Maataloustieteellinen A ikakauskirja Vol. 58: 151—156, 1986 The high-molecular-weight glutenin subunit compositions of wheat varieties bred in Finland TUULA SONTAG, HANNU SALOVAARA and PETER I PAYNE* Department of Food Chemistry and Technology, University of Helsinki, SF-00710 HELSINKI, Finland and * Plant Breeding Institute, Maris Lane, Cambridge CB2 2LQ, U.K. Abstract. The composition of high-molecular-weight (HMW) glutenin subunits in 35 Finnish bread wheat cultivars was determined by SDS-polyacrylamide gel electrophoresis. One third of the varieties have one of two HMW glutenin subunit compositions and there are only 17 different compositions in all. Three cultivars, Antti, Kiuru and Panu, are genetically mixed for some of these subunits. Cultivar Tammi (II) contains a novel HMW subunit of glutenin, not detected in any bread wheat previously analysed, and is presumed to be coded by genes on chromosome 1A at the Glu-Al locus. On the basis of previous work, which related indi- vidual subunits to bread-making quality, HMW glutenin subunit quality (Glu-1 quality) scores were calculated for the varieties. The results are related to the bread-making quality ofFinnish wheats. Index words: wheat, glutenin subunits, electrophoresis, quality Introduction The high-molecular-weight (HMW) sub- units of glutenin are synthesised in the devel- oping endosperm of wheat, which, at matur- ity, comprise some 10 % of the storage pro- tein of the grain. The subunits are coded by genes at three loci, Glu-Al Glu-BI and Glu- Dl, which occur on the long arms of chromo- somes IA, IB and ID respectively (Payne et al. 1982). Each locus exhibits extensive allelic variation (Lawrence and Shepherd, 1980) and this is partly responsible for the differ- ences in bread-making quality between culti- vars (Payne et al. 1981 a). The HMW sub- units of glutenin are best resolved by sodium dodecyl sulphate, polyacrylamide gel electro- phoresis (SDS-PAGE) and this is the estab- lished method of identifying and cataloguing the various subunits (Payne and Lawrence, 1983). The procedure can also be used in con- junction with aluminium lactate-PAGE, which fractionates the gliadin proteins, to identify cultivars and to determine which of them contain biotypes for storage proteins (Zillman and Bushuk 1979). 151 JOURNAL OF AGRICULTURAL SCIENCE IN FINLAND Table I. Finnish wheat cultivars, the name of the breeder, the pedigree and the year of cultivar release. Cultivar W/S Breeder Pedigree Year of cultivar release 1. Antti W Hja F, (01216 x Svea) x Ukrainka 1955 2. Aura W Jo Ertus x Vakka 1975 3. Elo W Hja Ta 07232 x Varma 1963 4. Ilves W Hja Hja b 356 x Vakka 1975 5. Jyvä W Jo Line from Vakka 1965 6. Linna W Hja Ta a 2701 x Virtus 1965 7. Nisu W Jo Line from Vakka 1966 8. Olympia W Jo From landrace (Uusimaa) 1941 9. Panu W Hja Svea x landrace (Loimaa) 1936 10. Pitko W Jo Ta 05901 x Vakka 1985 11. Pohjola W Jo From landrace (Uusimaa) 1933 12. Sampo W Jo Thule II x landrace 1933 13. Sukkula W Hja Line from landrace 1922 14. Sukkula II W Hja From Sukkula I 1928 15. Vakka W Jo Varma x Kehrä 1953 16. Varma W Hja Svea x landrace (Orimattila) 1933 17. Villa W Hja Line from landrace (Uusimaa) 192! 