• Journal of Plant Biotechnology
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• 제50권
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• pp.190-199
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• 2023

Date palm (Phoenix dactylifera L.: Arecaceae) is a dioecious species where only female trees bear fruits. In their natural state, date palms produce dates once a year. However, in Thailand, some trees were observed to produce dates during the off-season, despite no variations in morphology. The availability of such off-season fruits can significantly increase their market value. Interestingly, most female off-season date palms investigated in this study were obtained through micropropagation. Hence, there is an urgent need for genetic markers to distinguish female offseason flowering plantlets within tissue culture systems. In this study, we aimed to develop random amplification of polymorphic DNA-sequence characterized amplified region (RAPD-SCAR) markers for the identification of female off-season flowering date palms cultivated in Thailand. A total of 160 random decamer primers were employed to screen for specific RAPD markers in off-season flowering male and female populations. Out of these, only one primer, OPN-02, generated distinct genomic DNA patterns in female off-season flowering (FOFdp) individuals compared to female seasonal flowering genotypes. Based on the RAPD-specific sequence, specific SCAR primers denoted as FOFdpF and FOFdpR were developed. These SCAR primers amplified a single 517-bp DNA fragment, predominantly found in off-season flowering populations, with an accuracy rate of 60%. These findings underscore the potential of SCAR marker technology for tracking offseason flowering in date palms. Notably, a BLAST analysis revealed a substantial similarity between the SCAR marker sequence and the transcript variant mRNA from Phoenix dactylifera encoding the SET DOMAIN GROUP 40 protein. In Arabidopsis, this protein is involved in the epigenetic regulation of flowering time. The genetic potential of the off-season flowering traits warrants further elucidation.

• Journal of Ecology and Environment
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• 제47권3호
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• pp.134-145
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• 2023

Background: The flowering and fruiting periods play an important role in biological processes. The deciduous dipterocarp forest is an important forest type in Thailand, however the phenological studies are still limited, particularly in different plant life forms. Thus, the present study focused on the flowering and fruiting phenology of herbs, climbers, shrubs, and trees in the deciduous dipterocarp forest at Lampang province of Northern Thailand. Field visits were made to record plant life forms and observe reproductive phenological events at monthly intervals from November 2018 to October 2019 and September to December 2020. Results: The phenological observations were based on 126 species of 45 families and 102 genera. Flowering and fruiting periods showed similar patterns in herbaceous plants, climbers, and shrubs. Most of these species produced flowers and fruits from the end of the rainy season (October) to the winter season (November-January). Whereas most of flowering and fruiting trees were found from the summer season (March-April) to the beginning of the rainy season (May-June). Most of the dry-fruited species occurred during the dry period (winter and summer seasons), while the majority of fleshy-fruited species dominated in the wet period (rainy season). The statistical analysis supported the phenological patterns of flowering and fruiting in the present study. There were significant negative correlations between the number of flowering and fruiting species and temperature. The number of flowering and fruiting species is significantly impacted by the interaction between seasons and plant life forms. Conclusions: Plant life form seems to be the important factor that affects the different phenological patterns in the studied plants. The abiotic and biotic factors play major roles in reproductive phenology. However, long-term study and in-depth phenological observations are necessary for better understanding.

• Journal of Ecology and Environment
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• 제29권4호
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• pp.353-360
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• 2006

Ecological correlates of flowering times often are examined to infer evolutionary mechanisms for flowering time diversities. We examined ecological characteristic associations such as growth habits and pollination modes with flowering times among 3,037 Korean angiosperms experiencing strong climatic seasonalities. We first examined taxonomic membership effects on flowering times across diverse taxonomic levels. Phylogeny constrained flowering times at all levels down to the genus level. We then analyzed the effects of ecological characteristics using subset data consisting of species randomly selected from each genus to control phylogenetic effects. The commonly observed patterns of early flowering of woody species in temperate regions existed. Spring flowering shrubs and trees, however, both being woody, were involved with biotic and abiotic vectors, respectively. In two herbaceous groups of annuals and perennials, annuals flowered later in the growing season than perennials although both herbs tended to be associated with abiotic vectors when flowering in autumn. These results support our hypothesis that species able to decouple vegetative and reproductive growth flower in spring's dry season, but species with different habits, even when they flower within the same season, are subjected to different selective pressures for efficient pollination.

