Indias natural rubber yield is estimated at 1,705kg per ha currently, which is the highest in the world.
Productivity in Thailand, the largest producer of natural rubber in the world, is around 1,418 kg per ha.
Mr Mathew said the institute has been working on the new rubber varieties for the last 22 years and they are now ready for distribution to farmers for commercial use. The project to develop the clones was launched as early as 1983, he said. By 1993, the institute had developed five new high-yielding clones.
Of these, two clones 414 and 430 were found to be the most promising during the experimental programs conducted by the institute.
These two varieties have the ability to increase the yield by 15% to 40% per hectare, Mr Mathew said adding they have also been found to mature early.
At present, the rubber plant reaches tapping age in the seventh year, while the new varieties are found to be ready for tapping in six-and-half years. Meanwhile, President APJ Abdul Kalam will on Friday launch the golden jubilee celebrations of the Institute in Kottayam, Kerala.