Geneticanalysis of drought stress response in rapeseed (Brassica campestris and B. Napus). II. Yield improvement and the application of selection indices |
| |
Authors: | R A Richards N Thurling |
| |
Institution: | (1) Department of Agronomy, University of Western Australia, 6009 Nedlands, Western Australia;(2) Present address: Division of Plant Industry, CSIRO, P.O.Box 1600, A.C.T. 2601 Canberra City, Australia |
| |
Abstract: | Summary The expected improvement in grain yield if selection was made for plant characters measured between flowering and maturity was evaluated in populations of rapeseed (Brassica campestris and B. napus) grown in a droughted environment. Drought was commenced at flowering in each species and measurements were made on plants at the commencement of the drought stress, during the stress treatment and at crop maturity.Substantial genetic and phenotypic variation was observed in yield as well as the different morphophysiological determinants of yield. In B. campestris no single parameter was found to be a suitable alternative selection criterion to yield since the correlated responses in yield if selection was for another character was lower than if selection was for yield alone. By the use of a selection index however, joint selection for yield, as well as harvest index, 1000 seed weight and seeds per pod, was expected to be 20% more effective than direct selection for yield under drought. In the B. napus population direct selection for flowering time or for harvest index was predicted to result in a genetic advance in yield equal to or greater than that obtained by direct selection for yield, whereas joint selection for flowering time and yield should result in a 16% greater yield increase. Selection for increased yield in these populations grown in droughted conditions is discussed. |
| |
Keywords: | Brassica campestris B napus rapeseed drought stress genetic analysis selection index grain yield |
本文献已被 SpringerLink 等数据库收录! |
|