• The Korean Journal of Ecology
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• 제21권5_1호
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• pp.457.2-486
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• 1998

Ecological success of introduced species is frequently attributed to the reproductive characters of those species. We examined the relationship between both flowering season and plant size and reproductive characters in two introduced species of Taraxacum, e.g., T. officinale and T.laevigatum. Seventy six plants of T. officinale and 23 plants of T. laevigatum were randomly tagged from a population at the sungshin Women's University in April of 1997. The size and number of vegetative characters such as rosette diameter, leaf number, and the largest leaf length and width were measured for each plant at the onset of flowering. The infructescence was collected continually from each plant before seed dispersal from April to August of 1997. The number of infructescence per plant, and seed number and total seed weight per infructescence were measured. Mean individual seed weight per infructescence was also obtained. T. officinale possessed larger sized, but smaller number of, leaves than T. laevigatum, thereby resulting in no significant difference in total leaf area. There was a trend that vegetatively larger plants in both of these species produced reproductive characters larger in size or greater in number, except for seed number and total seed weight per infructescence in T. laevigatum. All reproductive characters examined in T. officinale decreased toward the end of flowering season. In T. laevigatum, infructescence number per plant also declined during a flowering season: however, mean seed number per infructescence increaed toward the end of flowering season with no significant seasonal change in the total seed weight per infructescence. T. officinale produced on average about twice as many seeds per plant as T. laevigatum during a growing season. These two Taraxacum species produced quite small seeds in size compared to the endemic species, exhibiting a far better dispersal ability of introduced species. These data demonstrate that most reproductive characters decline in size and number in both species during a long flowering period, but the two species appear to employ different strategies to achieve reproductive success in disturbed habitats.

• 한국자원식물학회지
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• 제14권1호
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• pp.1-7
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• 2001

한라산 백록담내의 고산식물 59종류를 대상으로 생활형, 화색, 개화시기, 그리고 종자의 성숙시기 등을 조사하여 화훼자원으로의 개발가능성을 조사하였다. 백록담내 고산식물의 생활형은 반지중식물이 67.8%로 대부분을 차지하여 전형적인 고산식물의 생활형 분포를 보여주고 있다. 개화는 전반적으로 7∼8월에 이루어지며, 종자는 8∼9월에 집중적으로 성숙되는 것으로 확인되었다. 한편 고산식물의 화색은 백색이 27% (16종)로 가장 많고, 백색, 청색, 황색 꽃의 출현빈도가 대체로 높게 나타났다.

• Animal cells and systems
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• 제2권1호
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• pp.55-63
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• 1998

The effects of inflorescence herbivory and flowering time on plant architecture and reproductive yields were examined with a perennial herbacious species, Vicia cracca, occurring in Natick, Massachusetts, USA. Natural herbivory on inflorescences was observed among the total of 157 plants during a growing season. Vegetative and reproductive characters were measured in the field as well as in the lab depending on the characters. Approximately 64% of the plants were subjected to herbivory on inflorescences. Plants were classified into three groups; unbrowsed plants, partially browsed, and totally browsed plants, according to the level of herbivory on inflorescences of each plant. Plants were also categorized by their flowering time such as early vs late flowering plants. Herbivores tended to favor inflorescences on rather small plants, resulting in a pattern of totally contact or partially intact inflorescences on taller plants. The mean number of stems, which was assumed to be a direct result of severe herbivory in this population, differed among herbivory groups. There also was a tendency that plants flowering late in the season had more nodes with more leaves, suggesting that herbivory on stem tips early in the season before flowering might have induced growth of side branches or branchlets along the main stems. Comparison between unbrowsed and partially browsed plants showed that the latter compensated for browsing in terms of numbers of inflorescences, fruits, seeds and seed size (weight), though they did not compensate in flower number. The probability of fruit production (presence vs absence of fruits) and seed weight declined toward the end of the season. These results suggest that resources are deficient at the end of the season. Almost complete reproductive failure in totally browsed plants is attributed to the destruction of inflorescence display and the disadvantage of small vegetative size of those plants. After all, in this population, a moderate level of herbivory on inflorescences did not reduce the maternal fitness of the plants. However, severe herbivory on inflorescences resulted in antagonistic interactions between plants and herbivores.

