Growth and Photosynthetic Response of Lawn Grass under Low Light Conditions

Abstract

An experiment was conducted on the growth and photosynthetic response of seven kinds of lawngrass under low light conditions. The environmental conditions were controlled such that the air temperature was 20±2°, relative humidity was 75±10%, and day light lasted for 12 hours. The following results were obtained:
(1) Under a photosynthetically available radiation of 2.42 μmol·m^-2·s^-1, all kinds of lawn grass withered. Under a photosynthetically available radiation of 7.86 μmol·m^-2·s^-1, Stenotaphrum secundatum Variegatum.(variegated leaf), Poa pratensis L. and Eremochloa ophiuroides Hack. remained alive. Under a photosynthetically available radiation of 73.84 or 164.77 μmol·m^-2·^s-1, all seven kinds of lawn grass grew favorably.
(2) As the photosynthetically available radiation was increased from 2.42 μmol·m^-2·s^-1 to 164.77 μmol·m^-2·s^-1, the dry weights of the terrestrial parts of all seven kinds of lawn grass increased.
(3) Relation between photosynthetically available radiation and photosynthetic rate of seven kinds lawn grass was as follows:
Zoysia matrella Merr.: Y=-2.2736+0.0328x r=0.765/Eremochloa ophiuroides Hack.: Y=-0.6195+0.0436x r=0.936/Stenotaphrum secundatum Kuntze.(green leaf): Y=-0.5029 +0.0372x r=0.977/Stenotaphrum secundatum Variegatum.(variegated leaf): Y=-0.06061+0.0208x r=0.852/Lo/ium perenne L.: Y=-7.5256 +0.231x r=0.883/Poa pratensis L.: Y=-1.2378 +0.096x r=0. 687/Festuca rubla L.: Y=-1.9379+0.059x r=0.833