• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.395-400
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• 2001

We investigated the variations of the flowering response to daylength in Perilla crop (var. frutescens). Seventeen accessions of Perilla crop and one accession of weedy type of var. crispa from China, Korea and Japan were cultivated under three daylength conditions, i.e., short-days, natural daylength and long-days. Most accessions of Perilla crop from China, Korea and Japan were divided into three types, early maturing type, intermediate maturing type and late maturing type by their natural flowering habit. In most of the accessions used, the flowering habit was significantly accelerated by short-day conditions and was delayed by long-day conditions. All the accessions of Perilla crops flowered within 57 days under the 10 hrs light treatment, whereas they did not flower at all even at 170 days after sowing under the 16 hrs light treatment. Thus, this finding suggested that there is a relationship between the types of flowering response to daylength and the geographical distribution which determines the planting season in traditional cultivation practices of Perilla crops. Positive correlation was observed between days to flowering and plant height or internode number in both the short-day and natural daylength conditions. Whereas, correlation was negative between days to flowering and inflorescence length or floret number in natural daylength condition, but it was positive in the short-day condition. Therefore, the daylength condition is considered as the most important environmental factor for flowering habit and morphological characters of Perilla crops. Flowering habit is considered as an important key character for the study of geographical differentiation of Perilla crop in East Asia.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.330-335
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• 1993

Sesame cultivars were treated with temperature and daylength to determine the environmental variance of Antioxidant content The experiment was performed in phytotron with 11, 13, 15hours of daylength and 20/15, 25 120, 30/25$^{\circ}C (day / night) of temperature treatment. Varietal differences of antioxidant content were significant by the temperature and daylength treatment. Antioxidant content was incrased at higher temperature(25/2$0^{\circ}C$, 30/25$^{\circ}C) and daylength(13hours) but decreased at lower temperature (20/15$^{\circ}C), short daylength (l1hours) and long day length (15hours) condition. Sesamin content were showed 0.06% difference as maxium by the temperature treatment, while 0.03% by the daylength treatment. Sesamolin content were showed 0.03% difference as maxium by the temperature treatment, while 0.01% by the daylength treatment. The antioxidant content was influenced by the increased temperature than daylength.

• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.136-146
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• 1993

In order to study flowering of Chrysanthemum coronarium, several investigations on the daylength, shading, irrigation and plant growth regulator treatment were carried out. As daylength was treated for 12, 14 and 16hrs, flowering was accelerated and plant height was increased. Leaf number, length and width were decreased by the increased daylength. Sensitivity to daylength and flower development were accompanied by the plant growth, especially the effect of long day treatment was appeared remarkably when the number of leaves was more than 8 leaves. The minimum days of long day treatment for flowering was more than 10 days. Flowering was delayed by 65% shading treatment, over irrigation.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.127-134
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• 1989

Several growth characteristics of two ornamental tobacco species, Nicotiana sanderae and N. affinis, were investigated in this study. Also effect of temperature and daylength on the flowering of the tobacco plants were evaluated to obtain basic information on breeding and cultivation. 1. The plants were great in high temperature-long day at the early stage and in low temperature-short day at the late stage of plant growth, for both Nicotana species. At the early growth stage the leaf length N. sanderae was great in high temperature-long day, and that of N. affinis was great in high temperature-short day period, while at the late stage of the plant growth the leaf lengths were more significantly effected by the temperature rather than daylength. Leaf width and leaf shape index were less sensitive to the conditions. 2. For both of the species, the total number of tobacco leaves not much influenced by the temperature and daylength. 3. There were no significant differences for budding and flowering period between the two species, both of which were sensitive to temperature and daylength with more influence by daylength than temperature. 4. Number of floral stalks, number of flower and flowering period were not much influenced by temperature and daylength; however, N. affinis had 2 more floral stalks, 31 more flowers, and 6 day longer flowering period than N. sanderae.

