키가 큰 절화용 백합인 ‘Rialto’와 ‘Elodie’ 및 ‘Raizan’ 을 분화 및 화단용으로 사용하기 위하여 ancymidol과 uniconazole 및 paclobutrazol을 농도별로 관주처리 하 였다. 오리엔탈 백합인 ‘Rialto’의 경우, paclobutrazol을 처리한 구에서는 초장뿐만 아니라 잎과 꽃에 있어서도 변화를 관찰할 수 없었다. 그러나 ancymidol 처리구에서 생장은 농도에 관계없이 30% 이상 억제되었다. 한편 엽수나 개화수 등은 무처리구와 비슷한 경향이었다. Uniconazole 1mg·L−1 처리구에서 초장은 무처리구와 비슷한 경향이었으나 5와 10mg·L−1 처리구에서는 30% 정도 단축되었다. 아시아틱 백합인 ‘Elodie’의 경우 ‘Rialto’와 마찬가지로 paclobutrazol 처리구에서는 무처리 구와 유의차를 관찰할 수 없었다. 한편 모든 ancymidol 관주처리구에서는 초장이 무처리구보다 50~60% 단축 되는 효과를 나타내었다. 그리고 30mg·L−1의 ancymidol 처리구에서는 엽수가 감소하였으며 개화소요일수도 무 처리구보다 다소 지연되었다. Uniconazole 1mg·L−1 처 리구에서 초장을 제외한 모든 형질들은 무처리구와 유 사하였지만 5와 10mg·L−1 처리구에서는 무처리구와 유 의차가 인정되었다. 신나팔나리인 ‘Raizan’ 또한 상기 의 두 품종과 마찬가지로 paclobutrazol 처리구에서는 왜화효과를 관찰할 수 없었다. Ancymidol 처리구는 농도에 관계없이 초장이 무처리구보다 60% 이상 단축 되었으며 특히 30mg·L−1 처리구에서는 개화소요일수가 다소 지연되었다. Uniconazole 10mg·L−1 처리구에서 초장 은 약 26% 감소하였으나 다른 형질은 무처리구와 유의차 가 없었다. 결과적으로, ancymidol과 uniconazole의 관주 처리는 양적 형질에 큰 변화 없이 초장을 줄여 분화용 백합으로 사용하기 위해서 매우 효과적이었다.
본 연구는 감마선 조사 및 배양방법을 이용하여 유 용한 변이체를 선발하고, 그 특성을 관찰하기 위해 수 행되었다. 기내 신초수의 증식은 MS 배지 내에 NAA 0.2mg·L-1에 BA의 농도가 1.0mg·L-1로 증가할수록 양호한 반면 신초의 길이와 뿌리형성율은 감소되었다. 계대배양을 3회 수행한 후 온실에서 순화 및 삽목하였다. 감마선으로 조사된 총 370 개체들은 감마선의 조 사선량에 관계없이 토양이식 후 생존율이 97% 이상이 었다. 조사된 개체들 중 변이의 빈도는 감마선의 선량 이 증가할수록 높아졌다. 50Gy 조사구에서는 화색과 화형의 변이가 각각 28.2와 15.4%로 확인되었다. 화 색과 화형은 다양한 변화를 나타냈으며 줄기색 또한 변화되었다. 예를 들면 흰색에 옅은 자주색의 관상화는 흰색, 적자색, 노랑색 또는 연분홍색 등으로, 흰색이었 던 설상화는 연한 자주색이나 적자색으로 바뀌었다. 설 상화의 길이와 폭 및 화경의 크기가 달라진 개체 및 줄기에서 안토시아닌 색소가 제거된 개체도 관찰되었 다. 본 연구결과 국화 ‘Argus’에서 기내 배양체에 30- 50Gy의 감마선 조사에 의해 화색, 화형 및 줄기색의 다양한 돌연변이체를 선발할 수 있었다.
