• Journal of Crop Science and Biotechnology
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• v.11 no.2
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• pp.119-126
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• 2008

Since somatic embryogenesis combined with ethylmethane sulfonate(EMS) treatments is the most efficient technique for mutagenesis, the embryogenic capacity of four soybean cultivars was evaluated at different EMS concentrations, treatment times, and preculture durations. Two to 4 mm long immature cotyledons were placed in induction medium after EMS treatment, and the numbers of somatic embryos formed per explant were counted four weeks after culture initiation. We observed genotypic differences in the efficiency of somatic embryogenesis from immature embryos among four cultivars treated with different concentrations of EMS for six hours. Cultivars, Sinpaldalkong 2 and Jack, displayed highly efficient somatic embryogenesis regardless of EMS concentration, whereas very low efficiency or no survival was observed in Jinju 1 and Iksannamulkong cultivars. Preculture duration did not influence the efficiency of somatic embryogenesis. Because Sinpaldalkong 2 exhibited the best somatic embryogenesis, much higher concentrations of EMS were used to test somatic embryo formation under different periods of time in this cultivar. Three and six hour treatments with both 1 and 2 mM EMS yielded higher embryo formation than longer periods of time. Increasing the time with embryos in 2 mM EMS caused a reduction in somatic embryogenesis in Sinpaldalkong 2, but many chlorophyll-deficient soybean variants were identified in the $M_1R_0$ and $M_2R_1$ generations. In addition to Jack, Sinpaldalkong 2 is a good genotype for plant regeneration from EMS-treated immature embryo cultures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.321-329
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• 1999

The effect of water deficits on soybean [Glycine max (L.) Merr.] could appear on seed quality through changes of morphological plant characteristics. Two Korean genotypes, Hwangkeum (determinate growth habit) and Muhan (indeterminate growth habit), were used to examine the influences of treatment stage and method of water deficit during reproductive growth period on yield and seed quality of soybean. Water deficit at R5 or R6 stages was as damaging to seed quality as double water-deficit treatments at R2+R5 or R2+R6. However, seed from double water-deficit treatment tended to have lower oxidation-reduction potential compare to the corresponding single water-deficit treatment. In comparison with Muhan, Hwangkeum had significantly greater oxidation-reduction potential value. Seed yield per plant in both genotypes depended greatly on seed yield of branches. However, the proportion of number of branch seed to total seed umber in Hwangkeum was increased as the water deficit was applied during later reproductive stage, whereas, in Muhan the proportion was lower. Water-deficit treatments including the single and double water-deficit treatments and non-stressed treatment were able to be classified into five groups for Hwangkeum and four groups for Muhan based on the influences on yield components, number of pod, number of seed, and single seed weight, using principal component analysis. In both genotypes, R2+R5 water-deficit treatment decreased number of pod and seed, but increased single seed weight. On the contrary, R6 or R2+R6 stress increased the pod and seed number, but decreased single seed weight.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.410-414
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• 2004

To understand the postharvest characteristics of soybean sprouts, 5-day-old sprouts were harvested, packed in PE film, and stored at 4, 12, and $20^{\circ}C$ for up to 4 days. In addition, the sprout respiration rate was measured after storage at 4, 8, 12, 16, 20, and $24^{\circ}C$ for up to 20h. During the first day of storage at $20^{\circ}C$, the sprouts maintained temperature-dependent longitudinal growth, especially of hypocotyl length; hypocotyl and root grew 0.8cm and 0.2cm, respectively. The hypocotyl thickness decreased by 11, 13, and $18\%$ after 4 days of storage at 4, 12, and $20^{\circ}C$, respectively. No temperature-dependent differences in fresh weight, dry weight, or water content were found, despite decreases of $3\%$ over the 4 days of storage. A significant postharvest decrease of $50\%$ in vitamin C content was observed in the sprouts stored at $20^{\circ}C$ for 3days. Based on the $CO_2$ production rate, the soybean sprouts exhibited an increase in respiration in proportion to the storage temperature; sprouts stored at 8, 12, 16, 20 and $24^{\circ}C$ showed approximately 2, 5, 6, 11, and 17 times, respectively, than the respiration rate of sprouts stored at $4^{\circ}C$. These results indicate the importance of low temperature storage during market circulation for minimizing the postharvest morphological and nutritional degradation of soybean sprouts.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.278-284
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• 1994

