• 제목/요약/키워드: temperate region

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제주지역에 도입된 편백의 가계별 생장특성과 유전력 구명 (Growth and Heritability of Hinoki Cypress (Chamaecyparis obtusa) Families in Jeju)

  • 최형순;강영제;김인식;박영규;유근옥
    • 한국농림기상학회지
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    • 제14권4호
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    • pp.236-245
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    • 2012
  • 제주지역에 도입된 편백 18가계의 초기 생장부터 현재(42년생) 까지의 연령별 수고, 흉고직경, 재적생장을 분석하였다. Yako-7, Muei-1, Sangsong-9 가계가 우수한 생장을 하였으며, Sangeun-3, Yago-6, Hyena-2 가계의 생장이 저조한 것으로 나타났다. 연령별 평균생장을 분석한 결과, 수고생장은 9년생에서 15년생 사이의 생장이 다른 연령대에 비해 우수하였으며, 흉고직경의 생장은 특별한 경향이 관찰되지 않았다. 수고, 흉고직경, 재적의 가계유전력은 각각 0.68, 0.75, 0.75로 추정되었으며, 연령간의 생장을 비교한 결과, 유노상관 관계는 없는 것으로 판명되었다.

난대 기후대의 상록활엽수림 복원 모니터링(II) (Monitoring for the Restoration of Evergreen Broad-leaved forest in Warm Temperate Region(II))

  • 오구균;최송현;나경태;김성현
    • 한국환경생태학회지
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    • 제17권4호
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    • pp.316-323
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    • 2004
  • 상록활엽수림을 목표로 한 식생복원시험을 모니터링하기 위하여 1996년 전라남도 완도수목원에 밀도조절, 택벌, 상록활엽수종 식재 등 상록활엽수 복원처리를 한 시험구와 대조구를 포함하여 18개 고정 시험구를 설치했다. 식생복원시험 처리 후 7년 경과시 붉가시나무군락의 시험구는 대조구에 비하여 붉가시나무의 상대우점치가 높아지는 경향이 나타났고, 붉가시나무-개서어나무군락의 시험구에서는 교목층의 붉가시나무의 상대우점치가 크게 증가했으며, 소나무군락의 시험구에서는 붉가시나무의 상대우점치가 증가하였다 상록활엽수 복원시험구의 산림식생은 붉가시나무군락으로 식생천이가 촉진되거나 성숙되고 있었다. 또한 시험처리 후 7년 동안 상록활엽수림 복원시험구에서 상록활엽수의 상대우점치와 난대수종 수, 흉고단면적이 대조구보다 증가한 반면 이식한 상록활엽수목들의 수세는 쇠퇴하였다.

Granule-Bound Starch Synthase I (GBSSI): An Evolutionary Perspective and Haplotype Diversification in Rice Cultivars

  • Sang-Ho Chu;Gi Whan Baek;Yong-Jin Park
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.219-219
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    • 2022
  • Granule-bound starch synthase I (GBSSI), encoded by the waxy gene, is responsible for the accumulation of amylose during the development of starch granules in rice endosperm. Despite many findings on waxy alleles, the genetic diversity and evolutionary studies are still not fully explored regarding their functional effects. Comprehensive evolutionary analyses were performed to investigate the genetic variations and relatedness of the GBSSI gene in 374 rice accessions composed of 54 wild accessions and 320 bred cultivars (temperate japonica, tropical japonica, indica, aus, aromatic, and admixture). GBSS1 coding regions were analyzed from a VCF file retrieved from whole-genome resequencing data, and eight haplotypes were identified in the GBSSI coding region of 320 bred cultivars. The genetic diversity indices revealed the most negative Tajima's D value in the tropical-japonica, followed by the aus and temperate-japonica, while Tajima's D values in indica were positive, indicating balancing selection. Diversity reduction was noticed in temperate japonica (0.0003) compared to the highest one (wild, 0.0044), illustrating their higher genetic differentiation by FST-value (0.604). The most positive Tajima's D value was observed in indica (0.5224), indicating the GBSSI gene domestication signature under balancing selection. In contrast, the lowest and negative Tajima's D value was found in tropical japonica (-0.5291), which might have experienced a positive selection and purified due to the excess of rare alleles. Overall, our study offers insights into haplotype diversity and evolutionary fingerprints of GBSSI. It ako provides genomic information to increase the starch content of cooked rice.

