Biotech Updates

IRRI Scientists Develop Super Salt-tolerant Rice

April 17, 2013

A team of scientists at the International Rice Research Institute (IRRI) developed a new rice line that can drive out salt it takes from the soil into the air through salt glands it has on its leaves. Dr. Kshirod Jena, lead scientist of the team, explained that the "super salt-tolerant rice" variety was developed by crossing two different rice species, the exotic wild rice species Oryza coarctata and rice variety IR56 of the cultivated rice species O. sativa. This is considered a significant breakthrough because it is tricky to cross the wild rice species with cultivated rice varieties. The location of O. coarctata in the rice genome sequence is at the other end of the spectrum from that of rice varieties such as IR56, and thus the embryo tends to abort itself.

The researchers have been trying to backcross the two types of rice because O. coarctata can tolerate water with high salinity (similar to seawater) while the cultivated varieties cannot tolerate such. Finally, the team came up with three embryos after 34,000 crosses. The surviving plant was kept in liquid nitrogen solution and when it was strong enough, it was grown in the field and backcrossed with IR56. The backcrossing ensured that the resulting plant contains all characteristics of IR56 and the desired salt-tolerance trait from the wild rice species. The team will continue to test the new line for the next 4-5 years to make sure that it meets the needs of farmers and consumers.