• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.324-329
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• 1993

Effects of leaf and pod removal on changes in leaf and seed number, and leaf, seed, pod and stem dry weight of soybean [Glycine max (L,) Merr.] cultivar ‘Hwangkeumkong’ were measured at the research farm of Korea University in 1992. The upper 40% and lower 60% of leaves and pods were subjected to treatments at the growth stage of beginning pod(R3). Leaf number and dry weight of lower part were increased by upper leaf-lower pod removal, but seed number and dry weight were decreased. Upper leaf-lower pod removal increased lower stem dry weight and decreased upper pod dry weight. Leaf-seed ratio of the upper leaf-lower pod removal was the highest with 3.54 and harvest index was the lowest with 27% among the treatments. Lower leaf-upper pod removal showed that more assimilates from upper leaves were translocated to lower seeds than from lower leaves to upper seeds in upper leaf-lower pod removal treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.723-730
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• 1995

Effects of leaf and pod removal on changes in dry weight and protein content of soybean [Glycine max (L.) Merr.] cultivar 'Hwangkeumkong' were measured at the research farm of Korea University in 1992. The upper 40% and lower 60% of leaves and pods were subjected to treatments at the growth stage of beginning pod(R3). Leaf dry weight of lower part was increased by upper leaf-lower pod removal, but seed dry weight of upper part was decreased. The upper leaf-lower pod removal also increased stem dry weight and decreased upper pod dry weight. Protein content was higher in lower leaves than upper leaves. Seed protein contents were decreased both upper leaf-lower pod removal and lower leaf-upper pod removal treatments. The upper leaf-lower pod removal showed the highest leaf and the lowest seed protein quantities among the five treatments. These results indicated that protein sources were moved from lower to upper parts but weak in remobilization from leaves for the long distance translocation during the reproductive growth period of soybean plants.an plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.371-381
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• 1995

The effects of leaf and pod removal on variation of nodal sink components in determinate soybean [Glycine max (L.) Merr.] cultivar 'Danyeobkong' were measured at the experiment field of Chonbuk Provincial Rural Development Administration in 1991. Contrary to the conventional numbering system, node order in this experiment was numbered from top to bottom node. The leaves and pods of main stem from terminal to 5th node, below 6th node, or branches were removed at the growth stage of beginning pod(R3). In the leaf removal treatment, number and weight of pod and seed were highly decreased in upper part leaf removal, especially in removed part. In the pod removal treatment, number and weight of pod and seed were slightly increased in the other part. Cracked seed coat ratios were also high in the leaf removal treatment compared with control but low in the pod removal treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.377-382
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• 1993

Effects of leaf and pod removal on changes in dry weight and on the contents of soluble sugar, starch, protein and oil in leaves and seeds of soybean [Glycine max(L.) Merr.] cultivar ‘Hwangkeumkong’ were measured at the research farm of Korea University in 1992. The upper 40% and lower 60% of leaves and pods were subjected to treatments at the growth stage of beginning pod(R3). Upper leaf-lower pod removal showed the highest leaf and the lowest seed dry weights. Soluble sugar content was no different among treatments in leaves and seeds. The highest starch content was found in leaves of upper leaf-lower pod removal. Protein content was higher in lower leaves than upper leaves and the lowest in seeds of lower leaf-upper pod removal which had the highest oil content in leaves and seeds. These results apparently indicated that photoassimilates were mobilized from upper leaves to lower seeds, and protein sources were moved from lower to upper parts but weak in remobilization from leaves for the long distance translocation during the reproductive growth period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.6
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• pp.594-601
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• 1994

Effects of translocation on seed yield and carbon-nitrogen compounds at five leaf-pod ratios of soybean [Glycine max. (L.)Merr. ] culti bars, 'Paldalkong', 'Baekunkong', and 'Danyeobkong' were measured. The upper 50 and lower 50% of leaves and pods were subjected to treatments at growth stage R3. Three soybean cultivars showed the similar trends on changes in dry matter accumulation and on the contents of soluble sugar, starch and protein in seeds among the treatments. Mean stem dry weight was increased with upper leaf-lower pod and lower leaf-upper pod removals, and decreased with upper leaf and lower leaf removals. Leaf dry weight was appeared higher at the upper leaves among the treatments. Seed numbers and dry weights were decreased with leaf and leaf-pod removals, and were higher in lower part of the plants. Soluble sugar and starch contents in seeds were also showed slightly higher in lower part. Protein content of seeds was decreased in upper part with upper leaf removal and in lower part with lower leaf removal, however, that of the upper seeds was the highest with lower leaf removal. The results of this study are assumed that carbon and nitrogen compounds were translocated opposite directions and protein source was weak in remobilization for the long distance transport during the reproductive growth period of soybean plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.16-25
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• 1995

