Hassan Sarikhani; Mohammad-Sadegh Safariyan-Nejad
Abstract
One of the most important problems of strawberry cultivation in temperate regions is winter cold injuries. Current study investigated impacts of foliar application of glycine betaine (GB) at 0, 0.5, 1, 2 and 4 mM concentrations on the cold hardiness of strawberry. The plants were divided into two groups: ...
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One of the most important problems of strawberry cultivation in temperate regions is winter cold injuries. Current study investigated impacts of foliar application of glycine betaine (GB) at 0, 0.5, 1, 2 and 4 mM concentrations on the cold hardiness of strawberry. The plants were divided into two groups: one group for evaluation of cold hardiness at temperatures of -6, -9, -12, -15 and -18 °C; and the other for study of some biochemical characteristics. Results showed that GB treatment increased soluble carbohydrate and proline concentrations in both leaf and crown tissues, total protein concentration in leaf, and relative water content in leaf as compared to those in control. Based on LT50 calculated from electrolyte leakage and tetrazolium staining test, the GB application increased cold hardiness in strawberry plant based on its concentration. The highest cold hardiness was found in the 2 mM GB concentration based on electrolyte leakage and tetrazolium staining tests at -13.3 and -15.3 °C. Meanwhile, the lowest values of cold hardiness were observed in the control treatments based on electrolyte leakage and tetrazolium staining tests at -10.2 and -11.0 °C. Significant correlations were found between soluble carbohydrate and proline concentrations in leaf and crown, and total protein concentration with LT50 calculated from electrolyte leakage and tetrazolium staining test. We conclude that application of 2 mM GBhas the capacity to increase the freezing tolerance of strawberry and could be used as a prophylactic tool to reduce winter cold injury.
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.