Vernalization of Crops Cultivated in India

Photoperiodism in Rice

“…Sircar & Parija (1949), however, could not get any delaying effect in Jhanji 34 and Bhutmari 36, two other Bengal summer varieties by giving similar treatments. Kar (1946) by giving long and short days separately for 15 days to two early (summer) and eight late (winter) varieties of Bengal rice, made a general statement that in different varieties of paddy high temperatures associated with short daylengths were conducive to earliness, and low temperatures or longer daylengths produced retardation. In these four early varieties of rice, as also in the three medium early varieties T. 3, T. 12, T21 of Uttar Pradesh (Misra, 1953) grown throughout their life period under naturally prevailing warm temperature, short days did not induce earliness but rather they greatly prolonged the time of ear emergence, which indicates that Kar's generalization needs modification.…”