Effects of differences in light intensity and temperature on the anatomy and development of leaves of lolium perenne and paspalum dilatatum

Abstract

Abstract Plants of Lolium perenne and Paspalum dilatatum, which were germinated under uniform conditions, were grown subsequently under two contrasting conditions of light and temperature∶ (a) full daylight at a mean temperature of approximately 14°c,(b) shading to 20% of daylight at a mean temperature of approximately 24 °c. At the time the fifth leaf had emerged some of each set of plants were transferred to the contrasting conditions. Under shading at higher temperature, early formed leaf blades were approximately twice the length and half the width of those matured in full daylight at the lower temperature and differences of similar magnitude were present in subsequently formed leaves. However, in plants for which the treatments were later reversed, leaves which had begun to elongate beyond the stem apex at the time of reversal finally had dimensions similar to those of leaves formed and grown to maturity under the contrasting conditions. From these various results it was d...