• Plant Resources
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• 제5권1호
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• pp.17-28
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• 2002

Palynological characters such as pollen grain polar axis length (PL), pollen equatorial diameter (ED), colpus length, colpus width, and P/E ratio of six species of Quercus subgenus Lepidobalanus Endl. from Korea were studied. A significant interspecific variation, unequal distances between the species, and various degree of intraspecific variations were found. The taxonomic value of the pollen morphology parameters measured was found to vary according to species. These results suggest a possible relationship between parameters measured and ploidy level of the Quercus species studied.

• Animal Systematics, Evolution and Diversity
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• 제35권4호
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• pp.182-185
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• 2019

In this study, cytochrome c oxidase subunit I(COI) sequences of 17 individuals from six Korean diogenid species(i.e., 2 Areopaguristes japonicus, 4 A. nigroapiculus, 3 Paguristes digitalis, 4 P. ortmanni, 3 Diogenes edwardsii, and 1 Ciliopagurus kempfi) were determined and analyzed. The DNA barcoding results of this study were consistent with the morphological identification of these six species. Interspecific variations of COI sequences within six Korean diogenid species exceeded the minimum interspecific variation of diogenid hermit crabs in previous studies. Little intraspecific variation exists except for P. digitalis. This study should facilitate further molecular taxonomy of East Asian diogenids.

• Journal of Forest and Environmental Science
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• 제37권1호
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• pp.35-43
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• 2021

The interspecific hybrid of Salix caprea and Salix gracilistyla has never been identified or studied in Korea. Accordingly, this study investigated the flower morphological characteristics of the interspecific hybrid between S. caprea and S. gracilistyla and compared the interspecific hybrid with S. caprea and S. gracilistyla, respectively. The female flowers were investigated for 12 characteristics and the male flowers were investigated for nine. For the female flowers, those of the hybrids were larger than those of S. caprea and S. gracilistyla in terms of catkin length (CL), bract length (BL), and bract width (BW). The hybrids are intermediates between S. caprea and S. gracilistyla in terms of ovary length, width, and stipitate length as well as gland length (GL). For the male flowers, those of the hybrids were bigger than those of S. caprea and S. gracilistyla in terms of CL, BL, and BW. The hybrids are intermediates between S. caprea and S. gracilistyla in terms of catkin width and stamen length (SL). A principal component analysis (PCA) of the female data showed that the first principal component (PC) explained 57.5% of the total variation. The first PC highly correlated the ovary stipitate and pistil style lengths. The analysis was divided into three groups of S. caprea, S. gracilistyla, and the hybrid by the first PC. The results of a PCA of the male data showed that the first PC explained 35.7% of the total variation. The first PC highly correlated with the adelphous SL and was divided into three groups of S. caprea, S. gracilistyla, and the hybrid. The results of the discriminant analysis showed that S. caprea, S. gracilistyla, and the hybrid were distinguishable by flower morphological characteristics. Therefore, the hybrid was distinctly separated from S. caprea and S. gracilistyla by flower characteristics.

• Plant Resources
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• 제5권1호
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• pp.1-6
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• 2002

Genetic improvement of the cultivated soybean [Glycine max (L.) Merr] may be possible through hybridization with its wild progenitor, G. soja Sieb. & Zucc. Interspecific cross between G. max (Hwangkeumkong) and G. soja (IT.182932) was made in the summer of 1997. In F$_2$ the percentage of plant height, nodes per plant, and pods per plant were high but gradually reduced from F$_2$ to F$_4$. In contrast pod length, seeds per pod, and 100-seeds weight were increased gradually through generations advanced. Wild variation as evident in F$_2$ in plant height, number of branches, pods per plant, and 100-seeds weight. Twenty six percent of the F$_2$, 44 % of the F$_3$ and 60% of the F$_4$ segregants showed more G. max traits. The combination of useful traits from both species is possible through interspecific hybridization. The characters that could be transferred from wild species to cultivated species are more pod number, better capacity, and resistance to disease and insects. The interspecific derivatives offer scope for selection for high grain yield. Therefore, introducing genes from G. soja to G. max could be contribute to greater genetic diversity of future cultivars. And semicultivated soybean had some desired characteristics including tolerance to adverse environments and multi-seed characters. It means the infusing of semicultivated germplasm to the cultivated soybean could increase number of seeds and pods per plant significantly, and consequently could enhance selecting potential on yield.

