Tolerance performance of the cool-season turfgrass species Festuca ovina, Lolium perenne, Agrostis tenuis, and Poa trivialis to sulfur dioxide stress

Abstract

Tolerance of four cool-season turfgrass species sheep fescue (Festuca ovina), perennial ryegrass (Lolium perenne), colonial bentgrass (Agrostis tenuis) and rough bluegrass (Poa trivialis) to SO2 was studied by investigating their injury and physiological responses under SO2 stress for 14 days. Results showed that sheep fescue and perennial ryegrass had better SO2 tolerance than rough bluegrass and colonial bentgrass. Chlorophyll a and carotenoid contents were significantly higher in the SO2-tolerant turfgrass species (sheep fescue and perennial ryegrass) than in the SO2-sensitive turfgrass species (rough bluegrass and colonial bentgrass). Relatively lower levels of reactive oxygen species (ROS), malondialdehyde, and electrolyte leakage (EL) were observed in SO2-tolerant turfgrass species. Gradually increased antioxidant enzyme activities and proline content in SO2-tolerant turfgrass species could counteract such damages and harmful effects caused by ROS and EL, respectively. Sulfite reductase played an important role in sulfur metabolism and subsequently reduced oxidative pressure on SO2-tolerant turfgrass species.