Sucrose, raffinose, and stachyose are major soluble sugars in soybean seeds. Sucrose is the major source of energy for fermentation and contributes to the sweetness of soybean foods. The soyfood and animal feed markets prefer soybean cultivars with high sucrose because they provide high levels of energy and better tasting food and feed. The objective of this study is to select soybean lines with high sucrose content. A total of 295 soybean genotypes including 13 current cultivars, 34 germplasms, and 248 breeding lines were planted at the field. After harvesting, sucrose contents for 295 genotypes were measured through HPLC method. Wide variation was detected among the 295 genotypes in sucrose content. The sucrose content ranged from 15.1 to 39.0 g. kg-1 in 13 current cultivars. The highest sucrose content was identified in “Dayangkong” (39.0 g. kg-1), whereas was lowest in “Seomoktae” (15.1 g. kg-1). The sucrose content ranged from 9.6 to 47.6 g. kg-1 in 34 germplasms. The sucrose content ranged from 0.9 to 46.4 g. kg-1 in 248 breeding lines.

찰옥수수, 단옥수수, 초당옥수수 등은 종실에 전분이 저장되는 과정에서 돌연변이가 발생하여 전분의 구성에 차이를 일으키며 이들의 유전자들 상호간에는 상위성이 존재한다. 배유의 저장전분에 관여하는 유전자 중에서 brittle1(bt1), brittle2(bt2), shrunken1(sh1), shrunken2(sh2), sugary1(su1), sugary2(su2), sugary enhancer(se)들은 전분 합성을 억제하고 amylose extender(ae), dull(du), floury(fl), opaque2(o2), waxy(wx)들은 배유 내에 전분의 구성 및 구조 등을 변경한다. 전분합성을 억제하는 유전자들은 전분의 구성을 변경하는 유전자에 상위성을 가지며 그들의 작용을 피복한다. 이들의 사실을 기초로 본 시험은 단옥수수(se) 유전자와 찰옥수수(wx) 유전자를 함께 가지는 자식계통을 만들어 육종 소재로 활용하고자 수행하였다. 2011년에 se 유전자를 가진 자식계통과 wx 유전자를 가진 자식계통을 상호 교배하여 F1 종자를 만들고 2012년 이들을 자식(selfing)시켰다. 멘델에 유전법칙에 따라 유전자형은 Se_Wx_:Sesewxwx:seseWx_:sesewxwx가 9:3:3:1로 분리되고 표현형 분리비는 이들 유전자 간의 상위성에 따라 일반옥수수, 단옥수수, 찰옥수수가 9:4:3으로 표현된다. 이들 분리1세대(S1) 종자를 White light transilluminator (LCF-900-470V, Ultra Violet Products)를 이용하여 찰옥수수의 표현형을 나타내는 종자를 골라 2013년 4월 중순에 파종하였다. 앞으로 이들을 자식(selfing)시켜 분리2세대 종자를 수확하고 단옥수수의 형질을 나타내는 것을 분리하면 이들은 찰옥수수(wx)와 단옥수수(se)의 유전자를 동시에 가지는 double mutant일 것으로 사료되며 분자마커 및 검정교배를 통해 유전자들을 확인할 수 있을 것으로 생각된다.

Common buckwheat has the sporophytic self-incompatibility mechanism and that’s why it has the ability to cross pollinate between two plants with different styles (thepin type and thrum type). The S supergene is thought to govern self-incompatibility, flower morphology and pollen size in buckwheat. Already, we have produced self-compatible buckwheat lines by an interspecific hybridization between Fagopyrum esculentum and F. homotropicum by embryo culture. The pollen size of F1 plants produced by a cross between a pin type plant and the self-compatible plant was similar to that of the self-compatible lines and segregated together with flower morphology without exception. The pollen tubes of the self-compatible plants were compatible with styles of the pin plants but incompatible with the styles of thrum plants. But, the pollen tubes of thrum flowers were compatible with the styles of self-compatible plants. Also, the pollen tubes of pin flowers were incompatible with the styles of self-compatible plants. Already, from these results, we have reported a tentative genotype for heterostyle and homostyle flower types. Homomorphism was controlled by a single allele Sh, while the pin/thrum-complex gene was governed by a single genetic locus S, with two alleles, S and s, which control Ss (thrum-type) as well as the ss (pin-type), respectively. Corresponding represents the case of a single locus S with three alleles, Sh, S and s, and the phenotypes, homomorphic, pin and thrum. It can be characterized by relationship of dominance, S>Sh>s. Using the two self-fertile lines, one is considered as the long-homostyle flowers and the other is considered as the short homostyle flowers. If the short-homostyle trait had arisen by recombination in the S supergene, its genotype would be considered to be GIs ip a/GIs ip a. The pollen tubes of the short-homostylous plant should be compatible with the styles of thrum plants. Also, the pollen tubes of short-homostylous plants should be incompatible with the style of long-homostylous plants, and the reciprocal cross also should be incompatible, because the genotype of long homostyle is gis Ip PA/gis Ip PA. Furthermore, the flower morphology of F1plants produced by the cross between cross and short homostyle flowers should be thrum or short homostyle and only short-homostylous plants should be produced by the cross between pin and short homostyle flowers. However, the compatibility or incompatibility of short homostyle flower was not clarified. So, we need to clarify the compatibility or incompatibility of the style of short homostyle flowers for the next step.

