Production of grafted vegetable seedlings in the republic of korea: Achievements, challenges and perspectives

Since the first commercial vegetable seedling production business was established in the Republic of Korea in 1992, technologies for the production of vegetable grafted seedlings have been developed. Commercial grafting nurseries have promoted the efficiency of grafted seedling production by the selection and concentration strategy. At present, most scions and rootstocks are concentrated on one or two cultivars and all grafted seedlings are made by the splice grafting method. To overcome the disadvantages of the splice grafting method, such as delayed formation of the grafted union and delayed rooting, light-emitting diode (LED) healing chambers (LHCs) have been developed for enhancing grafted union formation, and are currently used in 20% of commercial grafting nurseries. The commercial grafting nurseries in Korea have been facing highly difficult situations because of climate change, increased seedling production cost and labor shortage. To confront this challengeable circumstance, it is essential to optimize grafted seedling production practices to produce high-quality seedlings at lower cost and low impact on the environment, and to ensure a consistent supply to vegetable growers year round. Here, we explored several practices to improve productivity and reduce the environmental impact of grafted seedling production, including the development of disease resistant or abiotic stress tolerant rootstock cultivars, the development of more precise and efficient facilities and cultivation systems such as a grafting robot, the application of a plant factory with artificial lighting, the improvement of light condition in LHCs, and wastewater reuse.