• 한국농림기상학회지
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• 제5권3호
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• pp.208-212
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• 2003

가로등과 보안등의 증가로 인한 야간조명의 확대와 야간 이동차량의 증가로 전조등 등 농경지 주변에 간헐적으로 조명이 이루어지고 있어 2000년부터 2001년까지 2년 동안 암기간과 야간조파가 벼와 콩의 출수 및 개화에 미치는 영향을 구명하고자 수행한 시험결과를 요약하면 다음과 같다. 12시간 암기 중 3시간마다 10분간 백열등(50∼60 lux)으로 조명한 야간조파 처리에 의하여 벼 생육은 두 품종 모두 암기처리 12시간에 비해 간장은 증가되었으며, 수당립수는 감소되었다. 벼의 출수는 야간조파시 암기처리 12시간에 비하여 일품벼 9일, 화성벼는 26일 지연되었으며, 12시간의 암기처리에 비하여 9시간 암기처리시 일품벼 47일, 화성벼는 41일 지연되었다. 야간조파에 의한 황금콩의 생육은 야간조파시 암기처리 12시간에 비해 경장파 절수가 증가되었으며, 협수는 감소되었고, 12시간의 암기처리에 비하여 9시간 암기처리시 경장 및 절수는 증가되었지만 협수는 감소되었다. 콩의 개화까지 소요일수는 야간조파시 암기처리 12시간에 비하여 4일 지연되었으며, 12시간의 암기처리에 비해 9시간 암기처리시 19일 지연되었다.

• Journal of Plant Biology
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• 제27권4호
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• pp.215-222
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• 1984

The reversal effect of salicylic acid(SA) on inhibition of flowering in Lemna gibba $G_3$ grown on ${NH_4}^+$-free 1/2H medium under continuous light is modified by ${PO_4}^{2-}$- and $Ca^{2+}$ levels. Dimethylsulfoxide(DMSO) either depresses the SA effect in ${NH_4}^{1}$-free 1/2H medium or amplifies it in E medium. The dual action of DMSO determined by relative levels of macro and micronutrient components is discussed.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.27-39
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• 2005

a-Ketol linolenic acid [KODA, 9,10-ketol-octadecadienoic acid, or 9-hydroxy-10 -oxo-12(Z), 15(Z)-octadecadienoic acid] was found as a stress-induced factor in Lemna paucicostata. KODA reacts with catecholamines to generate many products that strongly induce flowering in L. paucicostata, although KODA itself was inactive. KODA contains an asymmetric carbon at the 9-position in the molecule; the 9-hydroxyl group is predominantly 9R, with an enantiomeric excess of 40% (70% 9R and 30% 9S). We analyzed two major products of the reaction between KODA and norepinephrine, named FN1 and FN2. FN1 was identified as a tricyclic a-ketol fatty acid, 9(R)-11-{(2'R,8’R,10'S,11'S)-2',8'-dihydroxy-7'-oxo-11'-[(Z)-2-pentenyl]-9'-oxa-4'-azatricyclo[6.3.1.01.5]dodec-5'en-10'-yl}-9-hydroxy-10-oxoundecanoic acid. FN2 was the C-9 epimer of FN1. FN1 was derived from 9R-type KODA and FN2 from 9S-type. FN1 showed strong flower-inducing activity, but FN2 was inactive. Pharbitis nil (violet) is a typical short-day plant; flowering can be induced by exposing a seedling cultivated under continuous light to a single 16-h dark period. We analyzed endogenous KODA levels and showed that they were closely related to flower induction: KODA sharply increased in the later part of a 16-h dark period, on the other hand, it failed to increase in the night-break experiment. In addition to it, KODA increased transiently in immature flower buds in all the plants we examined, including P. nil. No such increase of KODA was seen in foliar buds of P. nil. When KODA was sprayed on seedlings of Pharbitis, flower induction was promoted only by the (R)-form of KODA. We also found that KODA enhances flowering in garden plants such as carnations and impatienses. These phenomena indicate that KODA may be involved in flowering formationg of plants and it is potentially useful for a regulating agent for commercial plant flowering.

• 대한원격탐사학회지
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• 제38권1호
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• pp.57-72
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• 2022

In this paper, we aimed to examine the flowering dates of cherry blossom and the peak dates of maple leaves in South Korea, by the combination of temperature observation data from ASOS (Automated Surface Observing System) and NDVI (Normalized Difference Vegetation Index) from MODIS (Moderate Resolution Imaging Spectroradiometer). The more recent years, the faster the flowering dates and the slower the peak dates. This is because of the impacts of climate change with the increase of air temperature in South Korea. By reflecting the climate change, our statistical models could reasonably predict the plant phenology with the CC (Correlation Coefficient) of 0.870 and the MAE (Mean Absolute Error) of 3.3 days for the flowering dates of cherry blossom, and the CC of 0.805 and the MAE of 3.8 for the peak dates of maple leaves. We could suppose a linear relationship between the plant phenology DOY (day of year) and the environmental factors like temperature and NDVI, which should be inspected in more detail. We found that the flowering date of cherry blossom was closely related to the monthly mean temperature of February and March, and the peak date of maple leaves was much associated with the accumulated temperature. Amore sophisticated future work will be required to examine the plant phenology using higher-resolution satellite images and additional meteorological variables like the diurnal temperature range sensitive to plant phenology. Using meteorological grid can help produce the spatially continuous raster maps for plant phenology.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.51-51
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• 2022

