Summary
Results from a cooperative breeding programme with timothy for the northern areas of Scandinavia are presented. The main aim of the programme was to identify genotypes for synthetic populations that are high yielding, adapted over the whole area and stable over years. A polycross comprising 12 genotypes from each of five sites within the region was formed. The subsequent 60 half-sib families and four reference varieties were then compared under sward conditions at the same sites. The trials lasted for three years and results for total dry matter yields are presented.
Significant differences in yield between lines were found. There were also significant two and three factor interactions between lines, sites and years. A new two-step procedure is presented to select the genotypes to make up a synthetic variety. Firstly, a superiority measure (Q-value) is used to select a group of genotypes that are high yielding and stable over sites and years. Secondly, the GxE part of the Q-value is split into two terms. One measures adaptation to predictable environmental conditions. The other one measures stability to unpredictable changes in the environment. A plot of these two measures provides a tool for discarding unstable or poorly adapted genotypes. The statistical properties of the selection parameters are discussed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Allard, R.W. & A.D., Bradshaw, 1964. Implications of genotype-environment interactions in applied plant breeding. Crop Sci. 4: 503–507.
Becker, C. & J., Léon, 1988. Stability analysis in plant breeding. Plant Breeding 101: 1–23.
Björnsson, H., 1978. Analysis of series of long-term grassland experiments with autocorrelated errors. Biometrics 34: 645–651.
Björnsson, H., 1993. Zones for testing timothy (Phleum pratense L.) in the Nordic countries. Acta Agriculturae Scandinavica, Section B. Soil and Plant Science 43: 97–113.
Björnsson, H., 1995. On the contribution of year effects to the GxE interaction in timothy, results from Nordic variety trials. Submitted to Acta Agric Scand, Sect B. Soil and Plant Sci.
Cochran, W.C. & G.M., Cox, 1957. Experimental Designs, 2nded., John Wiley & Sons, Inc., New York.
Dennis, B. & A[']. Helgadóttir, 1988. Breeding herbage species for northern Scandinavia. In: Natural Variation and Breeding for Adaptation, pp. 169–177. Proceedings of the Eucarpia Fodder Crops Section Meeting, Lusignan, France.
Eberhart, S.A. & W.A., Russell, 1966. Stability parameters for comparing varieties. Crop Sci. 6: 36–40.
Finlay, K.W. & G.N., Wilkinson, 1963. The analysis of adaptation in a plant-breeding programme. Aust. J. Agric. Res. 14: 742–754.
Helgadóttir, A[']., 1989. Breeding herbage species for northern areas. 1. Variety trials with timothy (Phleum pratense L.). Acta Agric. Scand. 39: 243–254.
Helgadóttir, A[']. & T.A., Kristjánsdóttir, 1991. Simple approach to the analysis of GxE interactions in a multilocational spaced plant trial with timothy. Euphytica 54: 65–73.
Helgadóttir, A[']. & H., Bjömsson, 1994. Cooperative breeding for the northern marginal areas. Euphytica 77: 221–230.
Lin, C.S. & M.R., Binns, 1988a. A superiority measure of cultivar performance for cultivar x location data. Can. J. Plant. Sci. 68: 193–198.
Lin, C.S. & M.R., Binns, 1988b. A method of analyzing cultivar x location x year experiments: a new stability parameter. Theor. Appl. Genet. 76: 426–430.
Lin, C.S. & M.R., Binns, 1991. Assessment of a method for cultivar selection based on regional trial data. Theor. Appl. Genet. 82: 379–388.
Lin, C.S. & M.R., Binns, 1991. Assessment of a method for cultivar selection based on regional trial data. Theor. Appl. Genet. 82: 379–388.
Lin, C.S., M.R., Binns & L.P., Lefkovitch, 1986. Stability analysis: Where do we stand? Crop Sci. 26: 894–900.
Olesen, K. & O.J., Olesen, 1973. A polycross pattern formula. Euphytica 22: 500–502.
Patterson, H.D. & R., Thompson, 1971. Recovery of inter-block information when block sizes are unequal. Biometrika 58: 545–554.
Payne, R.W. et al., 1990. Genstat 5, Release 2 Reference Manual Supplement. NAG Ltd. Oxford, 131 pp.
Rognli, O.A., 1988. Species aspects of breeding herbage varieties for northern marginal regions. J. Agric. Sci. Finl. 60: 181–189.
Schjelderup, I., K., Aastveit, P., Marum & A.H., Aastveit, 1992. Results of progeny testing and selection in timothy (Pheleum pratense L.). Norw. J. Agric. Sci. 6: 349–373.
Schjelderup, I., A.H. Aastveit & K. Aastveit, 1994. Winter hardiness in marginal populations of timothy. In: Breeding for Marginal Conditions. Proceedings of the Eucarpia Fodder Crops Section Meeting, Loen, Norway. Supplement to Euphytica, in press.
Simonsen, Ö, 1985. Herbage breeding in northern areas. In: A., Kaurin, O., Junttila & J., Nilsen (Eds.). Plant Production in the North, pp. 277–295. Norwegian University Press, Oslo.
Westcott, B., 1986. Some methods of analysing genotype-environment interaction. Heredity 56: 243–253.
Yates, F. & W.G., Cochran, 1938. The analysis of groups of experiments. J. Agric. Sci. 28: 556–580.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Helgadóttir, A., Björnsson, H. & Kristjánsdóttir, T.A. Analysis of a site x year experiment with timothy polycross progeny. Euphytica 82, 241–251 (1995). https://doi.org/10.1007/BF00029567
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00029567