Stability analysis of backcross population for salinity tolerance at reproductive stage in rice

Abstract

Significant yield reduction was recorded at flowering stage
in rice varieties under salinity stress. But due to high
genotype x environment interaction (GEI) the adaptability
of the salt tolerant elite lines is generally poor. The identified
source of tolerance, AC41585, was used in developing a
backcross population. One hundred eighty BC3F4 lines were
evaluated under stress (EC 8dSm–1) and non-stress
conditions in net-house during the years 2012 and 2013.
Under salinity stress plant yield was observed to be
associated positively with the number of panicles/plant,
panicle length, harvest index and negatively with the
percentage of spikelet sterility and degeneration. Genotypes
such as, L-41, L-45, L-112, L-171, L-192 with low IPCA and
higher mean were identified with general adaptability
through AMMI analysis. In addition, ‘which-won-where’
pattern of GGE Biplot detected L-192 and L-41 as highest
performing genotypes in saline and non-saline
environments, respectively. Both the analyses identified
stable introgression line L-171 with high yield stability index
having phenotypic similarity with recurrent parent, IR 64.
The elite lines selected through the present study could be
used in rice breeding and also to investigate the molecular
basis of salt tolerance at reproductive stage.