisten aminohappojen määrä per proliinin määrä suhteet olivat kaikille
linjoille lähes samansuuruiset. DBC-proteiinipitoisuudeltaan eritasoisten linjojen välillä ei
ollut tässä suhteessa eroa. Korkeat DBC-proteiinipitoisuudet johtuivat aminohappoanalyysien
perusteella samanaikaisesta albumiinien ja prolamiinien korkeasta määrästä. Lys -geeni ei
alenna prolamiinien määrää. Tällä perusteella Hiproly ohra soveltuu paremmin kuin Riso
1508 mutantti korkeasatoisten ja korkeaa lysiinipitoisuutta olevien lajikkeiden jalostukseen.