Author: Apurvbharati Hareshbharati Goswami
Goswami, Apurvbharati Hareshbharati, 2024 Investigating effect of ethylene pre-treatment on seed to enhance heat stress tolerance in wheat, Flinders University, College of Medicine and Public Health
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Extreme high temperatures have become more common due to global warming posing considerable difficulties to plant growth and agricultural productivity. High temperature is one of the most damaging abiotic stresses to crop growth and production, requiring appropriate mitigating techniques. This study looks at how ethylene pre-treatment affects growth and heat stress responses in two wheat cultivars (Scepter and E60) using ethephon for seed priming. We investigated biomass accumulation, oxidative stress markers (malondialdehyde (MDA) levels) and metabolic changes (gamma-aminobutyric acid (GABA) and starch content) under both optimum (17°C) and heat stress conditions (27°C for up to 144 hours). Ethephon pre-treatment with 5μM significantly increased biomass accumulation in both wheat varieties. Furthermore, short-term heat stress enhanced antioxidant defences in ethylene pre-treated plants as demonstrated by lower MDA level indicators of oxidative stress. However, prolonged heat stress (144 hours) increased MDA accumulation indicating that ethylene protective effects may be restricted during a lengthy duration of stress. Furthermore, ethylene priming was found to increase GABA concentration during heat stress, demonstrating its involvement in stress tolerance mechanisms. Ethephon pre-treatment also helped to stabilise starch levels during heat stress indicating increased metabolic activity. These findings emphasise the complexities of ethylene-mediated responses in wheat which are significantly impacted by genotype. This work highlights the efficacy of ethylene-based seed priming as a feasible approach to enhance heat stress tolerance in wheat. It promotes cultivar-specific optimisation strategies to improve the effectiveness of ethylene treatments. This study offers significant insights into wheat's physiological and biochemical reactions to heat stress, facilitating future studies focused on establishing sustainable agricultural methods in the context of climate change problems.
Keywords: ACC, ETH, GABA
Subject: Biotechnology thesis
Thesis type: Masters
Completed: 2024
School: College of Medicine and Public Health
Supervisor: Dr Sunita Ramesh