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한국산 미기록 식물 : 성널수국 (수국과) (An unrecorded species in Korean flora : Hydrangea luteovenosa Koidz. (Hydrangeaceae))

  • 문명옥;강영제;김철환;김찬수
    • 식물분류학회지
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    • 제34권1호
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    • pp.1-7
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    • 2004
  • 국내 미기록종인 수국과 (Hydrangeaceae)의 성널수국 (Hydrangea luteovenosa Koidz.)을 제주도 한라산의 성널오름 지역에서 채집하였다. 본 분류군은 습성, 잎의 길이와 폭, 엽병의 길이, 양성화의 꽃잎과 거치의 형태, 자방의 위치, 측맥과 수술의 수의 특정에 의해 한국산 산수국 [Hydrangea serrata (Thunb.) Ser.]과 등수국 [H. petiolaris Siebold & Zucc.]과 뚜렷하게 구별되었다.

Phenological Studies of Deciduous Trees in the Cool Temperate Region of Japan

  • Jun, Kala;Hayashi, Ichiroku
    • Journal of Ecology and Environment
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    • 제31권3호
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    • pp.193-200
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    • 2008
  • We obtained quantitative information on leaf unfolding and leaf shedding by observing 45 species of cool temperate deciduous trees in an arboretum over 5 growing seasons. These trees were in leaf (the foliage period) for 207 days on average after 1 April; 50% of leaves had been shed by 192 days after 1 April. Duration from the start of leaf unfolding to 50% leaf shedding was 157 days on average. Leaf unfolding began 35 days on average after 1 April. For leaf unfolding to begin, a$ 51^{\circ}C{\cdot}day$ of cumulated daily mean air temperature above $5^{\circ}C$ from 1 January (modified Kira's warmth index) was needed. Fifty-nine days elapsed between initiation and the final stage of leaf unfolding. The period of net photosynthetic assimilation was 157 days. The species with succeeding- type leaf unfolding associated with the anemochore seed type dominated the early stage of succession, while the species with flush-type leaf unfolding tended to dominate the late stage of succession. Few species were found in regions where late frosts occur after the day when the cumulative temperature for leaf unfolding is achieved. Biological characteristics include time of leaf unfolding, which affects the life history of each species, so that each species occupies its own niche in the stand. We conclude that that leaf phenology, such as timing of leaf unfolding and leaf shedding, is one of the components of each species' ecological characteristics.

Stable Nitrogen Isotopes in a Forested Watershed in Taiwan

  • Owen, Jeffrey S.
    • Journal of Forest and Environmental Science
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    • 제29권2호
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    • pp.116-124
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    • 2013
  • Differences in rates and patterns of nitrogen cycling have been correlated with nitrogen stable isotope measurements in forest ecosystems of tropical and temperate regions, but limited similar work has been conducted in sub-tropical forests. This study investigated patterns in stable N isotopic composition in a subtropical forest in Taiwan by sampling three soil profiles and overstory and understory foliage. Soil ${\delta}^{15}N$ in the forest floor ranged from -1.8 to -1.8‰. Mineral soils had higher ${\delta}^{15}N$ (4.1 to 6.0‰). Foliage ${\delta}^{15}N$ in overstory trees ranged from -6.6 to -2.0‰, and understory foliage ${\delta}^{15}N$ ranged from -5.0 to -1.2‰. There was a weak correlation between foliar % N and ${\delta}^{15}N$ ($r^2=0.214$). Compared to results from similar surveys in tropical and temperate forests, foliar ${\delta}^{15}N$ values were generally lower. These results help highlight the need for improved knowledge regarding the relationships between patterns in N stable isotopes and processes affecting rates of N cycling, especially as related to wider scale patterns in forest ecosystems within the east-Asia region.

Species Composition and Diversity in Mid-altitudinal Moist Temperate Forests of the Western Himalaya

  • Gairola, Sumeet;Sharma, C.M.;Suyal, Sarvesh;Ghildiya, S.K.
    • Journal of Forest and Environmental Science
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    • 제27권1호
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    • pp.1-15
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    • 2011
  • The present study was undertaken in middle altitudinal (1500 to 2500 masl) moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to assess the variation in species composition and diversity in different vegetation layers viz. herb, shrub and tree, at different altitudes. Shannon-Wiener diversity index ($\bar{H}$), $Nha^{-1}$, total basal cover per hectare (G), Simpson concentration of dominance, Pielou Equitability, species richness (SR), Margalef index, Menheink index of species richness and ${\beta}$-diversity were calculated to understand community composition. Tree G ranged from 84.25 to 35.08 $m^2ha^{-1}$ and total stem density varied from 990 to 1470 Nha-1. Total SR (herb, shrub and trees) among different forest types ranged between 31 and 58. Maximum G of herb and shrub layers was recorded at lower altitudes between 1500 and 1650 masl. ${\beta}$-diversity was higher in herb layers as compared to tree and shrub layers. Dominance-diversity curves were also drawn to ascertain resource apportionment among various species in different forest types. Values of species diversity, $\bar{H}$, $Nha^{-1}$ and G were higher in the study area as compared to similar forests growing in other parts of Uttarakhand Himalaya.

