Evaluation of Ginseng (Panax quinquefolius) Germination and Aeroponic Seedling Growth in Response to Stratification Duration, GA3, De-coating, and Media

Ginseng (Panax quinquefolius) is a well-known and commonly used Chinese herb for improved brain functions, pain relieving effects, enhanced immune system and liver function, as well as anti-stress and anti-fatigue effects. In its natural habitat, ginseng grows in heavily shaded forest type locations. However, a great deal of failure has occurred in the process of trying to grow this plant in a production setting. Ginseng can naturally take anywhere between six to twelve years for it to fully mature. Our objective was to evaluate methods to enhance germination rates and uniformity while producing seedlings for aeroponic production. Three hundred warm stratified Ginseng seeds were cold moist stratified for six weeks. Half of the seeds were then soaked in a 0.1% gibberellic acid (GA₃) solution prior to stratification (Pre-strat), while the other half received the same GA₃ soak at the end of the stratification (Post-strat). After 6 weeks, 64% of the Pre-strat seeds, and 76% of the Post-strat seeds exhibited endocarp splitting (smiling). 150 smiling seeds of each group were randomly selected and the non-smiling seeds were returned to the stratification environment for an additional 8 weeks. Half of each group (6 week strat) were then de-coated, resulting in 75 seeds of each treatment; Pre-strat with coat, Pre-strat de-coated, Post-strat with coat, and Post-strat de-coated. All 300 seeds were then planted in coarse sand and placed onto an automated mist bench. Seedling emergence was observed over an eight week period. The seeds which were stratified for an additional 8 weeks were observed for germination after the full 14 week stratification. Eighteen seedlings at the one true leaf stage were randomly assigned to three media treatments and placed in an automated aeroponic system where growth was evaluated over 12 weeks. Seeds treated with GA₃ prior to stratification emerged at significantly higher rates than seeds treated after the 6 week stratification. De-coating yielded no significant difference in germination percentage. Overall, germination was lower in all 6 week stratification treatments compared to seeds stratified for 14 weeks. Eighteen seedlings were selected and assigned to each of three media treatments used in the aeroponic unit. The treatments were 1) peat moss, 2) perlite, and a 3) 1:1 mix of peat moss and perlite. Growth, chlorophyll content, and mortality were observed over 3 months. Seedling growth parameters differed in response to media with the fine peat moss performing significantly worse than the others.