• Journal of Life Science
• /
• v.24 no.12
• /
• pp.1364-1370
• /
• 2014

Ascorbic acid (AA) is a multifunctional metabolite in plants that is essential for plant development and growth. We examined the effect of AA, an antioxidant, on the gravitropic response of primary roots in maize. The application of $10^{-3}$ M AA to the elongation zone did not affect the gravitropic response and slightly inhibited the root growth. However, treatment with both $10^{-5}$ M and $10^{-3}$ M AA at the root tip increased the gravitropic response and inhibited root growth. Differences in indole-3- acetic acid (IAA) activity between the upper and lower hemispheres of the root resulted in differential elongation along the horizontal root. Roots are extremely sensitive to IAA, and increasing the amount of IAA in the lower hemisphere of the root inhibited elongation. Therefore, we examined the effect of IAA in the presence of AA. The inhibitory effect of AA on the gravitropic response was greater in combination with IAA. To understand the role of AA in the regulation of root growth and the gravitropic response, we measured ethylene production in the presence of AA in the primary roots of maize. AA stimulated ethylene production via the activation of the 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene, which regulates the conversion of ACC to ethylene. These results suggest that AA alters the gravitropic response of maize roots through modification of the action of ethylene.

• Asian-Australasian Journal of Animal Sciences
• /
• v.10 no.2
• /
• pp.178-184
• /
• 1997

Purified diets containing five graded levels of lysine were fed to a total of 125 growing chicks (25 chicks per treatment) to evaluate lysine requirements for growth and maintenance. A model was developed to separate lysine requirement for maintenance from requirement for growth. Based on weight gain response, the daily lysine requirement for growth was 12.06 mg/g gain and the daily lysine requirement for maintenance was 0.332 times metabolic body size ($W^{0.75}$). Similarly, the lysine requirement for growth was 0.457 mg/mg nitrogen gain and the daily lysine requirement for maintenance was 0.344 times metabolic body size. The plateau of plasma lysine concentration was reached at 354.75 mg intake/day. The total lysine requirement was 414.27 mg/day or 1.0% of the diet, 420.11 mg/day or 1.01% of the diet based on weight gain response and N gain response, respectively. Previous lysine requirements for growing chicks of 1-28 days old were in close agreement with these estimates. As a percentage of protein, lysine requirement was calculated to be 7.3% and the reported lysine content of chick muscle crude protein of 7.46% was closely related.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.3
• /
• pp.388-394
• /
• 1999

Two experiments were conducted to subdivide isoleucine (exp. 1) and valine (exp. 2) requirements for maintenance from the requirements for growth of broilers aged 1 to 3 weeks. Purified diets were used, containing five graded levels of isoleucine and valine. Based on weight gain response, the isoleucine requirement for growth was 7.50 mg/g weight gain and the daily isoleucine need for maintenance (mg) was 0.044 per unit metabolic body size ($(Wg^{0.75})$). Based on the N gain response, the isoleucine requirement for growth was 0.317 mg/mg N gain and the daily isoleucine need for maintenance (mg) was 0.040 per unit metabolic body size $(Wg^{0.75})$. Based on weight gain and N gain response, the total isoleucine requirement was calculated 244 mg/day or 0.59% of the diet, 274 mg/day or 0.66% of the diet, respectively. From the relationship of weight gain and N gain, 5.07% of the retained protein was comprised of isoleucine; the reported isoleucine content of chick muscle was 4.42%. The valine requirement for growth was 9.84 mg/g weight gain and 0.36 mg/mg N gain whereas the maintenance requirement was 0.046 or 0.052 mg per unit of metabolic body size (Wgo.11. According to the model developed to estimate valine requirement, the total requirement was 319 mg/day or 0.77% of the diet, 315 mg/day or 0.76% of the diet, respectively. Previous reported valine requirements for growing chicks of 7~24 days old were in close agreement with these estimates. As a percentage of retained protein, valine was calculated to be 5.81% ; the reported valine concentration of crude protein of chicks' body including feathers was 6.72%.

• Journal of Environmental Science International
• /
• v.26 no.9
• /
• pp.1081-1086
• /
• 2017

The present study was conducted for the purpose of analyzing the growth response of Dracaena braunii treated with chloride ions and to evaluate its salt tolerance. Distilled water (CON) was spiked with 1 (C1), 2 (C2), 5 (C5), 10 (C10) and 15 g/L (C15) $CaCl_2$, respectively. Acidity (pH) and electrical conductivity of hydroponic solution, and leaf width, leaf length, root length, number of leaves, fresh weight, dry weight and the water content of Dracaena braunii were measured. Acidity and electrical conductivity remarkably increased commensurate with increasing concentrations of $CaCl_2$. Growth in the C1 treatment was better than that in CON, whereas the C10 or C15 treatments caused either slow growth or withering of the plants. Fresh weight, dry weight and water content were significantly decreased in response to $CaCl_2$ concentration, compared with those in the control. These results showed that $CaCl_2$ concentration less than 1 g/L may be used as a hydroponic solution for D. braunii, as long as the water quality is not too saline. The chlorine ion has a negative effect on the growth.

