• The Plant Pathology Journal
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• v.15 no.1
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• pp.1-7
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• 1999

The production of soybean cyst nematode (SCN), Heterodera glycines, including female formation and fecundity was much higher in SCN race 14 (R14) than in race 3 (R3) in susceptible soybean cultivars Bragg (intolerant), Lee74 (moderately tolerant), and PI 97100 (highly tolerant). The nematode body was also significantly larger in R14 than in R3 at 20 days after inoculation, but the further nematode growth appeared to be slower in R14 than in R3, resulting in no significant difference between the two races at 30 days after inoculation. Within each race, no significant difference was observed in the growth and reproduction among the soybean cultivars tested. Syncytial areas near the nematode lip regions (infection sites) were measured for each soybean cultivar-SCN race combination. R14 induced significantly larger syncytia than R3. Bragg had relatively larger syncytia than Lee74 and PI 97100, but the difference among the soybean cultivars was minimal or not significantly different. Syncytium occupation in the stelar region differed only between PI 97100 and the other two cultivars, which may be somewhat, but not exactly, related to tolerance levels. Syncytial cytomplasm was degenerated more with R14 and in Bragg than with R3 and in Lee74 and PI 97100, respectively. In light microscopy, degenerated syncytia were characterized by depleted and loose cytoplasm with less plastids than normal-looking (intact) syncytia which had dense syncytial cytoplasm. Electron microscopy revealed that degenerated syncytia contained highly vacuolated cytoplasm with degenerated plastids. The above results suggest that structural characteristics of syncytia may match the nematode growth and reproduction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.254-260
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• 1982

Ten soybean varieties were cultivated to know the varietal differences of lodging patterns of soybean plants under three different plant populations in two growing seasons in 1981. Lodging plant percentage was increased in higher plant populations and lodging responses to plant populations were different between soybean varieties. Lodging plant percentage was also increased by the growth of soybean plant and the patterns of lodging development along with the growth stages could be classified into four types by the varieties used, relatively lwoer iodging plant percentage from early to later growth stage but high in late and relatively high in middle stage but low in later stage. Williams, indeterminate type, and Kang-lim, determinate type, showed resistance to lodging under six different cultural practices, but Jang-yeop-kong, Dan-yeop-kong and Hwang-keum-kong showed resistance to lodging under specific cultural conditions among ten varieties used. Most of the plants lodged showed main stem bending in parts above first stem node in higher plant population and lodging resistant varieties showed lower frequency of stem bending lodging compared with those of lodging susceptible varieties.

• The Plant Pathology Journal
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• v.39 no.5
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• pp.513-521
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• 2023

Seed-borne diseases reduce not only the seed germination and seedling growth but also seed quality, resulting in the significant yield loss in crop production. Plant seed harbors diverse microbes termed endophytes other than pathogens inside it. However, their roles and application to agricultures were rarely understood and explored to date. Recently, we had isolated from soybean seeds culturable endophytes exhibiting in-vitro antagonistic activities against common bacterial and fungal seed-borne pathogens. In this study, we evaluated effects of seed treatment with endophytes on plant growth and protection against the common seed-borne pathogens: four fungal pathogens (Cercospora sojina, C. kikuchii, Septoria glycines, Diaporthe eres) and two bacterial pathogens (Xanthomonas axonopodis pv. glycines, Pseudomonas syringae pv. tabaci). Our experiments showed that treatment of soybean seeds with seed endophytes clearly offer protection against seed-borne pathogens. We also found that some of the endophytes promote plant growth in addition to the disease suppression. Taken together, our results demonstrate agricultural potential of seed endophytes in crop protection.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.181-187
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• 2014

Polycyclic aromatic hydrocarbons (PAHs) are a group of ubiquitous hazardous pollutants derived from fossil fuel, various combustion sources and pyrolysis of a wide range of plastics. Because PAHs can be uptake into crop plants, the inhibitory effects on rice and soybean plants were examined in greenhouse and growth chamber experiment. Soil-applied PAHs (phenanthrene of 0, 10, 30, 100 ppm) slightly reduced the plant height and dry weight both in transplanted rice and soybean plant. The inhibitory effect on growth was greater in soybean than rice. Plant height of soybean plants treated by 100 ppm was 58.9 cm and this value was 87.2% of untreated plant. In rice plant, the plant height was less inhibited (96.0% of untreated plant) by 100 ppm at 80 days after treatment (DAT). However, leaf chlorophyll content and chlorophyll fluorescence were less inhibited by PAHs at late growth stage (after heading) although the photosynthesis-related parameters were slightly inhibited from 20 DAT to 70 DAT. In agar medium experiment with infant seedlings, inhibition of seedling length and fresh weight by phenanthrene at 100 ppm were greater as compared to the experiment with adult plant in pot. Seedling length and fresh weight were reduced by 54.2% and 33.3% for rice and 27.9% and 13.2% for soybean, respectively. The results reflected that PAHs were more inhibitory during juvenile stage than adult stage and more inhibitory to rice plant than soybean for juvenile stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.14-18
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• 2010

This study was conducted to investigate the effect of high-temperature during the reproductive growth period on the soybean growth and yield. Two soybean cultivars, Hwangkeumkong (HKK) and Pungsannamulkong (PSNK) were used in this study. By high-temperature treatment, plant height was increased in the two soybean cultivars, however, leaf area and dry weight were greatly reduced. Number of pod per plant was not changed by high-temperature treatment. However, number of seeds and 100 seed weight were reduced in two soybean cultivars. As compared with control, yield were decreased by 45% in both HKK and PSNK. It was also appeared that nitrogen contents in leaf, stem, and root of the HKK and PSNK were decreased by high-temperature treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.145-149
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• 2001

