Detection of stay-green QTL in a sorghum recombinant inbred population based on cross (N13 × E36-1)P SGaikwadauthorS PMehtreauthorVVadezauthorC THashauthorS PDeshpandeauthorThe progress in genetic improvement of post-rainy sorghum
for drought tolerance using traditional plant breeding practices
has been slow, and selection has not been much effective due
to complex interaction between genotype and environment.
Identification of genetic factors involved in stay-green through
molecular breeding approaches would provide the basis for
genetic improvement for drought tolerance. In this experiment
stay-green QTLs were mapped and the effect of environment
on stay-green expression was observed. For this a sorghum Recombinant
Inbred Line (RIL) population was field evaluated for
2 years during the post-rainy season of 2011 and 2012, under
two water regimes, (stress and control). A set of 200 entries,
including 180 RILs, parents and checks were sown in a plot
of 2 rows of 2m in RCBD design with 3 and 2 replications for
stress and control treatments, respectively. Data was recorded
for percent green leaf area (%GLA) with a weekly interval
basis (7 counts) with starting from 50% flowering till physiological
maturity. This reveals significant genotypic variances
along with high heritability. A genetic linkage map based on
176 RILs with 271 markers consisting of SSRs, DArT and two
qualitative traits was developed. In total 45 QTLs were identified
for seven %GLA scores in two seasons and two treatments.
The phenotypic variation explained by each QTL ranged
from 6.00 to 14.00%. In further across environment analysis,
some QTLs may be environment specific and some may consistent
across environment, such stable QTLs could be utilized
through genomics approaches to improve drought tolerance of
post rainy sorghum varieties.Plant BreedingSorghumGenetics and Genomics2017-02Conference or Workshop Item