Background:
By 2025, 15-20 million hectares of rice area is predicted to experience severe water constraint/drought. The best method for maximizing rice yields in drought-prone areas is to develop drought-tolerant varieties by introgressing yield QTLs into high yielding popular varieties, which can perform very well under drought stress. IR 64 is very popular rice variety with excellent grain quality with higher market demand in India as well as in aboard with higher export value. Technology Details:
DRR Dhan 42 (RP 5208-3-IR87707-445-B-B-B (IET 22836)) is a Marker Assisted Selection (MAS) derived drought tolerant rice variety developed in the genetic background of popular mega rice variety IR64. It is possessing qDTY 2.2 and qDTY 4.1 QTLs associated with high yield under drought at reproductive and grain filling stages. DRR Dhan 42 has a yield advantage of 19.5% over IR 64. It can yield under irrigated conditions up to 6.5 to 7 t/ha, under moderate drought (25 to 30 rain-free days) upto 3.7 to 4.5 t/ha and under severe drought (>35 rain-free days) 2 to 2.5 t/ha. It is resistant to leaf blast disease. The rice variety DRR Dhan 42 (IET 22836) possesses long-slender grain type with an intermediate amylose content (22.96%) and ASV (4.0) and very occasionally chalky grains were observed, which are similar to its recurrent parent, IR 64. Hence the improved drought-tolerant DRR Dhan 42 will have higher demand in the export market as well as in India.