This study was carried out to compare the survival and mutation rates and mutation spectrum by gamma-irradiation on rooted and unrooted cuttings of three spray type (‘Lovelydia’, ‘Yellowbabe’, and ‘Haetsal’) and two standard type (‘Vital’ and ‘Aqua’) cultivars in roses. Two groups, rooted and unrooted cuttings were gamma-irradiated at 70Gy for 24 hours. The irradiated rooted and unrooted cuttings were planted in a greenhouse, and survival, mutation rates and mutation spectrum were investigated 30 weeks after planting, respectively. As a result, survival and mutation rates ofgamma-ray irradiated plants were 16.4%~50.8% and 0~5.1% for unrooted cuttings, and 39.4%~55.1% and 0.7%~7.4% for rooted cuttings, respectively. In conclusion, both survival and mutation rates were a little higher on rooted cuttings than on unrooted cuttings. However, when only survived plants after gamma-ray irradiation were considered, mutation rates were 0~10% and 1.8%~14.1% for unrooted cuttings and rooted cuttings, respectively, showing no significant difference. In addition, diverse variations on color and number of petals or shape of flowers were detected both in plants from rooted and unrooted cuttings, which indicated that there was no significant difference in mutation spectrum between two groups.
Kenaf (Hibiscus cannabinus L.) is an annual herbaceous crop of the Malvaceae family. Recently, kenaf is being used in many diversified applications such as pulp, animal feed, bioplastics and cellulosic biofuel etc. A new cultivar 'Jangdae' was developed by mutation breeding using irradiated with 300 Gy gamma-rays. Jangdae has a few distinguishable characteristics such as early flowering, high seed yield and palmate leaf, compared to wild type (Jinju). The fresh matter (FM) and dry matter (DM) yield of Jangdae are similar to those of Jinju, their seed yield (833.3 kg/ha) is approximately 4 times higher than that of Jinju. In addition, the FM and DM yield of Jangdae are 40% higher than those of early-maturing cultivar (C11). We performed the nutritive value of four kenaf cultivars (Jangdae, Jinju, C11 and Hongma300) at 100 day after seeding. The crude protein content of Jangdae, Jinju, C11 and Honma300 were 10.5, 11.0, 9.4 and 10.6%, respectively. The crude fiber, neutral detergent fiber and acid detergent fiber contents were no significant difference among the cultivars. Jangdae, which afforded both a high biomass and seed yield in South Korea, may be useful as potential source of feed and industrial materials.
A new soybean cultivar ‘Wonhyun’, was developed by mutation breeding technique using a 250 Gy gamma ray at Korea Atomic Energy Research Institute (KAERI) in 2010. ‘Wonhyun’ has black seed coat and much better agronomic performance than original variety ‘Paldal’. Their total yield (177.1kg/10a) is much higher than that of ‘Paldal’ (126.9 kg/10a). Also, 100 seed weight of Wonhyun was 27g compared to ‘Paldal’ (13.7g). Contents of 4 essential amino acids such as aspartic acid, glutamic acid, lysine, arginine and unsaturated fatty acid including linoleic and linolenic acid have much higher than ‘Paldal’. This cultivar is good for cooking with rice as improved functional ingredient soybean.
This study examined radiation damage and the optimal gamma-ray dose for mutation breeding in oat (Avena sativa L. cv. Samhan). The seed germination rate decreased as the dose increased over 500 Gy. The median lethal dose (LD50) was approximately 392 Gy. The median reduction dose (RD50) for plant height, tiller number, root length, and flash weight was 411, 403, 394, and 411 Gy, respectively. The optimal dose of gamma irradiation for inducing oat mutation appears to be in the range 300-400 Gy. We performed the comet assay to observe nuclear DNA damage induced by gamma-ray irradiation. This assay showed a clear difference with gamma-ray treatments. DNA damage increased temporarily 7 days after treatment depending on the dose, while no significant difference was identified in response to 300 Gy 30 days after the gamma-ray treatments. The growth characteristics of the M2 generation decreased as the dose increased over 400 Gy.
Seed color is an important factor affecting physiological and developmental process in wheat. One of the plant pigments, anthocyanins are a group of flavonoid compounds well known as pigments responsible for blue, purple, red, or yellow coloration of plant tissues. In this study, we investigated the pigmentation of purple and yellow color seed according to wheat grain developmental stages. The contents of anthocyanin and chlorophyll in the purple and yellow seeds were measured. Chlorophyll contents were changed similarly in both purple and yellow color seed, and no significant difference was observed between them. In purple color seed, the content of anthocyanin was significantly induced compared with yellow color seed. The individual anthocyanin components were investigated by ultra performance liquid chromatography (UPLC). Cyanidine-3-glucoside (C3G) and peonidine-3-glucoside (P3G) were detected as predominant anthocyanin in purple color wheat. To investigate whether structural genes in anthocyanin biosynthesis were involved in the trait differences between purple and yellow color seed, we examined the expression of anthocyanin biosynthesis-related genes (CHS, CHI, F3H, DFR, ANS, UFGT) and MYB transcription factor in developing wheat grains by using qRT-PCR. This study indicates that the expression of anthocyanin biosynthesis-related genes and MYB transcription factors correlate with anthocyanin levels of grain.