The sulfur amino acid composition in soybean (Glycine max L.) seeds may be an essential characteristic of new cultivars for some animal diets. Variation in seed storage protein among genotypes might make it possible to improve the quality of seed protein by genetically altering seed storage protein composition through plant breeding. This study was carried out to determine if mutant strains have potential for improving seed protein quality in soybean. Ten mutant strains had a distinct characteristic of seed storage protein subunits. Among the mutant strains, the sulfur amino acid compositions(methionine plus cystein) of Keburi(P.I.417016), Keburi(P.I.506817), and P.I.54608-1 were relatively higher than those of the others and were 1.9, 2.1, and 1.8%, repectively, which might be due to low levels of ${\alpha}$, ${\alpha}$', and ${\beta}$ subunits of 7S protein. Therefore, it is concluded that the mutant strains, Keburi(P.I.417016), Keburi(P.I.506817), and P.I.54608-1 appear to be potential materials for a breeding program for improving sulfur amino acid composition, and the others also seem to be possible breeding materials for other uses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.1-6
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• 1989

Three growth regulators, TIBA (2. 3. 5-Triiodobenzoic acid). ABA(Abscisic acid) and DGLP were sprayed on soybean plants sown on April 25 and May 10 to investigate those effect on growth and yield of Hwangkeumkong cultivar. TIBA or ABA reduced stem length. and lodging. however. increased stem diamater podding rate. number of pods and seeds per plant, and seed yield. Among 3 growth regulators TIBA was most effective to healthy growth and to increase of seed yield. Optimum treatment method for healthy plant growth and higher grain yield was 2-3 times spray with 5-day interval from 6 leaf stage (V6) of soybean plants. Soybean seed yield in the plot of TIBA treatment with 3 times from 6 leaf stage was 20% higher both in early and ordinary seeding field than those of non-treatment plots.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.134-142
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• 2017

Crop production in rice paddy fields is of great importance because of declining rice consumption and the low self-sufficiency ratio for field crops in Korea. A controlled drainage system (CDS) is recognized as an effective means to adjust water table (WT) levels as needed and control soil water content to improve the soil environment for optimum crop growth. The present study evaluated the effects of a CDS on soil characteristics, including soil water distribution and soybean development in paddy fields. The CDS was installed with two drain spacing (3 m and 6 m) at the experimental paddy field at the National Institute of Crop Science, Miryang, Korea. It was managed with two WT levels (0.3 m and 0.6 m) during the growing season. Soil water content, electrical conductivity and plant available nitrogen content in the soil were significantly greater in the 0.3 m WT management plots than in the 0.6 m plot and the control. At the vegetative stage, chlorophyll content was significantly lower with higher WT control because of excess soil moisture, but it recovered after the flowering stage. Soybean yield increased with WT management and the 0.6 m WT treatment produced the greatest grain yield, $3.38ton\;ha^{-1}$, which was 50% greater than that of the control. The CDS directly influenced outflow through the drains, which significantly delayed nutrient loss. The results of this study indicated that WT management by CDS can influence soil characteristics and it is an important practice for high yielding soybean production in paddy fields, which should be considered the crop growth stages for stable crop production.

• Applied Biological Chemistry
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• v.17 no.4
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• pp.240-246
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• 1974

The Merit variety of soybean (Glycine max L.), harvested in 1971 was germinated in the dark at $21{\sim}25^{\circ}C$ for days. The soybean sprouts were divided into cotyledons and seedling axis (=hypocotlyplus root) and subjected to the determination of dry weight, crude fat content and lipid components (esterified sterols, triglycerides, free fatty acids, free sterols and phospholipids) at two-day intervals during the germination periods. The results are summarized as follows: 1) During the germination period, the dry weight and crude fat content in cotyledons decreased continuously, but the dry weight seedling axis increased continuously and crude fat content remained almost constent. 2) The triglyceride content in crude fat from cotyledons decreased and free fatty acid content increased continuously, but triglyceride content in crude fat from seedling axis showed no change until 6th day and increased slightly after 8th day, and free fatty acid content showed increase after 4th day and decrease after 6th day. Phospholipids, free and esterified sterols content in cotyledons increased continuously, but their content in seedling axis remained unchanged.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.497-508
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• 2017

