«A. Kolodinska Brantestam Faculty of Landscape Planning, Hordiculture and Agricultural Science Department of Crop Science Alnarp Doctoral thesis ...»
Symbols for accessions are ● – two-rowed landraces and cultivars before 1930; ● – two-rowed cultivars 1931-1970; ○ – two-rowed cultivars after 1971 and breeding lines; ▲ – six-rowed landraces and cultivars before 1930; ▲ – six-rowed cultivars 1931-1970; ∆ – six-rowed cultivars after 1971 and breeding lines.
In the Nordic and Baltic material, the diversity changes were detected by the analysis of agronomic traits. As expected, the highest diversity was detected in landraces and old cultivars (based on Euclidean distances and coefficient of variation). This was also observed when molecular markers were analyzed (based on Nei and Shnannon-Weaver diversity indexes). However, the overall significance of this decrease could not be proven. In the marker studies (isozymes, ISSRs and SSRs), unique alleles were found in landraces and cultivars from before 1930 that could not be found in material from later periods. In modern material, however, other unique alleles not found in earlier cultivars were detected. This result is similar to that found by Donini et al. (2001) in UK barley and Cristiansen et al. (2002) in Nordic wheat.
20 Significant changes in genetic diversity were detected in material from the southern part of the region, but not in that from the north. ISSR and SSR markers both demonstrated a decrease in diversity in the south (Fig. 12).
Fig. 12. Comparison of diversity values in cultivars from different breeding periods in the northern and southern parts of the region (ISSR and SSR data) HTN Nei 1987 diversity index, HTSW- Shannon-Weaver diversity index, ■ – landraces and cultivars befor 1930; ■ – cultivars 1931-1970; □ – cultivars after 1971 and breeding lines * north of 58ºN (Estonia, Finland, Norway and northern Sweden), ** south of 58ºN (Denmark, Latvia, Lithuania and southern Sweden).
These differences in diversity changes could be explained by the fact that cultivars from the north have a broader genetic base, due to adaptation breeding.
SSR markers demonstrated an increase in diversity in the south after 1970, whereas other markers did not. Since at least half the SSR markers showing significant changes in the south of the region are associated with agronomic traits and probably located near gene-rich regions, the increase in diversity in modern material could visualize the accumulation of different genes. This may be based on introductions of non-Nordic material and use of exotic gene sources in later breeding periods.
The diversity changes over time were also dependent on the country of origin.
For example, a significant decrease in diversity was found in the middle of the 20th century in Danish material both by ISSR and SSR markers, whereas in Norwegian material no significant changes were observed, although there was a tendency for 21 a slight increase. In two-rowed and six-rowed cultivars, there was an indication of a decrease in diversity in several agronomic traits. Molecular markers showed the same tendency, although the decrease was not significant. The only exception was in six-rowed cultivars, where ISSR data showed a significant decrease in the middle of the century, but modern cultivars appeared to be as variable as the old ones. The drop in diversity detected by ISSR might be explained by the fact that after 1930 the use of six-rowed barley decreased dramatically in the south and only two cultivars from this part were included in the study (‘Priekuļu 1’ and ‘Agra’ from Latvia). However, both these cultivars are derived from Norwegian and Finnish material. The increase in diversity after 1970 in six-rowed material, as shown by ISSR, could be explained by the fact that two-rowed cultivars from the south part and non-Nordic introductions were used in the breeding of Norwegian and Finnish six-rowed cultivars.
Conclusions Based on the molecular and agronomic studies of Nordic and Baltic barley material from the 20th century described in this thesis, the following conclusions
can be drawn:
There has been a distinct decrease in genetic variability of agronomic traits The decrease in variation shown by molecular markers was not significant throughout the whole data set In the southern parts of the region, it was possible to detect a significant decrease in diversity using ISSR markers The SSR data showed a decrease in diversity in material from southern parts in the middle of the last century, but in modern cultivars it appeared to increase again Diversity changes were different between the investigated countries Two-rowed and six-rowed barley cultivars were clearly differentiated by agronomic and DNA data, but not by isozymes The differentiation between two-rowed and six-rowed cultivars were also determined by loci different from the inflorescence-determining genes In general, modern and old material were separated by agronomic data and not by marker data The differentiation between old versus modern material could be detected by ISSR markers when material was analysed separately by country The differentiation between old versus modern material by SSR markers was more pronounced in the material from the southern parts of region than in that from northern parts 22 This study in general indicated a decrease in genetic diversity during breeding.
The significance of this overall decrease could not be proven, although it was significant for some geographical regions and traits. Some losses of alleles were also detected. This shows that conservation of Nordic and Baltic landraces and old cultivars is important, because they are sources of genetic diversity that might become import for future breeding. The significant decrease in genetic diversity in some of the barley groups and traits also reveals the importance of monitoring diversity changes in the regions in order to improve breeding strategies and to maintain prosperous barley cultivation in the future.
References Aikasalo, R. 1988. The results of six-row barley breeding and the genetic origin of varieties released. Journal of Agricultural Science in Finland 60, 293-305.
