Growth and behavior of photosynthesized¹⁴C in various crops in relation to productivity

Abstract

1) Rice, spring wheat, maize, soybean, field bean, potato and sugarbeet were grown in Hokkaido with good management, and the difference in economic yield among these crop species was discussed on the basis of differences in growth duration, crop growth rate, and behavior of uC assimilated at different growth stages.2) Tbe economic yield is higher in maize, potato and sugarbeet than in other crops.Tbe high yield is due to a high photosynthetic rate per unit leaf area in maize, to a high sink capacity of the tubers in potato, and to a long growth duration of the leaves as weil as the tap.root in sugarbeet.3) Tbe economic yield is lower in spring wheat, soybean and field bean.Tbe low yield is due to a short growth duration in spring wheat, and to an unfavorable leaf display and a large respiratory loss of photosynthates during grain ripening to produce proteins and lipids in Leguminosae crops.