벼의 잎은 광합성을 위한 주요 기관으로, 동화산물의 생산을 통해 벼의 수량 결정에 영향을 준다. 따라서, 상위엽의 형태적 특징은 다수성 벼 품종의 육성을 위한 필수적인 고려요소이다. 본 연구에서는, 연차간 안정적으로 발현하는 3개의 엽폭 조절 QTL인 qLW4.1, qLW4.2, qLW7을 탐지하였다. 이들은 분석집단에서 나타난 엽폭 표현형 변이의 5.2~44.9% 를 설명할 수 있었다. qLW4.2 영역에 대한 후보유전자 분석 결과, 해당 QTL 영역에서 엽폭 조절 유전자인 NAL1을 발견하였다. 상위엽은 수량에 대해 정의 간접효과 나타냈으며, 그 효과의 크기는 수당립수에 대한 상위엽의 정의 직접효과와 수수에 대한 상위엽의 부의 직접효과에 의해 결정되었다. 한국 벼 유전자원에서 엽폭은 상대적으로 좁은 범위에서 표현형 변이를 나타내었으며, 이는 특정 상위엽폭이 한국 자원에서 선호 되었음을 시사한다. NAL1의 하플로타입 분석결과는 대다수의 한국 자원들이 자포니카형 하플로타입을 지닌 반면에, 모든 통일형 품종들은 인디카형을 지니고 있음을 밝혀냈다. 이러한 결과는 유용 대립유전자형인 자포니카형 NAL1의 도입을 통해 통일형 품종의 다수성 형질을 더욱 향상시킬 수 있음을 의미 한다.
In the 21st century, the risk of the exotic pest being invaded is increasing due to the rise of trading activities. Oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), has been considered to very destructive invader as it is highly intrusive and has a wide host range. In this study, 2,299 samples were collected from 88 locations in 12 countries by quarantine and investigation. Among them, 608 individuals (including B. correcta) were used for COI DNA barcoding analysis based on Neighbor Joining method with P-distance model. Population genetics analysis was conducted for 510 individuals selected from 47 locations of 12 Southeast Asian countries using 15 microsatellite loci. The barcoding analysis resulted in that any clade was not clustered according to a geographical isolation but indicated geographically mixed populations. Population genetics analysis showed shared genetic structure between neighboring countries across borders. Genetic structure of most Korean quarantine groups was more similar to that of Taiwan, China and Thailand in the order of appearance than other countries.
Pleurotus eryngii, an edible white-rot fungus, is cultivated widespread in Eurasia, northern Africa and China. It occupies the second position in the world mushroom market. Despites the importance, the small numbers of studies have been done. To promote the availability of P. eryngii, it is important to know the genome and organization of the fungus. In this study, the whole genome sequence of P5 monokaryon from P. eryngii KNR2312 strain was sequenced using Next Generation Sequencing (NGS) strategy. Identified 222 SSR markers based on newly known genome information and various type of markers used to construct the map consisted of 12 linkage groups (LGs) spanning 1047.8 cM. Using composite interval mapping, 71 quantitative trait loci (QTL)s were identified on 12 linkage groups (LG) for nine traits such as yield, quality, cap color and earliness in four different populations. Clusters of more than five QTLs for various traits were identified on three genomic regions on LG 1, 7, and 9. The largest cluster was identified on LG 1 in the range from 65.4 to 110.4 cM. We performed the genes prediction analysis responsible for yield in the LG1 genomic region with highest logarithm of the odd (LOD) scores The identified genes were involved in biomass degradation and synthesis and signal transduction. However, the region was wide to identifie the genes crucial role in important trait, we need to narrow down. To improve the resolution of QTL mapping, we enlarge the populations crossing with additional 205 monokaryons. Find mapping of QTLs will increases the accuracy and efficiency of interpret the genomic region and enhance the usefulness of genomic information. [Supported by a grant from the IPET (213007-05-1-SBI30), MIFAFF, Republic of Korea.]
Alterations affecting the status of robustness and health can bring about physiological changes including hematological parameters in pigs. To identify quantitative trait loci (QTL) associated with 8 hematological phenotypes (one leukocyte trait, six erythrocyte traits, and one platelet trait), we performed a genome-wide association study using the Porcine SNP 60K BeadChip in an intercross population between Landrace and Korean native pigs. A total of 36,740 SNPs from 816 F2 offspring were analysed for each blood related traits after filtering by quality control. Data were analysed genome-wide rapid association using the mixed model and regression (GRAMMAR) approach. A total of 257 significant SNPs (P<1.36x10-6) on SSC3, 6, 8, 13, and 17 were detected for blood related traits in this study. Interestingly, the genomic region between 17.9 and 130 Mb on SSC8 was found to be significantly associated with RBC, MCV, and MCH. Our results include 5 significant SNPs within five candidate genes (KIT, IL15, TXK, ARAP2, and ERG) for hematopoiesis. Further validation of these identified SNPs could give valuable information for understanding the variation of hematological traits in swine.
