• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.253-263
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• 2016

Chrysanthemum production would benefit from crop growth simulations, which would support decision-making in crop management. Chrysanthemum is a typical short day plant of which floral initiation and development is sensitive to photoperiod. We developed a model to predict phenological development and leaf appearance of chrysanthemum (cv. Baekseon) using daylength (including civil twilight period), air temperature, and management options like light interruption and ethylene treatment as predictor variables. Chrysanthemum development stage (DVS) was divided into juvenile (DVS=1.0), juvenile to budding (DVS=1.33), and budding to flowering (DVS=2.0) phases for which different strategies and variables were used to predict the development toward the end of each phenophase. The juvenile phase was assumed to be completed at a certain leaf number which was estimated as 15.5 and increased by ethylene application to the mother plant before cutting and the transplanted plant after cutting. After juvenile phase, development rate (DVR) before budding and flowering were calculated from temperature and day length response functions, and budding and flowering were completed when the integrated DVR reached 1.33 and 2.0, respectively. In addition the model assumed that leaf appearance terminates just before budding. This model predicted budding date, flowering date, and leaf appearance with acceptable accuracy and precision not only for the calibration data set but also for the validation data set which are independent of the calibration data set.

• Asian Journal of Turfgrass Science
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• v.6 no.1
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• pp.29-37
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• 1992

This experiment was carried out in order to study the changes of morphological characters of the growth and thatch accumulation in :3 varieties of Kentucky bluegrass under removing clipping residues as affected by cutting management. The varieties used were Park, Kenhiuc and Newport.The results obtained are as follows; 1. The dry weight of leaf. stem and number of tiller was highest at 22. June and lowest at 21. Aug in alt varieties. And then the dry weight of rhizome, root and thatch increased with growth progressed) Tabte 3). 2. The relationship of the dry weight of biological yield and number of tillers was quadratic ally increased in the growth stage of spring($R^2$= 0.982**), and linearlly increased in the growth stage of autumn(r 0.944*)(Fig. 1). :3. The dry weight of thatch increased as an exponentially equation in alt :3 varieties of Kentucky blue-grass(Fig. 2). Thatch increased rate(TIR) can used to estimate the specifying a quantity of thatch accumulation from the turf. Thatch increase rate equation as follows. where TH$_2$ is the dry weightof thatch at T$_2$ survey time and TH$_1$ is the dry weight of thatch at $TH_1$ is the dry weight of thatch at $T_1$ survey time. $TIR(mg/cm^2/day)=\frac{Ln\;TH_2 - Ln\; TH_1}{T_2 - T_1}$ 4. Correlation coefficients between the dry weight of thatch and leaf weight was -0.633(P>0.05), and number of tiller of tillers was -0.666(P>0.5), respectively. It means that thatch accumu-lation increased with growth depression of leaf and stem.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.72-77
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• 1982

To develop a new propagation method of Korean ginseng (Panax ginseng C.A. Meyer) by cutting, stem cuttings with leaflets obtained from ginseng seedlings were planted in rooting media treated with three levels of NAA concentration. NAA solution of 1.0 ppm was the most effective for the rooting of ginseng stem cuttings as well as for root growth after initiation of the roots from cuttings. A mixture of sand and leaf compost as a rooting medium for ginseng stem cuttings showed the best results in rooting percentage of cuttings and root growth after rooting. An acril film cap covering was very effective to prevent water loss by transpiration from the leaflets of stem cuttings and for rooting and root growth after rooting. Cuttings of leaf petiole with 5 leaflets from 2 year old ginseng plants showed good rooting as well as root growth after rooting in a mixture of sand and leaf compost treated with 1.0 ppm NAA.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.201-206
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• 1999

For the mass production of plug seedlings in cultivar ‘Dejima’ potato (Solanum tuberosum L.) the optimal apical cutting diameter for rooting and rapid multiplication of stem cuttings in hydroponics were determined. In addition, the best planting date was predicted to increase tuber yield of plug seedlings at fall cropping in Cheju-Do, Korea. Days to initial rooting decreased as the cutting diameter was reduced. Plant height, leaf number, root length and root weight per plant were favorable as the cutting diameter was small. The ideal cutting diameter was 1-2 mm in this experiment. In the hydroponic cultures, the Japanese standard (JS) nutrient solution was the most effective for multiplication of stem cuttings. It was able to propagate more than 20 times a month from a single mother plant. Viability of plants, which were derived from plug seedlings using stem cuttings, was excellent when transplanted to the field. The number of tubers and tuber yield in both of the plug seedlings and seed potato planting plots were high when planted on 25 August. The number and yield were reduced when planted on 15 August, 5 September and 15 September. The degree of decrease of tuber yield in the plug seedling planting plot however, was lower than that of seed potatoes when the planting date was late. In the case of small tubers (under 30 g), the number of tubers and tuber yield were evidently increased in the seed potato tuber planting plot; the yield of large tuber (over 80g) in the plug seedling planting plot was higher than that of the seed potato. The total tuber yield per plant in the plug seedling planting plot was less than that of the seed potato; therefore, in order to increase tuber yield it was necessary to increase field plant density.

• Journal of Korean Society of Forest Science
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• v.76 no.3
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• pp.218-229
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• 1987

This study was carried out to investigate all the parts' weight growth under the different light intensity and root-cutting. As results : ${\cdot}$ Fresh and dry weight of leaf, shoot, root and seedling treated under 63% R.L.I showed the largest growth. ${\cdot}$ The largest growth in fresh and dry weight of shoot arid seedling appeared at 1/4 root cutting plot. ${\cdot}$ The value of T/R ratio was increased in low light intensity and high root-cutting. ${\cdot}$ The simple nonlinear relationship between light intensity, root-cutting and T/R ratio was recognized, respectively.