18. Apu S Jo Garnet x Pika 1949 19. Hopea S Jo Marquis x Ruskea 1936 20. Kimmo S Hja Line from Pisarev 2 1941 21. Kiuru S Jo Aurore x Sopu 1951 22. Luja S Jo Svenno x (Hopea x Tammi) 1981 23. Pika S Hja Ruskea x landrace (East Finland) 1927 24. Pika 11 S Hja Canadian landrace x Finnish landrace 1934 25. Ruskea S Hja Line from landrace (Holland) 1919 26. Ruso S Hja (Reward x Pika) x pollinator unknown 1967 27. Sopu S Jo Marquis x Ruskea 1935 28. Taava S Hja “Co mutant from Ruso 1978 29. Tähti S Jo Kärni x (Aurore x Pika) 1972 30. Tammi (II) S Hja Mclntosh xTa 01214 1938 31. Tapio S Hja Hja c 3929 x Kolibri 1980 32. Terä S Hja Hopea xTa 04609 1952 33. Touko S Jo Diamant x Hopea 1950 34. Ulla S Hja Tammi xTa a4431 1975 35. Veka S Hja Kärni x Tammi 1970 Abbreviations: Jo = Jokioinen, Agricultural Research Centre, Department of Plant Breeding Hja = Hankkija Plant Breeding Institute W = winter sown S = spring sown In this paper, we have used SDS-PAGE to determine the HMW glutenin subunit com- positions of the 35 spring and winter wheat cultivars bred inFinland over the last 60 years. The results are related to the bread-making qualities of the varieties. Materials and methods Samples of 35 winterand spring wheat cul- tivars were obtained from the Finnish State Seed Testing Station. The cultivars, the name of the breeder, the pedigree and the year of cultivar release are given in Table 1. SDS-PAGE Total protein was extracted from segments of three grains of each cultivar and fraction- ated by SDS-PAGE using 10 % gels as de- scribed previously (Payne et al. 1980 and 1982). All the cultivars were extracted and 152 analysed at least twice on separate gels. As described elsewhere (Payne et al. 1987) the presence or absence of subunit 2* cannot be determined for cultivars which contain sub- units 2+12 but lack subunit 1. Such cul- tivars were additionally analysed using 5 % gels (Payne et al. 1981 b) which clearly re- solves subunit 2 from 2*. The numbering sys- tem for the HMW glutenin subunits is that described by Payne and Lawrence (1983). Results A typical fractionation of cultivar grain proteins by SDS-PAGE is shown in Fig. 1. The area of the gel containing the HMW sub- units of glutenin is marked by brackets and they have been given numbers according to standardised nomenclature (Payne and Law- rence, 1983). All the subunits but one in the set of 35 cultivars have been described previ- ously. The exceptional subunit, found in cul- tivar Tammi (II), was assumed to be coded by genes on chromosome 1A at the Glu-Al locus because the cultivar contained its full alloca- tion of IB- and ID-encoded subunits, but none by chromosome IA. In addition, the subunit occurred as a thin band of slow mo- bility (Fig. 1, slot 4) typical of the commonly occurring 1A-encoded subunits 1 and 2* (Fig. 1, slots 3 and 5 respectively). It is proposed to number the subunit 25 and to call the allele Glu-Ald. This information will be included in the next update of the HMW glutenin sub- unit catalogue, with Tammi (II) as the stan- dard. The HMW glutenin subunit compositions of the 35 cultivars are listed in Table 2. On the basis of analysing six grains per cultivar only, four cultivars (Antti, Kiuru, Panu and Tammi (II) were shown to consist of at least two biotypes with different HMW glutenin subunits. Antti and Kiuru each contained two alleles at Glu-Al, the predominant one coding for subunit 1 and the other, the null allele, which does not produce a subunit. The sample of Panu grain analysed was highly mixed, for it contained two alleles at all three Glu-1 loci. Most of the cultivars analysed have also been given a HMW glutenin subunit quality (Glu-1 quality) score in Table 2. This was cal- culated by summing the scores assigned pre- viously to individual subunits as shown in Table 3. Unfortunately cultivars Panu, Sam- po and Tammi (II) could not be given a Glu-1 quality score because they each