• Journal of Environmental Science International
• /
• v.7 no.2
• /
• pp.141-148
• /
• 1998

Effects of alumlnlum(AA), soil pH and calcium(Cal on growth response and heavy metal accumulation and regulation of nitrogen fixation In Melilotus suaveolens seedlings, a biennial legume plant dominating in the disturbed area, were quantitatively analyzed during the growing periods. Accumulation of metals In each organ of M. suaveojens was Increased UC the lowering of pH. Al contents In leaf and root treat- ed with 30ppm Al at pH 4.2 on the 28th day after treatment were 8 and 11 folds higher than those of control, while the contents with 100ppm AA were 21 and 24 folds as compared to control. The significent inhibition in Al contents was induced by 100ppm AA and Ca at pH 6.5. Increased metals inhibited higher at pH 4.2 and the growth inhibition due to Al was reversed by the addition of Ca, suggesting that growth correlates to the pH value. Chlorophyll contents in leaves increased during growth stave were inhibited by Al treatments. The biomass was decreased UD the lowering of pH and the increase of concentrations. 100ppm Ca treatment resulted in 5.1-5.9% increase of the biomass as compared to that of 100ppm Al. Specific nitrogen fuation activities In nodules In the 100ppm Al at pH 4.2 and pH 6.5 were reduced to 35. 2% and 52.2% of control, on the 28th day after treatment, while the combination of Al and Ca induced reduced by 10% as compared to control with the treatment of 100ppm AA at pH 4.2 due to the inhibition bination of 100ppm Al and Ca and lowering of pH.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.2
• /
• pp.259-270
• /
• 2020

Listeria monocytogenes is a gram-positive, facultative anaerobe food pathogen responsible for the listeriosis that mostly occurs during the low-temperature storage of a cold cut or dairy products. To understand the systemic response to a wide range of growth temperatures, L. monocytogenes were cultivated at a different temperature from 10℃ to 42℃, then whole cell proteomic analysis has been performed both exponential and stationary cells. The specific growth rate increased proportionally with the increase in growth temperature. The maximum growth rate was observed at 37℃ and was maintained at 42℃. Global protein expression profiles mainly depended on the growth temperatures showing similar clusters between exponential and stationary phases. Expressed proteins were categorized by their belonging metabolic systems and then, evaluated the change of expression level in regard to the growth temperature and stages. DnaK, GroEL, GroES, GrpE, and CspB, which were the heat&cold shock response proteins, increased their expression with increasing the growth temperatures. In particular, GroES and CspB were expressed more than 100-fold than at low temperatures during the exponential phase. Meanwhile, CspL, another cold shock protein, overexpressed at a low temperature then exponentially decreased its expression to 65-folds. Chemotaxis protein CheV and flagella proteins were highly expressed at low temperatures and stationary phases. Housekeeping proteins maintained their expression levels constant regardless of growth temperature or growth phases. Most of the growth related proteins, which include central carbon catabolic enzymes, were highly expressed at 30℃ then decreased sharply at high growth temperatures.

• The Korean Journal of Ecology
• /
• v.19 no.4
• /
• pp.285-294
• /
• 1996

Ring-width chronologies of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) from two experimental forest plots in Kaunas, Lithuania were developed to study tree growth-climate relationship in different geohydrological conditions using response function analysis. The tree ring-width chronologies of Scots pine ranged from 1883~1987 A.D. and 1864~1989 A.D., and Norway spruce 1838~1987 A.D. and 2870~1989 A.D., respectively. The response function analysis has vividly demonstrated that the growth of Scots pine is favoured by warm summer and Norway spruce by cool and moist summer. Spring temperature has shown direct relationship with tree growth of both the species. There also exists notable intraspecies analogies in growth responses except some minor differences.

• Korean Journal of Materials Research
• /
• v.21 no.4
• /
• pp.232-235
• /
• 2011

ZnO nanorods for gas sensors were prepared by a hydrothermal method. The ZnO gas sensors were fabricated on alumina substrates by a screen printing method. The gas-sensing properties of the ZnO nanorods were investigated for $CH_4$ gas. The effects of growth time on the structural and morphological properties of the ZnO nanorods were investigated by X-ray diffraction and scanning electron microscope. The XRD patterns of the nanocrystallized ZnO nanorods showed a wurtzite structure with the (002) predominant orientation. The diameter and length of the ZnO nanorods increased in proportion to the growth time. The sensitivity of the ZnO sensors to 5 ppm $CH_4$ gas was investigated for various growth times. The ZnO sensors exhibited good sensitivity and rapid response-recovery characteristics to $CH_4$ gas, and both traits were dependent on the growth time. The highest sensitivity of the ZnO sensors to $CH_4$ gas was observed with the growth time of 7 h. The response and recovery times were 13 s and 6 s, respectively.

• Journal of Environmental Science International
• /
• v.12 no.11
• /
• pp.1189-1196
• /
• 2003

The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• v.2 no.2
• /
• pp.82-95
• /
• 2021

Current international negotiation and cooperation for sustainable development are focused on three main themes. The first theme is implementation of Sustainable Development Goals (SDGs). The second theme is development of measures for climate change. The third theme is sustainable management of biodiversity and ecosystem services. In South Korea, responses of government policies and academic studies have been predominantly to one of these three themes. There have not been many integrated efforts to develop countermeasures considering all three international themes. In addition, while "green growth" policies have been setting national agendas for Korea's sustainable development, they must be scrutinized such as why they have not dealt with some parts of these three themes and whether they have ignored one of these themes due to lack of integrated responses. This study finds critical issues in South Korea on how to harmoniously respond to the three themes of international efforts and improve green growth policies. First, to achieve SDGs, the domestic statistical system must be reorganized to track the achievement of "inclusiveness" and "green growth". Second, the climate change response policy should seek inclusion between countries and between social groups. Third, in the field of biodiversity and ecosystem services, it is necessary to establish Korea's identity in global geopolitics and enhance its own traditional ecological knowledge. Fourth, it is necessary to consider how to solve discrepancy between climate change response policies and biodiversity-ecosystem service management policies. Finally, proactive improvement of laws and institutions must occur to promote inclusive green growth.