• ALGAE
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• 제19권4호
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• pp.303-309
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• 2004

The laboratory culture study of Porphyra seriata Kjellman from Korea was conducted at different conditions of temperatures (5, 10, 15, 20, 25 and 30${^{\circ}C}$), photon flux densities (10, 20, 40 and 80 $\mu$mol $^{-2}s^{-1}$) and photoperiods (14L: 10D and 10L:14D). Conchocelis filaments grew fast at 15-20${^{\circ}C}$ and 20-80 $\mu$mol $^{-2}s^{-1}$ under both photoperiods. Concho sporangial branches were produced at 5-25${^{\circ}C}$, and abundant when the conchocelis filaments were cultured at higher temperatures of 20-25${^{\circ}C}$ under both photoperiods. Foliose thalli grew well at 15-20${^{\circ}C}$ under 10L:14D and at 20${^{\circ}C}$ under 14L:10D. At 30${^{\circ}C}$, the foliose thallus failed to survive. No archespores were observed at any culture conditions. Spermatangia and zygotosporangia were formed in squarish patches at the upper marginal portion of mature thalli. Anatomical examination revealed that the mature spermatangia were 64 (a/4, b/2, c/8) and 128 (a/4, b/4, c/8), and that of zygotosporangium was 16 (a/2, b/2, c/4) according to the Hus' formula.

• 한국수산과학회지
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• 제48권1호
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• pp.76-81
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• 2015

The effects of temperature, photon irradiance, and photoperiod on the growth of Sargassum horneri embryos were examined for female plants collected at Chokpo in Tongyeoung, Gyeongnam Prefecture, Korea on 27 December 2011. Mature plant receptacles were detached, and fertilized eggs were cultured in the laboratory at temperatures of $5-25^{\circ}C$ with photon irradiances of $10-80{\mu}mol\;m^{-2}s^{-1}$ under 14L:10D and 10L:14D photoperiods. Germination and embryo growth were rapid at $20-25^{\circ}C$ and $40{\mu}mol\;m^{-2}s^{-1}$ under 14L:10D. The number of rhizoids in the germinated young thalli was high at high photon irradiances ($40-80{\mu}mol\;m^{-2}s^{-1}$) and $15-20^{\circ}C$. At $20^{\circ}C$ and 14L:10D, vigorous growth of main and lateral branches was observed; however, at $5^{\circ}C$ under both photoperiods, plant growth decreased markedly. In the present study, S. horneri grew well at high temperatures ($20-25^{\circ}C$) and high photon irradiances ($40-80{\mu}mol\;m^{-2}s^{-1}$) with a 14L:10D photoperiod.

• 대한수의학회지
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• 제55권2호
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• pp.111-116
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• 2015

In the present study, the effects of different photoperiods on stress, immunity, and hematological parameters in ICR mice were evaluated. Fifty male ICR mice 7 weeks old (body weight, $27.3{\pm}2.5g$) were divided into five groups: DP-0 (0/24-h light/dark cycle), DP-6 (6/18-h light/dark cycle), DP-12 (12/12-h light/dark cycle), DP-18 (18/6-h light/dark cycle), and DP-24 (24/0-h light/dark cycle). During the experimental period, no significant differences in body weight or feed intake were observed between the groups. Hematological analysis revealed that white blood cell, red blood cell, and hemoglobin values for the DP-0 group were significantly different compared to those of the other groups. After 28 days, no significant difference in serum cortisol concentration was observed among the groups, but serum cortisol levels increased in a light exposure-dependent manner. Total serum immunoglobulin G (IgG) concentrations of the DP-0 and PD-6 groups were significantly increased compared to those of the other groups (p < 0.05), and serum total IgG levels decreased in a light exposure-dependent manner. Results of the present study indicated that various photoperiods affect hematological parameters and total serum IgG levels in ICR mice while having no significant effects on body weight, feed intake, or cortisol levels.

