Crop Physiology Research Unit, University College of Agriculture, Calcutta University, Calcutta-700019.
The success of hybrid rice programme in this country presupposes identification and selection of potential elite rice cultures having wide plasticity in days to flower. The results indicate the vulnerability of the three elite cultures e.g. IET 13501, IET 13490 and Pranava to daylength, in terms of flowering. It is suggested that even in the cultures under study, flowering was brought about by a combination of either a relatively lower summation of day degree and relatively longer days. Irrespective of the date of planting, flowering in the elite rice cultures seems to occur under a number of combinations of temperature and daylength conditions.
