Abstract
Though RGR of rice varieties is influenced to some extent by their LAR at very young stage, it is almost completely governed by their NAR which, in turn, is mainly determined by the mean photosynthetic rate of individual leaves of the plants, displayed by them under the conditions of assemblage in the field, rather than their respiratory activity. And the mean photosynthetic rate of leaves is governed not by their photosynthetic capacity originally they possess, but by the "light-receiving-coefficient" of the assemblage. The coefficient seems to be governed by the number of tillers at very early stage, but, as the assemblage grows thicker, it becomes to be decidedly governed by its total leaf area. Plant height seems to be the second facter influencing the coefficient, , and the thickness of leaves may have some influence on it, too.
