Morphological and Ginsenoside Differences among North American Ginseng Leaves

Proctor, John T.A.,Sullivan, Alan J.,Rupasinghe, Vasantha P.V.,Jackson, Chung-Ja C. The Korean Society of Ginseng 2011 Journal of Ginseng Research Vol.35 No.2

Leaf characteristics of mature 2, 3 and 4-year-old North American ginseng (Panax quinquefolius L.) leaves on fruiting and non-fruiting(NF) plants were studied. Leaflets of the 2-year-old plants had the lowest fresh and dry weight, area, volume and internal gas volume. Inflorescence removal in 3-year-old plants did not affect leaf characteristics or ginsenoside concentration but in 4-year-old plants it increased leaf fresh (38.6%) and dry (43.9%) weight, leaf area (29.1%), specific leaf mass (11.4%), leaf volume (43.1%), and leaf thickness (12.1%), and decreased leaf water content (6.2%). Cultivated ginseng, although an understorey plant, had the specific leaf mass, 35.6 g $m^{-2}$ (range, 36 to 39 g $m^{-2}$) and a chlorophyll a/b ratio of 2.40 to 2.61, both suggesting the ability to perform like a sunny habitat plant. Also, specific leaf mass of 35.6 g $m^{-2}$ is similar to that reported for perennial plants, 36.8 g $m^{-2}$, rather than that for annuals, 30.9 g $m^{-2}$.

Morphological and Ginsenoside Differences among North American Ginseng Leaves

John T. A. Proctor,Alan J. Sullivan,Vasantha P. V. Rupasinghe,Chung-Ja C. Jackson 고려인삼학회 2011 Journal of Ginseng Research Vol.35 No.2

Leaf characteristics of mature 2, 3 and 4-year-old North American ginseng (Panax quinquefolius L.) leaves on fruiting and nonfruiting (NF) plants were studied. Leaflets of the 2-year-old plants had the lowest fresh and dry weight, area, volume and internal gas volume. Inflorescence removal in 3-year-old plants did not affect leaf characteristics or ginsenoside concentration but in 4-yearold plants it increased leaf fresh (38.6%) and dry (43.9%) weight, leaf area (29.1%), specific leaf mass (11.4%), leaf volume (43.1%), and leaf thickness (12.1%), and decreased leaf water content (6.2%). Cultivated ginseng, although an understorey plant, had the specific leaf mass, 35.6 g m?² (range, 36 to 39 g m?²) and a chlorophyll a/b ratio of 2.40 to 2.61, both suggesting the ability to perform like a sunny habitat plant. Also, specific leaf mass of 35.6 g m?² is similar to that reported for perennial plants, 36.8 g m?², rather than that for annuals, 30.9 g m?².

Acclimation of maximum quantum yield of PSII and photosynthetic pigments of Panax quinquefolius L. to understory light

Anick R. Fournier,John T.A. Proctor,Shahrokh Khanizadeh,André Gosselin,Martine Dorais 고려인삼학회 2008 Journal of Ginseng Research Vol.32 No.4

Forest-grown American ginseng (Panax quinquefolius L.) is exposed to daily and seasonal light variations. Our goal was to determine the effect of understory light changes on the maximum quantum yield of photosystem II, expressed as Fv/Fm, and photosynthetic pigment composition of two-year-old plants. Understory light photon flux density and sunfleck durations were characterized using hemispherical canopy photography. Our results showed that understory light significantly affected the Fv/Fm of American ginseng, especially during the initial development of the plants when light levels were the highest, averaging 28 mol m-2 d -1. Associated with low Fv / Fm during its initial development, American ginseng had the lowest levels of epoxidation state of the xanthophyll cycle of the season, suggesting an active dissipation of excess light energy absorbed by the chlorophyll pigments. As photon flux density decreased after the deployment of the forest canopy to less than 10 mol m-2 d -1, chlorophyll a/b decreased suggesting a greater investment in light harvesting pigments to reaction centers in order to absorb the fleeting light energy.

