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

Abstract

: This study was performed to investigate the effects of sowing density and number of seeds sown on the emergence rate 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 cultivated in sandy loam soil within a blue plastic greenhouse. In contrast to the emergence rate, which decreased with an increase of sowing density, number of survival plant showed an increasing trend. Interestingly, the emergence and number of survival plant were significantly enhanced when 2 or 3 seeds were sown per hole compared with when one seed was sown per 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 root length, diameter, and weight, and the number of lateral roots decreased with an increase in sowing density, but were not noticeably influenced by the number of seeds sown. Total saponin content was the highest in the treatment plot containing 135 seeds. Similarly, the content of each ginsenoside was also tended to be higher in this treatment than in other treatment plots. On the basis of the results obtained in this study, it was possible to determine the optimal sowing density and seed number for the direct sowing cultivation of ginseng in blue plastic greenhouse.

Importance of environmental factors on plantings of wild-simulated American Ginseng

“…Across the plots we measured, the seeding rate ranged from 21-70 seeds per square meter, or approximately 2-6.5 seeds per square foot (X= 38.056 seeds per square meter, sd = 10.529). In controlled studies, over-sowing of ginseng seed has been shown to decrease plant emergence and root size (Mo et al 2014), while the clustering of plants in wild populations-though it may simply reflect dispersal limitations (Cruse-Sanders and Hamrick 2004a, b)could also suggest that ginseng plants are responding positively to favorable microsite conditions (Wagner and McGraw 2013;Wulfsberg 2019). Given that our plots exhibited a relatively narrow range of shade conditions, it is unclear whether the increasing positive effect of seeding density on plant density with decreasing shade levels would continue under sunnier conditions.…”