The finding will aid food security for farmers on nutrient-poor land, adding to global production, and help increase their incomes, the Philippines-based IRRI said in a statement.

''The gene–called PSTOL-1, which stands for Phosphorus Starvation Tolerance-1–helps rice grow a larger, better root system and thereby access more phosphorus,'' the institute said.

The institute noted that phosphorus was often locked in the soil, unavailable to plants grown in problematic fields, such as those with acidic soils or upland plots that are not irrigated.

Large areas of Asia have phosphorus-deficient soil, and often farmers are forced to use phosphate-based fertilizers, which have numerous negative impacts on the environment.

The gene was developed from the Kasalath rice variety from India, which grows well in soils low in phosphorus, said IRRI senior scientist Sigrid Heuer, who led the team that published the discovery in the scientific journal, Nature.

''In field tests in Indonesia and the Philippines, rice with the PSTOL-1 gene produced about 20 per cent more grain than rice without the gene,'' she said.

''In our pot experiments, when we use soil that is really low in phosphorus, we see yield increases of 60 per cent and more,'' she added.

The IRRI said scientists in Indonesia were breeding rice plants with the gene and that the new varieties could be available to farmers within a few years.

''The plants are not genetically modified, just bred using smart modern breeding techniques,'' it said.

The finding also shows the importance of conserving genetic diversity of traditional crop varieties, the institute said. It conserves more than 114,000 types of rice in its gene bank. (DPA)