Ionizing radiation affects gene expression from plant genomes. To monitor the genome-wide transcriptional changes induced by three types of ionizing radiation, we used the rice RNA sequencing to identify genes that are up- or down-regulated by gamma rays (GAs), proton (PRs) and ion beams (IBs). The Oryza sativa jacalin-like lectin domain containing proteins (OsJAC1) gene was highly induced by GAs, PRs and IBs. OsJAC1 was selected based on the expression patterns of a genome-wide dataset of RNA sequencing. Many jacalin-related lectin genes have been shown to be associated with disease resistance, biotic and abiotic stress signaling. Therefore, we studied its expression pattern in response to different abiotic stress and phytohormone treatments. The expression patterns of OsJAC1 under two different abiotic stress conditions (salt and heat stress) and phytohormones (salicylic acid and methyl jasmonate) were examined. The transcripts of OsJAC1 were significantly induced in response to abiotic stress conditions, including salt and heat treatments. In addition, it was induced in response to the salicylic acid and methyl jasmonate treatments, respectively. To investigate the sub-cellular localization of OsJAC1, the gene was expressed as a fusion protein tagged with GFP, in tobacco leaf epidermis and examined under confocal microscope. The OsJAC1 was clearly localized at the nucleus. These results provide critical insights into the molecular functions of the rice jacalin-like lectin domain containing proteins as receptors of external signals.
The transposable element is a DNA sequence that can be changed its position within the genome, sometimes it can create or reverse mutations and altering the cell's genome size. Target region amplification polymorphism (TRAP) is a rapid and efficient PCR-based marker technique, which uses bioinformatics tools and expressed sequence tag (EST) database information to generate polymorphic markers around targeted candidate gene sequences. TE-TRAP is a new marker system which used terminal inverted repeat (TIR) instead of targeted candidate gene sequences. Sorghum holds a good potential plant organism for transposon tagging due to its small genome size, low amount of repetitive DNA and co-linearity with other cereal genomes, which allows the use of information derived from sorghum in other cereal grasses. IS2868 of sorghum accession was treated Gamma irradiation on seed. To define availability and utilization of TE-TRAP, twenty-one accessions were used to evaluate the genetic diversity and underlying relationships. One-thousand thirty-three TE-TRAP markers were amplified by thirty-one primer combination. Altogether, 712 (62.8%) markers were observed polymorphic segregation, whereas 421 (37.2%) showed monomorphic patterns. To estimate genetic differentiation of population by various gamma radiation doses, the analysis of molecular variance (AMOVA) was performed using 4 to 5 different radiation doses population of M1 sorghum individuals. This study and marker system will provide valuable information to assist radiation mutation breeding.
Space has many distinguishable characteristics from earth such as strong cosmic radiation, microgravity, supervaccum and weak magnetic field. For this reason, space environments can be used an efficient mutagen for plant breeding nowadays. To identify the affected genes by condition in space with outer space, Brachypodium seeds were placed in the Russia Segment (RS) Biorisk module of International Space Station (ISS). Brachypodium distachyon is a model system for temperature grass, because they represent the characteristics for annual winter grass. Seeds and organs of plants carried by satellite or spacecraft to space can be genetically mutated by exposing space environment. We performed a duplicated RNA sequencing to profile the differentially expressed genes. As a results, about 700 genes were upregulated and 250 genes were downregulated by cosmic environments, respectively. In the molecular function category, protein kinase and transcription activity related genes were upregulated. Among the many transcription factors (TFs), stress related TFs such as ERF, NAC and WRKY were differentially expressed in space exposed samples. In the future, their expression will be identified by using qRT_PCR.
