γ-Aminobutyric acid treatment induced chilling tolerance in postharvest peach fruit by upregulating ascorbic acid and glutathione contents at the molecular level

Abstract

Peach fruit was treated with 5 mM γ-aminobutyric acid (GABA) to further investigate the mechanism by which GABA induced chilling tolerance. Here, we found that GABA not only inhibited the occurrence of chilling injury in peach fruit during cold storage but also maintained fruit quality. Most of the ascorbic acid (AsA) and glutathione (GSH) biosynthetic genes were up-regulated by GABA treatment, and their levels were increased accordingly, thus reducing chilling damage in treated peaches. Meanwhile, the increased transcript of genes in the AsA-GSH cycle by GABA treatment was also related to the induced tolerance against chilling. GABA treatment also increased the expression levels of several candidate ERF transcription factors involved in AsA and GSH biosynthesis. In conclusion, our study found that GABA reduced chilling injury in peach fruit during cold storage due to the higher AsA and GSH contents by positively regulating their modifying genes and candidate transcription factors.

Antioxidant Systems and Quality in Sweet Cherries Are Improved by Preharvest GABA Treatments Leading to Delay Postharvest Senescence

“…Taking into account the results of all these quality parameters, control cherries could be stored at cold temperatures for two weeks with optimal properties for consumption, while this period was extended to up to four weeks for cherries from the 50 mM GABA-treated trees. Postharvest GABA dipping treatments have been proven to successfully maintain fruit quality properties in cornelian cherry [ 28 ], loquat [ 31 ], peach [ 29 ] and tomato [ 38 ], with additional effects on reducing chilling injury symptoms. Moreover, other postharvest treatments with effects on maintaining fruit quality, such as sodium nitroprusside (SNP) in peach [ 39 ], calcium in apple [ 40 ] or melatonin [ 41 ] and methyl jasmonate [ 42 ] in tomato, increased GABA content and the GABA-shunt pathway, proving the effects of GABA on delaying the postharvest ripening and senescence processes, which has been attributed to an enhanced mitochondrial energy status [ 29 ].…”

“…Postharvest GABA dipping treatments have been proven to successfully maintain fruit quality properties in cornelian cherry [ 28 ], loquat [ 31 ], peach [ 29 ] and tomato [ 38 ], with additional effects on reducing chilling injury symptoms. Moreover, other postharvest treatments with effects on maintaining fruit quality, such as sodium nitroprusside (SNP) in peach [ 39 ], calcium in apple [ 40 ] or melatonin [ 41 ] and methyl jasmonate [ 42 ] in tomato, increased GABA content and the GABA-shunt pathway, proving the effects of GABA on delaying the postharvest ripening and senescence processes, which has been attributed to an enhanced mitochondrial energy status [ 29 ]. It is important to note that consumers have concerns about post-harvest fruit treatments, which have also more legal restrictions than preharvest ones; meanwhile, preharvest treatments with GABA, which is a natural amino acid, are considered to be safe and to have beneficial properties for human health [ 43 ], so this could be a suitable and environmentally friendly approach to increase sweet cherry quality and their storage time for longer periods.…”

“…In addition, the GABA shunt plays important roles in reducing reactive oxygen species (ROS) and acting as a signaling molecule regulating several stress-related mechanisms [ 25 , 26 ]. More recently, beneficial effects of postharvest fruit GABA treatments on maintaining quality properties and reducing chilling injury damage have been reported in a wide range of fruit species, such as table grape [ 27 ], cornelian [ 28 ], peaches [ 29 ], mango [ 30 ], loquat [ 31 ] and kiwifruit [ 32 ], among others.…”

Participation of γ-aminobutyric acid in cell signaling processes and plant adaptation to abiotic stressors

“…Нині ж дослідники динамічно накопичують нові знання про регуляторні функції ГАМК у рослин (Suhel et al, 2023a), інтенсивно досліджують вплив екзогенної ГАМК на стійкість рослин різних таксономічних груп до різних типів стресових факторів. Виявлені феномени стосуються і стійкості рослин до дії низьких (Mazzucotelli et al, 2006;Zhou et al, 2022) та високих (Bhardwaj et al, 2021;Zeng et al, 2021) температур і посухи (Farooq et al, 2017;Zhou et al, 2021;Zhao et al, 2023).…”

“…Наприклад, виявлено, що підживлення незагартованих рослин пшениці глутаматом, який є субстратом для синтезу ГАМК, призводило до зростання її вмісту за подальшої дії низької температури і сприяло підвищенню стійкості (Mazzucotelli et al, 2006). Обробка плодів персика ГАМК за низькотемпературного зберігання підвищувала їхню холодостійкість, сприяючи зростанню активності й експресії генів СОД, КАТ, АПО, глутатіонпероксидази, глутатіон S-трансферази, МДГАР і ДГАР (Zhou et al, 2022).…”