The effects of leaf removal time on variation of nodal sink components in determinated soybean ［Glycine max （L.） Merr.］ cultivar 'Danyeobkong' were measured at the experiment field of Chonbuk Provincial Rural Development Administration in 1991. Node order in this experiment was calculated from terminal node to bottom node to clarify the photosynthetic ability of canopy leaves. The upper 5 leaves from terminal node of main stem were removed at 5, 15, 25, 35 and 45 days after flowering(DAF) respectively. In spite of light-receiving increment in lower part of main stem and in branch by removing the upper part leaves of main stem, seed weight of that part was not increased in leaf removal treatment compared with control block. The node position reducing pod went down from terminal to bottom by delaying leaf removal time, and the influence of pod number reduction was bigger in DAF 25 than in DAF 15. But the seed number reduction per pod was the biggest in DAF 35. Cracked seed coat ratio ranged from 25% to 35% in control block, while that of leaf removal block had mostly 10% gap compared with the control block.rol block.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.159-165
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• 1993

To clarify the effects of sink demand for assimilate on leaf photosynthetic rate, tissue composition, and leaf senescence of soybean [Glycine max (L.) Merr.] J plants, pod and leaf tissues were removed at growth stage $R^3$. Plant responses were measured every 10days from 2 through 42days following treatment. Leaves of depodded plants exhibited increased starch and chlorophyll contents and specific leaf weight. Stomatal resistance was also increased and leaf photosynthetic rate was reduced. Dry weight of vegetative tissues except leaves was increased by pod removal. Leaf removal resulted in a decreased starch content of leaves from 22 to 42days after treatment and that of roots at all sampling times. Specific leaf weight was decreased while leaf photosynthetic rate was increased. Stomatal resistance and chlorophyll content were little affected. Weight per seed was decreased 3.0% by leaf removal. Except for the seed, tissue protein contents were increased by pod removal but decreased by leaf removal, however, seed protein content was not affected by either. Apparent senescence was delayed by depodding. Both apparent and functional senescence were accelerated by leaf removal.

• Proceedings of the Korean Society of Crop Science Conference
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• 1993.10a
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• pp.54-55
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• 1993

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.431-435
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• 1987

Terminal bud removal has been thought as a useful practical management of soybean cultivation in Korea, and such cultivating method has been recommended till recent times. Many experiments about the effect of bud removal have been made, but it is not certain yet. This study was conducted to determine if source potential and seed yield would be affected by bud removal in 4 determinate soybean varieties. Terminal bud was removed by hand at the 5 trifoliolate stage of growth. Data were collected on leaf area and leaf dry matter weight from 58 to 101 DAP by nearly every 10 days and some agronomic characteristics and seed yield after maturity. Removing the apical bud did not increased leaf area and leaf dry matter. Number of modes and pods per a plant was increased by bud removal, but number of seeds per a pod was decreased, and seed yield was unchanged by such offsets. From the data, we concluded the source potential of soybean plants was not increased by terminal bud removal under the planting density, 22,000 pit/l0a, however it would be a useful way to reduce the lodging or over-growth.

• Journal of Plant Biology
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• v.17 no.3
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• pp.127-136
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• 1974

The effect of potassium metabolism on the soybean leaves was studied with comparison of other elements during the successive growing period. The results were as follows; 1. The percentage of potassium content showed remarkable increase not only in the first compound leaf at a stage which was growing vigorously and producing new leaves, but also in the fifth compound leaf at a stage which was taking a active metabolism of nitrogen and carbohydrate but not producing new leaves. However, the percentage of potassium content was decreased in the second compound leaf than in the first one. Such a result could be regarded as a potassium removal from mature leaves into immature and flowing out from stoma through respiration. During the pod-development the percentage of potassium content in the soybean leaf was decreased. 2. If nitrogen, phosphorus and potassium were added excessively in the nutrient solution, the percentage of potassium content in the soybean leaf had increased. The effects of these elements showed a remakable increase in the excessive plot of nitrogen than in that of phosphorus. At early stage the redtarded effect of phosphorus on the growth of soybean could be covered by potassium, however, at late stage it could not. The growth of soybean plant was much more inhibited by potassium, compared with nitrogen and phosphorus. New leaves could not be produced in the potassium deficient soybean plant after the third compound leaf. The normal growth of soybean plant could not be observed if only one element was excessively added to the culture solution, compared with the deficiency of other two elements.