• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.195-199
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• 1995

This study was conducted to investigate the Net photosynthesis and respiration rates among the varieties of Soybean(Eunha, Pangsa and Paldal that have high yields) at various leaf temperature and light intensity at the stage of $V_5$. The relations between the Net photosynthesis rate and SLW(specific leaf weight) and chlorophyll content were also investigated. 1. Net photosynthesis rates at $25^{\circ}C$ were $21.5mgdm^{-2}h^{-1}$ in cv. Eunha, $20.2mgdm^{-2}h^{-1}$ in cv. Pangsa and $18.5mgdm^{-2}h^{-1}$ in cv. Paldal. 2. Most cultivars of Soybean showed the maximum rates of Net photosynthesis at $25^{\circ}C$, especially in cv. Eunha. Also Net photosynthesis rates differed depending on the leaf shape. Long leaf shape(cv. Eunha) was better than round leaf shape(cv. Paldal) in Net photosynthesis rate. 3. Respiration rates of leaves in Eunha, Pangse and Paldal were $0.56mgdm^{-2}h^{-1}$ at $15^{\circ}C$, $0.79mgdm^{-2}h^{-1}$ at $20^{\circ}C$ $1.15mgdm^{-2}h^{-1}$ at $25^{\circ}C$ and $1.37mgdm^{-2}h^{-1}$ at $30^{\circ}C$. 4. Specific leaf weight were $3.1mg/cm^2$ in Pangsa, $3.5mg/cm^2$ in Eunha and Paldal. No signlficant difference were showed in net photosynthesis rates and specific lear weight. 5. Leaf chlorophyll content were $2.48{\mu}g/gF.W.$ in Eunha, $2.19{\mu}g/gF.W.$ in Pangsa and $1.67{\mu}/g F.W.$ in Paldal. Significant difference were showed in Net photosynthesis rates and Leaf chlorophyll content. 6. The estimated compensation points at which net photosynthesis approached zero were $10{\mu}Em^{-2}s^{-1}$ in Eunha, Pangsa, and Palda at 1$5^{\circ}C$. The compensation point in cv. Eunha at $20^{\circ}C$ was $12P{\mu}Em^{-2}s{-1}$ while $13{\mu}Em^{-2}s{-1}$ in Pangsa and Palda. The compensation point in cv. Paldal at $25^{\circ}C$ was $18{\mu}Em^{-2}s{-1}$ while $16{\mu}Em^{-2}s{-1}$ in Eunha and Pangsa. The compensation point in cv. Palda at $30^{\circ}C$ was $23{\mu}Em^{-2}s{-1}$ Palda while $13{\mu}Em^{-2}s{-1}$ in Eunha and Pangsa.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.292-298
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• 1997

To compare the growth pattern of ginseng plant under between conventional shading(light transmittance rate 3％) and polyethylene net shading(light transmittance rate 10％), the distribution of leaf area, specific leaf weight (S. L. W), leaf and stem dry weight and changes in light intensity were investigated in 2, 4 and 6 year old ginseng plant populations. Light transmittance rate(L.T.R.) was 3％ at front line, 2％ at middle line and 1.5％ at rear line under conventional shading but it was 12, 10 and 8％ under polyethylene net(P.E) shading, respectively. In 2 year old population, there was a little difference in the growth characteristics investigated between conventional and P.E. shading. In 4 year old field, the leaf area, stem and leaf dry weight decreased in large amount in the order of middle, and rear line on ridge under conventional shading, but with a little difference under P.E. shading. And these trends enlarged in 6 year old field with appearance of a large part of shoot over furrow from ridge planted ginseng. Root yield index was much lowered at the rear 3rd, 4th and 5th line of the conventional shading bed, but there was no yield difference among lines except 5th lines under the P.E. shading with higher yield by 28％ than conventional shading.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.412-418
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• 1985

Two fertilizer levels were treated to the nine barley varieties developed at different years to investigate the morphological and physiological traits related to grain yields. Recently developed varieties were higher in amounts of chlorophyll and nitrogen content of leaf, root activity, root weight and specipic leaf weight as compared with older varieties. Dry matter production was closely related to NAR rather than LAI in new varieties, but indicating the reverse results in older varieties. They showed higher NAR and light transmission rate in new varieties but higher LAI in older varieties. Leaves in new varieties were distributed uniformly according to its position on clum. However, leaves in older varieties arranged irregularly showing more distribution at the upper and middle positions on culm. The factors which showed high correlations with grain yield were chlorophyll content, root activity, NAR, and nitrogen content of leaf of which stepwise multiple regression with grain yield indicated that 90% of total variance was occupied by chlorophyll content, root activity and dry matter.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.94-98
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• 1982