Investigating loci compositions by conventional methods is limited in fully addressing complex gene information. We applied self-organizing map (SOM) to characterize Amplified Fragment Length Polymorphism (AFLP) of aquatic insects in six streams in Japan in responding to environmental variables. Locus band presence patterns were clustered by the trained SOM. Presence and absence data of loci were altered and cluster change through recognition was Subsequently expressed to indicate sensitivity to environmental variables. The outlier loci were determined based on the 90th percentile. Subsequently environmental responsiveness was obtained for each outlier in different species. Outlier loci were overall sensitive to pollutants and feeding material. Poly-loci like responsiveness was detected in adapting to environmental constraints. SOM training combined with recognition could be an efficient means of characterizing loci information without knowledge on population genetics a prior.
The mitochondrial COI gene has often been utilized as a molecular marker for species identification. However, it has sometimes caused misidentification for some pairs of closely related species. For detecting complementary barcoding loci, we first screened candidate genes by calculating genetic distances within and between species based on 542 sequences collected from the Genbank by using aphids of the Eriosomatini as an example. Of eight genes analyzed, we selected the ATP6 and ATP8 genes, which exhibited lower intraspecific and higher interspecific genetic divergences than did the COI gene. Secondly, we tested the usefulness of these genes by calculating genetic distances between all the combinations of 44 individuals of 23 eriosomatine species for each of the ATP6, ATP8, and COI genes. In the ATP8 gene, the average intraspecific divergence was lowest (0.6%) and the average interspecific divergence was highest (14.7%). The ATP8 gene evolved more rapidly than did the COI gene if genetic divergence between individuals was sufficiently large, whereas it evolved more slowly than did COI if genetic divergence was less than a threshold (1% in COI distance). As a result, species with intraspecific variation in COI and ATP6 exhibited no genetic variation in ATP8. The pattern of genetic divergence in ATP8 well accorded with the pattern of species delimitation in the present taxonomic system. Thus, we conclude that the use of the ATP8 gene in DNA barcoding could improve the accuracy of species identification in the Eriosomatini and possibly other insect groups.
The previous studies for phylogenetic relationships within Elateridae were carried out, but not constructed a reliable evolutionary hypothesis. This study attempted to establish a robust evolutionary hypothesis, focusing on major subfamilies of the family Elateridae sensu stricto, using extensively selected 12 genetic markers, COI, 16S rRNA, 18S rRNA, 28S rRNA and 8 nuclear genes. As the results, phylogenetic analyses for 12 multiple genes constructed robust phylogeny with almost very strongly supported nodal values (>90%) and represented that the previously questioned systematic positions of nine subfamilies are fully resolved, excepting the basal lineage split. Especially, three subfamilies, which were recently reduced into tribal rank, Hypnoidinae, Oxynopterinae, and Denticollinae are monophyletic, respectively, and it is supported the traditional taxonomic schemes that had been treated these three taxa in subfamily rank. Whereas, Elaterinae, Hiopinae, and Melanotinae are clustered to a monophyletic group. Two tribes, Denticollini and Ctenicerini in Denticollinae are paraphyletic, respectively and it needs to reclassify their systematic positions. This study recovering of relationships between subfamilies using 12 gene loci resulted that their phylogenetic relationships are sufficiently and successfully resolved with strong supported nodes and provided more possible interpretations from subfamily to tribal levels than the previous studies.
품종 육종의 주요 목표중 수량의 증가를 위한 요인들을 선발하는 것이 중요하며, 콩에서 수량을 결정하는 요인들중에서는 협수와 립수가 중요한 요인으로 알려져 있다. 따라서 본 연구는 큰올콩과 익산10호를 교배하여 얻은 F10세대의 RIL 계통을 이용하여 수량에 관여하는 요인중 주당협수와 주당립수 및 협당립수를 조절하는 QTL을 분석하였다. 주당협수는 염색체 5번( LG A1), 6번(LG C2), 8번(LG A2)과 9번(LG K) 및 18번(LG G)에서 5개의 독립된 QTL이 탐지되었으며, 주당립수는 염색체 1번(LGD1a+Q), 6번(LG C2), 9번(LG K), 13번 (LG F)과 17번(LG D2) 및 18번(LG G)에서 6개의 독립된 QTL이 탐지되었다. 협당립수는 2개의 독립된 QTL이 염색체 11번(LG B1)과 19번(LG L)에서 탐지되었는 데 염색체 19번(LG L)에서 탐지된 QTL은 전체 변이의 19.3%를 설명하는 주요 QTL이었다. 한편 주당협수와 주당립수는 염색체 6번(LG C2)과 9번(LG K) 및 18번(LG G)에서 공통된 QTL이 탐지되었다.
