• 한국자원식물학회지
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• 제25권6호
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• pp.745-752
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• 2012

Compared to wide ranges of genetic variation of natural populations, very limited Miscanthus cultivar has been released. This study was the first report on the development of Miscanthus cultivar by means of radiation breeding. Seeds of M. sinensis were initially exposed to gamma rays of 250 Gy for 24 h, generated from a $^{60}Co$ gamma-irradiator. The irradiated seeds were sown and then the highly tiller-producing mutants were selected for this study. Biomass-related parameters including tiller number, plant height, stem diameter, and leaf number were measured. Ploidy level and internal transcribed spacer (ITS) were investigated to characterize the mutants compared to wild type (WT) Miscanthus. Plant height and tiller number were negatively related, where multi-tillering mutants were relatively short after 4 month growth. However stem diameter and leaf number were greater in mutants. All the materials used in this study were diploid, implying that the mutants with greater tiller numbers and stem diameter were not likely related to polyploidization. Based on the sequence of ITS regions, the mutants demonstrated base changes from the gamma irradiation where G+C content (%) was decreased in the ITS1, but increased in ITS2 when compared to WT sequence. ITS2 region was more variable than in ITS1 in the mutants, which collectively allows identification of the mutants from WT. Those mutants having enhanced tillers and allelic variations might be used as breeding materials for enhanced biomass-producing Miscanthus cultivars.

• 한국육종학회지
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• 제40권3호
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• pp.223-227
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• 2008

In rice, tillering is an important trait determining yield. To study tillering at the agricultural and molecular aspects, we have examined a spontaneous rice mutant that showed reduction in the number of culms. The mutant was derived from a $F^6$ line of the cross of Junambyeo*4 / IR72. It could produce, on average, 4 tillers per hill in the paddy field while wild-type plants usually have 15. Except the reduced culm numbers, they also show pale green phenotypes. The phenotypes of this mutant were co-segregated as the monogenic Mendelian ratio (${\chi}^b=0.002$, p=0.969). In order to locate a gene responsible for the rcn phenotype, the mutant with the japonica genetic background was crossed with Milyang21 of the indica background. Bulked segregant analysis was used for rapid determination of chromosomal location. Three SSR markers (RM551, RM8213, and RM16467) on chromosome 4 were genetically associated with the mutant phenotype. Each of the 217 $F_2$ plants was genotyped with simple sequence length polymorphisms. The data showed that RM16572 on chromosome 4 was the closest marker that showed perfect co-segregation among the $F_2$ population. We suggest the new rcn gene studied here name as $rcn10^t$ because there was no report which exhibit a rcn phenotype with a pleiotropic effect of pale green (chlorophyll deficiency), and mapped at same position on chromosome 4.

• 한국약용작물학회지
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• 제12권3호
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• pp.219-225
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• 2004

재식밀도를 달리하여 파종한 후 최고분얼기에 엽의 전개정도를 기준으로 하여 분얼순서를 정한 후 분얼순서에 따른 생육특성, 수량구성요소 및 수량형질간 종실수량에 기여하는 정도를 분석한 결과를 요약하면 다음과 같다. 1. 생육형질의 경우 재식밀도간에는 표준구인 $60{\times}15\;cm$에 비하여 소식구인 $60{\times}25\;cm$에서 간장은 20 cm 짧았고 간직경은 0.9 mm 굵었고 총포수는 4.7개 많았으나 착립 절위는 1.7절 낮게 착립되었다. 분얼출현이 늦을수록 간장은 짧아지고 간직경은 가늘어졌다. 2. 수량형질의 경우, 채식밀도간에는 표준구인 $60{\times}15\;cm$ 구에 비하여 소식구인 $60{\times}25\;cm$ 구에서 지간장(枝桿長)은 2.55배 길었으며 분얼당 종실수는 2.45배, 분얼당 총포수는 1.96배 많았으나 등숙율은 12.2% 낮았으나 100립중은 0.5 g 가벼웠다. 3. 분얼순서간에는 분얼출현이 늦을수록 지간장(枝桿長)은 짧아지고, 분얼당 종실수는 적어지는 경향이었다. 총포수는 주간에서 가장 많았으나, 분얼출현이 늦을수록 더 뚜렷하게 감소하는 경향이었다. 100립중은 $60{\times}15\;cm$ 구에서는 출현이 늦은 분얼일수록 가벼워졌으나, $60{\times}25\;cm$ 구에서는 뚜렷한 차이를 나타내지 않았다. 4. 10a당 수량에 대한 분얼순서별 기여정도는 두 재식 밀도구에서 주간을 포함한 1차분얼인 1, 2, 3, 4째 출현된 분얼에서 표준구인 $60{\times}15\;cm$ 구에서 84.5%, 소식구인 $60{\times}25\;cm$ 구에서 84.1%를 차지하여 1차 분얼이 수량에 대한 기여도가 높았다. 5. 계식밀도별 10a당 수량에 대한 경로계수를 분석한 결과를 보면 직접효과는 표준구인 $60{\times}15\;cm$ 구에서는 분얼당 종실수, 100립중, 등숙율 순이었으며, 소식구인 $60{\times}25\;cm$ 구에서는 분얼당 종실수, 분얼당 총포수, 등숙율, 100립중 순이었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.141-141
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• 2017

The ubiquitin-proteasome pathway is the major regulatory mechanism in a number of cellular processes for selective degradation of proteins and involves three steps: (1) ATP dependent activation of ubiquitin by E1 enzyme, (2) transfer of activated ubiquitin to E2 and (3) transfer of ubiquitin to the protein to be degraded by E3 complex. F-box proteins are subunit of SCF complex and involved in specificity for a target substrate to be degraded. F-box proteins regulate many important biological processes such as embryogenesis, floral development, plant growth and development, biotic and abiotic stress, hormonal responses and senescence. However, little is known about the F-box genes in wheat. The draft genome sequence of wheat (IWGSC Reference Sequence v1.0 assembly) used to analysis a genome-wide survey of the F-box gene family in wheat. The Hidden Markov Model (HMM) profiles of F-box (PF00646), F-box-like (PF12937), F-box-like 2 (PF13013), FBA (PF04300), FBA_1 (PF07734), FBA_2 (PF07735), FBA_3 (PF08268) and FBD (PF08387) domains were downloaded from Pfam database were searched against IWGSC Reference Sequence v1.0 assembly. RNA-seq paired-end libraries from different stages of wheat, such as stages of seedling, tillering, booting, day after flowering (DAF) 1, DAF 10, DAF 20, and DAF 30 were conducted and sequenced by Illumina HiSeq2000 for expression analysis of F-box protein genes. Basic analysis including Hisat, HTseq, DEseq, gene ontology analysis and KEGG mapping were conducted for differentially expressed gene analysis and their annotation mappings of DEGs from various stages. About 950 F-box domain proteins identified by Pfam were mapped to wheat reference genome sequence by blastX (e-value < 0.05). Among them, more than 140 putative F-box protein genes were selected by fold changes cut-offs of > 2, significance p-value < 0.01, and FDR<0.01. Expression profiling of selected F-box protein genes were shown by heatmap analysis, and average linkage and squared Euclidean distance of putative 144 F-box protein genes by expression patterns were calculated for clustering analysis. This work may provide valuable and basic information for further investigation of protein degradation mechanism by ubiquitin proteasome system using F-box proteins during wheat development stages.