In U.S.A. maize breeding, exotic germplasm is considered as high-risk and usually introduced by backcrossing specific traits into elite lines. The U.S.A. maize germplasm base is narrow. Only a few open-pollinated varieties are well represented in current programs. Currently, the barrier in using of exotic germplasm in the U.S.A is less formidable than in the 1980s. The major reason is that U.S.A materials are now used in tropical breeding to accelerate earlier maturity and lodging resistance. These exotic materials, developed with U.S.A germplasm, are being introduced back into the U.S.A.Since1994, the ARS-led Germplasm Enhancement of Maize (GEM) project has sought to help broaden the genetic base of America’s corn crop by promising exotic germplasm and crossing it with domestic lines. New hybrids derived from such crosses have provided corn researchers and the producers. These may include improved or alternative native source of resistance to insect pests such as corn rootworms and diseases like northern leaf blight. GEM’s aim is to provide source of useful genetic maize diversity to help the producers to reduce risks from new or evolving insect and disease threats or changes in the environment or respond to new marketing opportunities and demand. During the 2009 growing season, the Ames (Iowa) and Raleigh (North Carolina) locations managed or coordinated evaluations on 17,200 nursery plots as well as 14,000 yield trial plots in Ames and 12,000 in Raleigh. A new “allelicdiversity” study is devoted to exploring and capturing the genetic variation represented by over 300 exotic corn races. Since 2001, GEM has released 221 new corn lines to cooperators for further development into elite commercial new hybrids. GEM has already identified about 50%-tropical, 50%-temperate families tracing primarily to tropical hybrids that are competitive with commercial checks. In North Carolina State University program, they have examined the potential of tropical inbredand hybrids for U.S.A. breeding by crossing temperate-adapted, 100%-tropical lines to U.S.A hybrids. There should be favorably unique alleles or genomic regions in temperate germplasm that can be helpful in tropical maize improvement as well as utilization of tropical lines in temperate areas.

Brachypodium has been focused as new model plant for grass species. Like small size, small room requirement, and fast growth, Brachypodium shows numerous advantages as a model plant. Brachypodium is a typical grass at the genome level, which also exhibits an overall similarity of gene content and gene families when compared with rice (Oryza sativa) and sorghum (Sorghum bicolor) genomes. Brachypodium is an excellent material for structural and functional genomic studies in grass species. Targeting-Induced Local Lesions IN Genomes (TILLING) is a high-throughput technique and an approach for reverse genetics study. Moreover, it has been wildly utilized to find induced mutation. Bradi3g45515 is orthologue of the cellulose synthase-like HvCslF8 in barley. For TILLING library construction, 384 M2 Brachypodium mutants induced by chronic-gamma irradiation were used. Single nucleotide polymorphysm (SNP) and small deletion in Bradi3g45515 were searched through TILLING analysis. Template DNA for PCR reaction were prepared according to two dimensional pooling (eightfold) strategy. Heteroduplex DNA was digested by SURVEYOR nuclease (TRANSGENOMIC) and the DNA fragment was detected using polyacrylamide gel electrophoresis. Positive signal appeared at polyacrylamide gel from more than 4 lines and their Bradi3g45515 region were sequenced. SNP(s) were identified in 509-2 and 677-3 mutant line. Cellulose content and/or cell wall materials content will be measured using these mutants.

