• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.674-683
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• 2017

The frequency and intensity of soil moisture stress associated with climate change has increasing, and the stability of field crop cultivation has decreasing. This experiment was conducted to investigate the effect of soil moisture management method on growth and yield of corn. Soil moisture was managed at the grade of WSM (wet soil moisture, 34.0~42.9%), OSM (optimum soil moisture, 27.8~34.0%), DSM (dry soil moisture, 20.3~27.8%), and ESM (extreme dry moisture, 16.6~20.3%) during V8 (8th leaf stage)-VT (tasseling stage). After VT, irrigation was limited. The treated amount of irrigation was 54.1, 47.7, 44.0 and 34.5% of total water requirement, respectively. The potential evapotranspiration during the growing period was $3.29mm\;day^{-1}$, and upward movement of soil water was estimated by the AFKAE 0.5 model in the order of ESM, DSM, OSM, and WSM. We could confirm this phenomenon from actual observations. There was no significant difference in leaf characteristics, dry matter, and primary productivity depending on the level of soil moisture, but leaf development was delayed and dry weight decreased in DSM. However, dry weight and individual productivity of DSM increased after irrigation withdrawal compared to that of OSM. In DSM, ear yield and number of kernels per ear decreased, but water use efficiency and harvest index were higher than other treatments. Therefore, it is considered that the soil moisture is concentratedly managed before the V8 period, the V8-VT period is controlled within the range of 100 to 500 kPa (20.3~27.8%), and no additional irrigation is required after the VT.

• Animal Bioscience
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• v.35 no.11
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• pp.1689-1697
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• 2022

Objective: The aim of this study was to compare the effects of three kinds of organic acid (OA) products on the growth performance, intestinal characteristics and morphology, and cecal microflora in broilers fed a corn-soybean meal meal diet. Methods: A total of 420 one-day-old male Cobb 500 broilers with an average initial body weight of 49.11±1.02 g were used in this 42-day experiment. Birds were randomly allotted to one of five treatments (7 replicates with 12 birds per replicate). Treatments consisted of negative control (NC), basal diet; positive control (PC), basal diet+100 mg/kg of Aviramycin; OA1, basal diet+500 mg/kg of OA product 1; OA2, basal diet+1,000 mg/kg of OA product 2; and OA3, basal diet+1,200 mg/kg of OA product 3. Results: The results indicated that OA product addition had no effect on growth performance parameters, such as body weight gain, feed intake, and feed conversion ratio, from days 1 to 14, 15 to 28, and 0 to 42, or on the pH values of the intestine, intestinal weight, or intestinal weight to body weight ratio. The intestinal morphology in terms of villus height and crypt depth were affected by dietary supplementation of OA products, respectively. Furthermore, dietary addition of OAs had positive influences on the maintenance of the cecal microflora based on the results of 16S rRNA analysis. Conclusion: Dietary inclusion of three kinds of OA products all benefit broilers, but the mode of action may be different. This study provides a basis for the application of OA products used in the poultry industry.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.163-170
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• 2022

This study investigates the effects of the dietary inclusion of zinc oxide (ZnO) on the growth performance, apparent total digestibility, and the fecal scores of growing pigs fed a corn-wheat-based diet. In total, 84 crossbred (Landrace × Yorkshire × Duroc) growing pigs with an initial body weight of (20.86 ± 0.64 kg) (4 pigs·pen^-1; 2 gilts and 2 barrows; 7 replications·treatment^-1) were randomly assigned to three treatment groups based on body weight (BW) and sex in a three-week trial. The dietary treatments were as follows: TRT1 (CON [basal diet]), TRT2 (CON + 0.07% ZnO), and TRT3 (CON + 1% ZnO). Dietary ZnO supplementation significantly (p < 0.05) improved body weight gain (BWG) of growing pigs at weeks 2 and 3 compared to the control diet. In addition, dietary ZnO supplementation significantly (p < 0.05) increased the average daily gain (ADG) and average daily feed intake (ADFI) at weeks 2, 3, and overall. However, the feed conversion ratio (FCR) remained unaffected throughout the trial. Regarding the total tract nutrient digestibility of nitrogen, dry matter was significantly improved with an increased level of ZnO supplementation. In addition, dietary supplementation of ZnO significantly reduced fecal scores in grower pigs at the initial period compared to the control diet. In summary, dietary inclusion of zinc oxide via supplementation improved growth performance, and total tract digestibility and reduced the fecal scores of growing pigs.

