Rice production in the rainfed shallow lowlands in the eastern region and the favorable shallow lowlands in the southern region of India has, for a long time, remained stagnant. The potential of high-yielding varieties is not fully realized. Several breeding lines are being evaluated every year in these ecosystems in trials organized under the All India Coordinated Rice Improvement Program (AICRIP). When compared with national checks Salivahana and Pranava, none could qualify for release in favorable shallow lowlands in the southern region. However, in the rainfed shallow lowlands of the eastern region, CR1002 (1992) and Pooja (1999)were released for cultivation. This shows that yield improvement per se of varieties bred for these ecosystems, especially in favorable shallow lowlands, is limited, though improvement was considerable in quality and pest resistance as reflected by the release of several varieties at the state level.