• Korean Journal of Agricultural and Forest Meteorology
• /
• v.5 no.3
• /
• pp.208-212
• /
• 2003

Extended light illumination by street lamp and automobile light has provoked problem in farmland. Night break was imposed by incandescent lamp (50∼60 lux) for 10 minutes every three hours during 12 hours dark period increased culm length compared to continuous dark of 12 hours, and decreased the number of grains per spike in rice. However, these characters were increased by 12 hours dark period with and without night break as compared to 9 hours continuous dark condition. Compared to 12 hours continuous dark condition, night break delayed heading by 9 and 26 days and 9 hours continuous dark condition delayed it by 47 and 41 days in Ilpumbyeo and Hwaseongbyeo, respectively. Night break increased stem length and node number, while decreased pods of soybean cultivar Hwanggeumkong. The stem length and node number were increased by 9 hours continuous dark condition compared to 12 hours dark condition with and without night break. Compared to 12 hours continuous dark rendition, night break delayed flowering by 4 days and to 9 hours continuous dark condition by 19 days.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.10
• /
• pp.1244-1249
• /
• 2009

Endophytic fungi are known for the production of valuable metabolites, but information on the gibberellin production capacity of this group is limited. We isolated 9 endophytic fungi from the roots of salt-stressed soybean plants and screened them on waito-c rice, in order to identify plant growth promoting fungal strains. The fungal isolate TK-2-4 gave maximum plant length (20.35 cm) promotion in comparison with wild-type Gibberella fujikuroi (19.5 cm). In a separate experiment, bioassay of TK-2-4 promoted plant length and biomass of soybean cultivar Taegwangkong. The TK-2-4 culture filtrate was analyzed for the presence of gibberellins, and it was found that all physiologically active gibberellins, especially $GA_4$ and $GA_7$, were present in higher amounts ($GA_1$, 0.11 ng/ml; $GA_3$, 2.91 ng/ml; $GA_4$, 3.21 ng/ml; and $GA_7$, 1.4 ng/ml) in conjunction with physiologically inactive $GA_9$ (0.05 ng/ml), $GA_{12}$ (0.23 ng/ ml), $GA_{15}$ (0.42 ng/ml), $GA_{19}$ (0.53 ng/ml), and $GA_{20}$ (0.06 ng/ml). The fungal isolate TK-2-4 was later identified as a new strain of Phoma herbarum, through the phylogenetic analysis of 28S rDNA sequence.

• Applied Biological Chemistry
• /
• v.29 no.2
• /
• pp.175-181
• /
• 1986

Eightyseven strains of indigenous Rhizobia were isolated from the nodule of soybean cultivar, Danyup, cultivated in four different soils sampled from continuously soybean cultivated and newly reclaimed fields. The strains were grouped into Bradyrhizobium japanicum (slow-grower:55 strains) and Rhizobium fredii (fast-grower: 32 strains). The both groups could be divided into two sub-groups according to the denitrification characteristics, that is, denitrifying fast-grower (F-I), nitrate respiring fast-grower (F-II), denitrifying slow-grower (S-I). and nitrate respiring slow-grower (S-II). Among the 87 isolates, F-I, F-II, S-I and S-II sub-groups were 10, 22, 48 and 7 strains, respectively. The one-and two-dimensional polyacrylamide gel electrophoretic pattern of the four sub-groups were compared and discernible difference was observed between fast and slow-grower, but the difference was not discernible between subgroups within the same growth rate group.

• Korean journal of applied entomology
• /
• v.23 no.4 s.61
• /
• pp.197-202
• /
• 1984

Two soybean cultivars Hanan and Kwanggyo were used to monitor SMV spread in the field. The Haman producing mosaic symptoms by infection with SMV strain G7 was planted in $2.2m^2$ at the coater of $320.7m^2$ field and Kwanggyo producing necrosis by infection with SMV-G7 was planted around the Haman one day after inoculation of Heman with SMV-G7. The most severe incidence of the necrotic disease in soybean cultivar Kwanggyo occurred on 43 days after planting(July 13) whereas aphid population reached peak around 22 days after planting(June 22). Total incidence of the necrotic disease was $20.4\%$, in the whole field and $56\%$, in eight $mall plots around the spreader of SMV. The spread of S MV outward from the spreader source was greater downwind than it was upwind. Spread also showed a signigicant gradieut pattern leeward from the infection focus.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.spc1
• /
• pp.136-140
• /
• 2005

This study was conducted to determine antioxidative enzyme activity in serum of rats as affected by soybean cultivar, extract feeding concentration and fat dietary. In all cultivars, activities of antioxidant enzymes in treatment of various fat compositions and cholesterol followed by feeding soy-extracts were higher than in nonfeeding control, however, no significant differences existed in statistically. The activities of SOD and GSHpx in serum of rats when fed with various fat dietary were higher in Geomjeongkong 1 than in Tawonkong and Hwangkeumkong. Enzyme activities of SOD and GSHpx with each fat compositions in treatment soy-extracts was no significant differences statistically. There was significant differences among cultivars and concentrations of soy-extracts in interaction effect. Also, the activities of GSHpx was significant differences among cultivars and concentrations of soy-extracts and fat composition in interaction effect.