This study was performed to evaluate the growth and nodulation characters of hypernodulating soy-bean mutant, SS2-2, and to know the growth and yield performance of the mutant in infertile soil. Soil fertility was adjusted by mixing the different ratios of soil components including clay, river sand, and horticultural bed, which resulted in fertile and infertile soil. Dry weight, nitrogen concentration, and leaf nitrate reductase of each plant were measured around V6 stage (47 days after planting) and around R3 stage (82 days after planting). There were significant effects of soil fertility and soybean genotype on the total dry weights including root, nodule, stem, leaf, and pod dry weight at V6 and R3 stages. Total dry weight of hypernodulating mutant, SS2-2, was clearly less than that of its wild type, Sinpaldalkong 2. However, nodule development on the roots of SS2-2 was much greater than that of Sinpaldalkong 2, regardless of soil fertility. Though SS2-2 was smaller in plant size than Sinpaldalkong 2, genotypic difference in total nitrogen content was not significant at both V6 and R3 stages because SS2-2 fixed more nitrogen biologically than its wild type in the root nodule. The SS2-2 mutant showed lower plant yield in both infertile and fertile soil. The SS2-2 contained more crude seed protein than Sinpaldalkong 2, and was characterized with reduced top and root growth.

• Korean Journal of Agricultural Science
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• v.51 no.2
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• pp.179-186
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• 2024

Soybean meal (SBM) is a high-protein plant product commonly used as the primary protein source in pig diets. However, its price has been steadily rising, prompting us to search for cost-effective, high-yield protein sources. This experiment aimed to assess the effects of partial replacing SBM with 6% of palm kernel meal (PKM), lupin kernel (LK), rapeseed meal (RSM), and distillers dried grains solubles (DDGS) on the growth performance, nutrient digestibility, and fecal scoring in growing pigs. A total of 200 (Yorkshire × Duroc) growing pigs with an initial weight of 34.83 ± 1.38 kilograms were utilized in this research for 29 days. All pigs were randomly assigned to one of five dietary treatments based on their gender and initial body weight, Each treatment consisted of 10 replicates with 2 barrows and 2 gilts per pen. The dietary treatments were as follows: control (CON), a corn-SBM-based diet; and basal diet supplemented with 6% of different plant byproducts (PKM, LK, RSM, and DDGS) Adding 6% of RSM to the basal diet showed slightly higher daily gain (2.520 > 2.513) and there was no difference observed on the nutrient digestibilty and fecal score. Replacing soybean meal with different plant byproducts has no adverse effect on growth performance, nutrient digestibility, and fecal score.

• Journal of Plant Biology
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• v.20 no.1
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• pp.15-22
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• 1977

As a basic research for the yield-mechanism of soybean seeldings, the distribution and variety of free amino acid and protein-amino acid in some parts of root were studied. At the meristematic, elongational and maturated zones of root, the distribution and variety of N-components was different substantially. It shows that N-components are taken part in energy source for organization in early stage of growth. N-pool also changed in every part of root.

• The Plant Pathology Journal
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• v.32 no.2
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• pp.112-122
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• 2016

Virus-induced gene silencing (VIGS) is an effective tool for the study of soybean gene function. Successful VIGS depends on the interaction between virus spread and plant growth, which can be influenced by environmental conditions. Recently, we developed a new VIGS system derived from the Soybean yellow common mosaic virus (SYCMV). Here, we investigated several environmental and developmental factors to improve the efficiency of a SYCMV-based VIGS system to optimize the functional analysis of the soybean. Following SYCMV: Glycine max-phytoene desaturase (GmPDS) infiltration, we investigated the effect of photoperiod, inoculation time, concentration of Agrobacterium inoculm, and growth temperature on VIGS efficiency. In addition, the relative expression of GmPDS between non-silenced and silenced plants was measured by qRT-PCR. We found that gene silencing efficiency was highest at a photoperiod of 16/8 h (light/dark) at a growth temperature of approximately $27^{\circ}C$ following syringe infiltration to unrolled unifoliolate leaves in cotyledon stage with a final SYCMV:GmPDS optimal density $(OD)_{600}$ of 2.0. Using this optimized protocol, we achieved high efficiency of GmPDS-silencing in various soybean germplasms including cultivated and wild soybeans. We also confirmed that VIGS occurred in the entire plant, including the root, stem, leaves, and flowers, and could transmit GmPDS to other soybean germplasms via mechanical inoculation. This optimized protocol using a SYCMV-based VIGS system in the soybean should provide a fast and effective method to elucidate gene functions and for use in large-scale screening experiments.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.22-31
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• 2005

To evaluate growth adaptation of the soybean in paddy field, five soybean cultivars were grown in Yeoncheon with two cultivating methods, level row and high ridge. Growth characters of the top plants, such as stem lengths, numbers of branches, diameters of stem, were higher under high ridge than under level row. However, the differences among the cultivars were bigger than those between the cultivation methods in each cultivar. Comparing the growth of top plants, dry matters in level row were higher than those in high ridge in V5 stage, however, via verses as growth progressed with significant differences among the cultivars. Roots were more developed under high ridge than those under level row during whole growth stages, such as V5, R2, and R5 stages. T/R ratio in level row was significantly higher than that in high ridge with significant differences among the cultivars.