• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.70-79
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• 2002

This study was conducted to determine correlations and combining abilities of leaf lengths, leaf widths, petiole lengths, number of branches, number of leaves, leaf areas, fresh weights, dry weights and number of flowers in F₁ crosses made with the partial seven-parent diallel cross in Viola tricolor. Leaf lengths and leaf widths showed highly positive correlation with petiole length and negative correlation with number of branches, number of leaves and number of flowers. There was positive correlation between the number of leaves and flowers as well as between leaf area and fresh weight. Mean squares of general combining ability(GCA) and specific combining ability(SCA) were highly significant for all the parameters. Variance component values of SCA were greater than those of GCA for all the parameters except leaf length, implying preponderance of non-additive gene actions for these characters. The lines C and G for leaf lengths and widths, the lines A and F for number of leaves, the lines A, B and G for leaf areas, and the lines B and F for number of flowers showed relatively high GCA effects. The crosses of A×B and B×D exhibited high SCA effects on increasing leaf lengths, leaf widths, number of leaves, fresh weights and number of flowers. And also the crosses of B×E and D×G exhibited high SCA effects on decreasing leaf lengths, leaf areas and fresh weights as well as increasing number of flowers. The broad sense heritabilities of most characters were high compared with the narrow sense one. Those of leaf length, leaf width, petiole length and number of leaves were high in both the broad and narrow sense heritabilities.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.4
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• pp.1798-1802
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• 1969

The experiment was carried out as one of the basic studies to improve the alkali-resistance of cement mortars and it was conducted to investigate some propetties of mortars relating to weight losses when exposed to 0.1 N salution of sodium hydroxide. The experiment and the results obtained are summarized as follow; 1. The specimens used in this experiment were made of 5 centi-meter cubes of mortar having such various ratios of mix by weight as 1 : 1, 1 : 3, 1 : 5, 1 : 7 and 1 : 10. 2. Physical tests included compressive strengths at 7 days, 28 days, 3 months, and 6 month, and 5 hour boiling absorption test. 3. In alkali test, every specimen was immersed into 0.1 N solutions of sodium hydroxide. The specimens exposed to the alkali solution were weighed to determine the weight losses of the alkail-corroded at one week interval for 7 week's exposure and the old alkali solutions were also changed to fresh solutions when weighed the weight losses by alkali attack at one week interval. 4. According to the alkail test after 7 week's exposure, no weight losses were observed on ratios of mix 1:1 and 1:3 and slight weight losses occurred on ratios of mix 1:5 and 1:7, but relatively large amount of weight losses were showed by 36.6 per-cent on ratios of mix 1:10. It was also found that the weight losses of the alkali-corroded were extremely lower than those of the acid-corroded at the some concentrations as 0.1 N of solutions. 5. In order to make better quality of alkali-resistant mortar it might recomend that a 1:7 mix or richemixes, use of small amount of mixing water for watertight, 20 per cent or less absorption by 5 hour boiling 1,600 kirogram per cubic meters or denser densities by absolute dry base are available for physical properties of mortar. It could conclude acid-resistant mortars were so high alkali-resistant, that it is expected to make and improve the acid-resistant mortars for getting rid of damages by alkali attack.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.397-403
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• 2015

