SUMMARYFollowing three differing pre-stress temperature treatments, potted plants of three populations of Festuca arundinacea, syn. 1 and syn. 2 (North African) and S. 170 (British) were subjected to a cold stress of 20 h at – 8 °C in a growth cabinet.In all populations, survival was greatest when the cold stress followed continuous low temperatures for 2 weeks, was intermediate after part-day low temperatures for the same period, and poorest after continuous warmth. The hardening response, especially after the fluctuating regime, was greater in S. 170 than in either syn. 1 or syn. 2, between which little difference was detectable.There was no overall difference in survival between spring-sown and autumn-sown material, nor any apparent relationship between survival and relative growth rate.In a further trial, the same three populations were subjected to differing periods of cold stress at — 9 °C-single exposure for 12 or 18 h periods, or one, two or three 6 h periods.The synthetics were progressively weakened by repeated stresses, and were almost completely killed out by 12 or 18 h exposure. Differences in mortality following short and longer periods of exposure were associated with differences in soil temperatures.
Species composition of ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea) mixtures using various combinations of n-alkanes