Biotech Updates

Development of 3rd Generation Climate Resilient and Dry Direct Seeded Rice Varieties

November 28, 2018

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).

The study conducted by Nitika Sandhu and colleagues was published in the Journal of Experimental Botany. Read the abstract for more details.