• Journal of Life Science
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• v.8 no.5
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• pp.492-496
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• 1998

Intact measurement of leaf water content was attempted using the transmission of beta radiation. Prior to the experiments, two tested plants, rice and soybean, were grown in 1/5000a wagner pot. The moisure ratio of plant leaves were measured with the beta radiation transmission method using a G-M detector and $^{99}$ Tc as the beta ray sou-rce. Beta radiation transmission showed a tendancy to increase with the passage of time after leaf cutting. However, it showed a tendancy to decrease with water supply for the lack of water. A positive correlation was found between the leaf water content and beta radiation transmission. The mutiple regression analysis about leaf water content was obtained that the coefficient of partial regression for beta radiation transmission was much higher(rice; -0.863, soybean; -0.904) than that for specific leaf area(rice; 0.007, soybean: 0.004).

• Journal of agriculture & life science
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• v.44 no.3
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• pp.23-30
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• 2010

The optimal growth condition of in vitro stem cutting of Dendrobium nobile 'Hamana Lake Dream' ${\times}$ 'No. 55' was investigated. Among various media and their concentrations, MS media had better effect on the growth of micro stem cutting than Hyponex media in all concentration levels except stem length. The activated charcoal concentration in MS media showed different effects on number of stem and root, leaf length, and fresh weight: the most effective in the range of 0.1 to 1.0 g/L and barely effective above 2.0 g/L. Addition of agar 5 g/L, sucrose at 40 g/L, and peptone at 1 g/L to MS media increased significantly stem length, leaf width, and fresh weight, internode length and number of roots, and the number of stem and leaves. On the other hand, addition of gelite with any concentration had no effect on the growth of micro stem cutting compare to that of control. The optimal temperature for growth of micro stem cutting was $28^{\circ}C$. Under the same temperature, MS medium was better than Hyponex medium for the growth of stem. In addition, sucrose at 40 g/L was the most effective on growth at $28^{\circ}C$.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.919-929
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• 2016

This study investigated the effect of organic materials (Bordeaux, Loess-sulfur) and the removal of apical shoot against downy mildew disease on cucumber cultivated in greenhouse. Five kinds of Bordeaux were made by adjusting mixing ratio of lime and copper sulfate in order to elucidate the optimal combination. The 4-6type Bordeaux was selected as the most effective combination for controlling cucumber downy mildew. Loess-sulfur showed inhibitory activity against cucumber downey mildew, but it was less effective than Bordeaux. It was confirmed that apical shoot cutting could reduce the incidence of cucumber downy mildew disease by 56.3%. When apical shoots of susceptible cucumber variety were cut at different leaf stages, disease incidence by early apical shoot cutting treatment was lower than that of late apical shoot cutting treatment. However in a resistant variety, 'Heukryungsamcheok', disease incidences of all cucumber apical shoot cutting treatments were lower than that of non-cutting treatment, but there was no differences between apical shoot cutting treatments due to low disease incidences. In addition, when organic materials and apical shoot cutting treatment were carried out in parallel, the combined treatments of organic materials and apical shoot cutting showed low disease incidence of cucumber downy mildew compared to untreated control. The lowest disease incidence of cucumber downy mildew was recorded in the combined treatment of 4-6type Bordeaux and apical shoot cutting. This study confirmed that apical shoot cutting can reduce the disease incidence of cucumber downy mildew and the combined treatment of apical shoot cutting and organic materials showed higher suppressive effect against cucumber downy mildew.

• KSBB Journal
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• v.31 no.1
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• pp.20-26
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• 2016

This study aims to examine the optimum blanching conditions as a pretreatment condition to improve the storage stability of Dolsan leaf mustard pickle. The effects of the blan- ching temperature and time were investigated at a temperature range of $80-100^{\circ}C$. Sampling was done for 1 month after a 5 days interval. The L value of the Dolsan leaf mustard was found to be the highest at $80^{\circ}C$. The cutting force increased as the blanching temperature increased. The tensile strength decreased at $95^{\circ}C$ and $100^{\circ}C$. In addition, the sensory evaluation scores were the best at $80^{\circ}C$. The storage stability was assessed at various blanching temperatures to increase the sinigrin content during storage. Liquid chromatography with photodiode array and tandem mass spectrometry (LC-PDA/MS/MS) analysis was conducted to identify and quantify the sinigrin content in the Dolsan leaf mustard. Sinigrin as an internal standard was co-injected into each sample solution. The sample was monitored by recording the ultraviolet absorbance at 228 nm and by electrospray ionization (ESI) positive ion mode in the m/z 50-1,500 range. Blanching the sample at $80^{\circ}C$ showed the highest sinigrin concentration during storage among various temperatures and the maximum concentration was 350 ppm at 15 days storage. Study on utilization of vegetable from food processing of leaf mustard and preservation conservation results suggest that blanching at $80^{\circ}C$ is expected to improve the palatability of the pickle.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.1
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• pp.39-46
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• 1996

The experiment was conducted to inxvestigate matter production ability and growth characteristic variation for Italian ryegrass seed of introduced variety and the different seed production time of the next generation in paddy field at Iksan and Kyehwa experiment field from 1987 to 1988. Germination rate is good at seed production of 35 days before and after heading with introducced variety. Also, Early growth before wintering, dead leaf rate and regenerating day is same tendendy. Panicle numbers per hill like that and heading date is for 15~20 days after heading seed is late about three days, but 35 days before and after heading seed is early about one day. Fresh and drymatter yield at the different cutting time shows decrease in 15~25 days after heading seed but 35 days before and after heading seed is same or increase trend, it's notable at Kyehwa paddy field in reclaimed land. In case of feed value according to cutting time differ little against introduced seed.