‘Tocomi-1’, a new japonica rice cultivar derived from a 200 Gy gamma ray irradiation with high tocopherol content and red pericarp. The local adaptability test of MRXII-1001-1 was carried out from 2012 to 2014 and it was named as ‘Tocomi-1’ in 2014. This variety is medium matured with heading date of August 12 in honam plain area of Korea. This variety is about 80 cm tall culm length and 106 spikelets per panicle. Its 1,000 grain-weight of rice seeds is 25.4 g. The yield potential of this variety is about 5.15 MT/ha in local adaptability test for three years. This variety exhibited greater seed longevity than the Donganbyeo, indicating a crucial role for tocopherols in maintaining viability during quiescence, and displayed faster seedling growth during the early growth stage. Tocopherol contents was 50% higher than the Donganbyeo. To study the molecular mechanism underlying vitamin E biosynthesis, we examined the expression patterns of seven rice genes encoding vitamin E biosynthetic enzymes. Accumulation levels of the OsVTE2 transcript and OsVTE2 protein in the ‘Tocomi-1’ were significantly higher than in the Donganbyeo. Sequence analysis revealed that the ‘Tocomi-1’ harbored a point mutation in the OsVTE2 promoter region, which resulted in the generation of MYB transcription factor—binding cis-element. These results help identify the promoter regions that regulate OsVTE2 transcription, and offer insights into the regulation of tocopherol content in ‘Tocomi-1’.
This study was carried out to determine the amount of lignin, cellulose, and hemicellulose in six kenaf cultivars during different harvesting stages. Three mutant cultivars (Jangdae, Jeokbong and Baekma), two original cultivars (Jinju, C14), and one Chinese cultivar (Auxu) were planted on May 14, 2013. Four harvesting times were made at intervals of 20 days from 15 July to 16 September, 2013. The overall growth characters of mutant cultivar ‘Jeokbong’ such as plant height, stem diameter, flowering time, and dry mass were similar with those of the original variety. The mutant cultivar ‘Baekma’ occurred 10-day late flowering in comparison with the original variety and also displayed higher dry mass than the original variety. Jinju, Auxu and Jangdae, mid-late maturing kenaf cultivars, had high dry weight compared to early maturing cultivars such as Jeokbong, Baekma and C14. In all cultivars, the lignin contents were increased by a late harvest. The Mid-late maturing kenaf cultivars showed high lignin content in comparison with those of the early maturity cultivars. There were no significant differences of cellulose, and hemicellulose content between the cultivars, however cellulose content in stems of these kenaf cultivars were significantly decreased by a late harvest. These results may provide valuable information to assist the parental selection of kenaf breeding.
Rose (Rosa Hybrida Hort.) are of a high symbolic value and a great cultural importance in different societies. They are widely used as garden ornamental plants and as cut flowers. For the induction of mutation, gamma-rays are widely used as a mutagen. This study was carried out to establish a system for mutation breeding by irradiation of gamma-ray in rose. The rooted cuttings of five cultivar roses (Lovelydia, Vital, Aqua, Yellowbabe and Haetsal) are grown by in a greenhouse. They were two difference treatment (Before rooting gamma-ray irradiation, After rooting gamma-ray irradiation) were exposed to dose of 70 Gy using a 60Co gamma-irradiator (150 TBq of capacity ; ACEL, Canada) at the Korea Atomic Energy Research Institute. The irradiated plants were planted in a greenhouse, and investigated survival rate, mutation rate, flower buds number, and shoot length were planted after 80days. The two treatments of and growth characters was significantly reduced to 20% to 40% compared with the control. In addition, survival rate and mutation rate were ‘after rooting γ-ray irradiation (37.4~67.3% and 0.5~5.6%)’ higher than ‘before rooting γ-ray irradiation (18.3~50.8% and 0.3~3.4%)’. Mutation types were solid type, chimeric and mosaic petal mutants with various colors were induced from five rose. These results indicate that efficiency of mutation induction in rose by gamma-ray irradiation on petal colors and petal shapes in two difference treatment with rooted cutting system.