contained a HMW glutenin subunit which has not yet been associated with bread-making quality; subunit 20 for the first two cultivars and subunit 25 for Tammi (II). The Glu-1 quality score of a cultivar can range from a minimum of 3 to a maximum of 10. For wheat varieties bred Fig. I. SDS-PAGE of Finnish cultivars: slots 1, Veka; 2, Ruso; 3, Kimmo; 4, Tammi (II); 5, Hopea; 6, Ilves; 7, Aura; 8, Nisu; 9, Jyvä; 10, Linna. The region of the gel containing the HMW sub- units of glutenin is enclosed by brackets. The subunits have been numbered according to the nomenclature of Payne and Lawrence (1983). 153 Table 2. HMW glutenin subunit composition on Finn- ish varieties. Variety W/S HMW subunits 1A IB ID Score* + 1. Antti W 1 7+ 9 5+ 10 9 (N) - 2. Aura* W 2* 7+ 9 2+12 7 3. Elo W 1 7+ 9 2+12 7 4. lives* W 2* 7 s+lo 8 5. Jyvä W 2* 7+ 9 5+ 10 9 6. Linna* W 2* 7+ 9 2+12 7 7. Nisu* W 2* 7+ 9 5+ 10 9 8. Olympia W 1 7+ 9 2+12 7 9. Panu W 2* 20 2+12 (N) (7) (5 + 10) 10. Pitko* W 1 7 s+lo 8 11. Pohjola W 2* 7+ 9 2*12 7 12. Sampo W 1 20 2+12 13. Sukkula W 2* 7+ 9 2+12 7 14. Sukkula II W 2* 7+ 9 2+12 7 15. Vakka* W 2* 7 s+lo 8 16. Varma W 1 7+ 9 2+12 7 17. Villa W 2* 7+ 9 2+12 7 18. Apu S N 7+ 8 2+12 6 19. Hopea S 2* 7+ 8 5+ 10 10 20. Kimmo S 1 7+ 9 5+ 10 9 21. Kiuru S 1 7+ 8 5+ 10 10 (N) 22. Luja* S 2* 7+ 8 5+ 10 10 23. Pika S 2* 7+ 8 2+12 8 24. Pika II S N 7+ 9 2+12 5 25. Ruskea S 2* 7+ 8 2+12 8 26. Ruso* S 1 7+ 9 s+lo 9 27. Sopu S 2* 7+ 8 s+lo 10 28. Taava* S 1 7+ 9 5+ 10 9 29. Tähti* S 1 7+ 9 5+ 10 9 30. Tammi (II) S 25 7+ 9 s+lo (N) 31. Tapio S N 7+ 9 s+lo 7 32. Terä S 1 7+ 9 5+ 10 9 33. Touko S N 7+ 8 s+lo 8 34. Ulla S 2* 7+ 9 s+lo 9 35. Veka S 2* 6+ 8 5+ 10 8 * Currently grown commercially Glu-1 quality score, as discussed in the text Table 3. Bread-quality scores assigned to HMW sub- units of glutenin. Score Chromosome 1A IB ID 4 s+lo 3 1 7+B 2» 17+18 2 7 + 9 3+12 3 + 12 1 null 7 4+12 6+ 8 Further details on the assignments are described by Payne el al. (1987). Table 4. Frequencies of various HMW glutenin subunit compositions amongst varieties. Subunit composition No. % 1A IB ID 1. 1 7 s+lo 1 3 2. 1 7 + 8 s+lo 1 3 3. 1 7 + 9 2+ 12 3 8 4. 1 7 + 9 5 + 10 6 17 5. 1 20 2+12 1 3 6. 2* 6+ 8 s+lo 1 3 7. 2» 7 5+ 10 2 6 8. 2* 7 + 8 2+ 12 2 6 9. 2* 7 + 8 5 + 10 3 8 10. 2* 7 + 9 2+12 6 17 11. 2* 7 + 9 5+ 10 3 8 12. 2* 20 2+12 1 3 13. N 7 + 8 2+12 1 3 14. N 7 + 8 s+lo 1 3 15. N 7 + 9 2+12 1 3 16. N 7 + 9 5+ 10 2 6 17. 25 7 + 9 5+ 10 I 3 The above data includes the major biotypes only of Ant- ti, Kiuru and Panu. in Finland, the range is from 5 to 10 with an average of 8.0, which is very high. The 35 cultivars contain 17 different per- mutations of HMW glutenin subunits (Table 4). However, one third of the cultivars con- tain one of two HMW subunit compositions: 1,7 + 9 and 5 + 10, and 2*, 7 + 9 and 2 + 12. Only nine of the cultivars have com- positions that are unique in this collection. Discussion Previous studies have shown that there is a positive correlation between the Glu-1 qual- ity score of cultivars from several Western Eu- ropean countries and their bread-making qualities (Payne, 1986; Payne et al. 1987). By contrast there is a negative correlation between the score and the biscuit-making quality of 154 UK-grown wheats (Payne, et al. 1987). The Glu-1 quality score is probably therefore an indirect measure of dough strength. Finnish cultivars have the very high, average score value of 8.0. This is much higher than the mean scores of cultivars grown in the UK, West Germany(5.2 and 5.8 respectively; Pay- ne and Holt, unpublished