• Korean Journal of Ichthyology
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• v.21 no.3
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• pp.158-166
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• 2009

To obtain the fundamental data for the mass seedling production of grunt, Hapalogenys nitens, we investigated the influence of salinity and cold water temperature on hatching and survival of eggs and growth and survival of larvae and fry. In regards to salinity, we surveyed the hatching rate and floating rate of fertilized eggs, the floating rate and survival rate of hatching larvae, and the survival and growth of fry. In respect to cold temperature, we investigated the influence of degree of daily temperature decrease, acute temperature shock, and slow temperature decreases on the survival, feeding and swimming activities of fry. In the salinity experiment, the hatching and floating rates of fertilized eggs, and the floating and survival rates of hatching larvae, were shown to be higher in seawater than in brackish water. Growth and survival of larvae and fry were not different between seawater (25~32 psu) and brackish water (5~20 psu), but were significantly lower in freshwater. In the cold-temperature test, three tests showed that rearing of fry in cold water and acutely decreasing water temperature to less than $10^{\circ}C$ reduced the survival, feeding and swimming activities of the fry. Therefore, we concluded that low salinity (less than 32 psu) could reduce the hatching rate and survival of eggs, but the growth and survival of fry were not influenced by salinity, and cold water (less than $10^{\circ}C$) decreased metabolism of grunt. During winter, we found a low-temperature limit at $8^{\circ}C$.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.3
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• pp.97-105
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• 2013

Kalopanax septemlobus (Thunb. ex Murray) Koidz. is natively distributed in Korea. The importance of this species has been increased not only for high quality timber but for medicinal and edible uses. However, increasing market demand of K. septemlobus with illegal cutting and overexploitation has resulted in its rapid depletion and destruction of natural habitat. This study was conducted to understand the survival rate and growth characteristics of planted K. septemlobus seedlings with treatment of root pruning, stem cutting and planting density. The survival rate and growth of height and root-collar diameter for one- and two-year old seedlings with different planting densities were investigated in the clear-cut area of a Pinus densiflora stand for five years. One-year-old seedlings were treated with or without root pruning and planted with three density levels (5,000 trees $ha^{-1}$, 10,000 trees $ha^{-1}$, and 40,000 trees $ha^{-1}$). Two-year-old seedlings were treated with and without stem cutting and planted with the density of 5,000 trees $ha^{-1}$. The survival rate of one-year-old seedlings with root pruning treatment in the density of 10,000 trees $ha^{-1}$ was 92%, while that without root pruning in the density of 40,000 trees $ha^{-1}$ was 67% after five years. The height of one-year-old seedlings has been significantly affected only by planting density in the $5^{th}$ year. The survival rate of the two-year-old seedlings with stem cutting was 75.5% and greater than control (67.3%) in the $5^{th}$ year but no difference in height was shown between the two treatments from three years after plantation.

• Journal of Aquaculture
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• v.9 no.3
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• pp.215-222
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• 1996

An experiment was conducted to assess the effects of dietary 3,5,3'-triiodo-L-thyronine ($T_3$) at 0, 10, 20, 50, 100 ppm on growth and survival rate in juvenile black seabream held at $27.9{\pm}1.1^{\circ}C$ for 50 days. Fish were fed the $T_{3}$ experimental diet for 4() days by hand to satiation in $2{\~}4$ times per day. After 50 days period, food intake rate (${\%}$), feed efficiency (${\%}$), survival rate (${\%}$), growth of weight and length (specific growth rates), and condition factor were measured. Food intake rate was inversely related to the dietary $T_{3}$ level. But feed efficiency was not changed by $T_{3}$ level. $T_{3}$ slightly improved survival rate of larvae. Survival rate of larvae from 100 ppm was significantly higher than that of fish from control. Dietary $T_{3}$ influenced growth in length and weight. Growth of black seabream fed a diet containing 10 ppm of $T_{3}$ was significantly higher than that of fish fed control. However 100 ppm of $T_{3}$ induced the inhibition for length and weight growth. The condition factor was inversely related to the dietary $T_{3}$ content.

• The Korean Journal of Malacology
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• v.32 no.2
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• pp.103-109
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• 2016

The effect of different feeding rate on the growth and survival rate of 3-year-old abalone, Haliotis dicsus hannai were investigated in marine net cage culture. Feeding rate is determined that was fed 5, 10, 15 and 20 percentage to abalone at body weight once daily : 5 daily feeding rate (DFR), 10 DFR, 15 DFR and 20 DFR. After that, it was conducted to reared during thirteen month with two replicates in net cage culture. In the growth performance of reared abalone (initial mean shell length $73.77{\pm}11.27mm$) in net cage culture, that the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) to the shell length and shell breadth, as well as weight gain (WG), daily weight gain (DWG) and specific weight gain (SWG) to body weight of 5 DFR were higher than those of different groups (P < 0.05). Also, survival rate of all feeding rate groups was not significant, but it was showed bellow 30 percents. Therefore, these results is showed that the daily feeding rate for natural feed of 3-year-old abalones reared in net cage culture should be to supply among five to ten percents.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.273-276
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• 2001

In order to develop effective acclimatization methods for Aralia elata plantlets regenerated from somatic embryos, various acclimatizing conditions were compared regarding both survival rate and growth of the plantlets. The plantlets were transplanted into plastic boxes containing artificial soil in the presence of either several levels of MS liquid media, distilled water, 2% sucrose or 0.1% hyponex solution. They were then cultured by spraying of distilled water twice a week and maintained in the normal tissue culture room. Perlite was proved to be better than vermiculite on survival rate and growth of the plantlets. As the size of perlite (larger than 0.2 cm in diameter) increased, both the survival rate and growth of the plantlets improved. Among the various MS liquid media and different aqueous solutions tested, distilled water appeared to result in the best survival rate and growth. MS media were also effective in increasing survival rate and supporting growth when diluted to 1/4 and/or 1/8. The acclimatized plantlets could be transplanted directly onto the nursery bed and grown normally. The above results suggest that plantlets regenerated from somatic embryos of Aralia elata be effectively acclimatized using a plastic box containing perlite with distilled water treatment.

