• Journal of Microbiology and Biotechnology
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• v.29 no.9
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• pp.1453-1459
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• 2019

Zeaxanthin is an important pigment in the photo-protection mechanism of microalgae. However, zeaxanthin epoxidase, an enzyme involved in the accumulation and conversion of zeaxanthin, has not been extensively studied in microalgae. In this work, we report the expression pattern of zeaxanthin epoxidase in Dunaliella tertiolecta (DtZEP) at different light and diverse salinity conditions. To confirm the responsiveness to light conditions, the ZEP expression pattern was investigated in photoperiodic (16 h of light and 8 h of dark) and continuous (24 h of light and 0 h of dark) light conditions. mRNA expression levels in photoperiodic conditions fluctuated along with the light/dark cycle, whereas those in continuous light remained unchanged. In varying salinity conditions, the highest mRNA and protein levels were detected in cells cultured in 1.5 M NaCl, and ZEP expression levels in cells shifted from 0.6 M NaCl to 1.5 M NaCl increased gradually. These results show that mRNA expression of DtZEP responds rapidly to the light/dark cycle or increased salinity, whereas changes in protein synthesis do not occur within a short period. Taken together, we show that DtZEP gene expression responds rapidly to light irradiation and hyperosmotic stress. In addition, ZEP expression patterns in light or salinity conditions are similar to those of higher plants, even though the habitat of D. tertiolecta is different.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.151-154
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• 2003

The effect of photoperiodic regimes on the oviposition and colony development of Bombus ignitus queens was examined with 0L, 8L, and 16L under $27^{\circ}C$ and 65% R. H. Among these photoperiod regimes, the oviposition rate at 8L and 16L was 80.2% and 83.1%, respectively, which was 12-15% higher than that at the dark condition (0L). Duration up to first oviposition at 8L and 16L was 17.5 days and 16.5 days, respectively, which was 2-3 days shorter than that at 0L. The colony foundation rate at 8L and 16L was 9.2% and 10.4%, respectively, which corresponded to 1.7-2.0-fold higher than the value at 0L. In addition, the rate of progeny-queen production at 8L and 16L was also two fold higher than that at 0L. Taken these together, the light conditions (8L and 16L) rather than dark condition (0L) were more suitable for oviposition and colony development for B. ignitus in the indoor rearing condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.111-115
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• 1970

1. Eight Varieties of Nicotiana tabacum, "Yellow special A", "Gold leaf", "Oxford, " "Awha", "Yungzung", "Samsun", "Maruha" and "Hatano" were compared on the photoperiodic responses. 2. Experiments were conducted both under high temp. condition(green-house, average temp $25^{\circ}C$-$35^{\circ}C$) and low temp. condition (out-door; average temp $10^{\circ}C$-$25^{\circ}C$) in four plots of 8.10.12 and 14 hours in day length. 3. The results obtained are summarized as follows; i) In the short day condition, the flowering was accelerated in the low temp. than high. On the contrary, in the high temp, it was accelerated in the long day. ii) Generally speaking, the flowering was responsed more in low temp. and short day length than high temp.-long day. iii) But the above trend was found great difference among varieties..-long day. iii) But the above trend was found great difference among varieties.

• Journal of Plant Biology
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• v.19 no.1
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• pp.14-18
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• 1976

Inhibition of flowering in Lemna perpusilla 6746 by 30 mM sucrose was reversed by the addition of acetylcholine (>$10^{-4}M) supplemented with 10^{-4}M$ ascorbic acid to 1/10-strength Hunter's growth medium. The reversible effect of acetylcholine was found to be greater at early stages of flowering than in the later period. Promotive effects of both acetylcholine ($10^{-3}M) and eserine(10^{-5}M$) on flowering in the short-day plant under various photoperiodic conditions were studied. It was indicated that the application decreased length of the critical dark period for the floral induction, and it was also shown that the endogenous status of acetylcholine was involved in the floral response which had a correlation with phytochrome. Interruption of inductive dark periods by red irradiation (1min) immediately followed by far-red light (1 min) completely inhibited flowering, while the addition of acetylcholine and eserine to the medium under the same condition slightly promoted flowering, indicating possible involvement of phytochrome system in acetylcholine activity for photoperiodic sensitivity of floral response in Lemna perpusilla 6746.