data) and France (5.8; calculated from Branlard and Le Blanc, 1985), but the same as the average score of cultivars grown in Australia (8.0; cal- culated from Lawrence, 1986). The cause of the high mean score value fro Finnish cultivars is probably the long tradition in this country of breeding and growing wheat primarily for conversion into bread (Kivi, 1969), whereas in the UK for example, wheats are specifical- ly bred and grown for at least three different end uses: bread, biscuits and animal feed. The mean Glu-1 quality score of winter wheats currently grown in agriculture in Fin- land is 7.8, whereas for spring wheats the aver- age score is even higher, at 8.8. There is there- fore some prospect of improving the score of Finnish winter wheats in future varieties whereas one of the objectives for spring wheats should be to maintain the current, high score. The range and distributionof HMW glute- nin subunits found in Finnish-bred varieties is very limited compared to varieties grown elsewhere in Europe. Thus the chromosome 1A-encoded null allele is rare. Of the chromo- some 18-encoded subunits, subunit 7 is found only in Vakka, Ilves and Pitko and 6 + 8 only in Veka. Subunits 4+12 and 3 + 12, coded by genes on chromosome ID, are not found in any variety. The scarcity or absence of these subunits is advantageous because all of them have been associated with either mediocre or poor bread-making quality. However, if breeders in future use parental lines with greater genetic diversity than those currently used, these poor-quality subunits may be in- troduced into breeding programmes. SDS- PAGE of embryoless half-grains could then be used to advantage to screen against these subunits in subsequent generations. Subunits 17 + 18 are not present in any of the cultivars listed in Table 2. They are coded by genes on chromosome 1B and have been associated with good bread-making quality (Payne et al. 1984). The subunits are com- mon in cultivars ofAustralia and Central and Southern America (Lawrence, 1986; Payne, unpublished) and they have recently been in- troduced into the UK, France and Spain, in germplasm containing reduced-height (Rht) genes. It would be advantageous to transfer these storage-protein genes into Finnish wheats also. The limited number of combinations of HMW glutenin subunits amongst Finnish wheats causes SDS-PAGE to be of little value in varietal identification. By contrast, alumin- ium lactate-PAGE of the gliadin proteins has been successfully used to distinguish all the varieties that are currently grown in Finland (Sontag and Salovaara, 1985), except for Ruso and Taava. However, SDS-PAGE can easily detect the presence of protein biotypes in wheat cultivars. In the very preliminary study described here, based only on the analy- sis of six grains per cultivar, three varieties were shown to be genetically mixed (Table 2). Currently the presence of storage-protein bio- types in Finnish cultivars in agriculture is being examined in much more detail. Acknowledgements. We are grateful to chief inspec- tor Osmo Ulvinen in the Finnish Seed Testing Station for the wheat cultivar samples. References Branlard, G. & Le Blanc, A. 1985. Glutenins of bread and durum wheat cultivars in France. Agronomic 5: 467—477. Kivi, E.I. 1969. Sadonkäyttöarvo kevätvehnänjalostuk- sen tavoitteena. Ann. Agric. Fenn. 8: 193—204. Lawrence, G.J. & Shepherd, K.W. 1980. Variation in 155 glutenin protein subunits of wheat. Aust. J. Biol. Sci 33: 221—233. Lawrence, G.J. 1986. The high-molecular weight glute- nin subunit composition of Australian wheat cultivars. Aust. J. Agric. Res. 37: 125—133. Payne, P.L, Law, C.N. & Mudd, E.E. 1980. Control by homoeologous group 1 chromosomes of the high-mo- lecular-weight subunits of glutenin, a major protein of wheat endosperm. Theor. Appi. Genet. 