Physiological response of warm-season turf-grass to high temperature stress

An experiment was conducted to determine physiological responses of Zoysia matrella and Z. japonica to high temperature stress. The results show that the contents of soluble sugar and protein, proline, ABA, GA3, IAA and MDA increase in two tested turf-grass species, along with increased SOD, POD and CAT activity under high temperature stress. High temperature stress treatment decreases chlorophyll a (Chla), chlorophyll b (Chlb) and carotenoid (Car) content, and it concurrently induces changes in leaf Chla/Chlb ratio in the two turf-grass species. The contents of the osmotic adjustment substances, ABA, GA3 and IAA are higher in Z. matrella than in Z. japonica. The same is true for SOD and CAT activity in the two turf-grass species when exposed to high temperature treatment. Hence Z. matrella exhibits better heat resistance than Z. japonica under high temperature conditions.