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Sirtuins (SRTs) are a group of nicotinamide adenine dinucleotide (NAD+)‐dependent deacetylase that target both histone and nonhistone proteins. The biological function of SRT in horticultural plants has been rarely studied. In this study, FaSRT1‐2 was identified as a key member of the 8 FaSRTs encoded in cultivated strawberry genome. Transient overexpression of FaSRT1‐2 in strawberry fruit accelerated ripening, increased the content of anthocyanins and sugars, enhanced ripening‐related gene expression. Moreover, stable transformation of FaSRT1‐2 in strawberry plants resulted in enhanced vegetative growth, increased sensitivity to heat stress and increased susceptibility to Botrytis cinerea infection. Interestingly, knocking out the homologous gene in woodland strawberry had the opposite effects. Additionally, we found the content of stress‐related hormone abscisic acid (ABA) was decreased, while the growth‐related gibberellin (GA) concentration was increased in FaSRT1‐2 overexpression lines. Gene expression analysis revealed induction of heat shock proteins, transcription factors, stress‐related and antioxidant genes in the FaSRT1‐2‐overexpressed plants while knocked‐out of the gene had the opposite impact. In conclusion, our findings demonstrated that FaSRT1‐2 could positively promote strawberry plant vegetative growth and fruit ripening by affecting ABA and GA pathways. However, it negatively regulates the resistance to heat stress and B. cinerea infection by influencing the related gene expression. Summary statement: FaSRT1‐2 is likely to exert a positive regulatory effect on both strawberry fruit ripening and vegetative growth by stimulating sugar, anthocyanin, and the gibberellin metabolism pathway. Moreover, FaSRT1‐2 appears to enhance the susceptibility of strawberry plants to heat stress while also promoting defence against Botrytis cinerea through alterations in abscisic acid metabolism and stress‐related genes expression. [ABSTRACT FROM AUTHOR]

Strawberry is a worldwide demanded edible fruit with high economic and nutritional value; however, a very short storage life largely limits its supply and marketing. In this study, strawberries were treated using sodium selenite with different concentrations (6, 12, 18, and 24 mg/L), and the postharvest fruit quality and resistance to Botrytis cinerea were substantially assessed. Among all concentrations, 12 mg/L Se was the most effective treatment, which maintained fruit skin brightness, reduced natural decay incidence, severity, and weight loss, increased the Se content in fruit, and thus maintained the postharvest fruit quality of the strawberry. Furthermore, strawberries treated with 12 mg/L Se had lower flavonoid, phenolic, anthocyanins, proanthocyanidins, H2O2, and O2− contents compared to the control and, correspondingly, lower antioxidant capacity; moreover, 12 mg/L Se treatment decreased the decay incidence and severity caused by the infection of B. cinerea. Collectively, our findings may provide a reference for developing safe and environmentally friendly alternative methods to sustain quality and manage gray mold in postharvest strawberries as well as other horticultural crops. [ABSTRACT FROM AUTHOR]

• A stable genetic strawberry mutant with high epicuticular wax was identified, which content was 1.74 times higher than that of 'Benihoppe'. • The primary alcohols (C18, C20, C22, C24, C25 and C26), alkanes (C20 and C31) and fatty acids (C26) were the main components of cuticular wax in the mutant, which significantly increased by 138.37%, 53.69% and 86.80%, respectively, compared with that of 'Benihoppe'. • A comparative transcriptomic analysis identified FaKAS2, FaFATA2, FaLACS1, FaKCS12/19, FaPAS2, FaECR, FaCER1 and FAR3/5 as potential key genes involved in wax synthesis of strawberry leaves. • Cuticular wax in MT may be the main contributor to the observed enhancements in the resistance to Tetranychus urticae Koch and Botrytis cinerea. Cuticular wax is crucial for plant defense against biotic and abiotic stresses, but its relationship with resistance in strawberries is not well understood. A stable genetic mutant (MT) of 'Benihoppe' strawberries with a glossier leaf surface and stronger resistance was identified during cultivation. In this study, we analyzed the anatomical and physiological traits of leaves from 'Benihoppe' and its mutant and compared their cuticular wax properties. We also analyzed the differentially expressed genes involved in leaf cuticular wax accumulation and investigated their characteristics against Tetranychus urticae Koch and Botrytis cinerea. Comparisons between morphological and physiological features revealed that the mutant had smaller, darker leaves with a thicker upper epidermis and palisade tissue. GC-MS analysis showed that the total cuticular wax content of the MT leaf (1147.84 μg/dm2) had 1.74 times more total wax content than that of 'Benihoppe' (660.66 μg/dm2). The main components of cuticular wax in the MT leaf were primary alcohols (C18, C20, C22, C24, C25 and C26), alkanes (C20 and C31) and fatty acids (C26), whose content increased by 138.37%, 53.69% and 86.80%, respectively, compared with that of 'Benihoppe'. Based on the comparative transcriptome data, we identified FaKAS2, FaFATA2, FaLACS1, FaKCS12 / 19, FaPAS2, FaECR, FaCER1 and FAR3/5 as potential key genes involved in wax synthesis of strawberries. Furthermore, MT leaves exhibited lower susceptibility to Tetranychus urticae Koch and its cuticular wax extraction inhibited the growth of Botrytis cinerea more effectively. Therefore, the increase of total cuticular wax and the content of major wax components in MT may be the main contributor to the enhanced resistance. These results not only deepen our understanding of the cuticular wax regulation but also provide potential gene resources for developing more resistant strawberry varieties. [ABSTRACT FROM AUTHOR]