• 한국발생생물학회지:발생과생식
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• 제6권1호
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• pp.45-54
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• 2002

골든 햄스터의 생식활동은 광주기에 의해 조절된다. 그들의 생식능력은 여름에 왕성하고 겨울에는 퇴화한다. 송과선에서 분비되는 멜라토닌은 계절적 번식동물에서 생식활동을 중재한다. 멜라토닌 수용체가 최근에 사람을 포함하는 몇몇 동물에서 확인되었지만 골든 햄스터의 생식능력과 관련하여 알려진 바가 많지 않다. 역전사 PCR 방법을 사용하여 멜라토닌 수용체의 일부 유전자를 동정하였다(309 염기). 멜라토닌 수용체의 핵산 서열과 추론된 아미노산 서열을 보고된 다른 동물들과 비교하였다. 멜라토닌 수용체는 시상하부, 뇌하수체, 혈액, 지라에서 명백히 탐지되었다. 광주기가 정소 무게 및 생식 호르몬에 현저한 영향을 주었지만 멜라토닌 수용체의 발현에는 영향을 뚜렷하게 보이지 않았다. 이러한 결과는 생식을 조절하는 멜라토닌은 그 수용체의 수보다 수용체에 결합하는 친화도가 더 중요함을 시사한다.

• Ocean and Polar Research
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• 제32권3호
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• pp.229-236
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• 2010

A study was conducted to investigate the effect of water temperature and photoperiod on the oxygen consumption of the fasting juvenile Pacific cod Gadus macrocephalus (mean body weight 79.9${\pm}$2.0 g) in order to quantify metabolic response of the species under given conditions. The oxygen consumption rate (OCR) of G. macrocephalus was measured under a combination of four different water temperatures (7, 10, 13 and $16^{\circ}C$) and three different photoperiods (24L:0D, 12L:12D and 0L:24D) with an interval of 5 minutes over a 24-hour period using a closed recirculating respirometer. Three replicates were set up in each treatment. OCRs increased with increased water temperatures under all photoperiod conditions (P<0.001). Mean OCRs at 7, 10, 13 and 16oC ranged from 793.7~1108.4, 1145.7~1570.3, 1352.8~1742.5 and 1458.2~1818.6 mg $O_2$ $kg^{-1}$ $h^{-1}$, respectively. Under all water temperature conditions except $7^{\circ}C$ (P<0.001), mean OCRs of G. macrocephalus were the highest in continuous light (24L:0D) followed by 12L:12D and 0L:24D photoperiods. Mean OCRs of fish exposed to the 12L:12D photoperiod were significantly higher during the light phase than during the dark phase under all temperature conditions (P<0.001). $Q_{10}$ values ranged from 3.19~5.13 between 7 and $10^{\circ}C$, 1.41~1.74 between 10 and $13^{\circ}C$ and 1.15~1.35 between 13 and $16^{\circ}C$, respectively. Based on overall results, water temperature, photoperiod and their combinations exerted a significant influence on the metabolic rate of juvenile cod. This study provides empirical data for estimating the amount of oxygen demand and managing the culture of cod under the given water temperatures and photoperiods.

• 한국양식학회지
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• 제13권4호
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• pp.295-301
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• 2000

1996년 2월 24일 전남 진도에서 채집한 넓은둥근돌김을 엽상체기와 사상체기의 생장, 성숙에 미치는 온도, 광량, 광주기의 영향을 구명하고 둥근돌김과의 생리특성을 비교하고자 수행하였다. 넓은둥근돌김의 엽상체와 사상체는 장.단일하의 5~$25^{\circ}C$에서 생장하며 엽상체는 장일하의 15$^{\circ}C$와 단일하의 10, 15$^{\circ}C$에서 생장과 성숙이 이루어졌고 엽형은 단일하의 1$0^{\circ}C$에서 천연의 조체와 비슷한 폭이 넓은 둥근형으로 되었다. 사상체의 생장은 양광주기하의 2$0^{\circ}C$이상, 40~80${\mu}$mol m$^{-2}$s$^{-1}$의 광량조건에서 빨랐으며, 광주기는 단일조건에 비하여 장일조건이 더 빨랐다. 각포자낭의 형성은 장, 단일하의 15~$25^{\circ}C$에서 나타났으며 각포자낭 형성시기 및 형성률은 단일하의 $25^{\circ}C$에서 빠르고 높게 나타났다. 이상의 결과에서 넓은둥근돌김은 엽상체 및 사상체기에 있어서 둥근돌김과는 다른 생리특성을 갖는 것으로 밝혀졌다. 따라서 넓은둥근돌김은 장일, 고온하의 조건이 5월 이후에도 천연에서 생육 가능성이 높은 것으로 추정되며 하기에도 유아 상태로 여름을 지날 수 있는 가능성이 높은 것으로 시사되었다.