• Animal Systematics, Evolution and Diversity
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• 제37권3호
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• pp.235-241
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• 2021

To provide better taxonomic information of the genus Nectoneanthes, the two DNA barcode regions of mitochondrial cytochrome c oxidase subunit I (COI) and 16S ribosomal DNA (rDNA) sequences of Nectoneanthes oxypoda and N. uchiwa were determined. In addition, the respective sequences of four nereidid species closely related to Nectoneanthes were retrieved from GenBank for comparison and to estimate intra- and inter-specific genetic distances. The aligned sequence lengths of COI and 16S rDNA were 570 bp and 419 bp long, respectively. The mean intraspecific variation in both markers was less than 1% in all species except for that in COI of H. diadroma (1.87%). The mean interspecific variation between N. oxypoda and N. uchiwa was 12.02% regarding COI and 1.85% regarding 16S rDNA. In contrast, the mean interspecific variation between species of other genera was comparably higher(i.e., genus Perinereis: 20.5% in COI and 8.3% in 16S rDNA; genus Hediste: 13.18% in COI and 2.64% in 16S rDNA), compared with that between the two Nectoneanthes species. This result indicated that these Nectoneanthes species are genetically more closely related than other congeneric species of different genera. The DNA barcoding information on Nectoneanthes species generated in this study provides valuable insights for further biodiversity studies on nereidid species.

• The Korean Journal of Ecology
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• 제19권1호
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• pp.71-80
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• 1996

The effects of simulated acid rain on the growth and interspecific competition of Echinochloa crus-galli and Digitaria sanguinalis were studied. Changes of growth in height and dry weight were examined and competition between the two species was investigated using the experimental model proposed by de Wit (1960). The experiments were carried out in the greenhouse, and test plants were germinated and grown for 4 weeks and then sprayed with simulated acid rain of pH 5.6, 4.2 and 2.8 for another 8 weeks. In de Wit replacement experiments, the variation of density and the treatment of simulated acid rain showed little effect on the interspecific competition between E. Crus-galli and D.sanguinalis. The ratio diagram, another method to reveal the interrelations between two competing species, always showed the predominance of E. crus-galli in competition, regardless of density and pH. The interspecific competition of the two species, represented by relative yield total (RYT), revealed that intraspecific competition was stronger than interspecific competition in both species.The treatment of simulated acid rain showed little effect on the growth of E. Crus-galli and D. sanguinalis. Height growth of both species did not differ from that of control (pH 5.6), but root/shoot ratio increased with the decrease in pH of simulated acid rain. Growth of tatal dry weight of E. crus-galli and D. sanguinalis was not influenced by the change of pH, except that D.sanguinalis showed a decrease in the total dry weight at pH 2.8 along with a visible sign of white spots on leaves. Physical environmental conditions can exert an effect on the interrelationships between the two species, but this experiment did not show the reversion of competition, and showed that E.crus-gilli was competitively dominant under any environmental conditions given in this study.

