• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.223-235
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• 2006

Soil testing laboratories unfamiliar with turfgrasses will often overestimate the plant's need for phosphorus and underestimate the need for potassium. This is partly due to differences in rooting between grasses and many garden plants and crops. The grasses are generally more efficient in extracting phosphorus from the soil, reducing their need for phosphorus fertilizer. The fact that crop yield is often the primary objective in field crop production, and is usually of little interest in turfgrass management, may affect soil test interpretation for potassium. Potassium levels above those required for maximum tissue yield of grasses may improve stress tolerance and turfgrasses will usually benefit from higher applications of this element. There are also diffrrences in soil testing philosophies. Some laboratories use the sufficiency level of available nutrients(SLAN) approach, whereas others prefer the basic cation saturation ratio(BCSR) approach. Some will use a combination of the two methods. The use of the BCSR theory easily lends itself to abuse and questionable fertilizer applications and products are sometimes recommended citing imbalances in cation ratios. The usefulness of the BCSR ratio theory of soil testing varies with soil texture and interpretations on tests performed on sand-based media are particularly a problem. Other soil testing problems occur when sand-based media used on sports fields and golf greens contain free calcium carbonate. The ammonium acetate extractant at pH 7.0 dissolves excessive amounts of calcium that can bias cation exchange capacity measurements and measurements of cation ratios. Adjusting the pH of the extractant to 8.1 can improve the accuracy of the testing procedure for calcareous media.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.721-726
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• 2021

Plant cells have a totipotencial capacity, the ability of each cell to produce a new complete individual through development. By applying this, several technologies are being developed for widespread application of somatic embryogenesis by processing hormones in vitro as a method of propagation of plants. In order to use this technology, in Kalanchoe pinnata, a plant capable of asexual reproduction with more regular cell division, kinetin belonging to cytokinin and picloram among hormones belonging to auxin were added in combination and treated for 8 weeks, and then the typical performance was evaluated. As a result of our experiment, the rooting effect in leaf slices showed a 70% incidence rate at a picloram concentration of 0.1 mg/L. It has been proven that a concentration difference of 1:5-1:10 in the ratio of kinetin and picloram is effective. It is the experimental result that the effect of auxin is essential for the development of Kalanchoe roots. As for the effect of shooting, the incidence rate was 60% at the picloram concentration of 0.5 mg/L. The kinetin concentration from 0.5 and 1.0 mg/L and has a significant effect on development. It has been proven that the ratio of kinetin to picloram is effective with a concentration difference of 1:1-1:2. These results show that the combination of cytokinin and auxin is crucially important for shooting. It is thought that it can be the basis of a technology for inducing mass proliferation in vitro by inducing direct organogenesis with a combination of hormones.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.119-125
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• 1996

To improve the efficiency of mass propagation in vitro of Fritillaria thunbergii, bulb scale and nodes were cultured in LS medium supplemented with the combination of 2, 4-D and kinetin or NAA and BA. The number and size of bulb, the number of adventitious shoot, the ratio of callus formation, rooting, and the effects of light and dark on the culture, plant regeneration from calli, and the gelling substances were investigated. The combination of 2, 4-D and kinetin in media was more effective than the media of NAA and BA for the bulblet formation. The media supplemented with 2 mg/L 2, 4-D and 1 mg/L kinetin, $1{\sim}2\;mg/L$ 2, 4-D without kinetin and $1{\sim}3\;mg/L$ BAA only were effective in the adventitious shoot development. Callus formation and root formation, respectively were effective in the medium supplemented with 2mg/L 2, 4-D and 1mg/L kinetin. In bulb formation, the medium with 5 mg/L kinetin was effective, and the most of bulbs were formed from the axillary bud of node part. In bulb formation, shoot growth, callus and root formation, the light culture for 16 hours per day was better than that in the dark culture. Bulb was nicely formed in the medium with 0. 2 mg/L 2, 4-D, 1 mg/L kinetin. The medium without hormone was most effective for plant regeneration. The phytagel was more effective than agar in the medium as the gelling agent.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.219-227
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• 1993