• Food Science and Biotechnology
• /
• v.15 no.3
• /
• pp.392-398
• /
• 2006

Four flavonoids 1-4 and one phytosterol 5 were isolated from methanol extract of Taekwangkong, one of the soybean cultivars, and the structures of these compounds were fully characterized by physical and spectral analysis. The content of compounds 1-4 as determined by $C_{18}$ reversed phase HPLC (high-performance liquid chromatography) coupled with diode-array detector were 12.1, 624.6, 18.0, and $219.6\;{\mu}g/g$, respectively, and the total phenolic content of this cultivar was measured as 3.7 mg gallic acid equivalent per g dry material (GAB/g). Also, compound 1 showed strong radical scavenging activity in the 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay ($IC_{50}\;=\;47.6\;{\mu}M$), five-fold higher than seen in the 1,1-diphenyl-2-picrylliydrazyl (DPPH) assay. These results lead to the conclusion that soybean not only has many phytoestrogens but also has potent antioxidant activity.

• Korean Journal of Plant Resources
• /
• v.34 no.6
• /
• pp.542-554
• /
• 2021

In this study, we cultivated 115 Soritae and 86 Yakkong black soybean landraces collected from ten different locations in Korea. Then, the variations of three yield components (one-hundred seeds weight (HSW), number of seeds per pod (SPP), and yield per plant (YPP)) and three anthocyanins (cyanidin-3-O-glucoside (C-3-O-G), delphinidin-3-O-glucoside (D-3-O-G) and petunidin-3-O-glucoside (Pt-3-O-G)) were investigated according to landrace type and collection area. Both yield components and anthocyanin contents significantly varied between the soybeans demonstrating genetic differences. Soritae landraces had the highest average HSW and TAC, whereas Yakkong landraces displayed the highest average SPP irrespective of collection area. Relatively, Yakkong landraces from Gyeongsangnam-do (1697.29 mg/100 g) and Soritae landraces from Gyeonggi-do (2340.94 mg/100 g) had the highest average TAC. Principal component analysis clearly separated Soritae and Yakkong landraces. Moreover, TAC and C-3-O-G showed positive and significant associations in both Soritae (r = 0.972) and Yakkong (r = 0.885) landraces, while yield components showed negative or weak correlations with each other. Overall, ten landraces were identified as important resources owing to their high yield (>150 g/plant) and high level of TAC (>2300 mg/100g). This study could lay foundations to molecular level investigations and reinforce the use of Yakkong and Soritae landraces during cultivar development.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.32 no.1
• /
• pp.67-77
• /
• 1987

To obtain basic information concerning the soybean cultivar differences of physiological and ecological responses to soil pH to select and breed stably higher yielding cultivars, and to improve cultural management of soil differing in pH, the responses of soybean plants in growth, grain yield, nodule formation and its activity, and major chemical compositions of soybean plants were investigated using six cultivars and two levels of soil pH 5 and 7 of the pot and field experimental soil in Suwon, 1985. Acidic soil condition suppressed overall vegetative growth of soybean plants and thereby decreased stem length, number of nodes, leaf area, dry weight of the plants, root activity, nodulation and nodule activity, the content of allantoin nitrogen, total nitrogen, phosphorous, calcium, and magnesium of the plants. Due to the such responses of soybean plants to the acid soil, grain yield also decreased along with less grains per plant. However, the little difference in growth and yield of the cultivar Janbaeglcong in response to soil pH is considered to be a good source of breeding materials tolerant to acidic soil condition. In this regard Bongeui and Oialkong also were relatively stable in the growth and grain yield under the different soil acidity conditions.

• Korean Journal of Soil Science and Fertilizer
• /
• v.21 no.3
• /
• pp.307-315
• /
• 1988

This experiment was conducted to find out the effects of fertilizer-N and co-inoculation of the Rhizobium japonicum and the Azospirillum lipoferum on nodulation, $N_2$-fixation, and growth of soybean under in situ conditions. The results obtained were summarized as follows: 1. The yield of soybean dry matter was significantly greater in the R. japonicum alone, and the mixed inoculation of R. japonicum and A. lipoferum than those of un-inoculation. But inoculum applied by different strains did not significant effect on plant growth. The effects of nitrogen applied on soybean dry matter were higher in the ammonium sulfate than potassium nitrate, and decreased with increasing rates of two forms of nitrogen applied regardless of nitrogen source. 2. Acetylene redution activity was more increased in a single inoculation of R. japonicum than those of the mixed inoculation of the R. japonicum and the A. lipoferum, in cases of Danyeup cultivar, regardless of the form of combined nitrogen used. 3. Nodule mass and total nitrogenase activity per plant showed the positively significant effect in the interrelationship between dry matter of soybean and some factors related to nitrogen fixation efficiency. 4. The highest symbiotic effect in Danyeup cultivar was obtained when a single R. japonicum 84 Dy-1 strain was inoculated and fertilized with 18 mM potassium nitrate.

• Korean Journal of Plant Resources
• /
• v.32 no.5
• /
• pp.519-542
• /
• 2019

Twenty soybean cultivars developed recently were assessed using 27 insertion and deletion (InDel) markers derived from dense variation blocks (dVBs) of soybean genome. The objective of this study is to identify the distinctness and genetic relationships among a total of 169 soybean accessions including new cultivars. The genetic homology between 149 accessions in the soybean barcode system and 20 new cultivars was 61.3% on average with the range from 25.9% to 96.3%, demonstrating the versatile application of these markers for cultivars identification. The phylogenic analysis revealed four subgroups related to their usage. The 80% of cultivars for vegetable and early maturity and the 65.9% of cultivars for bean sprouts were clustered in subgroup I-2 and II-2, respectively, indicating of the limited gene pools of their crossing parents in breeding. On the other hands, the cultivars for soy sauce and tofu with considerable gene flow by genome reshuffling were distributed evenly to several subgroups, I-1 (44.4%), I-2 (26.4%) and II-2 (23.6%). We believe that the 27 InDel markers specific to dVBs can be used not only for cultivar identification and genetic diversity, but also in breeding purposes such as introduction of genetic resources and selection of breeding lines with target traits.