Chemical priming to improve annual bluegrass survival of ice encasement

Abstract

Broadly applicable management strategies to prepare turfgrasses for overwintering are lacking. This research aimed to investigate whether chemical priming in the field may improve the survival of the perennial form of annual bluegrass (Poa annua L.) after ice encasement. Annual bluegrass field plots were treated in the summer and fall of 2017 and 2018 with salicylic acid (SA), jasmonic acid (JA), trinexapac-ethyl (TE), Civitas (active ingredient: mineral oil), and combinations of each chemical or were not treated. Civitas and Civitas + TE-treated plants had the highest level of turfgrass quality throughout the summer and fall. Normalized difference vegetative index (NDVI) and dark green color index (DGCI) indicated that JA + TE and Civitas + TE had consistently higher values than controls on many dates. Plant plugs were transferred from the field to a low temperature growth chamber (-4 • C) for ice encasement or no ice treatment. Following ice encasement for 40 or 80 d, all treatments except for TE alone showed some significant improvements in annual bluegrass recovery. Treatment of annual bluegrass in the summer and fall with Civitas, TE + Civitas, JA, and TE + JA preceding ice encasement may improve recovery from prolonged ice encasement and be useful turf management practices. Without ice encasement at low temperature, Civitas was the only treatment that improved recovery. The chemical treatments that improved ice encasement recovery may alter annual bluegrass fatty acid ratios, such as by increasing the unsaturated fatty acid, linoleic acid.

Current Outlook on Ice Encasement Stress and Management Strategies in Turfgrasses

“…Little information exists to answer this question. Priming agents such as jasmonic acid alone or in combination with a mineral oil product (Civitas) or trinexapac-ethyl aided annual bluegrass in ice encasement recovery (Laskowski and Merewitz, 2020b). Priming agents in combination with trinexapac-ethyl, which was previously thought to possibly reduce ice encasement tolerance, showed enhanced regrowth following ice encasement.…”