1Institute of Rice Research and Development Batalagoda, Ibbagamuwa, Sri Lanka.
Department of Botany, University of Kelaniya, Kelaniya, Sri Lanka.
Experiments were carried out in view of, screening rice plants to low light adaptability and studying their response to low irradiance. Nine rice varieties were selected for the study. Selection of varieties was based on their crop duration and yield potential. Of the varieties selected, Bg 300 showed the highest and Vellaikoluban showed the lowest adaptability to low irradiance. A high correlation was observed between the decreasing chlorophyll a/b ratios at low irradiance and the low light adaptability. It has been suggested that a screening method based on this relationship is better than the prevailing methods. Decreasing irradiance reduced the leaf thickness of all the varieties used.