This study aimed to investigate correlations between concentrations of extractable Arsenic (As) with varying chemical solutions (0.1 M $Ca(NO_3)_2$, 0.1 M $(NH_4)2HPO_4$, 0.5 M EDTA, Mehlich 3, and 0.5 M $NaHCO_3$) and those of As in crops, and then to seek the most suitable soil extraction method for predicting the potential of As uptake in crops cultivated in soils contaminated with As. For a mesocosm experiment, pepper (Capsicum annuum L.), soybean (Glycine max L.), and rice (Oryza sativa L.) were cultivated for three months in pots containing soils taken from the arable areas near abandoned mines in Korea. Following the cultivation, soil pH and DOC significantly increased by treatments of lime and lime plus compost, respectively, while insignificant influences in changing total and all extractable As concentrations were found in all soils. Arsenic concentration in edible part of all crops considerably depended on the extractable As concentration in the soils, particularly with Mehlich 3. All extractable As concentrations in the soils of C. annuum and G. max were significantly correlated with As concentration in their edible parts. For O. sativa, the extractable concentrations of Mehlich 3 ($R^2$: 0.18 at p: 0.006) and EDTA ($R^2$: 0.11 at p: 0.036) showed only marked relationships with As concentration in the edible part. These results may indicate that the Mehlich 3 and EDTA are soil extractants to determine phytoavailable As in soil that provide better prediction for As transfer from soil to crop.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.493-497
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• 2000

An experiment was conducted to evaluate the possibility of using basic oxygen furnace (BOF) slag as soil conditioner in soybean upland field. In 1997, soybean (Glycine max L. cv. Eunha) crop was cultivated under different application rates of BOF slag at an experimental field of Chonnam Rural Development Administration in Nampyung, Najoo city. Five treatments, four application rates of BOF slag (0, 4, 8, $12Mg\;ha^{-1}$) and one application rate of lime ($2Mg\;ha^{-1}$) were tried with three replications. Plant height and shoot dry weight per plant were measured five times during the growth period. Chemical contents of soybean plant tissues and soil were also measured at the same sampling date. Yield were estimated by harvesting $6.6m^2$ per experimental unit and yield components were measured by sampling 10 plants per experimental unit at the harvest date. In upland soil, application of BOF slag rarely affected contents of total nitrogen, organic matter, available phosphate and potassium in soil. Soil pH, and contents of Ca and Fe in soil became higher as BOF slag rate increased. Enhancement of soil pH by application of BOF slag appeared to be closely related with increase in soil Ca content. Application rate of $2Mg\;ha^{-1}$ of lime showed almost the same effect in increase of soil Ca content as application rate of $4{\sim}8Mg\;ha^{-1}$ of BOF slag. Slag treatment hardly affected the contents of total nitrogen, $P_2O_5$, CaO, $K_2O$ and MgO in the shoot of soybean plants. Soybean plants under treatments of BOF salg showed better growth from the earlier growth stage compared with those of control treatment, and at the later growth stage, their growth was even superior to that of lime treatment. BOF slag rate of $8Mg\;ha^{-1}$ showed the highest soybean yield with $1,232kg\;ha^{-1}$. which was $330kg\;ha^{-1}$ or 37% higher than the yield of control with $902kg\;ha^{-1}$, As a result, BOF slag appeared to be useful material as a soil conditioner as well as nurient source for Ca and Fe in upland soybean fields, and its optimal rate for higher yield seemed to be around $8Mg\;ha^{-1}$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.78-83
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• 2008

Soybean [Glycine max (L.)] is a major source of protein for human and animal feed. Inter- and intra-genotype variation of soybean protein has been investigated by soybean researchers. However, limited sample amount of soybean single seed there is no report that investigated intra-plant variation of soybean protein within soybean plant. Recently a non-destructive NIR (near-infrared reflectance) spectroscopy using single seed grain to analyze seed protein was developed. The objectives of this study were to understand variation of seed protein content within plant and to determine the amount of minimum sample size which can represent protein content for a soybean plant. Frequency distribution of protein content within plant showed normal distribution. There was an intra-cultivar variation for protein content in soybean cultivar Seonnogkong. Difference of protein content among single plants of Seonnokong was recognized at 5% level. Seeds in lower position on plant stem tended to accumulate more protein than in higher position. There was significant difference for protein content between sample size 5 seeds and sample size of more than 5 seeds (10, 20, 30, 40, and 50 seeds) at a soybean plant with 57 seeds however no difference was recognized among sample size (5, 10, 20, and 30 seeds) at a soybean plant with 33 seeds. Around 20% seeds of soybean from single plant needed to determine the protein content to represent protein content of single soybean plant. This study is the first one to report evidence of intra-plant variation for proteincontent which detected by non-destructive NIR spectroscopy using single seed grain in soybean.