Electrolyte Leakage as an Indicator of High-temperature Injury to Harvested Mature Green Tomatoes

Abstract

Newly harvested tomatoes are often exposed to short periods of high temperatures. To simulate harvest conditions, mature green (MG) tomatoes (Lycopersicon esculentum Mill., cv. 908) were exposed to direct solar radiation until their mean temperatures became 45°, 50°, or 55°C. When fruit temperatures were > 50°, heat injury was obvious. Once exposed, tomatoes remained at these high temperatures for ≈ 1 hr, even after being transferred to shade. The interaction between high temperature and exposure time on tomato thermostability was studied in the laboratory. MG ‘908’ tomatoes were exposed to temperatures ranging from 25° to 65° for 30 to 180 min; the damage was then measured by determining the amount of electrolyte leakage. A mathematical model describing the interaction of temperature and time was used to predict the critical high temperature and exposure time. Critical exposure times calculated for ‘908’ tomatoes were 34, 105, and 166 min for exposure to 55°, 50°, and 45°, respectively. For practical field applications, this high-temperature stress may decrease the quality by causing the destruction of fruit cellular tissue and physiological disorders.

The Role of Antioxidative Enzymes in Tomato Leaves Under Heat Stress at Two Developmental Phases

“…Ion leakage is a common evaluation way for cell membrane thermostability and a valuable criterion for heat tolerance in selecting heat tolerant plants (Inaba and Crandall, 1988;Kesici et al, 2013;Din et al, 2015). Electrolyte leakage is affected by the age, sampling part, development period, growing season, hardening and species of plant (Wahid et al, 2007).…”

“…Plant acclimation to moderately high temperature has significant effect on inducement of tolerance to lethal high temperatures (Hasanuzzaman et al, 2013). Estimation of cell membrane stability under heat stress is used to express stress tolerance in various plant species including tomato (Inaba and Crandall, 1988;Cansev, 2012;Kesici et al, 2013;Din et al, 2015;Jahan et al, 2019). In addition, heat stress causes the production of highly reactive and toxic superoxide (O2 •-), singlet oxygen ( 1 O2), hydrogen peroxide (H2O2) and hydroxyl radicals ( • OH) known as reactive oxygen species (ROS) which causes oxidative stress by damaging proteins, lipids and carbohydrates (Suzuki and Katano, 2018;Cohen et al, 2021).…”

Resilience of hop (Humulus lupulus L.) to salinity, heat and drought stresses: A mini-review

“…The disruption of membrane fluidity caused by heat, also, determines the breakdown of the thylakoid membrane integrity, which leads to disruptions in the electron transport chain and ATP synthesis ( Gounaris et al., 1983 ; Inaba and Crandall, 1988 ). Moreover, HT stress was found responsible for the destruction of the Rubisco activase protein, leading to the inactivation of the carboxylating enzyme and, therefore, to the disruption of carbon assimilation ( Salvucci et al, 2001 ; Salvucci and Crafts-Brandner, 2004 ; Sharkey, 2005 ).…”