Water dropwort (Oenanthe stolonifera DC.) is a perennial herbaceous plant that grows wild throughout Korea. As of 2020, 24,819 tons (51.7% of open field, 48.3% of facility) are produced in 1,278 ha (59.9% of open field, 40.1% of facility) nationwide. Water dropwort, which is rich in nutrients such as vitamins and iron, is mainly cultivated by vegetative propagation method using local traditional species, however, seed propagation and breeding of cultivars are insufficient so far. Since securing, propagating and continuous characterization of various genetic resources are required to breed new cultivars, this study was conducted to compare the main characteristics of domestic genetic resources and to improve their utilization. Growth characteristics such as plant height, fresh weight, plant type, and flowering date were investigated for the 89 varieties of genetic resources owned by Jeollabuk-do Agricultural Research and Extension Services after vegetative propagation in the individual pots. Also, the morphological image information of leaves and flowers was constructed. Genetic resources were collected nationwide and originated in 30 regions including Hwaseong, Siheung and Jeju. Their plant types could be classified into straight, intermediate and creeping types according to their morphological characteristics, and at this time, the number of intermediate types accounted for the largest proportion. Flowering was carried out under high-temperature and long-day conditions in summer. According to the flowering date, they could be classified into early, middle and late flowering varieties, and at this time, the middle flowering varieties occupied the largest proportion. As a result of the investigation of vegetative growth characteristics, varieties with long plant height, heavy fresh weight and thick stem thickness were identified. Along with this result, it is thought that classification and selection of genetic resources for various purposes will be possible through additional investigations such as analysis of components and antioxidant activity. Moreover, it is judged that such results can be used as basic data for breeding new water dropwort cultivars in the future.

• Journal of Plant Biology
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• 제35권4호
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• pp.403-408
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• 1992

장일식물인 Lemna gibba G3의 개화유도과정에 있어서 polyamine의 관련성을 조사하였다. 이 식물의 개화는 연속광하에서 agmatine, putrescine, spermidine 및 spermine에 의해 촉진되었으며 이들의 체내 합성억제물질인 methylglyoxal-bis(guanylhydrazone)(MGBG)과 cyclohexylamine(CHA)에 의해서 억제되었다. Polyamine은 영양생장률을 거의 일정한 수준으로 유지하면서 개화를 촉진시켰으며, 억제물질에 의한 개화억제는 오히려 영양생장률의 증가를 수반하였다. 이러한 현상은 이 물질들의 개화촉진 또는 억제효과가 생장률의 일반적인 촉진 또는 억제효과에 의한 것이 아니라 선택적으로 개화과정에 작용한 결과일 것이라는 추측을 뒷받침해 준다. 배양액의 첨가된 spermidine 또는 spermine의 개화촉진 폭은 배양액에 이들의 억제물질의 함유여부와 관계없이 거의 일정한 수준으로 나타났다. 이렇듯, 외부에서 공급된 후 체내에 흡수된 spermidine과 spermine의 개화에 대한 기여도가 한정되어 있는 것으로 보아 L. gibba G3의 개화유도과정이 식물체내에서 합성되는 spermidine과 spermine에 크게 의존하고 있을 것으로 판단된다. 한편, 개화유도과정이 시작되어 점차적으로 증가한 체내의 spermidine 함량은 개화가 유도되지 않은 경우에 비하여 24시간만에 약 2배의 수준에 도달하였다. 이렇듯 체내의 spermidine량이 급격히 증가된 사실은 체내의 polyamine의 질적 및 양적 변화가 L. gibba G3의 개화유도초기과정에서 매우 중요한 역할을 하고 있을 것이라는 가정을 뒷받침하는 또 하나의 예비적 증거라 할 수 있다.

• Journal of Forest and Environmental Science
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• 제32권4호
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• pp.353-366
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• 2016

The effect of different environmental conditions and altitudes on the growth and reproductive characteristics in 12 teak plantations at 4 different blocks (Cauvery canal bank, Topslip and Parambikulam (Tamil Nadu), Nilambur and Wayanad (Kerala) of Southern India was investigated. The annual rainfall and mean monthly temperature of the study areas varied significantly from 1390 to 3188 mm and 16 to $38^{\circ}C$ respectively. The teak plantations in Cauvery canal bank which grow in continuous moisture condition (8-10 months) retain the leaf for longer period due to moisture resulting continuous supply of photosynthates leads to fast and outstanding growth. The girth at breast height (GBH) of 34-years-old tree in canal area was similar to that of 40 to 49-years-old trees in other locations, indicating that teak plantations with regular watering and silvicultural practices may be harvested at the age of 30 years. The leaf fall, flowering and fruiting showed significant variations in different teak plantations due to environmental factors and altitudes. It was found that increase of rainfall enhances number of flowers in the inflorescence in teak. Tholpatty (block-IV) showed more flowering in a inflorescence (3,734-3,744) compared to other plantations (1,678-3,307). Flowering in Nilambur and Wayanad coincided with heavy rainfall resulting low fruitset (1.1-2.3%) probably heavy rainfall ensuing restriction of pollinators for effective pollination. On the other hand, flowering in Cauvery canal bank (Block-I) was not coincided with high rainfall exhibited high fruitset (2-3%). About 66 to 76% of the fruits in different plantations were empty, and it is one of the main reasons for poor germination in teak. The seeds of Topslip and Parambikulam (Block-II) showed higher seed weight, maximum seed filling and good germination indicating that the environmental factors and altitude play significant role in fruit setting and seed filling in teak. In addition, the teak plantations in Topslip and Parambikulam showed good growth suggesting that plantations in the altitude range of approximately 550-700 m may be suitable for converting into seed production areas for production of quality seeds.