58: 113—120. Payne, P. 1., Corfield, K.G., Holt, L.M. & Blackman, J.A. 1981 a. Correlations between the inheritance of certain high-molecular-weight subunits of glutenin and bread-making quality in progenies of six crosses of bread wheat. J. Sci. Fd. Agric. 32; 51—60. Payne, P. 1., Holt, L.M. & Law, C.N. 1981 b. Struc- tural and genetical studies on the high-molecular weight subunits of wheat glutenin. Part 1; Allelic variation in subunits amongst varieties of wheat (Triticum aesti- vum). Theor. Appi. Genet. 60: 229—236. Payne, P.1., Holt, L.M., Worland, A.J. & Law, C.N. 1982. Structural and genetic studies on the high-mo- lecular-weight subunits of wheat glutenin. Part 3. Telocentric mapping of the subunit genes on the long arms of the homoeologous group 1 chromosomes. Theor. Appi. Genet. 63: 129—138. Payne, P.I. & Lawrence, G.J. 1983. Catalogue of alleles for the complex gene loci, Glu-Al, Glu-81, Glu-DI which code for high-molecular weight subunits of glu- tenin in hexaploid wheat. Cer. Res. Commun. 11; 29—35. Payne, P.L, Holt, L.M., Jackson, E.A. & Law, C.N. 1984. Wheat storage proteins: their genetics and their potential for manipulation by plant breeding. Phil. Trans. R. Soc. Lond. B304: 359—371. Payne, P.I. 1986. Varietal improvement in the bread- making quality of wheat: contributions from biochemis- try and genetics, and future prospects from molecular biology. 1986BCPC Mono. No. 34. Biotechnology and crop improvement and crop protection, pp 69—81. Payne, P. 1., Nightingale, M.A., Krattioer, A.F.V. & Holt, L.M. 1987. The relationship between HMW glutenin subunit composition and the bread-making quality of British-grown wheat varieties. J. Sci. Fd. Agric. In the press. Sontag, T. & Salovaara, H. 1985. PAG electrophore- grams of wheat cultivars grown in Finland. J. Agric. Sci. Finl. 57: 271—277. Zillman, R.R. & Bushuk, W. 1979.Wheat cultivar iden- tification by gliadin electrophoregrams. 111. Catalogue of electrophoregram formulas of Canadian wheat cul- tivars. Can. J. PI. Sci. 59: 287—298. Ms received September 22, 1986 SELOSTUS Suomessa jalostettujen vehnälajikkeiden suurimolekyylisten gluteniinialayksiköiden koostumus Tuula Sontag, Hannu Salovaara ja Peter I Payne* Helsingin yliopiston elintarvikekemian ja -teknologian laitos. 00710 Helsinki ja � Plant Breeding Institute, Maris Lane, Cambridge CB2 2LQ, U.K. Suomessa jalostettujen vehnälajikkeiden(35) suurimo- lekyyliset gluteniinialayksiköt määritettiin SDS-polyak- ryyliamidigeelielektroforeesilla. Suomalaisista vehnälajik- keista löytyi vain 17 erilaista alayksiköiden yhdistelmää ja kolmasosa lajikkeista jakaantui kahden alayksikkö- yhdistelmän välille. Tutkituista lajikkeista neljä, Antti, Kiuru, Panu ja Tammi (11), olivat jonkin suurimolekyy- lisen gluteniinialayksikkönsäsuhteen geneettisesti sekoit- tuneita. Tammi (ll)-lajikkeesta löytyi uusi suurimolekyy- linen gluteniinialayksikkö (25), jota ei leipävehnillä ole aikaisemmissa tutkimuksissa löytynyt. Kromosomin IA lokuksessa Glu-Al olevien geenien oletetaan ohjaavan tä- män gluteniinialayksikön(25) tuotantoa. Tutkittujen la- jikkeiden suurimolekyylisten gluteniinialayksiköiden lei- vontalaatupisteet laskettiin aikaisemmissa tutkimuksissa osoitettujen gluteniinialayksiköiden ja leivontalaadun yh- teyksien perusteella. 156