Zahra Sadat Amiri; Zahra Pakkish; Fatemeh Nasibi
Abstract
In this study, we evaluated the effects of selenium nanoparticles on chilling injury and improving the shelf life of Valencia orange (Citrus sinensis) fruit. Treatments included 0.5 and 1 mg L-1 selenium nanoparticles, with three replicates per treatment and six replicates in total. Statistical analyses ...
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In this study, we evaluated the effects of selenium nanoparticles on chilling injury and improving the shelf life of Valencia orange (Citrus sinensis) fruit. Treatments included 0.5 and 1 mg L-1 selenium nanoparticles, with three replicates per treatment and six replicates in total. Statistical analyses were performed using SPSS, with data analyzed by one-way ANOVA and mean separations by Duncan’s new multiplerange test. Results showed that samples treated with selenium at 0.5 and 1 mg L-1 significantly decreased lipid peroxidation (55 and 62%, respectively) compared to control samples. Selenium treatments also in creased the activity of antioxidant enzymes, including CAT (twice and four times), peroxidase (2.5 and 4 times), APX (about 0.5 and 2.5 times), and SOD (by 4 and 6 times), with consistent results in DPPH radical scavenging (by 2.5 and 3.5 times) in the orange fruits. Selenium at both concentrations effectively reduced the incidence of chilling injury in Valencia orange fruits during six months of storage at 3 °C. Chilling injury was best reduced at 1 mg L-1. This study proved that selenium can enhance orange fruit quality and increase its tolerance to cold storage conditions, potentially leading to selenium-enriched fruits with health benefits for consumption.
Fatemeh Nasibi; Khosrow Manouchehri Kalantari; Zahra Manzari Tavakoli
Abstract
One of the major abiotic stresses limiting the productivity and the geographical distribution of many important crops is low temperature. Hydrogen sulfide (H2S) is an important signaling molecule involved in several stress-resistance processes such as drought, salinity and heavy metal stresses in plants. ...
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One of the major abiotic stresses limiting the productivity and the geographical distribution of many important crops is low temperature. Hydrogen sulfide (H2S) is an important signaling molecule involved in several stress-resistance processes such as drought, salinity and heavy metal stresses in plants. The aim of this study was to investigate the effects of exogenous H2S on improving chilling tolerance of cucumber seedlings. The results indicated that seedlings exposed to chilling stress (4 ºC) increased the level of electrolyte leakage, lipid peroxidation, hydrogen peroxide, proline content and guaiacol peroxidase (GPX) activity; while sugar soluble content decreased. Pretreatment with sodium hydrosulfide (NaHS), a hydrogen sulfide donor, slightly reduced the malondialdehyde content, hydrogen peroxide content and electrolyte leakage, which were induced by chilling stress and also elevated the activity of antioxidant enzymes, soluble sugar and proline levels, and reduced glutathione content in plants under chilling stress condition. Pre-treatment with other Na+ and sulfur-containing components including Na2S, Na2SO4, Na2SO3 showed no significant effect on lipid peroxidation and hydrogen peroxide content under chilling stress. It can be concluded that the effect of NaHS pretreatment on alleviation of cold stress damages is probably related to its ability to release H2S because Na+- or sulfur-containing compounds (except NaHS) had no similar effects on alleviation of chilling damages.
Ghader Habibi
Abstract
Salicylic acid (SA) plays an important role in the regulation of plant ripening and responses to abiotic stresses. In this study, the protective effect of SA on cold stress-caused oxidative damage in grape (Vitis vinifera L.) bunches was investigated during cold storage. Grape bunches treated with ...
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Salicylic acid (SA) plays an important role in the regulation of plant ripening and responses to abiotic stresses. In this study, the protective effect of SA on cold stress-caused oxidative damage in grape (Vitis vinifera L.) bunches was investigated during cold storage. Grape bunches treated with 2 mM SA and stored at 0°C with 85-90% RH for 30 days. Samples were selected from each treatment for physical and chemical analysis before storage, midpoint of storage, end of storage and end of shelf life. The results showed that the cold storage induced lipid peroxidation, decay incidence and loss of fresh weight, while SA pretreatment mitigated these effects in “Bidaneh Sefid” and “Qzl uzum” cultivars. In these cultivars, SA-induced protection against cold damage was accompanied by decrease in malondialdehyde (MDA) content, and caused an increase in catalase (CAT) and superoxide dismutase (SOD) activity. Additionally, SA-induced protection against cold injury was mediated through promoting total phenolics concentration and phenylalanine ammonia-lyase (PAL) activity. The present findings suggest that although variability in the protective effect of SA against cold damage was observed between grape cultivars, SA could alleviate the cold-induced oxidative stress in grape bunches during cold storage.