Acclimation of maximum quantum yield of PSⅡ and photosynthetic pigments of Panax quinquefoulius L. to understory light

Anick R. Fournier,John T.A. Proctor,Shahrokh Khanizadeh,Andre Gosselin,Martine Dorais 고려인삼학회 2008 Journal of Ginseng Research Vol.32 No.4

Forest-grown American ginseng (Panax quinquefolius L.) is exposed to daily and seasonal light variations. Our goal was to determine the effect of understory light changes on the maximum quantum yield of photosystem Ⅱ, expressed as Fv/Fm, and photosynthetic pigment composition of two-year-old plants. Understory light photon flux density and sunfleck durations were characterized using hemispherical canopy photography. Our results showed that understory light significantly affected the Fv/Fm of American ginseng, especially during the initial development of the plants when light levels were the highest, averaging 28 mol m<SUP>-2</SUP>d<SUP>-1</SUP>. Associated with low Fv/Fm during its initial development, American ginseng had the lowest levels of epoxidation state of the xanthophyll cycle of the season, suggesting an active dissipation of excess light energy absorbed by the chlorophyll pigments. As photon flux density decreased after the deployment of the forest canopy to less than 10 mol m<SUP>-2</SUP>d<SUP>-1</SUP>, chlorophyll a/b decreased suggesting a greater investment in light harvesting pigments to reaction centers in order to absorb the fleeting light energy.

Source-Sink Relations in North American Ginseng Seedlings as Influenced by Leaflet Removal

John T. A. Proctor 고려인삼학회 2008 Journal of Ginseng Research Vol.32 No.4

Seedlings of North American ginseng (Panax quinquefolius L.) were grown to full canopy establishment and then leaflet or leaf removal at different times applied to determine the effects on plant growth and performance. Leaf removal at 47, 57, 69 and 78 days after seeding resulted in 82.1, 59.8, 41.3 and 29.8% reduction, respectively, in root dry matter (economic yield) ; this indicates that leaf removal during the early root growth period causes greatest reduction in root yield. Removal of 1, 2, and 3 leaflets at 42, 52, 62 and 70 days from seeding reduced root weight at harvest (80 days from seeding) linearly, particularly at earlier removal dates. The perennating bud formed on all roots and was not influenced by treatment. This would suggest that if leaf loss occurs after canopy establishment the plant will re-grow the next year after the obligatory dormancy period.

미국삼 종자의 매장처리 : 배 성장과 온도 ( Stratification of American Ginseng Seed : Embryo Growth and Temperature )

John T. A. Proctor,Dean Louttit 고려인삼학회 1995 Journal of Ginseng Research Vol.19 No.2

Growth, Dry Matter Partitioning and Photosynthesis in North American Ginseng Seedlings

John T. A. Proctor,John W. Palmer,John M. Follett 고려인삼학회 2010 Journal of Ginseng Research Vol.34 No.3

North American ginseng seedlings (Panax quinquefolius L.) were grown in pots in heated greenhouses, in a cool greenhouse, or in the field, in 11 experiments at various times over 16 years. Crop establishment, dry matter partitioning, photosynthesis, radiation use efficiency and carbon budget were measured and/or calculated in some years. Once the seedling canopy, of about 20 ㎠ per seedling, and a leaf area index of 0.37, was established, about 40 days after germination, full canopy display lasted about 87 days. Only 16.6% of the incoming solar radiation was intercepted by the crop, the remainder falling on the mulched soil surface. Total and root dry matter accumulations in the cool greenhouse and in the field were about double that in the heated greenhouses. Partitioning of dry matter to roots (economic yield or harvest index) in the cool greenhouse and in the field was 73% whereas it was 62.5% in the heated greenhouses. The relationship between root dry matter and radiation interception during the full canopy period was linear with growth efficiencies of 2.92 ㎎ MJ?¹ at 4.8% of incoming radiation and 0.30 ㎎ MJ?¹ at 68% of incoming radiation. A photosynthetic rate of 0.39 g m?² h?¹ was attained at light saturation of about 150 μ㏖ m?² s?¹ (7.5% of full sunlight); dark respiration was 0.03 g m?² h?¹, about 8.5% of maximum assimilation rate. Estimates of dry matter accumulation by growth analysis and by CO₂ uptake were similar, 6.21 vs. 7.62 ㎎ CO₂, despite several assumptions in CO₂ uptake calculations.

