Rice is the most important food crop both in value and
volume for the Asian population. Frequent drought, flood
and salinity stresses exacerbated by global climate change
adversely affect rice ...production in more than fifty percent
of the rice growing areas. Green revolution high yielding
varieties carrying sd1 dwarfing gene have almost fully
replaced the traditional climate resilient landraces and
varieties of rice. However, these were bred primarily for
yield under high input conditions and therefore are sensitive
to adverse climatic conditions. Hence, there is urgent need
to combine the high productivity with climate resilience.
Knowledge of rice genome and genes for tolerance to
different abiotic stresses provided us an opportunity to
transfer favorable alleles of these genes into high yielding
varieties through genomics-assisted backcross breeding
through multi-institutional networks. Six consistent
genomic regions (QTLs) for grain yield under drought;
namely qDTY1.1, qDTY2.1, qDTY2.2, qDTY3.1, qDTY3.2 and
qDTY12.1 have been transferred to flood tolerant versions
of mega varieties of rice, Swarna, Samba Mahsuri and IR 64.
To address the problem of flash flooding qSUB1 QTL has
been transferred to nine popular rice varieties, namely ADT
46, Bahadur, Ranjit, HUR 105, Sarjoo 52, Pooja, Pratikshya
MTU 1075 and Rajendra Mahsuri. Further, qSALTOL1 QTL
for seedling stage salt tolerance and qSSISFH8.1 for
reproductive stage salt tolerance have been transferred to
six popular rice varieties, ADT 45, Gayatri, MTU 1010, PR
114, Pusa 44 and Sarjoo 52. We used foreground selection
markers for the presence of desired gene/QTL and
recombinant selection markers for reduction of linkage drag
around these genes. Genotypic background selection was
done after BC3F3 stage using a 50K SNP chip on a set of 20
advance lines obtained by phenotypic selection for
closeness to the recipient parents. Near-isogenic lines
(NILs) with more than 95% similarity to the recipient parent
genome have been released and notified for commercial
cultivation and are gaining fast popularity. These climate
smart rice varieties will provide production stability in the
adverse ecologies and support farmer’s income and
livelihood.
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