| Summary: | Hydrogen gas (H<sub>2</sub>) is considered as a signaling molecule and plays multiple roles in plant growth. However, the effect of H<sub>2</sub> on postharvest physiology in lily scales during storage has not been reported. In this study, the regulatory roles of hydrogen-rich water (HRW, a H<sub>2</sub> donor, a concentration of 0.45 mM for 100% HRW) in water status, ion balance, and nutrients in Lanzhou lily (<i>Lilium davidii</i> var. <i>unicolor</i>) scales were investigated. The scales were soaked in HRW for 12 d, and sampling was performed every 3 d for a total of 5 times. The results show that HRW (0, 10, 50, and 100%) increased the fresh weight, dry weight, relative water content, and water loss rate in lily scales, with maximum biological response at 50% HRW. Treatment with 50% HRW significantly increased the K<sup>+</sup> content and K<sup>+</sup>/Na<sup>+</sup> ratio in lily scales and decreased Na<sup>+</sup> content. The Na<sup>+</sup> K<sup>+</sup>-ATPase, and PM H<sup>+</sup>-ATPase activities were also increased by 50% HRW treatment. Meanwhile, 50% HRW up-regulated the expression of <i>AKT1</i> and <i>HA3</i> genes and down-regulated the expression of <i>NHX2</i> and <i>SOS1</i> genes. In addition, 50% HRW treatment significantly increased the expression level of <i>PIP1;5</i>, <i>PIP2A</i>, <i>TIP1;3</i>, and <i>TIP2;2</i> genes. Treatment with 50% HRW significantly increased the content of water-soluble carbohydrate, sucrose, glucose, and fructose in lily scales, and decreased the content of starch. In addition, 50% HRW treatment significantly increased the activity of α-amylase, β-amylase, total amylase, sucrose synthase, and sucrose phosphate synthase. Collectively, H<sub>2</sub> might enhance the water retention capacity and nutrient content in lily scales by maintaining ion balance, regulating aquaporin, and increasing sugar-metabolizing enzyme activity, thereby prolonging the storage period of postharvest scales of Lanzhou lily.
|
|---|