Soybeans [Glycine max (L.) Merr] are an important source of nutrients including protein, oils and various useful secondary metabolites. Phosphatidylcholine (PC) component serves as a nerve cell membrane material and a choline supplier, so it may improve memory function in subjects suffering from memory impairment and dementia. Content of PC component in soybean seed may depend on genotype and environment. Genotype with high PC content is valuable in breeding project. Fifty-seven soybean genotypes were cultivated at first year. After harvesting, PC contents were analyzed. Content (mg/kg) of PC component was from 7.02 to 19.55. At second year, 111 genotypes including 57 genotype used at first year were cultivated. After harvesting, PC contents were analyzed. Content (mg/g) of PC component was from 0.061 to 12.324.

‘Youhan’ (Hordeum vulgare L.), a new whole crop barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA in 2012. ‘Youhan’ has the growth habit of III, light green and middle size leaf, hooded and lax-type spikes. The cultivar showed 107 cm of culm length, 641 spikes per m2. Heading date of ‘Youhan’ was May 1, one day later than that of check cultivar ‘Yuyeon’ in upland, and 2 days earlier than that of check in paddy field. Maturing time was similar to check cultivar ‘Yuyeon’ as June 4 in upland and May 31 in paddy field. ‘Youhan’ also showed better winter hardiness, the resistance to lodging and disease than those of check cultivar. The average forage dry matter yield in the regional yield trial was about 12.6 and 12.0 ton ha-1 in upland and paddy field, respectively, which were 6%, 5% higher than that of the check. It also showed 7.3% of crude protein, 26.8% of ADF(Acid Detergent Fiber), 47.8% of NDF(Neutral Detergent Fiber), and 67.7% of TDN(Total Digestible Nutrients), including higher grade of silage quality for whole crop barley. Fall sowing cropping of ‘Youhan’ is recommended only in areas where average daily minimum mean temperatures in January are higher than －8°C, and it should not be cultivated in mountain areas of Korea.

고품질 벼 품종육성과정에서 고식미계통을 저세대에서 선발하는데는 많은 어려움이 있다. 최근에는 식미연관 분자표지들이 개발되고 있는데, 본 시험에서는 이러한 분자표지를 자포니카간 교잡계통에 적용하여 육종적 활용 가능성을 검토고자, 자포니카 4개 조합에서 육성된 F3계통을 관행선발과 분자표지에 의한 선발(MAS)로 나누어 선발하였다. 분자표지는 G4등 SNP마커 13개를 분석하였고, 이들 분자표지에 의한 식미회귀식값을 구하여 고식미계통을 추정하여 선발하였다. 관행선발에 의한 선발비율은 38%, MAS에 의한 선발비율은 34%였다. MAS와 관행선발을 병행하여 선발하였을때는 16%의 계통이 선발되었다. 분자표지 13개로 교배모본들을 군집분석한결과, 2개 군으로 나누어지며, 1군의 교배모본들이 식미회귀식값과 밥의윤기치가 2군보다 높게 나타났다. 분자표지분석에 의한 식미회귀식값은 교배조합별 모본들 간에는 상관관계가 일정한 경향을 보이지는 않았지만, 전체 모본들에 대해서는 유의한 상관관계가 인정되었다. 본 시험에 사용된 분자표지들은 식미관련 밥의윤기치가 높은 계통을 선발할 수 있는 확률이 높을 것으로 기대된다.

고추 탄저병은 국내에서 아주 피해가 심한 병 중의 하나로 본 연구팀은 십수 년 동안 탄저병 저항성에 대해 유전분석을 수행하는 동시에 저항성 품종 육성에 노력을 기울여 왔다. 이전에 사용하였던 탄저병 저항성 소재는 Capsicum baccatum 종의 PBC81 accession이었는데, 이와 가장 교잡화합성이 높았던 C. annuum 종의 SP21 계통을 모친으로 사용하여 종간 교잡을 수행하였고, 이에 대한 BC1F1과 BC1F2 분리집단에서 QTL mapping을 수행하여 두 가지의 탄저병(Colletotrichum acutatum과 C. capsici)에 대한 각각의 저항성 주동 QTL을 탐색함과 동시에 연관된 분자표지를 개발하였다. 본 연구에서는 탄저병 저항성 소재로 PBC81이 아닌 PI594137과 AR을 사용하여 NGS re-sequencing을 수행한 후 대량의 SNP를 탐색하고자 하였다. PI594137은 C. baccatum 종에 속하며, PBC81보다 좀 더 broad spectrum resistance를 보인다. AR은 AVRDC에서 분양 받은 재료인데, C. chinense Jacq. PBC932의 열성 저항성을 C. annuum에 도입한 계통이다. 탄저병 저항성 QTL mapping은 Golden aji(C. baccatum, 탄저병 이병성)와 PI594137의 F2 분리집단과 SP211(C. annuum, 탄저병 이병성)과 AR의 F2 분리집단에서 수행할 계획이어서 각각의 양친 사이(Golden aji vs. PI594137과 SP211 vs. AR)에서 SNP를 탐색하였다. NGS re-sequencing을 통해 읽혀진 염기서열 총 길이는 PI594137이 40.5Gbp, Golden aji가 12.1Gbp, AR이 12.8Gbp, SP211이 11.5Gbp였다. 이 염기서열을 사용하여 생물정보학적 분석((주)씨더스에 의뢰)을 수행하였는데, PI594137과 Golden aji 사이에서 333,816개, AR과 SP211 사이에서 1,218,595개의 SNP를 최종적으로 탐색할 수 있었다. 탐색된 SNP는 탄저병 저항성 QTL mapping 분석에 유용하게 사용될 수 있을 것이다.

