A COMPARISON OF NEGATIVE RELATIVE GROWTH RATES IN SHADED SEEDLING

Abstract

Seedlings of the shade‐tolerant species, Deschampsia flexuosa, were subjected to shade treatments under controlled conditions of daylength, temperature, irradiance, relative humidity and mineral nutrient supply. Dry matter production was compared with that of seedlings of the shade‐intolerant species, Agrostis tennis and Festuca ovina. The three species did not differ markedly with respect to their light intensity compensation points. A more promising explanation for the shade tolerance of Deschampsia flexuosa lies in the extremely low negative relative growth rates which seedlings exhibit at light intensities below the compensation point. Copyright © 1974, Wiley Blackwell. All rights reserved