Rice, the most important staple food crop in Asia is commonly grown by
transplanting seedlings into puddled soil and standing water. Despite the
multiple benefits of manual puddled transplanted rice (PTR), it is a highly
labor-, water-, and energy-intensive system, making it less sustainable,
less profitable, and less attractive to farmers. In the face of changing
Climatic conditions, global water scarcity and escalating labor rates, when
the future of rice production is under threat, dry direct seeded rice (DDSR)
offers a viable alternative to PTR. Lack of suitable rice varieties for DDSR
has been a major constraint for adoption in rice growing areas. A successful
transition of rice cultivation from PTR to DDSR will rely on the development
of new nutrient efficient-high yielding climate resilient rice varieties
possessing better adaptability to DDSR.

At International Rice research Institute (IRRI), traits and the QTLs
associated with the traits that increase adaptability to dry direct seeded
cultivation conditions such as root traits [nodal root number (qNR4.1,
qNR5.1) and root hair density (qRHD1.1, qRHD5.1, qRHD8.1)] leading to higher
nutrient availability under dry direct-seeded conditions, early vegetative
vigor (qEVV9.1), early uniform emergence (qEUE1.1, qEUE11.1), and grain
yield under direct-seeded conditions (qGY1.1, qGY8.1, qGY10.1) have already
been identified. The polymorphic markers for early vigor, nodal roots, early
and uniform emergence, drought tolerance, and grain yield under direct
seeding, and gene-specific markers for blast, bacterial blight, and gall
midge have been identified. In this context, a marker-assisted breeding
program combining several genes for biotic and abiotic stresses and traits
required for DDSR situation in many elite genetic backgrounds utilizing
trait linked markers has been initiated at IRRI (Philippines) and Punjab
Agricultural University, Ludhiana (India).



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