Arnell, N.W. 1999. The effect of climate change on hydrological regimes in Europe a continental perspective. Global Environmental Change 9, 5-23.
Asfaw, Z. & von Bothmer, R. 1990. Hybridization between landrace varieties of Ethiopian barley (Hordeum vulgare ssp. vulgare) and the progenitor of barley (H. vulgare ssp.
spontaneum). Hereditas 112, 57-64.
Ayoub, M., Symons, S.J., Edney, M.J. & Mather, D.E. 2002. QTLs affecting kernel size and shape in two-rowed by six-rowed barley cross. Theoretical and Applied Genetics 105: 237-247.
Äyräväinen, K. 1976. Yield composition of two-rowed and multi-rowed barleys in drilled and single-plant populations in southern and northern Finnish experiments. Journal of Agricultural Sciences Finland 48, 13-31.
Baek, H.J., Beharav, A. & Nevo, E. 2003. ecological-genomic diversity of microsatellitesin wild barley, Hordeum spontaneum, populations in Jordan. Theoretical and Applied Genetics 106, 397-410.
Baker, B., Zambryski, P., Staskawicz, B. & Dinesh-Kumar, S.P. 1997. Signaling in plantmicrobe interactions. Science 276, 726-733.
Barakat, A., Carels, N. & Bernardi, G. 1997. The distribution of genes in the genomes of Gramineae. Proceedings of the National academy of Sceinces of the United Sates of America 94, 6857-6618.
Becker J., Vos, P., Kuiper, M., Salamini, F. & Heun, M. 1995. Combined mapping of AFLP and RFLP markers in barley. Molecular and General Genetics 249, 65-73.
Bothmer, R. von, Jacobsen, N., Baden, C., Jørgensen R.B. & Linde-Laursen, I. 1995. An ecogeographical study of the genus Hordeum. Systematic and Ecogeographic Studies of Crop Genepools, 7. IPGRI, Rome, 2nd ed., pp.129.
Bothmer, R. von, Sato, K., Komatsuda, T., Yasuda, S. & Fishbeck, G. 2003. The domestication of cultivated barley. In R. von Bothmer, T van Hintum, H. Knüpffer and K. Sato (ed.) Divarsity in barly, The Netherlands, ELSEVIER, pp. 3-27.
Bowman, J.G.P., Blake, T.K., Surber, L.M.M., Habernicht, D.K. & Bockelman, H. 2001.
Feed-quality variation in the barley core collection of the USDA national small grains collection. Crop Sciences 41, 863-870.
Browing, J.A. 1988. Current thinking on the use of diversity to buffer small grains against highly epidemic and variable foliar pathogems: Problems and future prospectives, In SIMMYT Breeding strategies for resistance to the rusts of wheat. D.F. CIMMYT, Mexico pp. 76-90.
Clancy, J.A., Han, F., Ullrich, S.E. & the North American Barley Genome Project 2003.
Comparative mapping of β-amylase activity QTLs among three barley crosses. Crop Sciences 43, 1043-1052.
23 Clegg, M.T., Brown, A.H.D. & Whitfeld, P.R. 1884. Chloroplast DNA diversity in wild and cultivated barley: implication for genetic conservation. Genetic Resources 43, 339Christiansen, M.J., Andersen, S.B. & Ortiz, R. 2002. Diversity changes in an intensively bred wheat germplasm during the 20th century. Molecular Breeding 9, 1-11.
Czembor, H.J. & Czembor, J.H. 2000. Sources of powdery mildew resistance in barley landraces from Marocco. Proceedings of the 8th International Garley Genetics Symposium Vol III, Adelaide, Australia, 92-94.
Danmarks statistik 1968. Landbrugsstatistik 1900-1965, I, København DeScenzo, R.A. Wise, R.P. & Mahadevappa, M. 1994. High-resolution mapping of the Hor1/Mla/Hor2 region on chromosome 5S in barley. Molecular Plant-Microbe Interactions 7, 657-666.
Donini, P., Law, J.R., Koebner, R.M.D., Reeves, J.C. & Cooke, R.J. 2001. The fate of microsatellite alleles in winter and spring barley varieties grown in the UK over the past 70 years. (P261) Plant & animal Genome IX Conference, San Diego, pp 126.
Druka, A., Kudrna, D., Kannangara, C.G., von Wettstein, D. & Kleinhofs, A. 2002.
Physical and genetic mapping of barley (Hordeum vulgare) germin-like cDNAs.
Proceedings of the National academy of Sceinces of the United Sates of America 99: 850Dubcovsky, J., Ramakrishna, W., SanMiguel, P.J., Busso, C.S., Yan, L., Shiloff, B.A. & Bennetzen, J.L. 2001. Comparative Sequence Analysis of Colinear Barley and Rice Bacterial Artificial Chromosomes. Plant Physiology 125, 1342-1353.
Ellis, R.P., McNicol, W., Baird, E., Booth, A. & Lawrence, P. 1997. The use of AFLPs to examine genetic relatedness in barley. Molecular Breeding 3, 356-369.