Kenaf (Hibiscus cannabinus L.) native to Africa can be used as fiber, food, feedstock and bio plastic. This study was carried out to evaluate the mineral, amino acid and vitamin contents of six selected kenaf cultivars which are enable to produce seed under Korean circumstance. The leaves of three mutant cultivars (Jangdae, Jeokbong and Baekma), two original cultivars (Jinju, C14) and one Chinese cultivar (Auxu) were harvested at flowering time. Mineral components of kenaf leaves, such as calcium, potassium, and mineral, did not showed significant differences among the cultivars. As major amino acids including proline and phenylalanine, significant differences were found in these kenaf cultivars. The Auxu cultivar contained the highest amount of essential amino acid (Phenylalanine, Leucine, Isoleucine, Valine, Methionine and Lysine). The amount of vitamin displayed significant differences such as vitamin E and vitamin K among these cultivars. Especially, Jangdae cultivar contained the highest amount of vitamin E and vitamin K. Thus, these data suggested that Jangdae and Auxu is the most desirable cultivar containing high amount of vitamin and amino acid.
Anthocyanin, a group of purple or reddish flavonoids, have been recognized as health-promoting functional food ingredients due to antioxidant activity. For this reason, plant breeders are trying to increase the anthocyanin contents using methods such as classical breeding and biotechnological approaches. To broaden the mutants population, seeds of colored wheat variety (K4191) were irradiated by using 250 Gy gamma irradiation. Individual 968 M4 plants were grown in Korea Atomic Energy Research Institute field. Many mutant phenotypes were shown: seed color variation, abnormal spike shape, awning formation, heading and ripening time, plant height, ripening period, super dwarf, etc. To identify the inheritance traits of colored-wheat, individual lines were maintained the spike base classified by generation. Characteristics per spike and plant were piled up to construct for mutant database. In the future, fixed descent will be analyzed the anthocyanin contents or other phytonutrients by ultra-performance liquid chromatography (UPLC). Expression of seed color-related transcription factors and anthocyanin biosynthetic pathway genes will be examined.
To define whole genome-level of structural variation by ionization energies and radiation doses in plant, the seeds of Ilpum rice cultivar were acutely irradiated with gamma rays (100Gy, 200Gy, and 400Gy) and ion-beams (20Gy, 40Gy, and 80Gy), respectively. Six M1 rice plants were re-sequenced by Hi-Seq2500 with Ilpum cultivar as control. The average sequencing coverage of the individuals was 10.6X, and the average mapping rate to the rice reference genome (IRGSP-1.0) sequence was 96.95%. The individual plants were irradiated with gamma-400Gy and ion-50Gy had highest variation of SNP with 471,837 and 469,147, respectively. The number of insertion/deletion was 77,500 and 77,106, the synonymous and frame-shift were 7,859 and 7,763 in above two individuals. Although high genome variation shown between Ilpum cultivar and irradiated individuals, there were non-correlation between number of variation and radiation doses. However, five individuals, except ion-20Gy, showed 33 common variant blocks (CVBs) spanning 6 Mb in whole rice genome (1.6%). The CVBs were distributed on 12 rice chromosomes, Chromosome 6 had biggest CVB (5 blocks, 1.3Mb), whereas chromosome 9 had smallest CVB (0.01Mb). Total five hundred fifty one genes were in CVBs which can regard radiation sensitive genes or may be regarded as radiation hot spots in rice genome. This study will contribute to the improvement of the radiation mutation breeding research in genetic and genomic aspect.
Exposure to ionizing radiation is regarded as a kind of abiotic stresses that can change the expression of genes in living organisms. This study aimed on investigating the variations in gene expressions induced by two different types of irradiations with different doses, which were low linear energy transfer (LET) gamma rays (100, 200, and 400 Gy) and high LET ion-beams (20, 40, and 80 Gy) on rice. RNA sequencing was carried out using the Illumina HiSeq-2500 platform. The average amount of reads were 4.8 Gb per individual, and 5 to 8% of the reads were removed after quality control. More than 90% of the RNA-seq reads were mapped to the rice reference genome sequence (IRGSP-1.0). A total of 247 differentially expressed genes (DEGs) were identified by comparison of the gene expression levels between the wildtype and the irradiated individuals. The 247 DEGs were divided into five modules and 27 intra-modular hub genes were found using the weighted correlation network analysis (WGCNA) method. The MEturquiose module had the most number of genes with 75 related to carbohydrate and small molecule metabolic processes. The co-expression network reconstructed using ARACNE (algorithm for reconstruction of accurate cellular networks) showed specific up- or down-regulation of the genes in each module according to the types and doses of radiation. This study will contribute to understanding the gene expression responses to ionizing irradiation.