Abstract
This study analyzed the contribution of International Rice Research Institute (IRRI) improved germplasm to rice varietal development and yield growth in India. Out of the total of 1436 released high-yielding varieties (HYVs) of rice, 769 (53%) were developed using IRRI improved germplasm at different stages of the breeding cycle. IR8 alone was used 245 times during this period. Most of IRRI's elite lines were used for the improvement of important varietal traits, such as short duration and resistance to biotic stresses. The share of IRRI elite germplasm in all HYVs released in India was 22.8%. The average rice area withIRRI improved germplasm was 16.6% of the total rice area per year from 1966 to 2021. In addition, 11% of rice yield growth was contributed by IRRI improved germplasm each year for the 1966-2021 period. The results indicate that the IRRI-India partnership in germplasm exchange has contributed immensely to rice improvement in India. However, this contribution started declining after 2005, probably due to the strengthening of the national rice research system in India.