Broadcast-seeded rice in submerged paddy frequently lodge in the field. In general, the causes of lodging in rice cultivation differ with different cultural methods. This study was conducted to investigate the causes of lodging in broadcast-seeded rice (BSR) and hand-transplanted rice (HTR) under four nitrogen (N) levels. Lodging in BSR was mainly a root lodging due to shallow root distribution, while that in HTR showed a bending type owing to deep rooting system. At the upper soil layer (0-5cm from the surface of ground) the root distribution of BSR (65.2%) was much larger than that of HTR (51.6%), whereas at the 5-10cm soil layer the root distribution of BSR (18.5%) was much smaller than that of HTR (28.0%). The depth of buried culm base was much shallower in BSR (1.2cm) than in HTR (4.0cm). The plant height, fresh weight, lodging index, culm diameter and thickness in HTR were much greater than those in BSR, and the breaking strength of lower internode was similar in the two cultivation methods indicating that HTR would have more lodging causes than BSR. In spite of . the more advantages to lodging resistance in BSR it severely lodged in the field. The main lodging-inducing factors of BSR were the shallow root distribution and shallow depth of buried culm base. Besides these, the higher ratio of gravity center of culm was an important factor. This result suggested that for the fundamental prevention of lodging in BSR, an ideotype of rice plant with ' a deep-rooted behavior ' should be developed.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.125-133
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• 1979

The characteristics of landslides occurred in August 5, 1979 in pyeongchangkun were surveyed and indentified as follows. 1. Deep limestone regions. Distinct differences in soil texture between A1 and B horizon could be observed on soil profile, which is attributed to the clay illuviation. The clay illuvial horizon is supposed to be an important cause of large scale mudflows on middle slopes by the lubricant action of ground water flowing between top soil and subsoil. 2. Shallow limestone regions. Very shallow top soils (less than 50cm) laid on tilted bedrock stratification provide a proper condition of mass soil movement if the top soil is saturated and ground water flows between top soil and bedrock when concentrated heavy rainfalls shower. 3. Granite regions. Weathering granitic bedrock produces very coarse textured top soils which are very cohesionless and have many pores. Therefore, the soil has high infiltration ratio and is easy to be saturated by water and to be detached from the bedrock. The landslides abrase very severely both sides of gully with high potential energy when they flow down. The following methods for landslide prevention can be recommended. 1. The original parts of landslides on top of the gully must be treated by intensive planting of deep rooting species and check dams. 2. Clear-cutting and crop planting on steep slope (more than 25 degrees) should be controlled and prohibited. 3. Establishment of landslide prevention forest should be practised on proper site.

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.1-6
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• 2000

This study was carried out to find the effects of plant growth regulators on callus formation, rooting and shooting from cotyledon explant in oriental me]on. Various combinations of 0.1 mg/L auxins (IAA, NAA) and 0.5, 1.0. 1.5, 2.0 mg/L cytokinins (BA, kinetin, zeatin) were treated to the MS basal medium, respectively. Callus was induced mort effectively as 2,437.0 mg (FW)/explant in MS medium supplemented with 0.1 mg/L NAA and 2.0 mg/L BA, but that was non-embryogenic callus as colored yellow white and broke easily. Root was induced most effectively at a frequency of 98.0% in MS medium supplemented with 0.1 mg/L NAA and 0-5 mg/L kinetin. Shoots formed on cut part of vein at a frequency of 98.0% in MS medium supplemented with 0.1 mg/L IAA and 2.0 mg/L BA, that were multiple shoots. in case of its concentration, BA and lower concentration of IAA and NAA (0.01 and 0.05 mg/L). respectively. shooting ratio was not increased. The result of treatment with BA 0-5 mg/L and IAA 0.1 mg/L, callus induced at a week, and shoot start to form multiple shoots about 3 weeks after inoculation. After 2 times subculture as 2 weeks intervals, divided shoots rooted and developed into intact plantlets at 10 weeks and then that grown normally on pots after acclimatization.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.146-156
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• 1988