• Journal of Plant Biology
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• v.22 no.3
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• pp.81-84
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• 1979

Catalase, glycolate oxidase, hydroxypyruvate and NADPH-glyoxylate reductases activities in cell free extracts from leaves of 3 cultivars, Suwon 264, IR 36 and Jin Heung of rice plants were studied at different growing stages. Catalase and glycolate oxidase shows inclining activities toward the maximum vegetative growth whereas declining activities in either the enzymes were noticed during the maturing stage. After the photoperiodic condition exhibit increasing hydroxypyruvate and NADPH-glyoxylate reductases activities with time until maturing stage. No significant differences were found in the enzyme activities, and in analytical data of nitrogen, chlorophyll contents, dry weight and soluble proteins among the 3 cultivars.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.523-532
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• 1999

The studies were carried out to develop an urban forest aromatic bath in the idle space within city area for handicapped persons, patients and city workers, who having less chance to visit the natural forest aromatic bath. The environmental conditions were checked in the experimental double vinyl house where native and exotic aromatic woody and herbaceous plants were growing with minimum energy input in the periods of mid-winter and mid-summer. The growth and photoperiodic responses of the plants to the low and high temperatures were observed during winter and summer respectively. The most of herbaceous plants in the double vinyl house with the controlled minimum night temperature of $-2^{\circ}C$ had no winter injury but did not grow and started the growth in April. The exotic herbs such as Catnip faassen's(Nepeta x faassenia) and Lemon bergamot(Monarda citriodora) grew better in the longer photoperiodic conditions. The growth rates of Abies koreana, Thuja koraiensis and Pinus sylvestriformis in the early spring were affected mainly by the night minimum temperature and less affected by the photoperiodic conditions during winter. The native aromatic herbs such as Robdosia japonica, Molsa punctulata, Agastache rugosa and Codonopsis lanceolata showed stimulatory growth at the 16 hours day-length in case of the high temperature vinyl hose. The height and root collar diameter growth of pine seedlings were inhibited in maxim temperatures over $40^{\circ}C$ during summer.

• Journal of Sericultural and Entomological Science
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• v.53 no.1
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• pp.1-5
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• 2015

As increasing utilization of Tenebrio molitor for industry, establishing effective conditions of indoor mass-rearing system become more important. For this reason, the aim of this study was to identify the physiological characteristics of Tenebrio molitor in different range of temperatures, photoperiods and rearing densities for mass breeding. As a result, their egg had above 70% hatching rate at $17.5{\sim}27.5^{\circ}C$ and the egg period was shown 5~7 days in $25{\sim}35^{\circ}C$. Consequently, in the consideration of the hatching rates and egg periods, the optimal indoor temperature for rearing was $25{\sim}27.5^{\circ}C$. Furthermore, development period of larvae in mass breeding system was shorter than individual breeding system under all the conditions of temperature. Also, the pupal weight was higher in mass breeding system except for $20^{\circ}C$ and $25^{\circ}C$. Considering elasticity of demand and weight of production, the effective condition was mass-breeding system at $25^{\circ}C$. In photoperiodic condition, the shortest of larval period was 157.35 day in 14L : 10D.

• Nuclear Engineering and Technology
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• v.2 no.3
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• pp.179-183
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• 1970

(4-$^{14}$ C) Cholesterol was administered to the leaves of Solanum andigena during photoperiodic induction. Radioactive products converted from cholesterol were studied by thin-layer chromatography and gas-chromatography. The major products from cholesterol were shown to be esterified cholesterol in lipid and solanine in the aqueous ethanolic phase in SD-and LD-leaves. The radioactive solanidine was isolated by chromatography and crystallized to constant specific activity. Short-day condition did not stimulate the conversion of cholesterol into solanine in the leaves, but both groups of leaves converted cholesterol into solanine at the about same rate. Incorporation of radioactivity into aqueous ethanolic phase of tubers and stolons, containing storied glycoalkaloid, was very much higher than that into lipid phase, contrary to those in the leaves and the stems.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.21-25
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• 2003

The implications of temperature $(25, 30 and 35{\times}1^{\circ}C)$ and relative humidity $(60, 70 and 80{\times}2%)$ on the moulting pattern, moulting duration and moulting survival were studied in the silkworm, Bombyx mori L. Larvae of two pure silkworm breeds, Pure Mysore (PM) and NB$_4$D$_2$and their hybrid, $PM{\times}NB_{4} D_{2}$ were reared under experimental conditions under natural day photoperiodic (LD 12:12) condition. Two developmental marker events in the fourth moulting, settling for moult (SM) and completion of moult (CM) occurred at or around the middle of the photophase. The computed mean vector (equation omitted), based on the circular statistics also confirmed the above. Temperature and humidity did not alter the moulting rhythmicity much. However, extreme temperature and humidity conditions reduced moulting survival in PM and $PM {\times}NB_{4} D_{2}$. Further, moulting survival reduced below the economic level in $NB_{4} D_{2}$. The temperature and humidity together seem to exert synergic impact on the moulting survival of the silkworm Bombyx mori, at least in $NB_{4} D_{2}$.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.80-80
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• 2017

Teosinte is now known as a wild variety of corn. It is distributed in Central and South America. It is believed that teosinte contains genes for resistance to flooding because of the climate characteristics of the collected countries. Recent studies have shown that teosinte has the ability to form adventitious roots, to develop aerenchyma tissues of teosinte, and the resistance to toxic substances under flooding soil condition. Therefore, development of corn cultivars to cope with climate change and the growing corn at paddy field in Korea are required to introduce the characteristics of teosinte. However, in order to utilize teosinte resources, preconditions must be settled such as photoperiodic responsibility. Also if the preconditions are studied together with the metabolic level studies, the possibility of utilization will be even higher.