• Research in Plant Disease
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• v.29 no.2
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• pp.137-144
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• 2023

Exserohilum turcicum is a fungus that causes northern corn leaf blight (NCLB) and has deleterious effects on maize production globally. Therefore, it is prudent to mitigate the effects of NCLB using genetic diversity. The objective of this research was to assess the severity of NCLB disease on the growth and yield of various maize genotypes. A randomized complete block design field experiment, replicated three times, was conducted to evaluate the effect of E. turcicum on 10 maize hybrids. Percent disease index, plant height, and leaf area were recorded at the silk stage. Cob weight, grain fresh weight, and grain yields were determined at harvest maturity. All measured parameters were significantly different (P<0.05) between the maize hybrids. Of the 10 genotypes, four (PAN 4R-528R, PAN 4R-728BR, PAN 3R-724BR, and P1788BR) were susceptible, five (DKC74-74BR, PAN 5R-582R, PAN 5R-890R, PAN 5R-854R, and PAN 5R-590R) were moderately susceptible, and one (DKC80-40BR) was moderately resistant. DKC80-40BR exhibited greater cob weight, while DKC74-74BR was superior in all other plant growth and yield components. Interestingly, although not significant (P>0.05) and high, maize growth and yield parameters had negative correlations with disease incidence, except for grain fresh weight. Therefore, DKC80-40BR may be selected for cultivation in areas prone to NCLB to reduce maize susceptibility to the disease, while DKC74-74BR may improve crop performance. These hybrids could be considered as potential sources of resistance or tolerance to NCLB for further validation by plant breeders.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.639-646
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• 2022

The present experiment was conducted to assess the effect of Buttiauxella-derived phytase in finishing pigs fed corn/soybean meal diets with an increase in the calcium (Ca)/total phosphorus (P) (Ca/tP) ratio and a reduction in net energy on the growth performance and nutrient digestibility on the finishing pigs. A total of 90 crossbred ([Yorkshire × Landrace] × Duroc) finishing pigs with an average initial body weight (BW) of 56.94 ± 2.43 kg were used for an 11-week feeding trial. The pigs were randomly allotted to one of three dietary treatments (six replication/treatment and five pigs/pen) in a randomized complete block design according to their BW and gender. Dietary treatments consisted of supplementation of phytase (0.05, 0.07, and 0.1% in the control, Trt1 and Trt 2 diets, respectively) maintaining the Ca/tP ratio (1.67 : 1, 1.84 : 1, and 2.19 : 1 in control, Trt1 and Trt 2 diets, respectively) and reducing the net energy by 1% in Trt1 and Trt2 diets compared with the control diet. The results showed that dietary supplementation with phytase in the energy-reduced diet had a similar (p > 0.05) effect on the BW, average daily gain, average daily feed intake, and gain/feed ratio of the finishing pigs. Also, there were no effects (p > 0.05) of treatment matrixes on the nutrient digestibility of dry matter, nitrogen calcium, phosphorus, and gross energy. In conclusion, the increase of phytase and Ca/tP ratio and the reduction of net energy in the corn/soybean meal diet resulted in comparable growth performance and nutrient digestibility of finishing pigs relative to pigs fed the control diet.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 1999.02a
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• pp.43-46
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• 1999

The microstructure of Top Seed Milt-Processed $YBa_{2}$$Cu_{3}$$O_{7-\delta}$ single crystal was studied. It was presumed that the segregation of Y211 is due to the difference of growth rates between a, b axis and c axis in crystal direction. Corn kernel lide structure which was grown by the diffusion of Y211 was observed. At the near corner of the seed crystal, the diagonal line on Y123 cry crystal is formed by the corn kernel like structure.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.102-105
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• 2001

