Growth of Grafted Cucumber Seedlings as Affected by Different EC Levels and Cultivars

The nutrient solution used for plant growth contains water and essential inorganic nutrients.The concentration of these nutrients can be measured through electrical conductivity.It is essential to find the proper nutrient solution concentration because different crops exhibit different growth responses depending on the level of the electrical conductivity (EC).Therefore, this experiment was conducted to determine the proper EC level for grafted cucumber seedling production, considering different cultivars.Three cultivars of cucumber (Cucumis sativus L.) were used as scions for grafting: 'NakWonSeongcheongjang (NWS)', 'Sinsedae (SD)', and 'Goodmorning baekdadagi (GB)'.Figleaf gourd (Cucurbita ficifolia) 'Heukjong' was used as the rootstock.They were grafted on September 18, 2023.After graft-taking, cucumber seedlings in plug trays were moved to a closed-type plant production system.Cucumber seedlings in plug trays were treated with the EC 1.5, 2.0, and 2.5 dSm -1 .EC of tap water was used as the control.Fresh and dry weights of shoots were significantly increased in all cultivars at the EC 2.0 and 2.5 dSm -1 in all cultivars.In particular, leaf length, leaf width, and leaf area of NWS and GB were significantly increased in EC 2.0 and 2.5 dSm -1 .Seedling qualities such as compactness and leaf area rate were also increased in EC 2.0 and 2.5 dSm -1 .As the EC levels increased, specific leaf area increased.SPAD, chlorophyll a and b were significantly higher in EC 2.0 and 2.5 dSm -1 .Except for the control, the other treatments had leaf area index values above 4.In conclusion, EC 2.0 dSm -1 in grafted cucumber seedlings can improve growth, seedling quality, and chlorophyll concentrations.