IRRI Scientists Introduces New Breeding Approach to Harness Genomic Selection in Challenging Environments

by Waseem Hussain, Mahender Anumalla, Margaret Catolos, Joie Ramos, Ma. Teresa Sta. Cruz, and Myrtel Valenzuela

IRRI scientists are changing how rice is bred for stress-prone areas by shifting the focus from traits to environments. Their new approach, TTE, offers a faster, more reliable path to develop climate-resilient varieties.

Scientists at the International Rice Research Institute (IRRI) are shifting the way rice is bred for difficult conditions like drought, salinity, and flooding. Their new approach, called “Transition from Trait to Environment (TTE)”, is changing how breeders think about stress tolerance, not as a trait to be added, but as the very environment where breeding decisions are made.

Traditional breeding methods often start with high-yielding varieties and attempt to add and select for abiotic stress tolerance later. TTE turns this process around. It starts with fixing the stress tolerance in the parental pool, giving breeders a strong foundation from the beginning. This shift improves the accuracy of selection and speeds up the development of varieties suited for challenging environments.

In places where rice farming is threatened by floodwaters or salt-invaded soils, even the best technologies can lose their edge. Genomic selection and population improvement often perform poorly in stressful environments. However, TTE holds steady, with IRRI breeders recording a 65% genetic gain in submergence tolerance in just one cycle. Trials with national partners also showed strong performance from TTE-developed lines in flood-prone areas.