Effect of Sowing Density and Number of Seeds Sown on Panax ginseng C. A. Meyer Seedling Stands under Direct Sowing Cultivation in Blue Plastic Greenhouse

This study was performed to investigate the effects of sowing density and number of seeds sown on the emergencerate and growth characters of Panax ginseng C. A. Meyer under direct sowing cultivation in a blue plastic greenhouse. Ginseng seedlings, derived from seeds sown directly at different densities (90, 108, 135, and 162 seeds per 1.62 ㎡), were cultivatedin sandy loam soil within a blue plastic greenhouse. In contrast to the emergence rate, which decreased with anincrease of sowing density, number of survival plant showed an increasing trend. Interestingly, the emergence and numberof survival plant were significantly enhanced when 2 or 3 seeds were sown per hole compared with when one seed was sownper hole. Growth of the aerial parts of ginseng were not markedly influenced by sowing density or the number of seeds sown. However, chlorophyll content (SPAD values) increased with an increase in sowing density. Root parameters, such as rootlength, diameter, and weight, and the number of lateral roots decreased with an increase in sowing density, but were notnoticeably influenced by the number of seeds sown. Total saponin content was the highest in the treatment plot containing135 seeds. Similarly, the content of each ginsenoside was also tended to be higher in this treatment than in other treatmentplots. On the basis of the results obtained in this study, it was possible to determine the optimal sowing density and seednumber for the direct sowing cultivation of ginseng in blue plastic greenhouse.