• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.279-283
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• 2004

This experiment was carried out at paddy field (commercial silty loam soil) in the southwestern Korea. Pungsannamulkong, a determinate growth habit, was a relatively high yielding and late maturing cultivar, and Han­namkong, a semi determinate growth habit, was a relatively low yielding and early maturing cultivar. Seeds were sowed at two plants and with a planting density of $70{\times}10cm$ on May 26, 2003. Fertilizer was applied prior to planting at a rate of 3.0-3.0-3.4g $(N-P_2O_5-K_2O)\;per\;m^2$ by all basal fertilizations. Experimental design was a randomized complete block with three replications. Seed yield was higher in Pungsannamulkong by 362g per $m^2$ than in Hannamkong of 260g per $m^2$ Also, the number of pod, number of seed, and number of seed per pod were greater in Pungsannamulkong than in Hannamkong. The number of leaves per $m^2$ showed similar with two soybean cultivars up to August 24 but thereafter it decreased in Hannamkong. The leaf area up to August 4 increased in Hannamkong higher than in Pungsannamulkong, but after that time, Pungsannamulkong had greater leaf area than Hannamkong. The shoot and leaf dry matter of two soybean cultivars from June 23 to August 4 were similar but thereafter, Pungsannamulkong had a significantly greater than Hannamkong. Crop growth rate (CGR), relative growth rate (RGR) and net assimilate rate (NAR) for Punsannamulkong were relatively higher than Hannamkong but leaf area ratio (LAR) and specific leaf weight (SLW) showed higher in Hannamkong. Most of leaves distributed in the ranges of 80-90cm and 60-70cm from the soil surface in Punsannamulkong and Hannamkong, respectively. Pods of Punsannamulkong ranged 10-80cm from the soil surface and most of pods were distributed at 40-50cm. Photosynthetic rate at the flowering stage showed a significant difference between cultivars in the upper most leaf position. There was no significant difference of the photosynthetic rate at $7^{tn}$ leaf at the flowering stage, and the uppermost and 7th leaf position at the seed development stage between two soybean cultivars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.311-318
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• 2002

Planting date of soybeans [Glycine max (L.) Merr.] is one of production components in cultural systems. The objective of the current study was to identify the components of soybean production and cultural practices encompassing planting dates and cultivars that respond to dry matter accumulation, harvest index and yield components. Three determinate soybean cultivars were planted on May 13 (early), June 3 (mid), and June 24 (late). Planting density was 60$\times$15cm with 2 seeds (222,000 plants per ha). Soybean plants were sampled every 10 days interval from the growth stages of V5 to R8 and separated into leaves including petioles, stems, pods, and seeds. Dry matter accumulations, harvest indices, and yield components were measured. Early planting had taken 55 days from VE to R2 and late planting taken 39 days indicating reduced vegetative growth. Early planting showed higher leaf, stem, pod and seed dry weights than late planting. However, late planting appeared to be higher harvest index and harvesting rate. Vegetative mass including leaf and stem increased to a maximum around R4/R5 and total dry weight increased to a maximum around R5/R6 and then declined slightly at R8. The highest seed yield was obtained with mid planting and no difference was found between early and late plantings. Cultivar differences were found among planting dates on growth characteristics and yield components. The results of this experiment indicated that soybean yield in relation to planting dates examined was mainly associated with harvest index and harvesting rate, and planting date of cultivars would be considered soybean plants to reach the growth stage of R4/R5 after mid August for adequate seed yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.228-235
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• 1995

This study was conducted to obtain the basic informations for developing new varieties and cultural techniques for vegetable soybean at the Crop Experiment Station, Rural Development Administration, Suwon, Korea in 1992. Two vegetable soybean varieties, 'Hwaeom-putkong' and 'Seokryangputkong', and the other 'Jangyeobkong' for soy-paste were planted at three planting dates(April 15, May 15, June 15). The characteristics of growth, yield, and quality were compared between vegetable and soy-paste soybean genotypes in response to different planting dates.Vegetable soybean varieties, 'Hwaeomputkong' and 'Seokryangputkong' were more resistant to lodging, earlier in maturity, higher in the density of pod set on stem and percentage of poded nodes, and larger in grain size than Jangyeobkong for soy-paste. Earlier planting (April 15) of vegetable soybean varieties increased the yield of green pod as well as improved quality in number of green pods per 500g and length and width of green pod.

• Parasites, Hosts and Diseases
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• v.43 no.4 s.136
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• pp.141-147
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• 2005

A practical and convenient method of rearing Eucyclops serrulatus in a microculture environment is described. A complete life cycle of E. serrulatus was maintained in a narrow space on a microscope slide glass on which a cover glass of $22{\times}40mm$ in size was mounted at a height of 0.8mm. The culture medium was constituted by bottled mineral water boiled with grains of Glycine max (soybean). Chilomonas paramecium, a free-living protozoan organism, was provided as live food. Growth of nauplii hatched from eggs to the first stage of copepodite took an average of 7.7 days, and the growth of copepodite 1 to the egg-bearing adult female took an average of 20.1 days in the microculture cell with an average life time of 44.7 days. Continuous passage of cope pods was successfully maintained as long as sufficient medium and food were provided. The microculture method enables an in situ microscopic observation on the growth and developmental process of helminth larvae experimentally infected to copepods as well as of copepod itself. Furthermore, it does not require anesthetization and, therefore, minimize the amount of stress exposed to cope pods during the handling process.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.150-153
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• 1978

