• Research in Plant Disease
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• v.21 no.3
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• pp.243-249
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• 2015

Soybean frogeye leaf spot caused by the fungus Cercospora sojina Hara, has known to lead a severe reduction of crop yield. Since frogeye leaf spot on soybean has recently become a serious problem in Korea, the susceptibility of recent recommended cultivars against C. sojina had been tested. To standardize the disease severity of soybean, the optimum sporulation condition of C. sojina and the disease index were established in this study. Sporulation was maximized on the 10% V8 juice agar with 12 h light and 12 h dark at $25^{\circ}C$. Spore suspension ($10^5spores/ml$) was sprayed on the leaves of soybean (V6 stage), and the disease responses to each isolate were evaluated on 28 days after inoculation. As a result, Daepung, Shinpaldal2ho, Yeonpung and Cheonga showed the resistance reaction to 8, 7, 6, 6 isolates of C. sojina, respectively, whereas Cheongja, Hwangkeum, Taekwang, Daewon, Cheonsang and Sinhwa showed the susceptible reaction to 8 isolates of C. sojina. Breeding the resistant soybean cultivars against C. sojina requires a uniform resistance for screening technique. The disease index of frogeye leaf spot on soybean developed in this study can be effectively used for the accurate field assay to select the frogeye leaf spot resistant soybean.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.05a
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• pp.76-77
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• 2001

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.44-48
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• 1998

Two determinate soybean cultivars, 'Baegunkong' and 'Namhaekong', were planted on 8 Jone, 23 June, and 8 July 1996 at Cheju at planting densities of 33, 43, 53, 63 plants per $m^2$ to determine the optimum planting density of double crop soybean for recently recommended cultivars in Cheju area at various planting dates. The plant height, and the diameter and node number of main stems decreased as planting was delayed. The plant height increased but the stem diameter and node number decreased with increasing planting density. Pod number per plant was greater for Namhaekong than for Baegunkong and was not affected by planting date. Pod number per plant decreased but pod numbers per $\textrm{m}^2$ increased with increasing planting density. The number of seeds per pod was greater at the two later plantings and fewer at the highest planting density. 100-seed weight decreased with delaying planting. The seed weight was lighter at the highest planting density for Baegunkong but there was no difference for Namhaekong among the planting densities. The seed yield of Baegunkong was greater for 23 June and 8 July plantings (2,280 and 2,420 kg/ha) than for 8 June planting (1,450 kg/ha) while that of Namhaekong was greatest at 23 June planting (2,690 kg/ha) compared with 8 June and 8 July plantings (1,890 and 2,080 kg/ha). Across the planting dates and cultivars, seed yield increased from 1,860 to 2,290kg/ha as the planting density increased from 33 to 53 plants/$\textrm{m}^2$ and then leveled off with a further increase in planting density.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.986-991
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• 2010

This study was conducted to investigate the changes of mineral, oxalate and phytate during tofu processing with Korean recommended soybean cultivars. Fourteen cultivars were selected by distribution of calcium, oxalate and phytate contents. Tofu was manufactured and analyzed for quality characteristics, mineral, oxalate and phytate contents. The yield and moisture contents of tofu ranged from 137.77% in Anpyeongkong to 201.91% of Geomjeongkong 4, and 74.42 (Bongeuikong)~80.01% (Hojangkong), respectively. The lightness (L-value), redness (a-value) and yellowness (b-value) ranged from 53.05 (Dawonkong) to 86.16 (Jipumkong 2), -2.04~5.85, and from 3.28 in Geomjeongkong 4 to 16.17 of Cheongjakong, respectively. The hardness of tofu with selected soybean cultivar ranged from 537.36 g (Dongpuktae) to 1696.05 g (Jinpumkong 2). The highest calcium content was 1.488 mg/g in Dawonkong, oxalate and phytate in tofu were high at 0.40 mg/g in Geomjeongkong 4 and 0.41 mg/g in Dawonkong, respectively. The transfer ratios of oxalate and phytate from soybean to tofu were ranged from 0.31~19.70 and 0.41~19.70%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.179-185
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• 1984

These studies were carried out to evaluate the feasibility of using Alkali Digestibility Value (ADV) of soybean seeds as a selection criterion for cooking quality of soybean grain with rice, and to find out an optimal testing condition, varietal differences in ADV and the effect of cultural environment on the ADV, and its mode of inheritance. The ADV test was achieved succesfully by soaking the soybean grain for 24 hours in 25 to 30% KOH solution at 25 to $30^{\circ}C$. Varietal differences in the ADV were conspicuous, but cultural conditions affected the ADV little. All collected lines for cooking with rice showed high ADV and all the small grain cultivars introduced from abroad had low ADV, while recommended cultivars showed great variation in ADV. The characteristic of low ADV in soybean grains was controlled by single dominant gene.