Fageria, N.K., Balligar, V.C. & Jones, C.A. 1997. Growth and Mineral Nutrition of Field Crops. Marcel Dekker, New York.
FAO 2004. http://apps.fao.org Fetch, T.G.J., Steffenson, B.J. & Nevo, E. 2003. Diversity and sources of multiple disease resistance in Hordeum spontaneum. Plant Disease 12, 1439-1448.
Fischbeck, G. 1992. Barley cultivar development in Europe – success in past and possible changes in the future. Barley Genetics 4: 885-901.
Fischbeck, G. 2002. Contribution of barley to agriculture: a brief overview. In G. Slafer, J.S. Molina-Cano, R. Savin, J.L. Araus and I. Romagosa (ed.) Barley Science Recent Advances from Molecular Biology to Agronomy of Yield and Quality, New York, Food Progucts Press, pp. 1-29.
Fischbeck, G. 2003. Diversification through breeding. In R. von Bothmer, T van Hintum, H. Knüpffer and K. Sato (ed.) Diversity in barly, The Netherlands, ELSEVIER, pp. 3-27 Forester, B.P., Russel, J.R., Ellis, R.P., Handley, L.L., Robinson, D., Hackett, C.a., Nevo, E., Waugh, R., Gordon, D.C., Keith, R. & Powell, W. 1997. Locating genotypes and genes for abiotic stress tolerance in barley, a strategy using maps, markers and species.
New Phytologist 137, 141-147.
Franckowiak, J. 1997. Revised linkage maps for morphological markers in barley, Hordeum vulgare. Barley Genetics Newsletter 26, 9-21.
Gaike, M. 1992 Vasaras mieži. In I. Holms (ed.) Laukaugu selekcija Latvijā. Rīga: Avots, pp. 53-63.
Garvin, D.F, Brown, A.H.D. & Burdon, J.J. 1997. Inheritance and chromosome locations of scald-resistance genes derived from Iranian and Turkish wild barleys. Theoretical and Applied Genetics 94, 1086-1091.
Graner, A., Bjørnstad, Å., Konishi, T. & Ordon, F. 2003. Molecular diversity of the barley genome. In R. von Bothmer, T. van Hintum, H. Knüpffer and K. Sato (ed.) Divarsity in barly, The Netherlands, ELSEVIER, pp. 121-141.
Grausgruber, H., Bointer, H., Tumpold, R. & Ruckenbauer, P. 2002. Genetic improvement of agronomic traits of spring barley. Plant Breeding 121, 411-416.
Jana, S. & Bailey, K.L. 1995. Responses of wild and cultivated barley from west Asia to the net blotch and spot blotch. Crop sciences 35, 242-246.
24 Hammer, K., Knüpffer, H., Xhuveli, L. & Perrino, P. 1996. Estimating genetic erosion in landraces-two case studies. Genetic Resources and Crop Evolution 43, 329-336.
Harlan, J.R. 1970. On the origin of barley: a second look. Barley Genetics II, 45-50.
Harlan, J. R. 1975. Our vanishing genetic resources. Science 188, 618-621 Harlan, J.R. 1995. Barley. In J. Smartt and N.W. Simmonds (ed), Evolution of Crop Plants, 2nd ed., Longman Scientific and Technical, pp. 140-147.
Harlan, J.R., & Wet, J.M.J. de 1971. Toward a rational classificarion of cultivated plants.
Taxon 20, 509-517.
Hayes, P.M., Castro, A., Marquez-Cedillo, L., Corey, A., Henson, C., Jones, B.L., Kling, J., Mather, D., Matus, I., Rossi, C. & Sato, K. (2003) Genetic diversity for quantitatively inherited agronomic and malting quality traits. In R. von Bothmer, T van Hintum, H.
Knüpffer and K. Sato (ed.) Divarsity in barly, The Netherlands, ELSEVIER, pp. 201Helms Jørgensen, J. 1992. Discovery, characterisation and exploitation of Mlo powdery mildew resistance in barley. Euphytica 63, 141-152.
Hjelmqvist, H. 1955. Die älteste Gescichte der Kulturpflanzen in Schweden. Opera Botanica 1, 3.
Hoffman, D. & Dahleen, L. 2002. Markers polymorphic among malting barley (Hordeum vulgare L.) cultivars of a narrow gene pool associated key QTLs. Theoretical and Applied Genetics 105, 544-554.
Hori, K., Kobayashi, T., Shimizu, A., Sato, K., Takeda, K. & Kawasaki, S. 2003. Efficient construction of high-density linkage map and its application to QTL analysis in barley.
Theoretical and Applied Getetics 107, 806-813.
Hunt, C.W. 1996. Factors affecting the feeding quality of barley for ruminants. Animal Feed Science Technology 62, 37-48.
Jahoor, A. & Fishchbeck, G. 1993. Identification of New genes for mildew resistance of barley at the mla locus in lines derived from Hordeum spontaneum. Plant breeding 110, 116-122.