전 세계적으로 채소 종자시장의 규모가 커짐에 따라 종자 시장 보호를 위한 다양한 전략이 요구되고 있다. 최근 육종 편의성을 높이고 우수한 유전자원을 보호하기 위한 분자생물학적인 방법들이 활발하게 개발되고 있다. 이원적 전사 유도시스템(Binary trans-acitvation system)은 목적 유전자의 발현을 유도하는 프로모터가 전사촉진인자를 가지고 있는 배우체와의 교배를 통해서만 활성화 되는 형질전환 시스템이다. F1 식물체에서 선택적으로 유전자의 발현시킬 수 있는 이 시스템은 모본과 부본의 교배를 통해 생산되는 작물에서 F1 선택적으로 불임을 유도는 방법으로 활용되어 유전자원 보호 및 육종 편의성 증대를 위한 재료로 이용될 수 있다. 본 실험에서는 배추 작물에서 이 시스템의 이용 가능성을 신속하게 검정하기 위하여 이원적 전사촉진시스템 카세트가 각각 도입된 T0 형질전환체를 교배하는 방법을 사용하였다. 이를 위하여 토양미생물(Agrobacterium tumefaciens)을 이용하여 전사유도 카세트와 활성화 카세트를 각각 형질전환하여 T0 형질전환체를 생산한 후 유전자 도입이 확인된 T0 형질전환체를 모부본으로 F1을 생산하였다. 또한 모본과 부본의 교배조합 능력을 검정하기 위하여 두 카세트가 모본과 부본, 또는 부본과 모본이 되도록 조합하여 유전자 발현 및 유전적 안정성을 F1세대에서 검정하였다.

Quantitative trait locus (QTL) mapping is a highly effective approach for studying genetically complex forms of plant shattering. With QTLs mapping, the shattering loci can be described. SSR marker is based on the imformation of Simple Sequence Repeat and easy to analyze using PCR and has high reproducibility. For analyzing QTLs associated with shattering, we selected 219 SSR markers from 254 SSR markers and used them for implementing Mapmaker(Ver. 3.0) and Mapchart(Ver. 2.2). Mapmaker help to calculate distances between each markers and Mapchart is a program for drawing Genetic map. This Genetic map of rice (Oryza sativa L.) covering 2082.4 cM with 9.5 cM between makers in the Kosambi function has been constructed using 120 F1 DH plants from a single cross between the indica variety Chungchung and the japonica variety Nagdong.

MicroRNAs (miRNAs) are a class of non-coding RNAs of approximately 21-nt which play important roles in regulating gene expression in plants. Although many miRNA studies have focused on a few model plants, the miRNAs and their target genes remain largely unknown in pepper, one of the most important crops cultivated worldwide. Here we employed high-throughput small RNA sequencing to extensively identify miRNAs in pepper from 10 different libraries, including leaf, stem, root, flower, and six developmental stage fruits. Based on bioinformatics pipeline, we successfully identified 29 and 35 families of conserved and novel miRNAs, respectively. We noticed that some miRNAs, whose targets were validated experimentally in this study, exhibited prominent changes in expression levels during fruit development stages. From the qRT-PCR analysis of the target mRNAs, including the SBP-transcription factor and F-box protein, we found that expression of these two target mRNAs gradually decreased in general during fruit development and was negatively correlated with the expression of their corresponding miRNAs. The validation of miRNA-directed cleavage of these target mRNAs, combined with the results of qRT-PCR analysis, likely suggests that some miRNAs in pepper may play a role in fruit development. Conclusively, our study first utilizes high-throughput sequencing to identify and characterize conserved and novel miRNAs and their targets in pepper, providing a basis for understanding the functional roles of miRNAs in pepper.

