| Autor: |
Cowling WA; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia.; UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA 6009, Australia., Castro-Urrea FA; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia.; UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA 6009, Australia., Stefanova KT; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia., Li L; Animal Genetics and Breeding Unit, University of New England, Armidale, NSW 2351, Australia., Banks RG; Animal Genetics and Breeding Unit, University of New England, Armidale, NSW 2351, Australia., Saradadevi R; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia.; UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA 6009, Australia., Sass O; Norddeutsche Pflanzenzucht Hans-Georg Lembke KG, Hohenlieth, 24363 Holtsee, Germany., Kinghorn BP; School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia., Siddique KHM; The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia.; UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA 6009, Australia. |
| Abstrakt: |
Crop breeding must achieve higher rates of genetic gain in grain yield (GY) and yield stability to meet future food demands in a changing climate. Optimal contributions selection (OCS) based on an index of key economic traits should increase the rate of genetic gain while minimising population inbreeding. Here we apply OCS in a global spring oilseed rape (canola) breeding program during three cycles of S 0,1 family selection in 2016, 2018, and 2020, with several field trials per cycle in Australia and Canada. Economic weights in the index promoted high GY, seed oil, protein in meal, and Phoma stem canker (blackleg) disease resistance while maintaining plant height, flowering time, oleic acid, and seed size and decreasing glucosinolate content. After factor analytic modelling of the genotype-by-environment interaction for the additive effects, the linear rate of genetic gain in GY across cycles was 0.059 or 0.087 t ha -1 y -1 (2.9% or 4.3% y -1 ) based on genotype scores for the first factor (f 1 ) expressed in trait units or average predicted breeding values across environments, respectively. Both GY and yield stability, defined as the root-mean-square deviation from the regression line associated with f 1 , were predicted to improve in the next cycle with a low achieved mean parental coancestry (0.087). These methods achieved rapid genetic gain in GY and other traits and are predicted to improve yield stability across global spring canola environments. |
