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.
Fariba Bagheri; Abdolhosein Rezaei Nejad; Mohammad Reza Raji
Abstract
Waterlogging may be imposed by intense rainfall, excessive irrigation, or poor drainage. In Iran, besides the northern parts of the country with high precipitation, waterlogging may occur due to over-irrigation, or inadequate drainage especially for landscape use of ornamentals. In this study, the joint ...
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Waterlogging may be imposed by intense rainfall, excessive irrigation, or poor drainage. In Iran, besides the northern parts of the country with high precipitation, waterlogging may occur due to over-irrigation, or inadequate drainage especially for landscape use of ornamentals. In this study, the joint effects of growth stage (four-leaf stage, full growth and start flowering), at which waterlogging is encountered, and the duration of the episode (0, 6, 12, and 24 h) on flowering induction, plant growth, and external quality were investigated in zinnia (Zinnia elegans Jacq.). Waterlogging generally downgraded visually-perceived quality (stem length, flower size, leaf coloration), increased the risk of buckling (lower stem strength) and shortened flower bud longevity. Waterlogging adversely affected biomass accumulation, through decreases in both light capture (leaf area), and photosynthesis. Besides disturbed water relations, waterlogged plants underwent oxidative damage as indicated by reduced chlorophyll content, and elevated lipid peroxidation level. Waterlogging was further associated with increased activity of antioxidant enzymes (ascorbate peroxidase, peroxidase). The waterlogging-induced effects were generally more prominent as waterlogging duration increased, and the growth stage of application was less advanced, so that the plants waterlogged in four-leaf stage for 24 h showed the most negative effects and their plant dry weight reduced to 75 percent of that in controls. In conclusion, the obtained results offer a quantitative analysis of how both growth stage and duration determine the waterlogging-induced injury in zinnia.
Fatemeh Heidarian; Parto Roshandel
Abstract
To evaluate the effect of salicylic acid (SA) on seed germination of black bean plant under saline conditions, seeds were primed with salicylic acid (0, 2, 10, and 20 mM) and germinated under salt stress (0, 50, and 100 mM NaCl). The measured parameters included the percentage and rate of seed germination, ...
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To evaluate the effect of salicylic acid (SA) on seed germination of black bean plant under saline conditions, seeds were primed with salicylic acid (0, 2, 10, and 20 mM) and germinated under salt stress (0, 50, and 100 mM NaCl). The measured parameters included the percentage and rate of seed germination, seedling length and dry weight, malondialdehyde and hydrogen peroxide levels, and activity of catalase, ascorbate peroxidase and guaiacol peroxidase in the seedlings. Results showed the values of germination indices decreased with increasing the level of salt stress. However, SA priming (10 mM) alleviated the harmful effects of salt stress in black bean. SA increased seed germination percentage by 72% and 45% at 50 and 100 mM NaCl respectively, compared to the control condition. Germination rate augmented by 33% (at 50 mM NaCl) and 60% (at 100 mM NaCl) by SA priming compared to the seeds exposed to salt stress alone. Seedlings dry weight (+ 51% at 50 mM and + 34% at 100 mM) and length (+ 57% at 50 mM and + 29% at 100 mM NaCl) were significantly higher by priming with 10 mM salicylic acid, compared to exclusively salt stress-treated seeds. SA priming increased antioxidant enzymes activities and decreased the levels of lipid peroxidation and hydrogen peroxide in salt stressed black bean seedlings. In conclusion, salicylic acid priming (particularly at 10 mM) enhances salt tolerance in black bean via lessening of oxidative stress.