Heavy metals reduce the photosynthetic efficiency and disrupt metabolic reactions in a concentration-dependent manner. Moreover, by replacing the metal ions in metalloproteins that use essential metal ions, such as Cu, Zn, Mn, and Fe, as co-factors, heavy metals ultimately lead to the formation of reactive oxygen species (ROS). These, in turn, cause destruction of the cell membrane through lipid peroxidation, and eventually cause the plant to necrosis. Given the aforementioned factors, this study was aimed to understand the physiological responses of rice to cadmium (Cd) and arsenic (As) toxicity and the effect of essential metal ions on homeostasis. In order to confirm the level of physiological inhibition caused by heavy metal toxicity, hydroponically grown rice (Oryza sativa L. cv. Dongjin) plants were exposed with $0-50{\mu}M$ cadmium (Cd, $CdCl_2$) and arsenic (As, $NaAsO_2$) at 3-leaf stage, and then investigated malondialdehyde (MDA) contents after 7 days of the treatment. With increasing concentrations of Cd and As, the MDA content in leaf blade and root increased with a consistent trend. At 14 days after treatment with $30{\mu}M$ Cd and As, plant height showed no significant difference between Cd and As, with an identical reduction. However, As caused a greater decline than Cd for shoot fresh weight, dry weight, and water content. The largest amounts of Cd and As were found in the roots and also observed a large amount of transport to the leaf sheath. Interestingly, in terms of Cd transfer to the shoot parts of the plant, it was only transported to upper leaf blades, and we did not detect any Cd in lower leaf blades. However, As was transferred to a greater level in lower leaf blades than in upper leaf blades. In the roots, Cd inhibited Zn absorption, while As inhibited Cu uptake. Furthermore, in the leaf sheath, while Cd and As treatments caused no change in Cu homeostasis, they had an antagonist effect on the absorption of Zn. Finally, in both upper and lower leaf blades, Cd and As toxicity was found to inhibit absorption of both Cu and Zn. Based on these results, it would be considered that heavy metal toxicity causes an increase in lipid peroxidation. This, in turn, leads to damage to the conductive tissue connecting the roots, leaf sheath, and leaf blades, which results in a reduction in water content and causes several physiological alterations. Furthermore, by disrupting homeostasis of the essential metal ions, Cu and Zn, this causes complete heavy metal toxicity.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.1
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• pp.49-64
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• 1989

The study was carried out to investigate the effect of control leaf number on growth and chemical characteristics, and on yield and quality In (rue-cured tobacco The rest upper leaves of 14, 16, and 18 leaves per plant were removed at button stage, and the plants were harvested :0, 12, and 16 leaves with discard 4 leaves of the bottom, respectively. 1. There were showed a tendency to increase in length (LL), width (LW), area (LA), fresh (LFW) and dry weight (LDW) per leaf as leaf numbers were decreased, while those per plant and the ratios of increase of those per plant were decreased. 2. In compensation effect (CE), there were increase in LL, LFW, LDW, LL/LW and LDW/LFW with each decreased in leaf numbers while LW was decreased, LA unchanged. 3. There were significant Increases in LL, LW, and LA at 5th~8th stalk positions form bottom (SP), while those .at 13th~16th SF were decreased. Also, LDW at 5th~l0th, and LDW/LFW and weight Per unit leaf area at 11th 16th were Increased as leaf numbers decreased. 4. Mean per plant and CE of nicotine were increased, but those of sugar were decreased with each decrease In leaf numbers. In addition, nicotine contents at 5th~14th SP except for 9th~10th were increased, otherwise sugar contents at 7th~14th were decreased. 5. There were showed a tendency to increase in grade per Plant and in tirade at 5th~8th SP, but decrease in CE of grade as leaf numbers were decreased. There wee significant decrease in grade at 11th~14th SP. Also, ratio of 5 grade was decreased, while ratios of 3 and 4 grades were increased. 6. When the 2 leaves at 3rd~4th SP were harvested, price was decrease 2.6% and yield was increased 5.8 %. 7. When the 6 leaves from convention were removed at but ton stage, effects of apparent, compensational, and net per leaf on yield were -3.9%, +2.6%, and -6.5%, respectively, and those on price were +1.1%, -1.6% and +2.7%, respectively.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.55-62
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• 2010

This study was conducted to find out the effect of diniconazole treatment by seed soaking on the stretching of tomato and cucumber seedlings. The emergence rate of tomato and cucumber seed was decreased as diniconazole concentration was higher and soaking period was longer. The emergence rate of tomato seedlings was lower as the soaking period was longer in $1mg{\cdot}L^{-1}$ concentration treatments, although there was no significant difference. The other concentration treatment (10, 50, and $100mg{\cdot}L^{-1}$) reduced emergence rate of tomato seedlings outstandingly in higher concentration and longer treated period, but 90% of treated seeds emerged at 10 days after sowing. As the concentration of diniconazol was higher and soaking period was longer, plant height and growth rate of seedlings were retarded. There covery of internodes growth was faster in lower concentration and shorter soaking period. The top and root fresh weight and dry weight of tomato and cucumber seedlings was not influenced by $1mg{\cdot}L^{-1}$ concentration, but these growth characteristics were reduced in higher concentration and longer soaking period. The dwarfed cucumber seedlings treated by diniconazol showed normal growth rate after planting and their male and female flower was set normally. These results suggest that the proper concentration and soaking period of diniconazol may be $10mg{\cdot}L^{-1}$ concentration for 12 hours in tomato seed, and $1mg{\cdot}L^{-1}$ concentration for 24 hours in cucumber seed.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.631-639
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• 2011