To understand the growth pattern of ginseng plant under shading, the vertical distribution of leaf area, leaf area index (LAI) and specific leaf weight (SLW) and changes in light intensity as affected by planting position were investigated in 3 to 5 years old ginseng plant populations. Light intensity was vertically lowest at about 10cm above the ground and became low at the rear planting position in 3-year-old population. When culturing bed (96cm in width) were divided into three parts at intervals of 32cm from front to rear, the leaf area in 3-year-old population was largest in middle 1/3 part of planting bed. Light intensity affected the SLW positively, but LAI showed no distinct difference among planting positions. The light environment of 4-year-old population was worse than that of 3-year-old population and leaf area and LAI differed greatly among planting positions. In 5-year-old population, leaf dry weight and leaf area of furrow part (that is, the amount of leaves protruded from the plants which were planted in 1st, 2nd or 3rd lines into the furrow) increased. The dry weights of leaves and stem increased considerably as plant became aged, and were distributed mainly in upper layer.

• Journal of Bio-Environment Control
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• v.32 no.2
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• pp.148-156
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• 2023

This study was conducted in an indoor cultivation room and chamber where environmental control is possible to investigate the effect of temperature and irrigation interval on photosynthesis, growth and growth analysis of potted seedling cucumber. The light intensity (70 W·m^-2) and humidity (65%) were set to be the same. The experimental treatments were six combinations of three different temperatures, 15/10℃, 25/20℃, and 35/25℃, and two irrigation intervals, 100 mL per day (S) and 200 mL every 2 days (L). The treatments were named 15S, 15L, 25S, 25L, 35S, and 35L. Seedlings at 0.5 cm in height were planted in pots (volume:1 L) filled with sandy loam and treated for 21 days. Photosynthesis, transpiration rate and stomatal conductance at 14 days after treatment were highest in 25S. These were higher in S treatments with a shorter irrigation interval than L treatments. Total amount of irrigation water was supplied evenly at 2 L, but the soil moisture content was highest at 15S and lowest at 25S > 15L > 25L, 35S and 35L in that order. Humidity showed a similar trend at 15/10℃ (61.1%) and 25/20℃ (67.2%), but it was as high at 35/25℃ (80.5%). Cucumber growth (plant height, leaf length, leaf width, chlorophyll content, leaf area, fresh weight and dry weight) on day 21 was the highest in 25S. Growth parameters were higher in S with shorter irrigation intervals. Yellow symptom of leaf was occurred in 89.9% at 35S and 35L, where the temperature was high. Relative growth rate (RGR) and specific leaf weight (SLA) were high at 25/20℃ (25S, 25L), RGR tended to be high in the S treatment, and SLA in the L treatment. Water use efficiency (WUE) was high in the order of 25S, 25L > 15S > 15L, 35S, and 35L. As a result of the above, the growth and WUE were high at the temperature of 25/20℃.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.820-828
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• 2015

This study was carried out to determine the effects of vernalization, temperature, and soil water deficit (SD) on mesophyll cells, growth, and yield of Chinese cabbage (Brassica campestris L). The palisade parenchyma and spongy tissues of Chinese cabbage were observed under full irrigation and two weeks of SD treatment. These cells were severely collapsed by four weeks SD treatment. The SD treatment had the greatest influence on the growth of Chinese cabbage among the tested treatment factors (vernalization, temperature, and SD), growth significantly decreased by severe drought treatment (four weeks SD treatment). In addition, the relative growth rate, unit leaf rate, leaf area ratio, specific leaf area, and leaf weight ratio were significantly affected by SD treatment; however, other individual factors and their combined treatments did not influence the analyzed growth parameters. The yield under vernalization after high temperature and full irrigation treatments was 3,056 kg/10 a, which was the greatest among all the tested treatments, while four-week SD treatment significantly reduced the yield. Head formation of Chinese cabbage was not altered under SD treatment, and vernalization treatments did not induce bolting. Our results indicated that collapsing mesophyll cells and reduced growth and yield were induced by SD treatment. Thus we suggest that optimal irrigation system should be install to avoid or overcome crippling drought conditions in the open field.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.762-770
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• 2014

