Genetic and molecular studies on morpho-physiological traits for thermo tolerance in indian mustard [Brassica juncea (L.) Czern & Coss.]
Loading...
Date
2016
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
Analysis of variance for morphological as well as physiological characters showed that
the mean sum of squares were significant for almost all the traits in both the environments.Mean
squares due to parent v/s crosses were also significant for all the traits, except for days to
maturity, plant height, siliquae on main shoot, siliqua length, oil content, canopy temperature at
50 DAS, chlorophyll fluorescence(Fv/Fm)at 40 DAS, chlorophyll fluorescence(Fv/Fm) at 50
DAS and chlorophyll fluorescence (Fv/Fm)at 60 DAS in timely sown condition and plant height,
number of primary branches per plant, siliquae on main shoot,1000 seed weight, canopy
temperature at 50 DAS and canopy temperature at 70 DAS in late sown condition. The estimates
of D were significant for siliquae on main shoot, number of seeds per siliqua, siliqua length,
canopy temperature (0C) at 40, 60 and 70 DAS in both the environments whereas 1000 seed
weight, chlorophyll fluorescence (Fv/Fm) at 40, 50, 60, 70 DAS and seedling mortality in timely
sown condition and oil content in late sown condition were significant. The heritability (ns)
showed the prevalence of additive variance for siliqua length, canopy temperature (0C) at 40 and
60 DAS in both environments, while for other traits an appreciable proportion of total variance
was non-additive in both the environments. In the present study, an overall appraisal of gca effects
revealed that parent RH0735 and BPR349-9 in timely sown condition and RH0116 and RH0555A
late sown condition were good general combiners for majority of the characters. The crosses
RH8814 x RH0555A, RH0644 x BPR543-3 and BPR349-9 x RH0644 in timely sown condition
and crosses RH0555A x RH0644, RH0735 x RH0116 and BPR349-9 x RH0644 in late sown
condition were identified as promising on the basis of their high per se performance, average
heterosis, heterobeltiosis and significant sca effects for seed yield. These crosses could be
extensively used in breeding programme to develop superior segregants in further breeding
programmes. A total of 50 SSR primers were used, in which 42 markers were monomorphic
among eight genotypes, 5 markers were polymorphic and remaining markers did not show
amplification. Based on similarity index data, the eight genotypes grouped into two clusters.
RH8814, RH0735, RH0116 and BPR349-9 fall into group first and RH0952, RH0555A, RH0644
and BPR543-3 fall into group second.