Effect of Artificial Treading on Morphology and Ethylene Production in Orchardgrass (Dactylis glomerata L.)

Abstract

Morphological response and ethylene production of orchardgrass (Dactylis glomerata L.) were measured under artificial treading during the period from July to November 1993. Plants were grown in stainless steel pots containing autoclaved river sand, which were leached alternatively with distilled water and HOAGLAND'S solution. After the 50th day after sowing, treading treatments (0, 2, 5 and 19 kg/cm^2) were conducted seven times at 5-day intervals. Growth form changed from erect to prostrate type under treading treatments. Plant height was 30-55% lower in the trodden plots and position of shoot apex was 0.35-1.42 mm lower in the trodden plots than those in the control. The number of vegetative tillers was 13-53% more in the trodden plots. Plants produced 43-55 nl ethylene per plant per hour immediately after the first treading treatments of 5-10kgf/cm^2. In these plots, ethylene production decreased on successive sampling dates. Injured rate of tissues, which was estimated from contents of electrolyte leakage, was significantly higher in sheath than in leaf blade, and higher in the trodden plots than in the control. It is suggested that orchardgrass may improve physical stability and tolerance to treading stress under repeated treading treatments.