Epistasis in Maize (Zea mays L.) III. Comparison of Single and Three-Way Crosses for Forage Traits |
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| Authors: | A E Melchinger H H Geiger G Seitz G A Schmidt |
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| Institution: | Dr. A. E. Melchinger;, Prof, Dr. H. H. Geiger, Dipl.-Agr. biol. G. Seitz, Institut für Pflanzenzüchtung, Saatgutforschung und Populationsgenetik, Universität Hohenheim, D-7000 Stuttgart 70 (Germany. F. R.) Dr. G. A. SCHMIDT, KWS-France, Le Fayel, F-60680 Grand-fresnoy (France). |
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| Abstract: | The importance of epistasis for forage performance and quality traits was studied in early maturing European maize (Zea mays L.) breeding materials. Sixty-six three-way crosses (3W), 33 of the flint x (dent · dent) and 33 of the dem × (flint · flint) type, were compared with the mean of their respective non-parental single crosses () using data obtained in six environments. For each of the 11 traits examined, at least 6 out of the 66 three-way crosses displayed significant (P < 0.05) epistatic deviations, calculated as – 3W. Averaged over crosses and environments, epistatic deviations were highly significant (P < 0,31] for 8 trails, but of minor importance except for grain yield. In general, the variance of epistatie deviations was appreciably smaller than the variance of genotype × environment interactions. Highly significant correlations occurred among epistatie deviations for silking date, dry matter content of ear, and dry matter yield of grain and stover. The reliability of predicting the performance of three-way crosses from 2W as opposed to assessing them directly was investigated as a function of the number of test environments. Disturbing e fleets of epistasis on prediction only became important under intense testing (> 3 or 4 environments), With fewer test environments, both procedures were almost equivalent, due to a smaller influence of genotype × environment interaction on the values, Epistasis is concluded to be of minor importance with regard to the optimum type of hybrid for forage use. |
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| Keywords: | Key words Zea mays forage maize epistasis genotype × environment interaction hybrid prediction type of hybrid |
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