• Korean Journal of Weed Science
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• v.32 no.1
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• pp.17-24
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• 2012

The study was conducted to investigate the effect of weed interference and starter fertilizer on subsequent soybean seed quality at the Agricultural Research Farm and Laboratory of Razi University, Kermanshah, Iran. Two factorial experiment was laid-outon a randomized complete block design with four replications. First factor was starter fertilizer levels (0 and 25 kg $ha^{-1}$) applied in the forms of monoammonium phosphate, the second factor was different weed interference periods consisted of five initial weed-free periods (in which, plots were kept free of weeds for 0, 15, 30, 45 and 60 days after crop emergence (DAE) and then weeds were allowed to grow until harvest) and five initial weed-infested periods (in which, weeds were allowed to grow for 0, 15, 30, 45 and 60DAE, after which the plots were kept free of weeds until harvest). Full season weedy condition reduced 100-seed weight, seed germination percentage and seedling dry weight by 25.9, 13.3 and 22.5%, respectively and increased mean germination time and seed electrical conductivity by 55.8 and 24.3%, respectively as compared with full season weed-free control. However, the traits under study were not significantly influenced when field was kept free of weeds for at least 45 DAE (R1) or weedy condition was continued for less than 30 DAE (V8). There was a significant and negative correlation between weed biomass and seed weight (r = -0.93), so that when weed free condition was less than 45 DAE or weed infested period was continued for at least 30 DAE, soybean plants produced wrinkled and underdeveloped seeds with lower weights and qualities. Moreover, soybean seed quality reduction due to weed interference was more evident when starter fertilizer was applied and weeds interfered with soybean from the beginning of the growing season. Information from the present study is beneficial in soybean seed production systems and where farmers use the harvested seeds for the following planting.

• 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 Breeding Science
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• v.42 no.1
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• pp.35-39
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• 2010

Soybean proteins are widely used for human and animal feed in the world. ${\beta}$-conglycinin protein exhibits poor nutritional and food processing properties and Kunitz trypsin inhibitor (KTI) protein is a main anti-nutritional factor in soybean seed. The objective of this research was to identify the inheritance of $cgy_1$ gene and ti gene for the improvement of soybean cultivar with no KTI proteins and low amount of ${\beta}$-conglycinin. $F_2$ population was made by crossing between "Gaechuck2ho" (${\alpha}^{\prime}$-subunit present $Cgy_1Cgy_1$, KTI protein absent titi) and PI506876 (${\alpha}^{\prime}$-subunit absent $cgy_1cgy_1$, KTI protein present TiTi) parent. A total of 434 $F_2$ seeds were obtained and analyzed for the segregation of ${\alpha}^{\prime}$-subunit protein and KTI protein using SDS-PAGE. The segregation ratio of 3 : 1 for $Cgy_1$ locus (310 $Cgy_1$_ : 124 $cgy_1cgy_1$) and Ti locus (339 Ti_ : 95 titi) were observed. Segregation ratios of 9 : 3 : 3 : 1 (241 $Cgy_1$_Ti_: 69 $Cgy_1$_titi: 98 $cgy_1cgy_1$Ti_: 26 $cgy_1cgy_1titi$) between $Cgy_1$ gene and Ti gene in $F_2$ seeds were also observed (${\chi}^2= 5.367$, P = 0.10 - 0.20). This data showed that $Cgy_1$ gene was inherited independently with the Ti gene in soybean. These results will be useful in breeding program for selecting the line that does not exhibit or lacks both ${\alpha}^{\prime}$-subunit protein and KTI protein in soybean.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.1-7
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• 1993

The 1,081 soybean genotypes including 972 black soybeans and 109 other colored soybeans were collected in 197 locations from January to April, 1991. Seed chemical components of soybean collections in relation to growth characters were evaluated to survey germplasms for black soybean breeding for seed quality. Seeds of 1,081 genotypes collected were analyzed for crude protein, crude lipid, and total sugar contents. The crude protein content was averaged to 39.8% and ranged from 34.1% to 48.0%. The average crude lipid and total sugar contents were 20.1% and 10.1%, and the ranges of those were 14.1% to 23.8% and 8.3% to 12.1%, respectively. Higher crude protein content was shown in early soybean maturity group, whereas higher total sugar content was in late group. Black soybean collections with green seed embryo tended to be higher in total sugar content than those with yellow one. Black soybean oil is generally composed of about 22% oleic, 55% linoleic, 7% linolenic acid, and 16% the others.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.123-127
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• 2004