Effect of boron nutrition on American ginseng in field and in nutrient cultures

John T.A. Proctor,Barry J. Shelp 고려인삼학회 2014 Journal of Ginseng Research Vol.38 No.1

Field and nutrient cultures of American ginseng (Panax quinquefolius L.) were used to establish foliar symptoms related to boron (B) concentration in leaves and soils, and to evaluate radish as a time-saving model system for B nutrition. Application of excess B, 8 kg/ha versus the recommended 1.5 kg/ha, to field plantings of 2-, 3-, and 4-yr-old American ginseng plants just prior to crop emergence caused, within 4 wk after crop emergence, leaf symptoms of chlorosis followed by necrosis starting at the tips and progressing along the margins. The B concentration in leaves of 2-4-yr-old plants receiving 1.5 kg/ha Bwas 30 μg/g dry mass compared to 460 μg/g dry mass where 8 kg/ha B was applied. Similarly, B concentration in soils receiving the lower B concentration was 1.8 μg/g dry mass and 2.2-2.8 μg/g dry mass where the higher B concentration was applied. Application of 8 kg/ha B reduced the dry yield of 3rd-yr roots by 20% from 2745 kg/ha to 2196 kg/ha and 4th-yr roots by 26% from 4130 kg/ha to 3071 kg/ha. Ginseng seedlings and radish were grown under greenhouse conditions in nutrient culture with four B concentrations ranging from 0 mg/L to 10 mg/L. At 5 mg/L and 10 mg/L ginseng and radish developed typical leaf B toxicity symptoms similar to those described above for field-grown plants. Increasing B in the nutrient solution from 0.5 mg/L to 10 mg/L decreased, in a linear fashion, the root and leaf dry mass of ginseng, but not radish. Given the many similarities of ginseng and radish to B utilization, radish might be used as a timesaving model system for the study of B, and other micronutrients, in the slow-growing perennial ginseng.

Low-Temperature Storage of Immature (Green) North American Ginseng Seed for Fall Planting

Proctor John T.A.,Louttit Dean The Korean Society of Ginseng 2006 Journal of Ginseng Research Vol.30 No.2

Freshly harvested, immature (green) seeds of North American ginseng (Panax quinquefolius L.) were stratified for up to 3 years in plastic pails in controlled environment rooms at $5{\pm}1^{\circ}C$ for 9 months and then $21{\pm}2^{\circ}C$ for 3 months (Trt. 1, regular stratification), or continuously at $-2{\pm}0.2^{\circ}C$ (Trt. 2), or continuously at $3{\pm}0.2^{\circ}C$ (Trt. 3). During stratification at -2 and $3^{\circ}C$ embryos did not grow. On seeding in the field embryos grew rapidly and resultant seedlings were comparable to those from regularly stratified seed. Seedling emergence rate was acceptable at the industry expected rate of 68% after one year of storage, but not after two years storage when it declined to 17.5%. Seed rot was so severe in year 3 that no planting was carried out. Seedling and second year growth were similar at the three stratification temperatures; most importantly, root dry weight (economic yield) was similar. Low-temperature storage of freshly-harvested North American ginseng seed is an acceptable method for short-term retention of propagating material.

Low-Temperature Storage of Immature (Green) North American Ginseng Seed for Fall Planting

John T.A. Proctor,Dean Louttit 고려인삼학회 2006 Journal of Ginseng Research Vol.30 No.2

Freshly harvested, immature (green) seeds of North American ginseng (Panax quinquefolius L.) were stratified for up to 3 years in plastic pails in controlled environment rooms at 5±1℃ for 9 months and then 21± 2℃ for 3 months (Trt. 1, regular stratification), or continuously at -2±0.2℃ (Trt. 2), or continuously at 3±0.2℃ (Trt.3). During stratification at -2 and 3℃ embryos did not grow. On seeding in the field embryos grew rapidly and resultant seedlings were comparable to those from regularly stratified seed. Seedling emergence rate was acceptable at the industry expected rate of 68% after one year of storage, but not after two years storage when it declined to 17.5%. Seed rot was so severe in year 3 that no planting was carried out. Seedling and second year growth were similar at the three stratification temperatures; most importantly, root dry weight (economic yield) was similar. Low-temperature storage of freshly-harvested North American ginseng seed is an acceptable method for short-term retention of propagating material.