ESTIMATION OF YIELD IN WHEAT FROM MEASUREMENTS OF PHOTOSYNTHESIS AND TRANSLOCATION IN FIELD

The rate of photosynthesis of ears, flag leaves and second leaves of two varieties of wheat, and the proportion of synthesized carbohydrate translocated from them to the grain, were determined in the field using 14CO2. The relationship of rate of photosynthesis to changes in age and in incident radiation was expressed by parameters determining hyperbolic functions. These were combined with empirical equations describing the increase with age in the proportion of photosynthate stored in the grain, to form a mathematical model by which yield was determined from physiological parameters. This model gave estimates of yield in reasonable agreement with measured values. Copyright © 1969, Wiley Blackwell. All rights reserved