The most important factor in breeding program is to obtain the value-added genetic line. Generally, breeders develop genetic sources using several methods such as segregation-breeding, cross-breeding, backcross-breeding, mutation induction, tissue culture and so on. Here, we present one classical way but very valuable method called cell fusion or protoplast fusion to create genetic sources for the breeding practice. The method we developed was the asymmetric somatic-hybridization of protoplast isolated from carrots. This is rather to transfer the nucleus from the high quality F1 hybrid to other mediocre line to produce a new carrot line. Since the breeding a carrot line for higher quality and purity takes a long time, therefore this nuclear transfer technology is very beneficial to generate a new line that could be useful to breed elite varieties. We had obtained around 200 fused carrots (cybrids), 12 cybrids were self pollinated and produced seeds. Selected progenies have been evaluated for horticultural characteristics and we have found new genetic lines that show better phenotypes.

Polymerase chain reaction (PCR) is highly utilized for QTL analysis, positional cloning of valuable genes, and molecular breeding in crop science. Usually those experiments handle DNA samples of many genotypes (up to several thousands). However, many DNA extraction protocols require longer time using harmful chemicals such as chloroform, phenol, and liquid nitrogen. Here, we introduce a new DNA extraction method for PCR with agarose/PAGE analysis from a diversity panel of rice genotypes identified with yield enhancing traits. This protocol consists of four steps including injection of extraction buffer (20 mM Tris-HCl pH9.5, 200 mM KCl, 2 mM EDTA) into the tubes containing leaf tissues and steel balls, and crushing tissues using Geno-Grinder without liquid nitrogen, sample incubation at 65°C, and then centrifugation for removing cell debris. After centrifugation the crude extracts directly used as template DNA for PCR. Through this protocol we could complete F1 hybridity test from approximately 2,100 plants that come from 96 cross combinations with 13 SSR markers. In addition, we tested the DNA quality by PCR amplification of high GC-rich region and large target size (-2kb). From these results our DNA extraction method produces enough DNA quality for PCR and is suitable for large scale molecular analysis from rice plants.

Although much effort has been made to find agronomically important loci in the soybean plant, extensive linkage disequilibrium and genome duplication have limited efficient genome-wide linkage analyses that can identify important regulatory genes. In this respect, recombination block-based analysis of cultivated plant genomes is a potential critical step for molecular breeding and target locus screening. We propose a new three-step method of detecting recombination blocks and comparative genomics of bred cultivars. It utilizes typical reshuffling features of their genomes, which have been generated by the recombination processes of breeding ancestral genomes. To begin with, mutations were detected by comparing genomes to a reference genome. Next, sequence blocks were examined for likenesses and difference with respect to the reference genome. The boundaries between the blocks were taken as recombination sites. All recombination sites found in the cultivar set were used to split the genomes, and the resulting sequence fragments were named as core recombination blocks (CRBs). Finally, the genomes were compared at the CRB level, instead of at the sequence level. In the genomes of the five Korean soybean cultivars used, the CRB-based comparative genomics method produced long and distinct CRBs that are as large as 22.9 Mb. We also demonstrated efficiency in detecting functionally useful target loci by using indel markers, each of which represents a CRB. We further showed that the CRB method is generally applicable to both monocot and dicot crops, by analyzing publicly available genomes of 31 soybeans and 23 rice accessions.

This experiment conducted to identify the changes of the response when white-back planthopper (WBPH, Sogatella furcifera), were inoculated in 10 days rice leaves after germination. We confirmed the difference between inoculated and uninfected plants by in the different time period (1day, 1 week, 2 weeks, and 3 weeks after inoculation). Breeding rice and WBPH maintained at 26∼28℃ with 60 % humidity. 3 leaves plants (TN1, Cheongcheong, and Nagdong) were inoculated with 2∼3 instars WBPH. Harvested rice plant samples were completely dried in dark condition and then samples were completely immersed in a solution of methanol for 3 days under darkness. Dissolving in water and then de-fatted three times with hexane. 100 ppm samples were applied to HPLC, eluting with acetonitrile and 0.1 % acetic acid by C18 (5ph column Agilant) and detected at 254 nm. We confirmed the difference of peak using LC/MS/MS (API-2000). The results showed that three weeks from the day of inoculation was increased at the molecular weight 118.1, 264.2 and 364.2.