• 수산해양교육연구
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• 제24권6호
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• pp.845-853
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• 2012

To investigate the role of temperatures and photoperiods as environmental cues regulating reproductive rhythm in Pseudobagrus fulvidraco, rearing experiments were conducted using sveral rearing regimes conbined with photoperiods and water temperatures during gonadal degeneration periods. Gonadosomatic index (GSI) in control was $8.16{\pm}1.50%$, while in other experiment GSI levels in female were lower than that in the control. In case of experimental precinct of 9 light (L) and 15 L, GSI levels were decreased. But GSI level with $20^{\circ}C$ was no diffrence after 40 and 60 days. GSI level in male of control was $0.35{\pm}0.05%$. GSI under 9 L and $25^{\circ}C$ was similar to that in control, whereas its level in other experiments was lower than that in control. Testosterone (T) of female was $3.68{\pm}0.22$ ng/mL at experimental precinct. In case of 9 L and 15 L, concentration of T were lower than experimental precinct in all of water temperature. Estradiol-$17{\beta}$ ($E_2$) and $7{\alpha}$, $20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}OHP$) levels of female were $0.42{\pm}0.02$ and $0.83{\pm}0.01$ ng/mL at experimental precinct. $E_2$ levels of 9 and 15 L were higher than experimental precinct and $17{\alpha}20{\beta}OHP$ levels of 9 and 15 L were higher than experimental precinct. In case of T and 11-ketotestosterone levels were $0.69{\pm}0.11$ and $.62{\pm}0.03$ ng/mL in male. During the period of gonadal degeneration, gonadal maturation did not occur in any of the experimental regimes. However, comparatively high levels of $E_2$ observed at low temperature regimes ($20^{\circ}C$) regardless of photoperiods.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1997년도 추계 학술대회지
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• pp.60-61
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• 1997

• International Journal of Industrial Entomology and Biomaterials
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• 제1권2호
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• pp.137-141
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• 2000

To determine effects of temperatures and photoperiods on larval development of the mulberry longicorn beetle, Apriona germari, the larvae were reared at various rearing temperatures and under the various photoperiods on an artificial diet. The larval period of A. germari was extended as long as the temperature was lowered. Also the larval development in terms of length and weight of larvae was increased. However, survival rate during larval stage significantly decreased at 15$^{\circ}C$ and $20^{\circ}C$ than at $25^{\circ}C$ and $30^{\circ}C$. The results indicated that the favorable temperature for artificial diet rearing of A. germari fell at least above $25^{\circ}C$ constantly. In photoperiod conditions, survival rate and larval development for A. germari were obviously most effective under a photoperiod of 14L:10B. As a result in artificial diet rearing of a. germari at $25^{\circ}C$ and under a photoperiod of 14L:10D was mostly favorable in terms of larval development and period.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권1호
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• pp.83-86
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• 2001

Effects of photoperiods, 24L or 24D, on the growth of the silkworm-dongchunghacho, the silkworm vegetable wasp and plant worm, were investigated. Exposure of the fungi under the photoperiod of 24L for at least 3 days during the cultivation of the fungi after the completion of endosclerotium in the host accelerated the spore formations but the growth of the fruiting bodies was inhibited. On the contrary, the photoperiod of 24D inhibited the spore formation, but accelerated the growth of fruiting bodies without spores. Accordingly, to produce silkworm vegetable wasp and plant worm of large-size fruiting bodies with over 3 cm in length, it is indicated that recommendable light condition is a photoperiod of 24D during the cultivation until the length of the fruiting body arrives at over 3 cm.