This study was conducted to elucidate the influence of prohexadione-calcium (Pro-Ca) application on shoot growth and fruit quality in 'Fuji'/M.9 mature apple trees. Pro-Ca was applied at concentrations ranging from 100 to $400mg{\cdot}L^{-1}$ one time at petal fall (PF; 5-10 cm terminal shoot growth) to the whole canopy of the tree, or at 100, 125, $150mg{\cdot}L^{-1}$ concentrations two times, at PF and then 4-8 weeks after PF. Pro-Ca treatment generally reduced mean shoot growth, with its effect being proportional to the application rate. Pro-Ca at $400mg{\cdot}L^{-1}$ significantly reduced the shoot growth by 15-22% compared to the control, while its effect was not significantly different from Pro-Ca $200mg{\cdot}L^{-1}$. Pro-Ca treatments induced higher occurrence of secondary growth compared to the control. Pro-Ca treatment increased the photosynthetic rate by 5-10% relative to the control, and also increased soluble solid concentration and fruit red color. However, fruit weight was significantly reduced by $400mg{\cdot}L^{-1}$ Pro-Ca, which was attributable to the greater secondary growth caused Pro-Ca $400mg{\cdot}L^{-1}$ treatment compared to the control and Pro-Ca $200mg{\cdot}L^{-1}$ treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.157-162
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• 1987

The study was carried out to investigate the effects of light intensity, temperature and seasonal trends on the photosynthesis as well as the physiological characteristics of Panax species and cultivars. Four-year-old plant of Violet-stem variant, Yellow-berry variant, Mimaki and Russian ginseng of Panax ginseng C. A. Meyer and American ginseng of Panax quiquefolium L. were used for study. These Panax species and cultivars were cultivated under the straw shading. The light saturation point of leaves in Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 15,000 lux, but that of Russian ginseng was 10,000 lux. The optimum air temperature on the phtosynthesis of Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 20$^{\circ}C$ but that of Russian ginseng was 15$^{\circ}C$ under 15,000 lux. The photosynthetic rates were increased in order of Russian ginseng, Mimaki, Yellow-berry variant, Violet-stem variant and American ginseng. The respiration rates of ginseng leaves were increased according to the increasing of temperature, but it was not different among Panax species and cultivars. Stomata frequency of American ginseng was highest, that of Russian ginseng lowest, while the length of stomata was reverse. The total chlorophyll content of American ginseng and specific leaf weight of Mimaki were higher than other ginseng cultivars. The root weight of American ginseng was heavier than others, but that of Russian ginseng was lighter. The num ber of leaflets per plant of 2-year-old plant and the root weight of 6-year-old plant were increased in order of Russian ginseng, American ginseng, Mimaki, Yellow-berry variant and Violet-stem variant.

• Journal of Ginseng Research
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• v.27 no.4
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• pp.202-206
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• 2003

This study was conducted to compare the growth status of aerial parts, photosynthesis and microclimate between fixing light transmittance (Control) and changing light transmittance (C.L.T.) during ginseng growing seasons. Control showed 8％ light transmittance rate during growing seasons. But C.L.T. showed 18％ light transmittance rate during early (April-June) and late growth stage (September-October) and 6％ light transmittance rate middle growth stage(July-August). Air temperature, leaking water rate and soil water content of C.L.T. was higher than those of control during early and late growth stage. But Air temperature, leaking water rate and soil water content of C.L.T was lower than those of control during middle growth stage C.L.T. exhibited superiority in survival ratio, stem diameter, stem length, L.A.I. and stem angle compared to control. Chlorophyll content of C.L.T. was lower than that of control but S.L.W., stomatal opening and photosynthetic rates of C.L.T. was higher than those of control. Also Alternaria blight disease and defoliation of C.L.T. was lower than those of control.

• Journal of Ginseng Research
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• v.26 no.2
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• pp.85-88
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• 2002

This study was carried out to obtain information of the photosynthetic rate at various temperature and light intensity, stomata, chlorophyll, specific leaf weight, characteristics of aerial part and root in ginseng new cultivars developed by pure line selection. The light saturation point of leaves in new cultivars and Jakyungjong were 15,000 lux, and the optimum air temperature on the photosynthesis of new cultivars and Jakyungjong were 20$\^{C}$. The photosynthetic rates were increased in order of Jakyungjong, Gopoong, Chunpoong and Yunpoong. The dark respiration rate of leaves in ginseng cultivars were increased according to the increasing of temperature, and the dark respiration rate of leaves of Yunpoong was the highest among cultivars. The specific leaf weight (SLW) were increased in order of Jakyungjong, Yunpoong, Gopoong, Chunpoong, but total chlorophyll contents were not different among cultivars. Stomata frequency of Yunpoong was the highest being 69.2ea among cultivars, while the length of stomata was reverse. Yunpoong was superior in aerial part among ginseng cultivars : the number of stem was 1.8ea, the number of palmately leaves was 7.7ea, the number of leaflets was 41.0ea, leaf area was 12.3 dm$^2$ The root weight were increased in order of Jakyungjong, Gopoong, Chunpoong and Yunpoong. Chunpoong and Gopoong hove good root shape the length of tap root in Chunpoong and Gopoong were the longest being 6.5 cm and 6.8 cm respectively, but that in Yunpoong was the shortest being 4.4 cm.