Gypsum has been known as a prominent material for improving alkali soil, and this material can be supplied easily in large scale by recycling waste gypsum plasterboard from construction and demolition sites in advanced countries. In April 2000, in the part of western Jilin Province in China, where alkali soil spread vastly, we conducted a cultivating experiment of corn and rice after treating with granule recycled waste gypsum at six alkali soil fields which total area were 14000$m^2$. We confirmed that pH of soil decreased in a short period and alkali soil changed soft a desirable condition for farm work, and furthermore, gypsum caused to accelerate the growth of a plant, both corn and rice.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1519-1522
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• 2009

This study reports the use of different inducing agents (olive, soybean, and used frying oils) and culture mediums [synthetic medium (SM), whey protein, and corn steep liqueur (SL)] to optimize the production of lipase by Fusarium oxysporum. A relationship among the inoculum size, presence of a fat source, fungal growth, and lipase production was evident during the fermentation. The best results were achieved when the inoculum was grown in SM or SL and the fermentation was developed in SM with frying oil as the inducing agent. The maximum activity (about 15 U/mL) was obtained after a 72 hr cultivation.

• Journal of Mushroom
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• v.6 no.1
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• pp.20-26
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• 2008

The stromatal forms of T. fuciformis and the mycelia of Hypoxylon sp. were collected. The DNA sequence in the ITS region of the 5.8S ribosomal genes of isolated strain KG103 was very similar to that of T. fuciformis AF042409 with a homology of over 98% in the EMBL/GenBank database through BLAST searching. A second isolate, No KG201, one of the symbiotic strains for cultivating T. fuciformis also exhibited high homology with Annulohhypoxylon stygium AJ390406. Potato Dextrose Medium exhibited the best mycelial growth of 14 mm/14 days and 85 mm/14 days for T. fuciformis and its symbiotic fungi, respectively. Optimum culture conditions for the micelial growth were pH 5 at $25^{\circ}C$. For the optimization of artificial cultivation of T. fuciformis in bottle with sawdust medium, several conditions such as type of sawdust, supplements, pH, moisture content, and incubation temperature were investigated. T. fuciformis and symbiotic fungi showed fast mycelial growth on corn cob media (77 and 52%) followed by oak tree sawdust and cotton seed meal. The optimal temperature for mycelial growth of T. fuciformis and symbiotic fungi on corn cob media was $25^{\circ}C$ at 55% of moisture content.

• Journal of Animal Science and Technology
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• v.53 no.6
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• pp.533-540
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• 2011

The objectives of experiments were to compare directly the effects of synchrony of slowly fermented (corn and corn gluten meal; C-CGM) and of rapidly fermented ingredients (barley and soybean meal; B-SBM) in the rumen on starch disappearances in gastrointestinal tracts (Experiment 1) and growth performance (Experiment 2) of Hanwoo steers in the feedlot barn. In experiment 1, four Hanwoo steers ($288{\pm}21$ kg) fitted with ruminal and "T" shaped duodenal cannula were placed in one pen with Calan gate and assigned randomly to a duplicate $2{\times}2$ Latin square design. In experiment 2, eight intact Hanwoo steers ($311{\pm}8$ kg) were assigned randomly to one of two pens with Calan gate to evaluate the effect of the same diets as like in experiment 1 on growth performance. There were no differences in ruminal pH, ammonia and total VFA concentrations between treatments. Percentage of apparent ruminal starch disappearance was 33.3% unit lower (p<0.05) for steers fed C-CGM than for steers fed B-SBM diets and this difference resulted in 268% higher (p<0.05) in duodenal starch flows for steers fed C-CGM diet than for steers fed B-SMB diet. There was significant increase (p<0.05) in quantity (927 vs. 400 g/d) of corn starch digested post-ruminally compared to barley starch. However, percentage of starch apparently digested post-ruminally was 8% higher (p=0.1) in steers fed fast synchrony diet with B-SBM than in steers fed slow synchrony diets with C-CGM. The differences of percentage and amount of starch apparently digested post-ruminally between C-CGM and B-SBM diets did not affect rice straw DM intake, average daily gain (ADG) and feed efficiency. In conclusion, there is some uncertainty in regards to the relationship between site of starch digestion and DM intake, ADG, and feed efficiency in this study.