This research was conducted to investigate potential use of New Zealand spinach (Tetragonia tetragonoides) as a new vegetable crop which will be cultivating in salt-affected soils including reclaimed land. Traditionally New Zealand spinach has been studied to explore functional compound or salt removing potential. To cultivate the crop species in the salt-affected soil widely, it is essential to obtain salt and soil texture responses under the controlled environment. Fifty nine New Zealand spinach ecotypes native to Korean peninsula first collected over seashore areas, and primitive habitat soil environment was evaluated by analyzing soil chemical properties from 32 locations. Different textures of sandy, silt loam, and sandy loam soils were prepared from nearby sources of sea shore, upland and paddy soils, respectively. Target salinity levels of 16.0 dS/m, 27.5 dS/m, 39.9 dS/m, and 52.4 dS/m in electrical conductivity (ECw) were achieved by diluting of 25, 50, 75, 100% (v/v) sea water to tap water (control, 0.6 dS/m), respectively. Various measurements responding to soil texture and irrigation salinity included plant height, root length, fresh weight (FW), dry weight (DW), leaf parameters (leaf number, leaf length, leaf width), lateral branching, and inorganic ion content. was found to adapt to diverse habitats ranging various soil chemical properties including soil pH, organic matter, exchangeable bases, EC, and cation exchange capacity (CEC) in Korea. Responding to soil texture, New Zealand spinach grew better in silt loam and sandy loam soil than in sandy soil. Higher yield (FW and DW) seemed to be associated with branch number (r=0.99 and 0.99, respectively), followed by plant height (r=0.94 and 0.97, respectively) and leaf number (r=0.89 and 0.84, respectively). Plant height, FW, and DW of the New Zealand spinach accessions were decreased with increasing irrigation salinity, while root length was not significantly different compared to control. Based on previous report, more narrow spectrum of salinity range (up to 16 dS/m) needs to be further studied in order to obtain more accurate salinity responses of the plant. As expected, leaf Na content was increased significantly with increasing salinity, while K and Ca contents decreased. Growth responses to soil texture and irrigation salinity implied the potential use of New Zealand spinach as a leafy vegetable in salt-affected soil constructed with silt loam or sandy loam soils.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.123-127
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• 2013

BACKGROUND: The incandescent bulb and compact fluorescent lamp are widely using as a light sources for daylength extension of chrysanthemum. But, these light sources consume a lot of electricity and have short longevity. A light-emitting diode (LED) is a semi conductor light source. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime. In this study, we investigated the intensity of red light to control flowering of chrysanthemum (Dendranthema grandiflorum cv. "Shinma") by using LEDs. METHODS AND RESULTS: The red (660 nm) and far-red (730 nm) light were irradiated subsequently to investigate photo-reversible flowering responses of chrysanthemum. The flowering of chrysanthemum was inhibited by night interruption with red light but subsequently irradiated far-red light induced the flowering of chrysanthemum. This photoreversibility, reversion of the inductive effect of a brief red light pulse by a subsequent far-red light pulse, is a property of photo responses regulated by the plant photoreceptor phytochrome B. Four different intensity of red light of 0.7, 1.4, 2.1, and $2.8{\mu}mol/m^2/s$ (PAR) were irradiated at growth room in order to determine the threshold for floral inhibition of chrysanthemum. Over $1.4{\mu}mol/m^2/s$ of the red lights irradiated chrysanthemums were not flowered. The plant length, fresh weight, number of leaves, and leaf area of chrysanthemum irradiated with red light were increased by 17%, 36%, 11%, and 48%, respectively, compared to those of compact fluorescent lamp. CONCLUSION(S): The red light and subsequential far-red light showed that the photoreversibility on flowering of chrysanthemum. The red light ($1.4{\mu}mol/m^2/s$ of red LEDs) and white light (50 Lux of compact fluorescent lamp) have the same effect on inhibition of flowering in chrysanthemum. Additionally, the red light increased the plant height and dry weight of chrysanthemum.