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.269-278
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• 2012

Gobiids are hyperdiverse compared with other teleost groups, with about 2,000 species occurring in marine, freshwater, and blackish habitats, and they show a remarkable variety of morphologies and ecology. Testing the effectiveness of DNA barcodes on species that have emerged as a result of radiation remains a major challenge in evolutionary biology. Here, we used the cytochrome c oxidase subunit 1 (COI) sequences from 144 species of gobies and related species to evaluate the performance of distance-based DNA barcoding and to conduct a phylogenetic analysis. The average intra-genus genetic distance was considerably higher than that obtained in previous studies. Additionally, the interspecific divergence at higher taxonomic levels was not significantly different from that at the intragenus level, suggesting that congeneric gobies possess substantial interspecific sequence divergence in their COI gene. However, levels of intragenus divergence varied greatly among genera, and we do not provide sufficient evidence for using COI for cryptic species delimitation. Significantly more nucleotide changes were observed at the third codon position than that at the first and the second codons, revealing that extensive variation in COI reflects synonymous changes and little protein level variation. Despite clear signatures in several genera, the COI sequences did resolve genealogical relationships in the phylogenetic analysis well. Our results support the validity of COI barcoding for gobiid species identification, but the utilization of more gene regions will assist to offer a more robust gobiid species phylogeny.

• Weed & Turfgrass Science
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• 제2권3호
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• pp.267-273
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• 2013

본 연구는 국내에서 자생하고 있는 241개체의 한국잔디를 지역별로 수집하여 종자 형태적 형질을 조사했으며, 한국잔디의 종자 형태적 특성 및 변이를 알아보고자 연구를 수행하였다. 수집된 한국잔디 241개체 중에서 중지가 99개체로 41% 이상이 수집되었으며, 다양한 형태의 종자 변이를 보였다. 크게 갯잔디형과 들잔디형으로 두 개 그룹으로 나뉘었으며, I과 II군은 화서당 종자수가 30.1개와 17.5개, 종자길이는 4.6과 5.2 mm으로 갯잔디형이 포함되었고, III과 IV군은 화서당 종자수가 59.2개와 45.8개, 종자길이는 3.3과 3.4 mm으로 들잔디형 특성을 나타내었다. 정확한 종간교잡의 정도를 파악하기 위해서는 추가적인 생육특성 및 분자생물학적 연구가 필요하다고 판단되었다.

• Journal of Plant Biology
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• 제39권3호
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• pp.185-188
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• 1996

Randomly amplified polymorphic DNAs were employed to study the genetic variation and gene introgression in potato dihaploids (2n=24) which were generated after interspecific pollination of tetraploid cultivars (2n=4X=48, Solanum tuberosum cv Irish Cobbler, Superior and Dejima) by haploid inducer clones (2n=2X=24, Solanum phureja 1.22, Hes-5 and Hes-6). Genetic variation and DNA marker segregation among dihaploids were observed. Most dihaploids contain S. tuberosum specific RAPD markers but haploid inducer-specific RAPD markers were also found in some dihaploids. Of six different arbitrary 10-mer oligonucletide primers which showed polymorphism betwen tetraploid cultivars and haploid inducers used, three generated amplification products which seemed to be derived from the S. phureja parent. Our results indicate that chromosomes of dihaploids may not be pure S. tuberosum and the dihaploids may not be produced by parthenogenesis.

• The Korean Journal of Ecology
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• 제21권3호
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• pp.301-307
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• 1998

Intraspecific and interspecific isozyme variations and their relationship of 16 local populations in 3 species of Phyllostachys, that is, P. bambusoides, P. nigra var. henonis and P. pubescens were investigated by multi-variate analysis. Leaf isozymes of Phyllostachys such as 6-PGD (6-phosphogluconate dehydrogenase), MDH (malate dehydrogenase), PGI (phosphoglucoisomerase), PRX (peroxidase), PGM (phosphoglutamase), IDH (isocitrate dehydrogenase) showed electrophoretic variations in the number of zymotypes (7, 6, 6, 9, 3 and 5, respectively). In the cluster analysis on the isozymic characteristics, 16 populations were classified into 3 species at the euclid genetic distance of 2.041. P. nigra var. henonis and P. bambusoides were clustered first at 2.813 and then P. pubescens at 3.001. So far, 3 local types of intraspecific ariation were found in P. nigra var. henonis and P. bambusoides.