• Asian-Australasian Journal of Animal Sciences
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• v.30 no.5
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• pp.660-665
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• 2017

Objective: The objective of the study was to determine the effects of increasing levels of metabolizable protein (MP) on lactation performance and nitrogen (N) efficiencies in lactating dairy cows. Methods: Nine multiparous cows in mid lactation [$113{\pm}25$ days in milk] received three treatments in a $3{\times}3$ Latin square design with a period length of 21 days. The treatments were three diets, designed to provide similar energy and increasing supply of MP (g/d) (2,371 [low], 2,561 [medium], and 2,711 [high] with corresponding crude protein levels [%]) 15.2, 18.4, and 20.9, respectively. Results: Increasing MP supplies did not modify dry matter intake, however, it increased milk protein, fat, and lactose yield linearly. Similarly, fat corrected milk increased linearly (9.3%) due to an increase in both milk yield (5.2%) and milk fat content (7.8%). No effects were observed on milk protein and lactose contents across the treatments. Milk nitrogen efficiency (MNE) decreased from 0.26 to 0.20; whereas, the metabolic efficiency of MP decreased from 0.70 to 0.60 in low to high MP supplies, respectively. The concentration of blood urea nitrogen (BUN) increased linearly in response to increasing MP supplies. Conclusion: Increasing MP supplies resulted in increased milk protein yield; however, a higher BUN and low MNE indicated an efficient utilization of dietary protein at low MP supplies.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.290-297
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• 2011

The phenology of Campylaephora hypnaeoides J. Agardh and optimal conditions for carpospore release, growth and reproduction were examined in the field and in the laboratory from January to December 2007. In the field population of C. hypnaeoides, approximately 50% of the plants were vegetative during the study period. Additionally, the percentages of carposporophytes and tetrasporophytes were maximal in April (37%) and June (57%), respectively. Maximum growth in plant length, dry weight, and hook number coincided with the tetrasporophyte reproductive peak in the field. In culture, carpospore release, sporeling growth and reproduction were affected by environmental factors such as daylength, temperature, and salinity. The liberation of carpospores was maximum under continuous light and at a combination of $15^{\circ}C$ and $10\;{\mu}mol$ photons $m^{-2}\;s^{-1}$. Maximum growth of tetrasporophyte sporelings occurred at a combination of $20\;{\mu}mol$ photons $m^{-2}\;s^{-1}$ of constant light and $25^{\circ}C$. However, the growth of gametophyte sporelings was maximal under $40\;{\mu}mol$ photons $m^{-2}\;s^{-1}$ of constant light and in a combination of $20^{\circ}C$ and 35 psu. The tetrasporophyte sporelings were grew faster than gametophytes, indicating that gametophyte- and tetrasporophyte-sporelings have different physiological responses to irradiance and temperature. Tetrasporangial branches and cystocarps of C. hypnaeoides were produced from carpospores and tetraspores within 1 month, and they were stimulated at high temperature and irradiance levels. In conclusion, C. hypnaeoides should be seeded using carpospores during early winter (November-December) because cystocarps are easily identified by fishermen, and tetrasporophytes grow faster than gametophytes.

• Journal of Bio-Environment Control
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• v.13 no.3
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• pp.156-161
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• 2004

This study was conducted to investigate the effects of soil amendment with different characteristics on plant growth, fruit yield and quality of oriental melon for continuous cropping under protected cultivation. Humus layers in arable soil was disturbed because soil amendment from hillside to oriental melon field was continued to resolve problems for continuous cropping. Water potential and hardness of soil was decreased in sandy loam with lower clay contents compared with loam and silty clay. Leaf length and area, fresh and dry weight of plant at earlier growing stage were higher, but chlorophyll contents of leaves were dropped in sandy loam compared with silty clay soil. Fruit size and weight was higher in sandy loam, but soluble solid and color of fruit were increased in silty clay. Marketable and unmarketable yield and quantity of fermented fruit were the highest in sandy loam. Hardness and weight of fruit were decreased by longer storage period and soluble solids of fruit was peaked at 5 day after storage, but decreased by prolonged continued storage. Because of these results, soil characteristics of amendment to oriental melon field should be considered as an important factor for quality and yield of oriental melon.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.239-243
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• 2006

