A survey on the graft healing environment of commercial fruit vegetable plug seedling greenhouses in the Republic of Korea

Abstract

Seedling production is the basis of most agricultural, especially horticultural, cultivation and is important for crop cultivation. The quality of seedlings directly affects the quality and yield of crops after transplanting. The scale of seedling production in the Republic of Korea has increased gradually and significantly, and the proportion of grafted seedlings of fruit vegetables has become increasingly important. The quality of grafted vegetable seedlings is valued by farmers more than before; thus, the quality of grafted seedlings of fruit vegetables has become an important area of study. To determine the direction of this research, we surveyed several representative seedling production growers in different provinces of the Republic of Korea. We investigated the graft healing methods used by Korean growers of fruit vegetable plug seedlings, including the light intensity, air temperature, and relative humidity in plug seedling cultivation greenhouses, graft healing tunnels, and closed-type graft healing factories in summer and winter seasons. It was found that the graft healing methods used by different growers varied. There were vast differences in air temperature and relative humidity between graft healing tunnels and closed-type healing factories. In greenhouses, the temperature in winter was low and the light intensity was insufficient, while the temperature in summer was high and relative humidity was too low to be optimal for grafted seedlings. Due to the differences in covering materials, the light spectrum in cultivation greenhouses and the graft healing spaces also varied among growers. In general, there were no standardized production models or environmental conditions for grafted plug seedling cultivation. Therefore, follow-up studies will be needed for the development of the grafted plug seedling industry in Republic of Korea.