• Korean Journal of Poultry Science
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• v.11 no.2
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• pp.93-98
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• 1984

Four different silages were prepared out of citrus peel with or without supplementation with wheat bran and/or urea. Proximate nutrients and volatile fatty acids were analysed on the silages, both fresh and dried. All silages were dried and ground, and were compared with dried citrus peel (not ensiled) and wheat bran in a folding trial. A total of 360 male chicks of Maniker broiler strain was divided into and assigned to 6 treatments with 5 replications. Each experimental diet included each of 6 test material at the level of 6% and the feeding trial lasted 8 weeks, after which a metabolism trial was conducted. Results obtained were summarized as follows. 1. Ensiling increased protein content of the citrus peel on the dry matter basis and supplementing the silage material with wheat bran and/or urea further increased protein contents of the silages. 2. Adding wheat bran and/or urea to silage material also increased volatile fatty acid contents of the silages. After drying organic acid contents of the silages were reduced and there were no differences in organic acid contents of the dried citrus peel silages, differently treated, 3, Broilers fed dried citrus peel and those fed dried citrus peel silages gained numerically less weight than those fed wheat bran. But there were no significant differences in body weight gain, feed intake and feed efficiency among different treatments 4. There were no significant differences in nutrient utilizability, nitrogen retention and metabnlizable energy contents among treatments. It could be concluded that ensiling is an effective way of storing citrus peel and dried citrus peel silage could be used in broiler diets up to 6% without adverse effects.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.263-268
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• 2011

This study was carried out to investigate the effect of nursery period and block size on seedling quality and fruit yield of paprika (Capsicum annuum L. 'Cupra'). Seeds of paprika (Capsicum annuum L., Cupra) were sown in rockwool plugs. Seedlings were transferred and grown to the rockwool block different sizes: $5{\times}5$, $7.5{\times}7.5$ and $10{\times}10cm$ at sowing after 15 days. The plants were transplanted by 25, 30, 35, 40, 45 and 50 days we planted the seeds to the rockwool slabs. Seedling growth was not influenced by block size in the 25 day old plant, since then growed poorly with increasing nursery period in the $5{\times}5cm$ block size, plant height, stem diameter, fresh weight, dry weight have no difference from $10{\times}10cm$ and $7.5{\times}7.5cm$, but leaves and leaf area were higher $10{\times}10cm$ than the $7.5{\times}7.5cm$ block size. Growth of the paprika in field 80 days after sawing did not differ from nursery period and block size below 35 days old, but decreased with increasing nursery period and decreasing block size beyond 40 days old. Flowering did not differ from nursery period and block size below 35 days, but delayed with increasing nursery period and decreasing block size beyond 40 days old. The highest yield was obtained from 30 and 35 days old, and decreased with increasing nursery period and decreasing block size beyond 40 days old.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.148-156
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• 2016

This study examined effects of Enterobacter ludwigii SJR3 showing a high 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, on growth of tomato plant and its expression of stress-related genes under drought and salt stress. SJR3 strain was inoculated at $10^6cell/g$ soil to 4-week grown tomato plants, and drought and salt stresses were treated. After additional incubation for 1 week, root length, stem length, fresh weight and dry weight of tomato plants treated with SJR3 increased by 37.8, 37.2, 96.8 and 146.6%, respectively compared to those of uninoculated plants in drought stress environment, and they increased by 19.2, 25.4, 19.5, and 105.8%, respectively in salt stress environment. Proline content in tomato leaves increased significantly under stress conditions as one of a protecting substance against stresses, but proline contents in tomato treated with SJR3 decreased by 62.1 and 54.1%, respectively. Relative expression of genes encoding ACC oxidase, ACO1 and ACO4, ethylene response factor genes ERF1 and ERF4, and some other stress-related genes were examined from tomato leaves. Compared to the non-stressed tomato, expressions of all stress-related genes increased significantly in the stressed tomato, but gene expressions in the inoculated tomato were similar to those of no-stressed control tomato. Therefore, E. ludwigii SJR3 may play an important role in mitigating drought and salt stress in plants, and can increase productivity of crops under various abiotic stresses.