Orostachys japonicus, a monocarpic plant, is artificially grown in greenhouses. The study was carried out to examine the effect of shading (0, 35, 55, 75, 95%) on growth, morphological characters, and flowering. The treatments were done on August 25 and afterward samples were taken every 2 weeks until October 20, in which growth, morphological and flowering related characters were measured. With severer shading plant height, inflorescence length, number of leaves including bracts and stem diameter were decreased although severely declined in 95% shading treatment. Leaves and bracts, stem, root, shoot and total dry weights increasingly declined with severer shading. Florets formed on the inflorescence showed similar response to the shading treatment as plant height did. Flowering of the florets was not observed throughout all the sampling period, meaning that different light intensities by shading did not affect their flowering.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.3
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• pp.245-250
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• 2015

This study was conducted from October 2014 to May 2015 to explore forage production and feed values of Italian ryegrass, Rye and whole crop barley as winter forage crops in the Southern region of Korea. The experimental location was over 10 points for each species and each sampling point area was $1m^2$ (Width: 1 m ${\times}$ Length: 1 m). Air mean temperature and rainfall in the Southern region of Korea during the experimental period was $6.95{\pm}5.75^{\circ}C$ and $70.45{\pm}54.68mm$, respectively. Fresh forage yield of Italian ryegrass, the most cultivated forage in the Southern region of Korea, was $44.4{\pm}7.0ton/ha$. The percentage of dry matter for whole crop barley was $28.9{\pm}7.0%$. Crude protein (CP) was higher in Italian ryegrass ($10.7{\pm}5.3%$) while total digestible nutrient (TDN) had the highest value in whole crop barley. Crude protein was not significantly different by location. However, the neutral detergent fiber (NDF), acid detergent fiber (ADF) and total digestible nutrient value of forage from Jeonbuk province were higher than in forage from Gyeongnam province.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.141-146
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• 2014

The necessity to develop economical and eco-friendly technologies is steadily increasing. Plant growth promoting rhizomicrobial strains PGPR are a group of microorganisms that actively colonize plant roots and increase plant growth and yield. Pot experiments were used to investigate the potential of some rhizobacterial strains to enhance the Brassica rapa growth. Microbial strains were successfully isolated from the rhizosphere of Panax ginseng and characterized based on its morphological and plant growth promotion characters. Surface disinfected seeds of Wisconsin Fast B. rapa were inoculated with the selected PGPR microorganisms. The different pots treatments were inoculated by its corresponding PGPR ($10^7cfu\;mL^{-1}$) and incubated in the growth chamber at $25^{\circ}C$ and 65% RH, the light period was adjusted to 24 hours (day). NPK chemical fertilizer and trade product (EMRO, USA) of effective microorganisms as well as un-inoculated control were used for comparison. Plants harvested in 40 days were found to have significant increase in leaf chlorophyll units and plant height and also in dry weight of root and shoot in the inoculated seedlings. Root and shoot length and also leaf surface area significantly were increased by bacterial inoculation in sterile soil. The study suggests that Rhodobacter capsulatus and Azotobacter chroococcum are beneficial for B. rapa growth as they enhance growth and induced IAA production and phosphorus solubilization. This study presents some rhizomicrobial strains that significantly promoted growth of Wisconsin Fast Plant B. rapa in pot experiment under different soil conditions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.3
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• pp.1-9
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• 2016

The objective of this study was to exam early stages of plant growth of Euonymus fortunei 'Emerald and Gold' and Hedera japonica grown in fabric felt bag attached on vertical greenery system with the ratio of hydrophilic polymer to substrate, 0(referred as Control), 0.1, 0.2, or 0.4% (v/v), in order to effectively utilize rainfall for low maintenance. After rainfall, the increase in volumetric water content of substrate amended with the hydrophilic polymer was between 13% and 87%, compared to that in Control. During drought period, higher ratio of hydrophilic polymer to substrate slowly decreased the volumetric water content, and increased plant height, leaf length, leaf width, number of leaves, branch number, and stem diameter of both Euonymus fortunei 'Emerald and Gold' and Hedera japonica with the highest fresh and dry weights of shoots or roots under the 0.1% ratio of hydrophilic polymer.

• Journal of Forest and Environmental Science
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• v.38 no.1
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• pp.38-47
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• 2022

