Abstract:
To investigate the effects of exogenous trehalose on strawberries under low-temperature stress,'Benihoppe' strawberry was used as the experimental material in this study.With plants grown at room temperature(25 ℃) serving as the control,plants in a low-temperature environment(4 ℃) were treated with different concentrations of trehalose(0,5,10 and 20 mg/L).Relevant physiological indicators were measured,including maximum photochemical efficiency of photosystem Ⅱ(
Fv/
Fm),chlorophyll content,reactive oxygen species(ROS) and malondialdehyde(MDA) levels,antioxidant enzyme activity(SOD,POD,CAT and APX),and osmoregulatory substance content.The results showed that low-temperature stress significantly inhibited photosynthesis in strawberry leaves and increased the accumulation of ROS content.The application of trehalose at certain concentrations effectively alleviated the effects of low-temperature stress,with the 10 mg/L treatment yielding the best overall results.Following treatment at this concentration,the
Fv/
Fm value of strawberry leaves increased by 20.03% compared to the low-temperature control group,and total chlorophyll content increased by 56.12%;SOD,POD,CAT and APX enzyme activities increased by 30.59%,120.26%,154.58% and 62.50%,respectively;H
2O
2,·O
2-and MDA levels decreased significantly;soluble sugar,soluble protein and endogenous trehalose content increased by 56.09%,39.97% and 44.26%,respectively.Furthermore,correlation analysis indicated that the effect of trehalose treatment on strawberry tolerance to low-temperature stress was not significantly related to protein content.In summary,exogenous application of 10 mg/L trehalose can alleviate the adverse effects of low-temperature stress on strawberry leaves by enhancing photosynthetic efficiency,increasing antioxidant enzyme activity,and regulating the accumulation of osmotic substances.