• Journal of Aquaculture
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• v.19 no.4
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• pp.242-246
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• 2006

Comparisons of growth and survival rate in different culture systems for juvenile abalone were determined in the West Coast of South Korea from June, 2000 to April, 2001. Daily growth rate reached at the maximum by $148.6{\pm}48.96\;{\mu}m/day$ with a stagnant system and at the minimum by $95.3{\pm}21.45\;{\mu}m/day$ with a sprinkler culture system. Survival rate of the juvenile abalone was significantly higher than that in sprinkler culture with a rotary culture (P<0.05). The highest survival rate was 50.0% in the rotary culture and 38.3% was observed in the stagnant culture system. The results from this study indicate that effective survival and growth rate could be predicted in the rotary culture system.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.485-489
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• 1999

The germination percentages of Quercus hybrid seeds produced in 1994 using stored pollens were low. The survival rate and height growth within 2 years differed according to crossing combinations. The survival rate and growth of seedlings from hybrid seeds produced in 1991 and 1993 were investigated. The survival rates of five-year-old and three-year-old seedlings were from 71 to 100% and from 33 to 100%, respectively. The survival rates differed according to cross combinations. The mortality of seedlings increased in proportion to the increase of percentages of dwarf seedlings. The growth of five-year-old seedlings, of which mother tree was Q. aliena, was the best. The growth of seedlings produced by artificial crossing tended to be worse than that of natural crossing.

• Journal of Practical Agriculture & Fisheries Research
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• v.19 no.1
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• pp.15-23
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• 2017

Effects of artificial releases of sea cucumber around the marine ranching area in Jeollanam-do were showed very efficient by the released good seeds(total weight, 3.2g) in 'Wolhang', compared with those in 'Hwatae'. The survival rates were the higher in 'Wolhang' by 66.0% than in 'Hwatae' by 27.0%. The results indicates that the releasing effect of sea cucumber depended on the releas size. To analyze the productivity we investigated the growth and survival rates of sea cucumber according to the releasing area. Our result showed that the growth rate and survival rate was higher in 'Hwatae' than other areas. In 'Hwatae', the growth rate and survival rate were 6.2g and 32.1% respective. The results indicates that if the food supply is continued, although proceeding contamination the productivity of sea cucumber increased. Therefore, in order to enhancement and conservation of resource, bottom of fish cage should consider to the utilization.

• Journal of Radiation Industry
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• v.5 no.3
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• pp.211-220
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• 2011

This study was carried out to develop salt tolerant varities of rapeseed (Brassica napus L.) which can be grown in the high salty reclaimed land. The seeds of three varieties 'Naehan', 'Tammi', and 'Halla' were treated by proton ion beams and gamma rays with 0 to 2,000 Gy. For the selection of salt tolerant lines, emergence and survival rate, and growth characteristics of $M_2$ to $M_4$ generations were investigated in the Saemangeum reclaimed fields with the different salt concentrations. The lines with potential salt tolerance were selected in the $M_4$ generation and tested indoor for their growth characteristics. There was no significant changes in the soil pH for $M_4$ generation during growth period. However, soil EC was higher in early spring than sowing period (mid October). In $M_4$ generation test, the seeds of original and selected line showed high rates of emergence and survival, as determined one month after sowing. After wintering, however, the original varieties showed the significant reduction in the survival rate, while the selected lines showed a higher survival rate and good growth, leading to the completion of their life cycle. Consequently we selected 9 lines from $M_4$ generation with better performance in growth and yield. Soil EC was $2.8{\sim}4.3dS{\cdot}m^{-1}$ during $M_4$ generation growth period. The laboratory test of the lines selected from $M_4$ generation was made for their salt tolerance potential. The selected lines showed higher chlorophyll and proline contents than the original varieties. There was also no significant difference in the emergence rate of seed between the original and selected varieties. In 200 mM natural sea salt, the $N{\gamma}600-21-1-641$ line derived from 'Naehan' was the highest in growth rate, leaf chlorophyll and proline contents. $T{\gamma}800-20-2-461$ line derived from 'Tammi' didn't show significant difference in growth rate compared to original variety in 200 mM and withered in 250 mM like other lines as time passed. $H{\gamma}200-7-1-740$ line showed similar growth and chlorophyll content compared to its original variety.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.39-43
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• 2003

Experiments were carried out to investigate the effects of long term sub-lethal cadmium exposure on survival, growth and metabolic rate of olive flounder, Paralichthys olivaceus for 6 weeks. Survival rate of the flounder was significantly affected above $980{\mu}g/L$. Growth rates of the flounder exposed to ${\geq}210\;{\mu}g/L$ of cadmium concentration were significantly decreased than that exposed to normal condition, Metabolic rate in the cadmium concentration ${\geq}210\;{\mu}g/L$ was significantly reduced with increasing cadmium concentration than that in normal condition. This study revealed that high cadmium concentration $$({\geq}210\;{\mu}g/L$$ reduced growth and metabolic rate of the juvenile flounder suggesting potential influence on the natural mortality of olive flounder in the coastal areas.