Hymenodictyon orixensis (Roxb.) Mabberley (locally known as Bhutum in Bangladesh) is both an ecologically and economically valuable multipurpose tree species for afforestation and reforestation programs in Bangladesh. Seed germination and seedling development study of H. orixense were conducted to find out the response to different growing medium, e.g., polybag (15×10 cm (T₀) and 20×15 cm (T₁)), sand medium in propagator house (T₂), conventional nursery bed (T₃), and root trainer (T₄) in the Nursery. Consequently, germination behavior and seedling morphological parameters of H. orixense were assessed. The results revealed that the sand medium of the propagator house (T₂) provided the highest germination % (58.57±22.30) and the highest germination energy (11.43±2.43) followed by seedlings growing in 20×15 cm polybags (T1) containing forest topsoil and cow-dung at a ratio of 3:1. Except for germination energy, germination values, and germination capacity, other seed biology parameters, particularly imbibition, germination period, germination rate, and plant survival percent in T₁, T₂, T₃, and T₄ were significantly (p<0.05) different from T₀. Each phenotypic parameter of seedlings and dry matter of shoot and root significantly differed from control except root length (p<0.992). Based on this study, Polybags of 20×15 cm size are regarded as the best medium for quality seedling development of H. orixense. The nursery bed (T₃) had the lowest germination performance and developed more inferior quality seedlings. Thereby, 20×15 cm size of polybags with conventional soil and cow-dung media is recommended for maximum germination and to grow the quality seedlings of H. orixense in the Nursery.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.1
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• pp.89-99
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• 2006

The growth and biomass of reeds(Phragmites australis) growing in a subsurface treatment wetland system were investigated from April 2003 to October 2003. Nitrogen(N) and phosphorous(P) concentrations in above-ground(AG) and below-ground(BG) tissues of reeds were examined and the removal rate of N and P by reeds were analyzed. The system, 29 m in length, 9 m in width and 0.65 m in depth, was constructed in June 2001 on a floodplain in the down reach of the Kwangju Stream in Korea in order to purify polluted water of the stream. A bottom layer of 45 cm in depth was filled with crushed granites(15~30 mm in diameter) and a middle layer of 10 cm in depth was filled with pea pebbles(10 mm in diameter). An upper layer of 5 cm contained course sand. Reeds were transplanted on the surface of the system, which were dug out of natural wetlands, and their shoots were trimmed 40 cm in height. The height and density of the shoots averaged 237.7 cm and 244.0 shoot/$m^2$, respectively, when the reeds grew fully. The maximum biomass of AG and BG tissues were 1,964 and 1,577 g/$m^2$, respectively, and the AG : BG ratio of biomass was 1.26. Mean AG and BG dry weights were recorded as 1,355 and 748 g/$m^2$, respectively. The AG and BG tissue concentrations of N averaged 12.37 and 10.01 mg/g, respectively, and those of P 2.37 and 2.03 mg/g, respectively. Inflow to the system averaged 40 $m^3$/day. The concentrations of total nitrogen(T-N) in influent and effluent were 8.4 mg/L and 3.2 mg/L, respectively, and those of total phosphorous(T-P) were 0.73 and 0.38 mg/L, respectively. The total removal of T-N and T-P by the system during the investigation period averaged 140.2 and 9.7 g/$m^2$, respectively, and the total uptake of N and P by the reeds were calculated as 24.39 and 4.73 g/$m^2$, respectively. Average removals of about 17% of N and about 49% of P by reeds were recorded. The N and P concentrations in AG tissues were significantly different among the three zones of the system:near to inflow(St1), in the middle of system(St2), and near to outflow(St3). The N and P concentrations in BG tissues were also significantly different among St1, St2 and St3. N and P concentrations in AG and BG tissues of reeds growing in St1 were higher than those in St2 and St3. The height and density of shoots of reeds in St1 were larger than those in St2 and St3. Significant amounts of N and P in the influent were taken up by reeds in St1.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.19-27
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• 2018

To study the effect of natural anti-microbial chemicals on the growth and quality of chili peppers, chitosan ($100mg/L^{-1}$), stevia ($250mg/L^{-1}$), and the mixture of both chemicals at the same concentration were sprayed after planting at 1-week interval throughout the experimental period. Plant height was measured twice after the $3^{rd}$ and $4^{th}$ applications. Plant height was numerically reduced in all chemical treatments compared to that of untreated control; however, there was no statistical difference between treatments. The fruit quality was examined at commercial maturity, and only minor differences were found in fruit color, length, and dry matter content between the treatments. Although a statistical difference was not present for soluble sugars levels, total phenolics, and capsaicin contents, yield in all chemical treatments significantly increased compared to untreated control. The effect on yield increase was greater at the late harvest season regardless of treatments. Total yield of 4 harvests was higher for the chitosan treatment than other treatments. During the experiment, the entire experimental field was waterlogged for 1 day due to sudden heavy rainfall, which resulted in the occurrence of bacterial browning disease in all treatments. The rate of disease occurrence and the degree of severity, however, were much lower in the chitosan treatment. In conclusion, the potential of chitosan as an alternative antimicrobial agent was confirmed in chili peppers in this study. Further research is required on stevia as an alternative chemical for disease control in chili peppers.