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.114-117
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• 2005

Orostachys japonicus, called Wasong as herbal medicine and a short day plant, should be artificially kept in long daylength to control anthesis of its florets. The study was done to clarify the effect of daylength (10, 13, 16 hours a day) on growth, morphological characters, and flowering. The treatments were done on August 25 and afterward samples were taken every 2 weeks. Growth, morphological and flowering related characters were measured from each sample. With longer daylength plant height and inflorescence length were increased but number of leaves including bracts and stem diameter were decreased. Leaves and bracts, stem, root, shoot and total dry weights were increased with longer daylength from late September while floret dry weight showed reverse result. Florets formed were the greatest in daylength of 10 hours during September but the least during the other period. Anthesis of the florets was observed only in daylength of 10 hours during October and all the plants from the treatment were flowered.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.195-201
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• 2001

Sowing date experiments were carried out by employing a rice variety "Kwanganbyeo" in both field and phytotron with natural daylength. In phytotron, temperatures were controlled at daily mean of 21$^{\circ}C$ and 24$^{\circ}C$. The responses of final leaf number and beading date were analyzed in relation to daylength during photo-sensitive period (PSP). Based on the component models predicting the final leaf number and leaf appearance rate, a rice phenology model was established and verified. Days from sowing to flowering (DSF) were shortened and final number of leaves (FNL) increased as sowing dates were delayed from 25 April to 5 June in field and phytotron. The increased leaf appearance rate (LAR) and the reduced FNL, respectively, due to the higher temperature and the shorter daylength in delayed sowings in the field brought about greater shortening of DSF than in the phytotron where only FNL was reduced by shorter daylength in delayed sewings. FNL showed very close relationship with the average daylength during PSP of six-leaf stage to panicle initiation, being well fitted to the following rational function ($R^2$=0.98):(equation omitted) where D is daylength and a, b, and c are the constants that were estimated as 14.694, -0.992, and -0.068 in Kwanganbyeo, respectively. The rice phonology model, which was composed of two component models for LAR and FNL, predicted DSF very accurately. The differences between the observed and predicted DSF was less than two days in the sewing date field experiments in 1999 and 2000 of which data were not used for the model construction.struction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.121-124
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• 1981

The panicle enclosing Gamadi rice cultivar from western Tarai of Nepal was treated with different daylengths; 8 hours, natural daylength i.e. 14 hours 30 minutes to 12 hours 30 minutes, and 24 hours throughout its life cycle. The extremely long daylength of 24 hours induced the panicle exsertion, and elongated the first internode from the top, but did not affect the second internode significantly, suggesting that the panicle exsertion was strongly correlated with the first internode elongation in the Gamadi rice cultivar.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.20-25
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• 1994

This study was carried out to investigate the effect of temperature and daylength on the bolting of Angelica gigas Nakai for decreasing the rate of bolting.Seedlings were transplanted on early December to the PVC pot(1 /1000) in the greenhouse con­trolled the temperature of 15, 20 and $25^{\circ}C$, and the daylength of 8, 12, and 16hrs. Growth of aerial parts, bolting rate and root characteristics of A. gigas were investigated. Seedlings of A. gigas untreated with low temperature were nomally emerged, bolted and flowered in maturing stage. In this results, it was assumed that A. gigas was low sensitive to low temperature. The early growth stage was good at $20^{\circ}C\;and\;25^{\circ}C$, but the late growth was effective at $15^{\circ}C\;and\;20^{\circ}C$. The bolting rate was the highest at $20^{\circ}C$ while the root weight was the lowest. Although the bolting rate was high at $15^{\circ}C$, the yield was increased by the delay of bolting and flowering stage. The bolting rate was increased in the longer daylength and showed more sensitive to the daylength condition than to the temperature. Thus, A. gigas cultivated in gully field with cool temperature or under the shading light could be reduced could the bolting rate.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.751-754
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• 1998

Heterophil (H) to lymphocyte (L) ratios and durations of tonic immobility (TI) were measured to assess stress and fear responses, respectively, in broiler chickens provided either 12 h of natural lighting (12L) or 12 h natural lighting and 12 h of supplementary lighting (24L). Birds illuminated 24L had greater H/L ratios and TI durations than their 12L counterparts. Neither age, sex nor cage level had significant effect on TI reactions.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.11a
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• pp.49-49
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• 2020