Bt gene derived from the B. thuringiensis has been used for developing GM crops, and corn, cotton and soybean producing B. thuringiensis toxins have been on the market for last 16 years or so creating a huge GMO industry. One of the notorious pests in brassica crops is diamond backmoth (DBM). In order to protect the insect plague of crops from DBM, 4-5 billion dollars have been wasted annually for applying integrated measures in worldwide. Major prevention is use of pesticides that may build the contamination level of chemicals in the ground and this practice threats the environment and ecosystem. An alternative is to develop GM brassica crops and therefore we have developed GM cabbages resistant DBM using bt gene. Lots of T0 cabbages were tested for resistance and independent GM cabbages resistant to DBM were selected. Molecular analysis was conducted to find GM cabbage to hold one copy transgene and intergenic insertion. We found two independent GM cabbages as an event and those have been self-crossed for two generation. Also we are working the development of GM cabbage with different vector that contains bar gene as a selection marker.

VitE (tocotrienols and tocopherols) are micronutrients with antioxidant properties synthesized by photosynthetic bacteria and plants that play important roles in animal and human nutrition. A new mutant line, T1001-1, was isolated from in vitro mutagenized population by ionizing radiation and shown to have increased VitE contents. The total VitE content was 26% increased in the T1001-1 mutant seeds compare with cv. Dongan (wild-type). In addition, we showed that the mutant confers retarded seedling growth during the early seedling growth stage in rice. To study the molecular mechanism of VitE biosynthesis, we used the rice microarray to identify genes that are upor down-regulated in T1001-1 mutant. In addition, we identified differentially regulated pathway using MapMan analysis, which provides deep insight into changes in transcript and metabolites. Our results enhanced the transcription of genes involved in starch and lipid metabolism in T1001-1 mutant. To identify the molecular mechanisms of the events involving transcription factors in tocopherol accumulation, we compared the expression patterns of transcription factors. The AP2-EREBP, WRKY, C2H2 transcription factor were up-regulated, whereas the MYB family was down-regulated in T1001-1 mutant. Our results demonstrate change of important transcript in high level of VitE accumulating rice mutant.

Arabidopsis Fused kinase TWO-IN-ONE (TIO) controls phragmoplast expansion and interacts with the Kinesin-12 subfamily proteins that anchor the plus ends of interdigitating microtubules (MTs) in the phragmoplast midzone. Previous analyses of loss-of-function mutants and RNA interference lines revealed that TIO positively controls both somatic and gametophytic cell cytokinesis, however, knowledge of the full spectrum of TIO functions during plant development remains incomplete. In order to further characterize TIO functions, we expressed TIO and a range of TIO variants under control of its own promoter in wild type Arabidopsis plants. We discovered that TIO-overexpressing transgenic lines produce enlarged pollen grains, arising from incomplete cytokinesis during male meiosis, and showed sporophytic abnormalities indicating polyploidy. These phenotypes arose independently in TIO variants that abolished either gametophytic function or the ability of TIO to interact with Kinesin-12 subfamily proteins. Interaction assays in yeast showed TIO to bind to AtNACK2/TETRASPORE and plants doubly homozygous for kinesin-12a and kinesin-12b knockout mutations to produce enlarged pollen grains. Our results show that TIO dominantly inhibits male meiotic cytokinesis in a dosage dependent manner that may involve direct binding to acomponent of the canonical NACK-PQR cytokinesis signaling pathway.

Grain sorghum is the fifth most important crop grown in the world for either a major food crop or animal feed. It is important to identify the genetic diversity of sorghum genetic resources for cultivar development and evaluation of sorghum accessions in Korea. Two hundred thirty six SSR primer sets, which are evely distributed across the sorghum genome, were used to assess the genetic variation of 23 sorghum accessions with a US cultivar, BTx623. Results showed that SSR markers were highly polymorphic among the sorghum collections and the average alleles per locus were 3.15 with the average of 0.436 PIC (polymorphism information content) values. The sorghum accessions in this study were unequally separated and were clustered into 4 groups. The results showed that there was a sufficient SSR polymorphism with SSR primers used among Korean sorghum accessions, and the development of genetic map and marker-assisted selection for cultivated sorghum would be feasible with further studies.