Indian Society of Genetics & Plant Breeding
Identification of environments favouring selection of
superior genotypes should help plant breeders reduce the
costs of multi-environment evaluations. The objectives of
this study were to develop indices which measure
suitability of environments for conducting selection and
to apply the indices to a multi-location experiment in
maize (Zea mays L.). The indices were derived using the
rationale that selection in a suitable environment should
lead to a high response in the target environments. The
value of a selection environment was found to be a
product of linear regression coefficient of the observed
performance of genotypes in the target environment on
the performance in the selection environment and standard
deviation of the performance in the selection environment.
It was termed as an index of general response to selection
(GR index) when based on the performance averaged over
a number of target environments. The correlation ((15)
between the average performance across target
environments and that in a selection environment was
shown to quantify the GR index and the ratio of response
to indirect vs. direct selection. The 18 locations evaluated
differed for GR index, (15 and discriminability (DA; linear
regression of the performance of genotypes in a selection
environment on the average performance across all target
environments); (15 was closely correlated with GR index;
and some locations possessed high GR index as well as
DA with respect to maize grain yield. The study gave the
indices that are useful in characterizing the suitability of
environments for conducting selection and in choosing
environments better than others for conducting selection
for grain yield in maize
Keywords: Selection environment, response to selection, discriminability, maize, grain yield
Year: 2001
Volume: 61
Issue: 1
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
B. S. Dhillon info_circle
Download PDF