This study was carried out to investigate the change of endosperm substance and seedling growth in rice seedlings for machine transplanting with use of two rice varieties, which Samgangbyeo (Indica${\times}$Japonica) and Dogjinbyeo (Japonica) were sown on May 8 with five levels of seeding density. 1. The total dry matter weight, leaf area, length of the longest root, number and length of new roots were negatively correlated with seeding density, and the plant height had the similar tendency to them from 20 days after sowing(DAS). 2. The rooting ability was negatively correlated with seeding density and decreased from 35 DAS in Dongjinbyeo. 3. The endosperm substance were exhausted at 25 to 30 DAS in Samgangbyeo and at 25 DAS in Dongjinbyeo. 4. The leaf area was more useful than the ratio of plant height to dry matter weight for judging the constitution of seedlings. 5. The reducing sugar contents in the endosperm were the greatest among parts of rice seedlings followed by leaf and root. The contents in leaf, root and endosperm reached maximal at 10 DAS, and varied with plant parts, seedling growth and varieties in different levels of seeding density. 6. The protein contents in leaf and root of rice seedlings became decreased with seedling growth., and were minimal values at 15 DAS. The content in endosperm was decreased soon after seeding, and minimal at 4 DAS with showing some fluctuation of protein content after then.

• Horticultural Science & Technology
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• v.17 no.2
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• pp.111-114
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• 1999

Experiments were conducted to select the optimum cultivars which are adaptable to South Korea through estimating the differences in daughter plant production and growth response among seven strawberry cultivars. In the vegetative stage, Nyoho, Akihime and Suhong produced more daughter plants than other cultivars whereas Akaneko and Tochinomine, which developed less runners, showed better condition in runner vigorness. The quality of daughter plants derived from forcing cultivars was uniform in general. Even though there was no significant differences in rooting among cultivars, runners from Akaneko and Tochinomine developed more roots and fresh weight of roots than other cultivars. In the forcing cultivars, Akihime showed the most excellent plant vigorness, yield and highest sugar content of fruits and also was 5 days faster than Nyoho in flowering date. However, the fruit tended to be softened. In the semi-forcing cultivars, Tochinomine was excellent in vigorness, firmness, sugar content of fruits and the average of fruit weight but low in flower numbers per cluster and late in the emergency of second flower cluster. Although Akaneko showed highest in sugar/acid ratio and rich in flavour, lighting treatment was recommended to this cultivar for early harvest because of softness of fruits.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.155-165
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• 2016

Domestic and international production of Tricholoma matsutake has decreased owing to matsutake forests being left alone, host plant disease, forest fires, climate change, and so on. In order to identify strains that are suitable for the production of T. matsutake-inoculated seedlings, Pinus densiflora seedlings were inoculated with T. matsutake after in vitro rooting and mycorrhization was examined in the roots of T. matsutake-inoculated seedlings after 6 months. The mycorrhization rate was greater than 80% for 5 strains (NIFoS 421, 434, 1681, 1984, and 2001) out of 19 total strains. Seven strains (NIFoS 434, 441, 561, 562, 1016, 1807, and 1812) showed shoot/root ratios of less than 3.0 and had a seedling shoot biomass of 2.0 to 4.8 times higher than that of the root. Eight strains (NIFoS 441, 561, 562, 1016, 1807, 1812, 1984, and 2001) stimulated increases in shoot volume and three stains (NIFoS 441, 562, and 1812) promoted the growth of root biomass by mycorrhizal formation. In conclusion, 4 strains (NIFoS 434, 561, 1984, and 2001) out of 19 total strains tested showed higher mycorrhization rates and seedling growth than those of the other strains. We expect that the use of these four strains may contribute to T. matsutake-inoculated seedling production.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.98-111
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• 2015

Urban environmental problems such as flooding, depletion of ground water, pollution of urban streams and the heat island effect caused by urban development and climate change can be mitigated by the improvement of the urban water cycle. For the effective planning of water cycle management it is necessary to establish aerial Hydrotope Maps, with which we can estimate the status and change of the water allowance for any site. The structure of the German water balance model BAGLUVA, which is based on soil and vegetation, was analyzed and the input data and boundary condition of the model was compared with Korean data and research results. The BAGLUVA Model consists of 5 Input categories (climate, land use, topography, soil hydrology and irrigation). The structure and interconnection of these categories are analyzed and new concepts and implementation methods of topographic factor, maximum evapotranspiration ratio, effective rooting depth and Bagrov n parameter was compared and analyzed. The relation of real evapotranspiration ($ET_a$)-maximum evapotranspiration ($ET_{max}$) - precipitation (P) was via Bagrov n factor represented. The aerial and land use oriented Hydrotope Map can help us to investigate the water balance of small catchment areas and to set goals for volume of rainwater management and LID facilities effectively in the city. Further, this map is a useful tool for implementing water resource management within landscape and urban planning.