The blueberry gall midge, Dasineura oxycoccana (Johnson), which has been recently introduced into Korea, is a notorious pest on blueberries. This invasive insect has rapidly spread throughout Korea including Jeju island. So far, we have no epidemic information, such as invasion routes and subsequent dispersal rates in Korea. To understand population genetics of D. oxycoccana, we have developed 12 novel microsatellite loci. To obtain its sequence data, the next generation sequencing was performed using mixed individuals collected from Korea and USA. The developed loci were polymorphic, with 6 to 16 alleles in 35 individuals from a single population of Hwaseong. The analyses revealed that all 35 individuals had different multilocus genotypes with heterozygosity ranging from 0.568 to 0.790. These markers will facilitate population genetic studies of D. oxycoccana.
Lycorma delicatula (White 1845), which has been recently introduced into Korea, is a notorious pest on grapes. This invasive insect has rapidly spread throughout central and southern Korea. To date, we have no behavioral or population genetics information, such as invasion routes and subsequent dispersal rates in Korea, to help understand and control populations of L. delicatula. Here, we have developed 15 novel microsatellite loci for L. delicatula. The isolated loci were polymorphic, with 2 to 19 alleles in 42 individuals from a single population in Cheonan. The analyses revealed that all 42 individuals had different multilocus genotypes with heterozygosity ranging from 0.214 to 0.866. Eleven of the 15 loci did not deviate significantly from Hardy-Weinberg equilibrium. The isolated markers will facilitate population genetic studies of L. delicatula.
Ten novel microsatellite loci were isolated and characterized from the beet armyworm, Spodoptera exiqua. The isolated loci are polymorphic, with 2~12 alleles in 18 individuals from several populations in Korea. All 18 individuals had different multilocus genotypes with heterozygosity ranging from 0.089 to 0.843. Nine of 10 loci kept the Hardy-Weinberg equilibrium in adjusted significance thresholds. We report the development of microsatellite markers for S. exiqua potentially suitable for further studies of population structure, dispersal, and host relationship.
The Laodelphax striatellus(SBPH) (Homoptera:Delphacidae) is a major rice insect pest in Asia. It brings the indirect damage by transmitting Rice Stripe Virus (RSV) and Rice Black-Streaked Dwarf Virus (RBSDV). Molecular markers for genetics studies will be very helpful for dynamics of SBPH and viruses. For surveying genetic variation among populations of SBPH by microsatellite analyses, we used an enrichment strategy to develop microsatellite markers from SBPH. Eight polymorphic microsatellite loci were selected to characterize genetic structuring of SBPH populations.
The Laodelphax striatellus(SBPH: Small Brown Plant Hopper) is known to be not overwintering in South Korea and migrate from China to Korea every year by now, but these days many evidence support the possibility of SBPH overwintering. These insects do considerable damage to the rice production in Korea. If they will come from China, identification of origin of migration is very important to make countermeasure against SBHP outbreak. So we want to know exact the route of long-distance migration of them. In this study, we have developed some microsatellite markers for basic population genetic analysis of SBPH. We will show the genetic characteristics of them
Ten novel microsatellite loci were isolated and characterized from the soybean aphid, Aphis glycines. The soybean aphid was recently introduced into North America where it has become a serious pest of soybeans. This invasive pest has rapidly spread throughout the midwestern United States and southern Canada since 2000. The isolated loci were polymorphic, with two to 18 alleles in 20 individuals from a single population in Korea. The analyses revealed that 19 individuals had different multilocus genotypes, showing expected heterozygosity values ranging from 0.180 to 0.891. We report the development of microsatellite markers for A. glycines potentially suitable for further studies of population structure, dispersal, and host alternation.
The Nilaparvata lugesn(BPH) and Laodelphax striatellus(SBPH) are major insect pests of rice in Korea. These BPHs migrate from China to Korea, but we have not exactly known about the route of long-distance migration of them. Molecular markers including microsatellite will be critical to asses gene flow in relation to geographical distance. In our work several microsatellite markers were developed for basic population genetic analysis of BPH and SBPH. Among each 21 microsatellite markers in BPH and SBPH, we could select 6 markers for BPH and 2 markers for SBPH as putative markers for analysis of population genetics. Others are further investigated for the possibility as markers. Development of polymorphic microsatellite loci are final stage of our work. But for good microsatellite markers to population genetics, we should do more experiments. Our work for development of microsatellites should facilitate the study of future population genetics of BPH and SBPH, and eventually elucidate the route of BPH and SBPH migration to Korea.