• Food Science and Preservation
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• v.9 no.2
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• pp.205-211
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• 2002

In order to selection of the suitable soybean varieties, the quality characteristics of meju and doenjang on 4 domestic soybean cultivars(Daeweon, Sodam, Jinpeum and Hwangkeum) were evaluated. Crude protein and lipid content was 26.7∼30.5% and 16.89∼19.31%. The content of total free sugar among 4 soybean cultivars were 4.99∼5.26% and composed mainly stachyose(2.59∼3.51%), raffinose and sucrose. The content of total free sugar of meju were the highest in Jinpeum among 2.10∼2.66% and composed mainly glucose. The lightness of meju lump in Hwangkeum was larger decrease than the others, the redness were higher in Daeweon and Hwangkeum, the yellowness was the highest in Sodam. The lightness of meju powder was the highest in Sodam, the redness was the lowest in Sodam, the yellowness was the highest in Hwangkeum. The chemical composition of doenjang were that : was the highest in Jinpeum among the 7.90∼9.71% crude lipid, in Daeweon among 9.67∼13.50% crude protein, in Sodam among 2739∼3825 mg% Formol nitrogen and in Daeweon among 6.88∼8.36% crude saponin, respectively. The content of total free sugar of doenjang were the highest in Hwangkeum among 1.88∼2.22% and composed mainly fructose and glucose. The lightness and yellowness of doenjang was the highest in Sodam, the redness was the highest in Hwangkeum. Doenjang by Hwangkeum had good score for taste, texture and overall quality in sensory evaluation.

• Korean journal of applied entomology
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• v.22 no.3 s.56
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• pp.208-212
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• 1983

Sixteen recommended soybean cultivars in Korea were tested for resistance to Heterodera glycines. The nubmer of females which developed on roots of cultivars were fewer on 'Hwanggeum kong' and greater on 'Geumgangdaelib'. But there was no resistant cultivar to Heterodera glycines. Four field populations of Heterodera glycines tested for ability to reproduce on five host differentials. Geographical differentiations of H. glycines were newly founded in Korea. These were identlified to race 1 at Hwasun, race 5 at Yangsan and Suweon and Unknown race(or race C) at Seonsan.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.580-583
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• 2007

Little is known about the genetic variability in lutein content for soybeans (Glycine max L.) cultivated in Korea. Therefore, the objective of this study was to screen high quality soybean cultivars for lutein content. The lutein contents of 23 recommended varieties, 56 sauce varieties, 44 sprout varieties, and 40 local varieties were determined by saponification followed by reversed phase high performance liquid chromatography (HPLC). We found that IT No. 153398 and 22789, originating from sauce and local varieties, respectively, contained significantly higher amounts of lutein as compared to the other 161 samples. Moreover, relevant quantitative differences were found among the samples, which had lutein contents ranging from 83 to $402{\mu}g/100g$ in the recommended varieties, from 39 to $778{\mu}g/100g$ in the sauce varieties, from 52 to $589{\mu}g/100g$ in the sprout varieties, and from 106 to $861{\mu}g/100 g$ in the local varieties, respectively. In summary, this study provides reliable lutein data for soybean cultivars that can be used for breeding studies and the development of functional foods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.347-352
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• 2013

Soybean sprout is a year-round traditional vegetable that is easily produced and relatively inexpensive in Korea. In addition, the sprout is known as a good source of protein, vitamins and minerals. The quality of the soybean sprout has been mainly evaluated only by its appearance like length, width, color, and the others without considering any odor or taste attributes. We studied the chemical factors affecting taste of soy sprouts cultivated with 5 recommended soybean cultivars through evaluation of chemical constituents in relation to their sensory characteristics. Correlation coefficient among the chemical constituents and sensory characteristics of soybean sprout showed that the linolenic acid and Ca contents were positively correlated with total acceptability of soybean sprout and histidine, aspartic acid, and serine showed a negative association with beany odor of soybean sprout. Multiple regression analysis was done to formulate selection criteria for good taste of soy sprout. The estimation of step-wise regression analysis conducted by 47 chemical components for major quality-related characteristics showed that linolenic acid and mineral contents were the main components increasing the acceptability of soybean sprout.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.1
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• pp.26-39
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• 2013

Yield reduction in major cereal grains seems unavoidable with the existing cropping systems under the projected climate change in Korea. Crop models were used to predict the effects of planting date shift on grain yields of rice, winter barley and soybeans at 64 agroclimatic zones in Korea. The shift of planting date by 7, 14, and 21 days before and after the recommended planting dates were incorporated in DSSAT experiment files to simulate growth, development and grain yields of major cereal crops. These included 3 rice cultivars representing early-, medium- and late-maturity groups, 1 winter barley and 1 soybean cultivars. Partial mitigation in yield reduction was found with earlier planting in the early maturing rice cultivar and with delayed planting in the late maturing rice cultivar under the RCP8.5 projected climate change in Korea. Additional yield increase in winter barley was expected by earlier planting treatments. Soybean showed a positive effect on grain yield with earlier planting. However, the rate was much lower than the case with winter barley and delayed planting caused yield reduction.