Characterization of PUL Haplotypes and Its Evolutionary Analyses in Korean Rice Accessions

  • Thant Zin Maung;Yong-Jin Park
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.217-217
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    • 2022
  • Pullulanase (PUL), a debranching enzyme, has been utilized in hydrolyzing the a-1,6 glucosidic linkages in starch, amylopectin, pullulan, as well as related oligosaccharides. It has also been indicated that PUL is a novel indicator of inherent RS (Resistant Starch) formation in rice. In this study, we performed haplotype analysis on 320 bred rice accessions, and additional 54 wild accessions were added to study genetic diversity along with other population-based analyses of the PUL gene. Through these investigations, we summarized a total of 10 functional (non-synonymous) SNPs from 7 different exons on chromosome 4. There were 10 haplotypes, of which only six haplotypes were functional, implicating different subpopulations. Diversity reduction was noticed in temperate japonica (0.0005) compared to the highest one (aus, 0.0154), illustrating their higher genetic differentiation by FST-value (0.926). The highest Tajima^ D value was observed in indica (3.6613), indicating PUL gene domestication signature under balancing selection, while the lowest Tajima's D value was found in temperate japonica (-2.2191) which might have undergone under positive selection and purified due to the excess of rare alleles. PCA, population structure, and phylogenetic analyses provide information on the genetic relatedness between and or among the cultivated subpopulations and the wild based on PUL genomic region.

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Monthly variations in semen parameters in a Sri Lankan population undergoing fertility evaluation

  • Anura Dissanayake
    • Clinical and Experimental Reproductive Medicine
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    • 제51권2호
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    • pp.120-124
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    • 2024
  • Objective: Seasonal variations in semen quality are known to occur in temperate regions, but results regarding tropical areas remain inconclusive. The aim of this study was to determine whether monthly variations in semen parameters are present among men in a tropical region. Methods: Data were retrospectively collected from semen analyses of 3,000 men over a 10-year period, from 2012 to 2022. Analysis of variance and the independent-samples t-test were employed to observe variations in semen parameters throughout the entire period and between months, respectively. Results: The mean±standard deviation sperm concentration was significantly lower in June, at 42.5±31.4 million/mL, compared to other months. The highest sperm concentration was found in March, at 57.8±42.6 million/mL, constituting a mean difference of 15.3 million/mL between the lowest and highest concentrations. The total sperm count displayed a similar pattern of monthly variation, with a difference of 47.2 million between the highest and lowest months. No significant monthly differences were observed in other parameters, such as sperm motility, morphology, and semen volume. Conclusion: Significant monthly variations in sperm concentration and total sperm count were evident in this Sri Lankan population. March, which displayed the highest sperm counts, is in the spring in temperate regions, while the month with the lowest counts, July, is part of the summer. Fluctuations in photoperiod appear to most strongly influence these variations.

Purification and Characterization of Repressor of Temperate S. aureus Phage Φ11

  • Das, Malabika;Ganguly, Tridib;Chattoraj, Partho;Chanda, Palas Kumar;Bandhu, Amitava;Lee, Chia Yen;Sau, Subrata
    • BMB Reports
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    • 제40권5호
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    • pp.740-748
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    • 2007
  • To gain insight into the structure and function of repressor proteins of bacteriophages of gram-positive bacteria, repressor of temperate Staphylococcus aureus phage ${\phi}11$ was undertaken as a model system here and purified as an N-terminal histidine-tagged variant (His-CI) by affinity chromatography. A ~19 kDa protein copurified with intact His-CI (~ 30 kDa) at low level was resulted most possibly due to partial cleavage at its Ala-Gly site. At ~10 nM and higher concentrations, His-CI forms significant amount of dimers in solution. There are two repressor binding sites in ${\phi}11$ cI-cro intergenic region and binding to two sites occurs possibly by a cooperative manner. Two sites dissected by HincII digestion were designated operators $O_L$ and $O_R$, respectively. Equilibrium binding studies indicate that His-CI binds to $O_R$ with a little more strongly than $O_L$ and binding species is probably dimeric in nature. Interestingly His-CI binding affinity reduces drastically at elevated temperatures ($32-42^{\circ}C$). Both $O_L$ and $O_R$ harbor a nearly identical inverted repeat and studies show that ${\phi}11$ repressor binds to each repeat efficiently. Additional analyses indicate that ${\phi}11$ repressor, like $\lambda$ repressor, harbors an N-terminal domain and a C-terminal domain which are separated by a hinge region. Secondary structure of ${\phi}11$ CI even nearly resembles to that of $\lambda$ phage repressor though they differ at sequence level. The putative N-terminal HTH (helix-turn-helix) motif of ${\phi}11$ repressor belongs to the HTH -XRE-family of proteins and shows significant identity to the HTH motifs of some proteins of evolutionary distant organisms but not to HTH motifs of most S. aureus phage repressors.