Light Interception, Photosynthetic Activity, and Crop Growth Rate in Canopies of Six Temperate Forage Grasses

Abstract

distribution in the canopy in relation to light interception and also by the photosynthetic activity of the individual leaves. The primary aim of this paper is to investigate the effect of leaf arrangement and the optical properties of contrasting forage grass canopies on their crop growth rates and the relative importance of leaf arrangement and individual leaf photosynthesis in determining crop growth rate. A secondary aim was to use the data collected to examine the value of certain theoretical models in simulating the growth of these canopies, and hence, enabling the plant breeder to predict the consequences of selecting for particular morphological or physiological characters of the plant. The characters examined included the light distribution within the canopies, a survey of the LAI profiles, the angular distribution and optical properties of the individual leaves, and the relation between individual leaf photosynthesis and illumination.