This study was conducted to find out indicators to quantitatively evaluate the degree of wear stress on aerial shoots after traffic stress on zoysiagrass collections in South Korea to be used in the school playground. The contents of malondialdehyde (MDA) which may indicate the oxidation degree of cell membrane under stress was correlated with morphological characteristics of zoysiagrass shoots. A wear simulation roll made of aluminum cylinder at 40 kg weight and 1.1 m width with circular studded projections was used to apply artificial traffic stress of pressure and wear for 144 zoysiagrass accessions that had 70% or more of ground coverage. The equipment was driven by the motor at a steady speed rate to reciprocate in the designated potted turfgrass trays in the greenhouse. For morphological characteristics, plant height, leaf length, lowest leaf height, leaf width, leaf angle, stolon length, internode length and diameter of stolon, and stolon node number were investigated. It appeared that there was a statistically significant difference among zoysiagrass accessions in the MDA content, with grouping into 3 categories. From the correlation analysis, the low MDA content group (L) where shoot damage is expected to be relatively weak due to the low degree of stressful oxidation in vivo even after the traffic stress showed thicker node diameter, wider leaf width, longer leaf length, higher plant height and lowest leaf, and narrower leaf angle. Although significantly correlated with those morphological measurements, it was thought that the MDA content alone had a limit to be used as a wear tolerance index.
Figures & Tables
Fig. 1. A moter-driven equipment used for traffic stress treatment in this study.