A study was conducted to determine the critical period of weed-free maintenance required to produce maximum soybean yields. Leaf area index(LAI). crop growth rate (CGR), and number of pods per plant were increased with extended weed-free maintenance period. Consequently, maximum soybean yields were obtained when weeds were controlled for more than six weeks, but a relatively high level of ;soybean production was attained with only two weeks of weed free maintenance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.51-57
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• 1979

In order to screen the shade tolerance soybean lines, several important agronomic characters were studied after shade treatment at various growth stages. A severe influence of light reduction on agronomic characters found during the late flowering to pod filling period, and the response to shading was significantly different among the lines tested. Examining of pods number per plant after shade treatment during pod filling stage would be most effective method in the screening for shade tolerance soybean lines.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.220-225
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• 1991

Four cropping systems, soybean mono-cropping, Cassia tora mono-cropping, soybean-C. tora companion cropping and soybean-C. tora intercropping, were compared for number of soil nematodes and soybean growth in upland field in 1986. Soybean was cultivated as an after-crop of four different cropping systems from 1987 to 1989, and observations were continued. Soil nematode was not found in C. tora mono-cropping plot from mid growing season of C. tora while many nematodes were found in soybean mono-cropping plot in 1986. A few nematodes were found for 3 years in soybean field after one season cultivation of C. tora in 1986. Number of nematodes was lower in soybean-C. tora companion and inter-cropping plots compared with soybean mono-cropping, and was also lower for 3 years in soybean field after one season companion and inter-cropping culture in 1986 compared with continuous soybean cultivation plot. No root nodule was formed on C. tora root, but number of root nodules of soybean plant grown in C. tora companion and inter-cropping plots was not different with soybean mono-cropping plot. Number of pods. number of seeds and seed weight per soybean plant grown in C. tora companion and inter-cropping plots were almost same with soybean mono-cropping plot. When soybean was cultivated in field after one season C. tora mono, companion or inter-cropping, pod and seed number, and seed weight per plant were higher than continuous soybean cultivation field.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.71-80
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• 2017

This study was conducted to investigate the application effect of Lysobacter antibioticus HS124 (gelatinase and chitinase producing microorganism; GCM) for the improvement of soybean yield and control of stink bug. Our results showed that the yield of GCM-treated soybean increased by 17.0, 20.3, 19.0, and 25.6% in the experimental field sites of Muan-gun, Sunchang-gun, Gwangju 1, and Gwangju 2, respectively, compared to the yield of the soybean obtained by conventional practice treatment (CPT); however in the Gimjae-si, the yield decreased by 10.6%. Results in both pods and seeds $plant^{-1}$ were significantly increased in Gwangju 2 by the GCM cultured broth treatment (GCMT). Ratio of 3 seeds $pod^{-1}$ in Sunchang-gun was statistically significant between GCMT and CPT, however, the result in the other field showed no significance. Germination rate was only statistically improved by GCMT in Gwangju 2 field site. GCMT reduced the appearance of stink bug in all experimental field sites except in Gimjae-si. The soybean seed damage by stink bug was no significance in all of treatments. Therefore, GCMT could improve the productivity of soybean and also control the infestation of stink bug.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.359-363
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• 2014

Soybean seed is a good source of plant protein in human consumables such as baby formula and protein concentrate. The seeds contain an abundance of storage proteins, namely ${\beta}$-conglycin and glycinin that account for ~ 70-80% of the total seed protein content. Proteome profiling has been proved to be an efficient way that can help us to investigate the seed storage proteins. In the present study, the seeds were removed from the pods and the cotylendonary tissues were separated from the testa for proteome analysis in order to investigate the seed storage proteins. A systematic proteome profiling was conducted through one-dimensional gel electrophoresis followed by MALDI-TOF-TOF mass spectrometry in the seeds (cotyledonary tissue) of soybean genotypes. Two dimensional gels stained with CBB, a total of 10 proteins were identified and analyzed using MASCOT search engine according to the similarity of sequences with previously characterized proteins along with the UniProt database. A total of ten proteins such as glycinin Gy4 precursor, glycinin G3 precursor, glycinin G1 precursor, glycinin chain A2B1a precursor, glycinin chain A2B1a precursor were identified in our investigation. However, the glycinin subunit may be considered to play important roles in soybean breeding and biochemical characterization. In addition, the improved technique will be useful to dissect the genetic control of glycinin expression in soybean.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.329-333
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• 2006

Soybean quality is determined based on protein content, lipid content and fatty acid composition, and several functional components including isoflavones, anthocyanins and functional activity. Because the level of each component changes during seed development, it is necessary to know the concentration of quality-related components in developing seeds. Little is known of the pattern of changes in quality-related components. Seeds from field-grown soybean was harvest from the $R_6$ stage to the $R_8$ stage in 2004. Seed characteristics and the level of nutritional components were examined. Seed moisture content was dropped rapidly after the $R_7$ stage in the tested varieties. Seed growth rate was the highest from the beginning of the $R_6$ stage to the mid-$R_6$ stage. Chlorophyll content was decreased rapidly in pods and seeds. However, seed growth period from the $R_6\;to\;R_8$ was 35 days. The crude protein content was. increased dramatically between 63 DAF and 70 DAF and then increased slightly. The pattern of isoflavone accumulation was nearly similar to that of seed weight increase. From the late $R_6$ stage to the $R_7$, the accumulation rate was higher as compared to other stages. The angiotensin inhibitory activity was increased according to seed development from 63 ($R_6$) to 84 DAF ($R_8$). The difference of inhibitory activity in heated soybean powder, however, was not great among stages. The inhibitory activity was affected by heating treatment. The most effective heating time was 10 min. Excessive heating longer than 30 min resulted in a lowered inhibitory activity of soybean on ACE.