1c:I[419806,["/_next/static/chunks/bb923814e1f4d2e9.js","/_next/static/chunks/dd3ee9f5b7716ca6.js","/_next/static/chunks/4204a0ae82542ca8.js","/_next/static/chunks/30036bedc5269936.js","/_next/static/chunks/6e1aa89a642f40be.js","/_next/static/chunks/cd5e572bc3e4eb92.js","/_next/static/chunks/8ffd0b71567920d8.js","/_next/static/chunks/67ea6dfd21f16c5f.js","/_next/static/chunks/24eb4379f68013fd.js","/_next/static/chunks/b8cd775ffdf935bd.js","/_next/static/chunks/983103cd9eb7b428.js","/_next/static/chunks/d4ac9dcf27f6ff52.js","/_next/static/chunks/294b9525248c8e5f.js"],"default"] 1d:T510,Temperature stress can have a devastating effect on plant metabolism, disrupting cellular homeostasis, and uncoupling major physiological processes. A direct result of stress‐induced cellular changes is the enhanced accumulation of toxic compounds in cells that include reactive oxygen species (ROS). Although a considerable amount of work has shown a direct link between ROS scavenging and plant tolerance to temperature stress, recent studies have shown that ROS could also play a key role in mediating important signal transduction events. Thus, ROS, such as superoxide (O 2 – ), are produced by NADPH oxidases during abiotic stress to activate stress‐response pathways and induce defense mechanisms. The rates and cellular sites of ROS production during temperature stress could play a central role in stress perception and protection. ROS levels, as well as ROS signals, are thought to be controlled by the ROS gene network of plants. It is likely that in plants this network is interlinked with the different networks that control temperature stress acclimation and tolerance. In this review paper, we attempt to summarize some of the recent studies linking ROS and temperature stress in plants and propose a model for the involvement of ROS in temperature stress sensing and defense.1e:T4e5,A method for assessing frost hardiness of plant tissues [using shoots of Picea rubens Sarg. syn P. rubra (Du Roi) Link] has been developed based upon the rate of electrolyte leakage from shoots immersed in distilled water after exposure to a range of freezing treatments. The relationship between conductivity (the electrolyte concentration in solution) and time has been shown to follow an asymptotic curve, which may be represented by a first-order equation: C_t -C_o = C_auto -C_o - C_-kt ) where C₁ is the conductivity at time t, C_o is the initial conductivity, C_auto is the conductivity after autoclaving and k is the first-order rate constant (units time^-1 ). The rate of electrolyte leakage (k) varies directly with the extent of tissue damage. In P. rebens a rate of 0-4%, h^-1 distinguished between shoots which eventually died, and shoots which remained alive. A minimum of 3 conductivity measurements (after 1 day, 5 days and after autoclaving) is required for a reliable estimate of k. This objective, quantitative method of assessing frost hardiness may therefore be used directly to estimate LT₅₀ values within a population.

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