This study was conducted to determine the effect of food combinations of leguminous seeds on the nymphal development and adult fecundity of Riptortus clavatus Thunberg. Nymphal duration ranged from 20 to 28 days depending on food combinations with the shortest on the seed of soybean (Glycine max Linnaeus), soybean + kidney bean (Phaseolus vulgaris Linnaeus) and soybean ＋ peanut (Archis hypogaea Linnaeus) and the longest on the seed of kidney bean. Instar duration was longer with increasing instar from 2.4 to 2.5 days in the 1st instar to 5.3 to 7.3 days in the 5th instar Accordingly, instar duration was significantly different on food combinations exception of 1 st instar Percent emergence varied from 3.5％ on peanut to 65.0％ on the seed of soybean ＋ peanut. Nymphal mortality was the highest in the 1 st instar regardless of food combinations. Adult longevity was in range of 5.5 days to 11.2 days which was the shortest on the seed of kidney bean+peanut and the longest on soybean ＋ peanut and was about 8.0 days on the other food combinations. Total number of eggs laid by female was most on soybean+peanut and was least on kidney bean ＋ peanut. Accordingly, it can be recommended that food combination of the seed of soybean ＋ peanut was the best and then was soybean only while other food communications of leguminous seeds was hard to use for mass rearing of R. clavatus.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.13-13
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• 2019

Soybean (Glycine max L. (Merr) is commonly consumed and found in major foods including soymilk, soy sauce, tofu, and soy sprout in Korea and east Asia. In addition, it is common to cook the whole seeds with rice. Soybean is known to have ranges of health benefits including antiaging, anticancer, neuroprotective and antidiabetic taken either as supplement or dietary food. Anthocyanins and flavonoids in G. max are found to be the main contributors to such wide arrays of health benefits. Due to increasing economic values of soybean, development of specialty soybean cultivars is becoming an area of interest worldwide. In this study, 746 black soybean accessions from National Agrobiodiversity Center were characterized as part of an attempt to identify important germplasms of G. max. Seed coats of each accession were analyzed for their total anthocyanin, cyanidin 3-O-Glucoside (C-3-O-G), delphinidin 3-O-glucoside (D-3-O-G), petunidin-3-O-glucoside (Pt-3-O-G), and their whole seeds for crude protein contents. HPLC was used to determine and quantify the anthocyanin compositions while crude protein was determined using Kjeldahl method by Kjeltec auto-analyzer (Kjeltec 8400, Foss, Sweden). Accessions were grouped according to their anthocyanins and protein contents; the mean content of which were correlated to agronomic traits including maturity date, one hundred seed weight, cotyledon color and seed lust color. The results indicated that the total anthocyanin content (TAC) ranged from 273.77 to 6250.52 mg/100 g, with mean value of 1853.03 mg/100 g while the crude protein content (CPC) being between 33.43 and 47.51%, with mean value of 40.81%. The highest number of accessions (45.97%) showed TAC between 1000~1900 mg/100 g while 30.96% of accessions showed CPC between 41~43%. Among the 746 accessions considered, 11 (IT142935, 175818, 175855, 177191, 177209, 177211, 177214, 177216, 177218, 177220, 177274) of them showed TAC above 4000 mg/100 g. C-3-O-G was found to be the major contributor to TAC showing strong correlation. Accessions with green cotyledon color showed high mean TAC compared to those having yellow cotyledon color, and accessions with dull seed lust color showed high mean TAC than those having shiny seed lust color. One hundred seeds weight and maturity date showed positive correlation with all anthocyanin contents, except for Pt-3-O-G in the latter case. The overall result of the present study could be used as background for developing new black soybean cultivars and breeds with high anthocyanin and protein contents. The result depicted that many of the accessions could be used as potential parental lines.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.50-56
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• 2001

Thirty-three bacterial and fungal strains were isolated from the rotten soybeans and soybean sprouts to isolate pathogenic microorganisms which cause soybean sprouts rot during soybean sprouts cultivation. In pathogenicity tests of the isolates on soybean sprouts, two isolates(K-17 and K-28) caused soybean sprouts rot and were identified as Erwinia carotovora and Fusarium sp., respectively. To isolate antagonists aganist K-17 and K-28 pathogens, bacteria were isolated from various soybean-cultivated soils and screened by the inhibition zone method. A bacterial isolate(J-232) which inhibited growth of both pathogens was identified as Pseudomonas fluorescens and further examined. The culture filtrate of P. fluorescens J-232 (dilution rate of 500 times) inhibited the growth of Erwinia carotovora K-17 and Fusarium sp. K-28 both on potato dextrose agar medium and on soybean sprouts cultivated in vessel. The development of soybean sprouts rots was observed during cultivation by inoculation of soybean seeds with culture filtrate of both pathogens. The combined inoculation of soybean seeds with culture filtrate of antagonistic bacterium and that of pathogens prevented soybean sprouts rot, and the growth of soybean sprouts was similar to that of control. The soybean sprouts inoculated with antagonists culture filtrate alone did not develop soybean sprouts rot, and the growth of the seedlings was shown to be slightly promoted as compared with that of control.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.178-187
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• 1996

