|
|
||||||||
a State Plant Breeding Institute, University of Hohenheim, 70593 Stuttgart, Germany
b Institute of Plant Breeding, Seed Science, and Population Genetics, University of Hohenheim, 70593 Stuttgart, Germany
* Corresponding author (melchinger{at}uni-hohenheim.de)
Triticale (xTriticosecale Wittmack) (genomes AABBRR, 2n = 6x = 42) hybrid breeding and heterosis have received increased attention in recent years, but a comprehensive study is lacking. We investigated (i) the level of heterosis, (ii) the relative importance of general combining ability (GCA) vs. specific combining ability (SCA), (iii) correlations between GCA and line per se performance, (iv) trait correlations in parents and hybrids, and (v) prospects for hybrid breeding. Two hundred nine F1 hybrids of winter triticale, produced by a chemical hybridizing agent, together with their 57 female parents and five tester (male) lines were evaluated in six environments in Germany during the season 20012002. Midparent heterosis for grain yield averaged 10.3% and varied from 11.4 to 22.4%, whereas better-parent heterosis averaged 5.0% and varied from 16.8 to 17.4%. Midparent heterosis was also positive for 1000-kernel weight, number of kernels per spike, test weight, and plant height but negative for number of spikes per square meter, falling number, and protein concentration. GCA variance
was more important than SCA variance
for all traits except grain yield and protein concentration. For most traits, GCA x location and SCA x location interaction variances were small relative to
2GCA and
2SCA, respectively. Genetic correlations between midparent and hybrid performance and between GCA effects and line per se performance showed similar trends, being moderate for grain yield and protein concentration and higher for the other traits. We concluded that grain yield heterosis in winter triticale crosses from parents in the current European germplasm pool is adequate to justify continuing research on hybrid breeding. By selecting parents for combining ability and establishing genetically diverse heterotic groups, a midparent grain yield heterosis of 20% could presumably be surpassed. Further information is needed on F1 seed production and the cytoplasmic male sterility system.
Abbreviations: BPH%, relative better-parent heterosis CHA, chemical hybridizing agent GCA, general combining ability HYB, hybrid performance LP, line per se performance MP, midparent value MPH, absolute midparent heterosis MPH%, relative midparent heterosis SCA, specific combining ability
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Vadose Zone Journal | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||