국내의 주요 산느타리 품종인 호산47(일핵, 산타리 배우자), GB19(일핵, 산타리 배우자), 호산, 여름느타리1호, 삼복, 강산, 약산, 자산, 향산, 여름느타리2호의 유전체를 Hiseq을 이용하여 해독하였고 이 서열 정보에서 SSR을 분리하여 특성구명을 하였다. 일핵균사인 호산 47, GB19 의 유전체의 크기는 각각 37.3와 37.2 Mbp이고, 이핵균사인 나머지 산느타리 품종의 유전체 크기는 47.1~61.1 Mbp인 것으로 밝혀졌다. 품종별 총 SSR의 수는 HS47이 711개로 가장 적고, 강산이(GS)이 1.5배 많은 1,106개로 최다를 기록하였다. SSR의 repeat motif 중에서 hexanucleotide 와 octanucleotide가 가장 많은 빈도로 관찰되었고, 가장 많이 관찰되는 반복서열은 CGA/TCG, A/T, CTC/GAG이었다. SSR의 길이는 모든 품종에서 변이가 많아 유용성이 높은 20~30 nt가 가장 높은 비중인 70%를 차지하였다.
우리나라 참나리 2배체와 3배체 중 임의 선발된 56 개 지역의 참나리에 대하여 EST-SSR이용하여 각 genome 간의 유전적 변이와 유연관계를 분석하고자 수행되었다. 최근 백합속에서 개발된 19개의 EST-SSR 중에서 7개의 primer가 참나리 2, 3배체 종내 유전적 변이 분석에 적합한 것으로 나타났다. 서해안, 남해안 제주도의 원거리 지역에 분포하는 2배체 참나리들은 지역에 관계없이 다양한 유전적 변이를 나타내었으나, 소청도, 울릉도 및 내륙에 분포하는 3배체 참나리는 비교적 단순한 변이를 나타내었다. 다형성을 나타낸 총 121개의 SSR 밴드를 사용하여 UPGMA 방법으로 계 통도를 작성한 결과 2배체 집단에서는 유전적 변이가 다양한 반면 3배체 집단에서는 비교적 변이가 적은 것 으로 나타났다. 2배체 집단에서 아차도 계통들이 남해 안의 다른 2배체와 뚜렷이 구분되는 cluster를 형성하 였고, 3배체 집단에서는 소청도 참나리가 다른 지역과 는 구별되는 독특한 밴드패턴을 나타내었다. 본 연구에 서 선발된 EST-SSR마커들은 금후 참나리 2, 3배체 집단의 유연관계를 분석하는데 유용하게 사용될 수 있 을 것으로 생각된다.
Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. In this study, a total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST-SSR markers were developed based on the trials of transferability of these primers in little millet. The EST-SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. The average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. The polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST-SSR markers in assessing genomic relationships in little millet. The findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.
High temperature is one of major environmental stress. Heat tolerance managing is difficult through the phenotypic selection, so marker assistant selection (MAS) using molecular markers like as RAPD, SSR etc. was tried to select useful traits for heat tolerance. Fourteen SSR markers reported by previous research were selected for this research. We tried to evaluate 14 SSR markers for MAS using 31 useful wheat resources including 24 crossing line from Turkey, six Korean wheat cultivars and Chinese spring. The average of the number of alleles and PIC values in this study were 6.14 and 0.64, respectively. Two major clades and four sub clades were grouped by phylogenetic tree using UPGMA. Four Korean wheat cultivars were distinct from other Turkey resources in the phylogenetic dendrogram. From the results, we expected that these markers were able to adapt to screening wheat genotyping for heat tolerance.
EST-SSRs were developed in Brassica napus by database mining. We isolated 7,802 EST-SSRs from the B. napus 643,946 ESTs deposited in the NCBI. With the cut-off value of >10 repeats in di-nucleotide repeats and >7 tri-nucleotide repeats, 303 ESTs were suitable for primer designing for PCR amplification. Of the sixteen possible di-nucleotide combinations, only three types of repeats (AC/GT, AG/CT, and AT/TA) were present among the di-nucleotide EST-SSRs. Whereas, 27 tri-nucleotide repeat motifs from the 64 possible combinations were present. The repeat numbers ranged from 10-15 in di-nucleotide repeats and 7-9 in tri-nucleotide repeat motifs, respectively. By checking PCR amplification in 10 Korean rapeseed breeding lines or cultivars, 234 primer pairs showed successful PCR amplification and 142 of the 234 primer pairs revealed polymorphism among the control cultivars or breeding lines. While the repeat length does not related with the SSR polymorphisms, the repeat motif number showed positive relation with the polymorphism generation by showing higher repeat numbers with higher polymorphisms. We are here presenting the PCR amplifiable primer sequences of the 234 SSR primer pairs to aid in the germplasm management and breeding programs of the B. napus in Korea.
It is very crucial to evaluate the genetic diversity of peanut genetic resources for identification of peanut germplasm accessions and variety improvement. Cultivated peanut generally has two subspecies, hypogaea and fastigiata. In this study, we identified peanut into three plant types, virginia (var. hypogaea), spanish (var. vulgaris), and valencia (var. fastigiata). Former one belongs to ssp. hypogaea and latter two are involved in ssp. fastigiata. Twenty SSR markers were used to assess the genetic variation of three sets, hypogaea, vulgaris, and fastigiata, respectively. Out of variety-specific SSR primers tried in this study, ten pairs of SSR primers showed polymorphisms. Each accession could be identified by a specific set of polymorphic SSR primers, and allele number was evaluated among accessions, with an average of 6.7 in var. hypogaea and 5.4 in var. vulgaris and fastigiata. For evaluation of genetic diversity, gene diversity ranged from 0.336 to 0.844 and PIC (polymorphism information contents) ranged from 0.324 to 0.827 were investigated. Dendrograms based on genetic distances were constructed, which showed the existence of three different clusters. And these three different clusters might be associated with the genes involved in three plant types. The results also suggested that there were plentiful SSR polymorphisms among peanut germplasm accessions in RDA (Rural Development Administration, Korea) Genebank and SSRs might play an important role in evaluating peanut accessions and cultivar improvement.
The SSR markers were generally used to analysis the plant genetic diversity, but it have been rarely reported in case of castor bean. We constructed the microsatellite-enriched genomic library and sequenced totally 775 clones to obtain the microsatellite sequence information of the castor bean. Among the sequenced clones, one hundred fifty clones (19.3%) were redundant and four hundred twenty (67.2%) were found to contain microsatellite sequences within the remaining 625 unique clones. A total of 237 primer pairs were designed based on the sequenced microsatellite clones information and evaluated for polymorphism in ten castor bean accessions. Twenty-eight SSR markers produced reproducible polymorphic bands and were further characterized using a diverse set of 25 castor bean accessions. The majority of unique SSRs revealed dinucleotide motives (84%) on the other hand the ratio of trinucleotide motives was 15%. A microsatellite enriched library from the Ricinus communis L. was mainly consisted of [(AG), (GA)/(CT), (TC)] and [(CTT)/(AAG)] microsatellite motifs. The length of dinucleotide SSRs ranged from 4 to 50 repeats with an average 12.4, and that of trinucleotide SSRs from 4 to 56 with an average of 7.35 repeats. These newly developed microsatellite markers will be useful for breeding system and classification of Ricinus communis L.