This study was conducted to obtain the basic informations for producing high quality seeds of vegetable soybeans. Four vegetable soybean cultivars, 'Okharawase', 'Mikawashima', 'Hwaeomputkong', and 'Seokryangputkong' were planted at four locations, Chulwon(altitude, 192m) and Pyeongchang(altitude, 370m) in highland, and Suwon(altitude, 37m)and Daegu(altitude, 55m) in lowland of Korea with two planting dates, May 15 and June 15. Seed infection rates were attributed by in order of phomopsis seed decay caused by Phomopsis spp., seed mottling caused by soybean mosaic virus (SMV), purple seed stain caused by Cercospora kikuchii. Seed infectron rate was the lowest at Pyeongchang and lower on June 15 than on May 15 planting. Phomopsis seed decay by Phomopsis spp. was lower in highland of Korea, Pyeongchang and Chulwon, than in lowland of Korea, Suwon and Daegu. Seed infection rate was also lower on June 15 planting than on May 15, and in seeds harvested at maturity than at ten days after maturity. Germination rate of seeds harvested in highland, Pyeongchang and Chulwon, after six to seven month storage at 5$\pm$1$^{\circ}C$ was more than 90% and higher than that of the seeds in lowland, Suwon and Daegu. Germination rate was also higher on June 15 than on May 15 planting.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.47-53
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• 1977

Bacterial diseases of soybean has been recognized as a limiting factor of soybean production in Korea as it was estimated to cause around 10 percent of yield losses annually. The purpose of the study is to obtain information on the diseases through proving the kinds of pathogens and epidemiology, The wire brush method and multineedle appeared to be the best way of inoculation under all circumstances. Wire brush method, especially, was effective in shortening the incubation period and manifesting the lesion development by introducing more inoculum per unit of area. In case of spray inoculation it was necessary to apply a small amount(1 : 1,000) of wetting agent, twin-20, otherwise it was unabled to produce the diseases under field conditions. Two kinds of bacterial diseases caused by Pseudomonas glycinea and Xanthomonas phaseoli var. sljense were found from surveyed areas in Kore. Wild fire disease on soybean caused by Pseudomonas tabaci had not detectable during the experiment although there were several reports on the disease from other countries. when the pathogens were introduced into sterile soil, bacterial leaf blight pathogen could exsisted until 30 days while bacterial pustule pathogen survived only 4 days under the natural conditions of later June. Both bacteria, however, could produce the disease after more than 10 months period of storage in refrigerator when they were exsisted in infected plant tissues. In warehouse, non-temperature controlled, the bacteria lose their infectability within 6 months period from October to April even though they exsisted in infected tissues. Surface infested seeds with the pathogens could not produced the diseases on seedling stages of soybean plants when the seeds were planted in sterile soil after inoculation by dipping the seeds into bacterial suspensions, although germination was depressed by the pathogens when the seeds were planted on agar media.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.4
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• pp.291-300
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• 2005

This study was focuses on the variation of isoflavone contents during seed development and their interaction with major chemical components such as protein, amino acids, saccaharides, lipid and fatty acids. During maturing, lipid, protein, and amino acid contents in soybean seeds showed the highest values at R7 stages, but isoflavone contents were increased until R8 stage. It was noted that malonyl glucosides $(64.2\%)$ are predominant forms among conjugated isoflavones followed by glucosides $(30.7\%)$, acetyl glucosides $(4.1\%)$ and aglycones $(0.9\%)$. Sucrose and stachyose were presented as a major saccharide in soybean seeds. As maturing days progressed, they were constantly increased and the highest contents were observed at R8 stage. While small quantities of raffinose, fructose, glucose, maltose, DP3 (DP: degree of polymerization), DP6, and DP7 were detected. These results showed that saccharide composition at the beginning of seed development is primarily monosaccharides with little sucrose and oligosaccharides, but as maturing days proceeds, sucrose and starch increase with concomitant decrease in monosaccharides. Sucrose and stachyose were positively correlated with isoflavone (r=0.780, 0.764 at p<0.01, respectively), while fructose, glucose, maltose, and DP7 were negatively correlated (r=-0.651, -0.653, -0.602, and -0.586 at p<0.05, respectively). Soybeans at R8 stage were high in protein and amino acid, but low in free amino acid contents. Protein and amino acid contents showed positively significant correlations with isoflavone (r=0.571 and 0.599 at p<0.05, respectively), but free amino acid content were negatively correlation with isoflavone (r=-0.673, p<0.01). The lipid content reaches its final content relatively early stage of seed development and remains constant as compared with other chemical components. Among the fatty acids, although varietal difference was presented, stearic acid and linolenic acid were gradually decreased, while oleic and linoleic acid were increased as seed maturing progressed. Lipid was significantly correlated (r=0.754, p<0.01) with isoflavones. However, neither saturated fatty acid nor unsaturated fatty acids significantly affected the isoflavone contents of maturing soybean seeds.