• 한국육종학회지
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• 제40권4호
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• pp.439-442
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• 2008

A new spray chrysanthemum cultivar, 'Cherry Blossom' was released by National Horticultural Research Institute (NHRI), Rural Development Administration (RDA), Korea in 2007. A cross was made in 2002 between 'Relance', a spray cultivar with red petals and resistant to white rust and 'Yeonja', a spray cultivar with pink petals. Trials were conducted from 2005 to 2007 for the evaluation and selection of this cultivar, including shading culture in summer and retarding culture in autumn. The natural flowering time of "Cherry Blossom" is late October, but year-round flowering is possible by shading and lighting treatment. This cultivar is single type flowers with dark pink petals and green flower center and resistant to white rust. It is very stable color of petals when the variety is cultivated under high temperature conditions in summer season. The diameter of flower is 55.0 mm. The number of flowers per stem is 10.5 and the number of petals per flower is 24.0. The days to flowering under the short day treatment is about 45 in spring season.

• Natural Product Sciences
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• 제10권5호
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• pp.217-219
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• 2004

Cissus quadrangularis L. variant I (Family: Vitaceae), the common variant with square stem is widely used for peptic ulcer disorders (PUD) in traditional medicine. Aerial parts were collected during flowering and vegetative seasons and analysed. Aqueous (hot and cold) and solvent extracts (acetone, chloroform and ethanol) were screened for their anti-Helicobacter pylori (Hp) activities. Among them chloroform extract was observed to recover bioactive principles markedly with low minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC). MIC was $30\;{\mu}g$ in both samples and MLC was $35\;{\mu}g$ for vegetative and $30\;{\mu}g$ for flowering seasons, respectively. Extracts from samples collected during flowering season were better than thse of vegetative season.

• Current Research on Agriculture and Life Sciences
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• 제31권1호
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• pp.61-64
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• 2013

본 실험은 한국에서 여름철 동안 야간 고온이 스프레이국화의 개화기간에 미치는 영향을 확인하기 위해 수행하였다. 2005년 실험결과에 따르면, 단일기간 중 야간 온도가 $25^{\circ}C$ 이상 지속된 기간은 23.6일로 조사되었고 개화가 지연된 기간은 22일로 조사되었다. 유사한 결과가 2006년에도 조사되었는데, 단일기간 중 야간 온도가 $25^{\circ}C$ 이상 지속된 기간은 23.6일, 개화지연 기간은 23일로 조사되었다. 2007년 결과도 단일기간 중 야간 온도가 $25^{\circ}C$ 이상 지속된 기간은 31.9일, 개화지연 기간은 31일로 조사되었다. 결론적으로 2005년부터 2007년까지의 결과에 따르면, 스프레이국화 'Euro' 품종에서 야간에 고온과 개화기간지연 사이에 특별한 상관관계가 있을 것으로 추정된다.

• The Korean Journal of Ecology
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• 제26권4호
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• pp.181-188
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• 2003

남한산성 지역에서 1999년부터 2000년까지 2년 동안 춘계단명식물의 생육특성을 밝히기 위해 현호색속의 Pes-gallinaceua절에 속하는 집단에서 괴경을 중심으로 생육기 동안 생장특성을 조사 분석하였다. 그 결과 생육초기 괴경에서 지상부의 발생은 토양의 해빙에 따라 일어났으며 토양의 깊이가 깊을수록 지상부의 출현시기가 늦었다. 현호색은 3월 하순에 지상부가 출현하고 5월 초순에 고사하여 총 생육기간은 평균 45일 정도 이었다. 현호색 집단에서 괴경과 총 건중량에 의한 개체의 크기별 빈도는 최소계급이 가장 높았으며(총 건중량에서 40%, 괴경의 건중량에서 53%)중간계급 이하의 빈도는 전체의 93(총 건중량)∼96%(괴경의 건중량)을 나타내 작은 개체가 대부분을 차지하는 개체군으로 나타났다. 괴경은 생육초기 지상부가 출현하여 일이 완전히 전개되기 전까지 비중이 0.14까지 감소하였다가 생육기 말 종자가 결실하고 지상부가 고사하는 시기에 0.42까지 증가하였다가 이 후에 다시 서서히 감소하였다. 한편, 생식기관이 있는 것은 없는 것에 비하여 생육기간 동안 괴경의 비중이 낮았으며 1% 이하에서 유의한 차이를 보였다. 생육기말 괴경의 부피에 따른 괴경의 비중은 감소하였고 엽면적은 대체로 증가하였으나 경향성이 뚜렷하지 않았으며 지상부/지하부의 비율은 일정한 경향성이 없었다. 한편, 괴경의 건중량이 증가할수록 괴경의 비중은 감소하였고 엽면적은 증가하였으며 증가 혹은 감소하는 경향성은 뚜렷하였다. 작은 개체일수록 괴경에 많은 양의 에너지를 축적하였으며 지상부/지하부의 비율은 개체마다 다양한 것으로 나타났다.