Application Of Hydrogen-Rich Water In Soil Cultivation And Substrate Cultivation Of Strawberry Greenhouse

Strawberry（Fragaria×ananassa Duch.）is one of people’s favorite fruits with excellent taste and nutritional value in daily life.Long-term agricultural practices indicate that the cultivation of strawberries requires a lot of chemical fertilizers and pesticides,which not only causes serious damage to the agricultural ecological environment,but also leads to certain hidden dangers in food safety.Ample researches show that hydrogen（H₂）as a kind of gas signal molecule has the characteristics of environmentally friendly,green and low-carbon.H₂can not only promote the growth and development of plants and increase the tolerance of plants to abiotic stress,but also have a certain effect on the improvement of crop yield and nutritional quality.In field practice,H₂generally acts on plants in the form of electrolysis of hydrogen-rich water（HRW）.However,the electrolysis of HRW has some disadvantages,such as fast dissipation and short half-life.Therefore,HRW has the defect of short acting time during large-scale planting,which limits the biological effect of H₂.The nanobubble refers to a new type of technology with a bubble diameter of less than 1000 nm..Nanobubble hydrogen-rich water（Nano-HRW）formed by the combination of nanobubble technology and H₂has the characteristics of high concentration and long residence time,which is more suitable for field application,in comparison with the electrolysis HRW.However,the above-mentioned research only stays at the laboratory stage,and there are few reports on its application in field.Regarding the above problems,we chooses two strawberry greenhouses in Qingpu,Shanghai（soil cultivated strawberries）and Jiande,Zhejiang（substrate cultivated strawberries）to explore the application of HRW based on H₂.Firstly,HRW and Nano-HRW were irrigated to explore the effects of both on the yield and quality of strawberries in the strawberry greenhouse of Qingpu,Shanghai.It was found that irrigation with HRW and Nano-HRW improved the yield and quality of strawberries compared with surface water（SW）,and Nano-HRW has more obvious effect on the increase yield of strawberry.Then,we further explored the effect of different concentrations of Nano-HRW on the yield and quality of strawberries,and found that different concentrations of Nano-HRW also improved the quality and yield of strawberries.The main results are as follows:Irrigation with HRW and Nano-HRW both can increase the accumulation of soluble sugar in strawberry（In the condition of free/normal fertilizers,compared to irrigation SW,irrigation with HRW.increased by 16.65%/16.44%,irrigation with Nano-HRW,increased by 25.61%/28.18%）by increasing the content of glucose,fructose and sucrose,thereby increasing sugar-acid ratio and sweetness of strawberry.HRW and Nano-HRW can also increase the average yield per plant of strawberry（In the condition of free/normal fertilizers,compared to irrigation SW,irrigation with HRW.increased by 15.7%/20.0%,irrigation with Nano-HRW,increased by 70.4%/59.5%）and content of soluble protein,ascorbic acid（In the condition of free/normal fertilizers,compared to irrigation SW,irrigation with HRW.increased by 6.79%/14.06%,irrigation with Nano-HRW,increased by 4.21%/9.70%）,total phenols and flavonoids in strawberries.The increasing of Nano-HRW on the yield is more obvious while the improvement of HRW is more pronounced on quality of strawberry.Importantly,the effect on increasing the yield of strawberry is more obvious under the conditions of free fertilizers with poor nutrition.Based on the above results,we further irrigated the substrate cultivated strawberries with low/high concentrations of Nano-HRW（Low concentration of Nanobubble hydrogen-rich water,L Nano-HRW,500-700 ppb;High concentration of Nanobubble hydrogen-rich water,H Nano-HRW,900-1200 ppb）.Consistent with the above results,both L/H Nano-HRW can increase the accumulation of soluble sugar in strawberries（In the condition of free/normal fertilizers,compared to irrigation SW,irrigation with L Nano-HRW.increased by 8.00%/6.99%,irrigation with H Nano-HRW,increased by20.59%/21.10%）by increasing the content of glucose,fructose and sucrose,and then increase the sugar-acid ratio,thereby improving the sweetness of strawberry.The L/H Nano-HRW can also increase the average yield per plant of strawberry（In the condition of free/normal fertilizers,compared to irrigation SW,irrigation with L Nano-HRW.increased by 8.84%/7.06%,irrigation with H-Nano-HRW,increased by 15.42%/8.91%）and content of soluble protein,ascorbic acid（In the condition of free/normal fertilizers,compared to irrigation SW,irrigation with L Nano-HRW.increased by 13.34%/3.60%,irrigation with H-Nano-HRW,increased by 16.59%/4.83%）,total phenols and flavonoids in strawberries,and the improvement of H Nano-HRW on the yield and quality is more obvious.In addition,irrigating L/H Nano-HRW can decrease the bad fruit rate of substrate strawberry（under the condition of normal fertilizers,decreased by 43.3%/43.3%）,and extend the shelf life of strawberry.Importantly,the above two concentrations of Nano-HRW can increase the yield of strawberry more obviously under the condition of free of fertilizers with poor nutrition.In conclusion,the field experiment with various areas and cultivation forms（soil and substrate）showed that irrigation with HRW and Nano-HRW can improve the quality and the yield of strawberry.The effect of HRW on improving strawberry quality is more pronounced,while Nano-HRW is more obvious on increasing the yield of strawberry.For different concentrations of Nano-HRW,irrigation L/H Nano-HRW also has a positive effect on the quality and yield of strawberry,and the effect of H Nano-HRW is more obvious.In addition,irrigation with Nano-HRW also exhibited the potential to decrease the rate of bad fruits and extend the shelf life of strawberry under the condition of substrate cultivation.,in comparison with irrigated SW.