Mitigation of Drought Stress through the Use of Ethylene Absorbent on Creeping Bentgrass (Agrostis stolonifera) and Annual Bluegrass (Poa annua).

Creeping bentgrass and poa annua are two turfgrass species that are sensitive to drought stress.  How phytohormone profiles (including gibberellic acid, abscisic acid, zeatin riboside, salicylic acid, jasmonic acid, and auxin) of these two species differentially change in response to drought stress is not well-understood. The lack of drought tolerance in poa annua could be related to the hormone profile responses. The objective of this study was to investigate hormone profile changes differentially between poa annua and creeping bentgrass. Also, we tested whether an ethylene absorbent granular product may play a role in promoting drought tolerance in both grass species. The ethylene absorbent was exogenously applied as a granular treatment at the rates of 0.25 and 0.5 g to creeping bentgrass and poa annua under well watered or drought stressed conditions in a controlled environment growth chamber. The effect of ethylene absorbent on growth physiology drought stress response and ethylene evolution of creeping bentgrass and poa annua exposed to drought stress was measured. As expected, the results suggest that creeping bentgrass was more tolerant of drought stress than poa annua. Differential physiological health and hormone profiles will be discussed.