• 식물분류학회지
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• 제48권3호
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• pp.218-229
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• 2018

Myanmar's plant diversity is expected to be very high given the wide variety of climates and the diverse vegetation and geographical features of the country. Since the publication of Kress et al.'s plant checklist in 2003, new and unrecorded species have been constantly reported by various botanists, but much of Myanmar's flora requires more intensive examinations. We conducted joint floristic surveys of several Ywangan areas, including the Panlaung-Pyadalin Cave Wildlife Sanctuary in southern Shan State of Myanmar. The initial identification of seed plant specimens collected from three short floristic expeditions revealed that 23 species were newly recorded species in Myanmar. More than half of these were found to be geographically notable species, which are known to be endemic to neighboring countries such as China (4 spp.), Thailand (6 spp.), and India (2 spp.). A considerable number of these unrecorded species are distributed in the limestone areas of neighboring countries, reflecting the geological characteristics of the survey area. The results of this study reemphasize the need for intensive and continuous research on the flora of Myanmar for a more comprehensive understanding of the distribution patterns of flowering plants in Southeast Asia.

• Ocean and Polar Research
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• 제26권1호
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• pp.23-32
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• 2004

As a baseline survey for long-term monitoring on environmental change around the Antarctic King Sejong Station, distribution pattern of Deschampsia antarctica Desv., a flowering plant newly colonized were investigated qualitatively and quantitatively in both austral summer 2002 and 2003. Dispersal of the seeds and vegetative leaves by skuas might lead to the colonization into this area from neighbors in Maxwell Bay. The pioneer populations were observed around ponds and a stream of the Sejong Point in January 2002, and the maximum dispersal area was four times expanded after a year. Most of the populations were formed on the stable and well-drained substrate, which consisted of moss carpet of Sanionia georgico-uncinata (65%) and pebbles (25%), while only a few young individuals were observed on the unstable and watertight silt-sandy area. Especially, S. georgico-uncinata was being effectively utilized as their primary substrate with the soft, coarse and water-contained leaves. Also the perennial mature plants of D. antarctica were mainly formed on the moss carpet rather than pebbles. A few individuals were grown on other mosses of Polytrichastrum alpinum, Bryum pseudotriquetrum, Pohlia cruda, and Conostomum magellanicum and on a liverwort of Cephaloziella varians. We expect that dispersal of D. antarctica and the following succession to grass field will be countinuously and dynamically proceeded in this area, with the characteristics of ecological niche against the initial moss populations, on the similar continuity of environmental conditions. The continuous observations are needed with establishment of database on environmental change of micro-habitats, e.g. the water content and nutrients of soil and the underground temperature and permafrost.

• Journal of Ecology and Environment
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• 제34권4호
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• pp.371-379
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• 2011

To determine the peak dispersal times of allergenic pollen grains in Ulsan, Korea, we performed continuous airborne pollen counts at three stations (Sts. A, B, and C) in Ulsan from August 2009 to November 2010. Pollen grains were sampled using a Durham sampler. Two peak pollen dispersal seasons were observed per year. The peak seasons generally coincided with the flowering period of anemophilous trees: Taxodiaceae (February), Alnus (March), Cupressaceae (April), Quercus, and Pinus (May), and with the flowering phase of herbs from August to November, e.g., Humulus, Artemisia, Gramineae, and Ambrosia from August through September. The highest concentration of airborne pollen was from Pinus (68%), followed by Quercus (15%), Alnus (6%), and Humulus (2%); whereas very low pollen concentrations were from Taxodiaceae, Cupressaceae, Artemisia, Gramineae, and Ambrosia (${\leq}$ 1% of the annual total airborne pollen concentration). Our findings indicate that Alnus and Humulus pollen are major allergens whereas those of Pinus and Quercus are minor allergens. The concentration of Alnus pollen grains at St. C was over five times that at Sts. A and B. This finding implies that individuals living at or near St. C are exposed to high concentrations of Alnus pollen before and after March, which is the flowering period of the alder tree. From August to September, individuals living at or near St. B are exposed to high concentrations of Humulus pollen. Our study suggests that Alnus pollen may be the major aeroallergen causing pollinosis in the spring at St. C and Humulus pollen may be the major aeroallergen in autumn at St. B.