A gene from wild Indian rice plants can significantly raise the yield of common varieties in nutrient-poor soils.
Scientists from the International Rice Research Institute (Irri) identified a gene that helps uptake of phosphorus, nitrogen and potassium, and transferred it into commercial strains.
Their yield was about 60% above normal in phosphorus-poor soils, the team reports in the journal Nature.
Large swathes of Asia have soil that is phosporus-deficient.
The gene came from a variety called Kasalath, native to nutrient-poor soils of eastern India.
About 10 years ago, scientists deduced that Kalasath contained one or more genes that allowed it to grow successfully in low-phosphorus conditions.
It took the Irri team three years to identify the gene responsible, which they have named PSTOL1.
“We got the [DNA] sequence of this region, but the region is very complex and it was very difficult to identify what is an actual gene and what is not,” lead researcher Sigrid Heuer told BBC News.
“There’s so much work being done on phosphorus pathways and we could never find the genes and the mechanisms, and actually it’s very simple – the gene promotes larger root growth, so the plant takes up nutrients more easily.”
In phosporus-poor soils, PSTOL1 switches on during an early stage of root development.
This increases the area of root in contact with the soil, enabling the plant to scavenge more phosphorus.
Although the researchers focussed on this one key nutrient, they found the faster root growth also helped uptake of nitrogen and potassium, which are also vital for the plant’s development.