Selenium Improves Physiological Parameters and Alleviates Oxidative Stress in Strawberry Seedlings under Low-Temperature Stress

Abstract

Here, we investigated the effects of selenium (Se) applications on two strawberry varieties, Akihime and Benihoppe, under chilling stress and recovery conditions. Changes in photosynthetic parameters, antioxidant enzyme activities, ascorbate (AsA)-glutathione (GSH) cycle-related enzyme activities, and low-molecular-mass antioxidant contents were determined. Foliar spraying with Se alleviated the decline in the net photosynthetic rate and chlorophyll content and increased the malondialdehyde and hydrogen peroxide contents of strawberry seedlings’ leaves under chilling stress. As the time under chilling stress increased, the stomatal conductance decreased and intercellular CO2 concentration increased, suggesting that nonstomatal factors had major limiting effects on the net photosynthetic rate’s decrease. Se applications significantly alleviated the adverse impacts of chilling stress on changes in stomatal conductance and intercellular CO2 concentration. Se, especially at lower concentrations, significantly increased superoxide dismutase, catalase, and peroxide enzyme activities during chilling stress. Approximately 5 mg·L−1 of sodium selenite solution had the greatest stress-alleviating effects. Among the AsA-GSH cycle-related enzymes, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase (MDHAR) treatments, coupled with an appropriate dose of Se, significantly enhanced ascorbate peroxidase and MDHAR activities, which suggested that Se applications played important roles in strawberry leaves by affecting AsA-GSH cycle-related defenses against the oxidative damage caused by chilling stress. Furthermore, MDHAR was the key enzyme required to maintain the balance between AsA consumption and regeneration that may assist in protecting strawberry seedlings in a low-temperature environment.

Modulation of ascorbate-glutathione cycle by selenate and sulphate treatments in the seedlings of two rice (Oryza sativa L.) cultivars

“…khitish with an increase in selenate concentrations. This is in line with results obtained in rocket tops and strawberry seedlings (42,46). Greater increments in APX activity in both root and shoot of cv.…”

Selenium and Nano-Selenium Biofortification for Human Health: Opportunities and Challenges

“…The most important nutrients that have been investigated in several biofortification studies include calcium [106], iron [92,107], copper [108], zinc [109][110][111], iodine [29,92], potassium [112], and selenium [66,113]. The use of Se fertilizers is one of the most common methods for Se-biofortification of several crops [105], such as rice [113][114][115], maize [116,117], wheat [92,111,118], cowpea [119], potato [85,120], carrot [90,121], turnip [122,123], shallot [124], beans [125], lettuce [91,126], basil [127], strawberry [32,33], and apple [128,129]. Edible plants that have been biofortified with Se [105] or livestock fed selenium-enriched alfalfa [25,130] are used to support human health as reported by the Finnish experience in biofortification with Se through fertilizers.…”

“…Plant related soil and environmental stresses include salinity, drought, waterlogging, heat, and heavy metal stress, which represent serious constraints for global crop productivity [109]. Heavy metals and potential toxic trace metals that may exist in soil include arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and selenium, which can be introduced into the soil through human activities such as mining [176], industrialization [177], urbanization [33], and agricultural practices [178,179]. These metals can also naturally occur in soils at levels that may cause problems [28,105].…”

“…Crops grown in Se deficient soils can be biofortified, including the use of both soil-based and foliar fertilizers to correct the deficiency [27]. Food crops that are commonly biofortified include cereals [29], leafy vegetables like spinach [30] and lettuce [31], and fruits like strawberry [24,32,33] and pomegranate [23]. Due to their lower toxicity, strong capacity to scavenge free radicals, higher bioavailability, and stimulation effect, Se-NPs have been recently used in the production of plants [23,24,[34][35][36], fish [37][38][39][40], livestock [41], and poultry [42][43][44][45][46][47][48].…”

“…The most important studies investigating Se and its role under Cd stress on rice plants include the application of Se to mitigate Cd accumulation in high-Cd-contaminated soils [192], the behavior of Se at different planting times [115], the effects of Se-forms and application methods on modulation of rice growth [83], how Se reduces the uptake and translocation of Cd from contaminated soils [193], and reducing oxidative stress induced by Cd [33,[194][195][196][197][198]. 4.…”