Gamma irradiation has been used in several ornamental plant species to obtain the desired genetic variability. Commercially, ornamental plants with a rich variety of flower colors and uniform shapes are prized and in high demand. Irradiation technology is widely utilized to generate a high number of mutations, which helps introduce new, improved variants in comparison to the control plant. The main purpose is to promote well-adjusted species by customizing some specific features to expand on the desired parameter. Exposure to an optimum dose of gamma irradiation is crucial to ensure the most beneficial mutation density. The effects of dose rates are species-dependent, thereby affecting the probability of inducing favorable attributes, such that they are either not clearly exhibited or are disoriented during the gradual physical development of the plants. To obtain high-quality species within a very limited period, gamma irradiation may present an alternative method to selective screening with its combined application of molecular-based analysis to contribute to mutational changes in plant physiology. Here we review current literature that focuses on the effect of appropriate doses of gamma irradiation and the morphological, functional, and molecular objectives of such irradiation in ornamental plants.

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.

To develop a dwarf turfgrass (Zoysia japonica) cultivar with artificial mutation-induced breeding method, the wild type control "Gosan" plants were exposed to a 30 Gy gamma ray source in 2010. The mutant lines showing short height were selected from successive generations. One of the resulting dwarf lines obtained was registered under the cultivar name of “Halla Green 1” (2016). The dwarf phenotype of the Halla Green 1 includes a reduction of the height by 4.5-fold, an increase in leaf and third internode lengths by about 6- and 2.3-fold, respectively, compared to the Gosan, and approximately 2.4-, 3.8-, and 1.5-fold relative to the Zenith, respectively. In addition, the Halla Green 1 had a sheath of darker green coloring compared to the light green Gosan and Zenith. The leaf blades of Gosan, Zenith and Halla Green 1 were all light green, whereas their stolons were purple, yellow-green and light purple, respectively. Trichomes presented on both adaxial and abaxial surfaces of the Gosan’s leaves, and only on the adaxial side of the Zenith’s leaves, but none on the Halla Green 1 leaves. The Halla Green 1 exhibited sufficiently distinct morphological traits when compared with the wild type Gosan and Zenith that the dwarf phenotype enhances its commercial viability.

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.

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.

KAS360-22 종자에 1998년 250 Gy의 감마선을 조사하였다. 그 후대에서 미이라병에 저항성을 가지는 계통을 선발･육성하여, ‘원율’로 명명하고 2009년에 최종적으로 품종보호권을 출원 신청하여 2012년 등록 완료하였다. 원품종 KAS360-22의 종피색이 노란색인데 반하여 신품종 ‘원율’은 갈색을 나타냈다. 100립중은 재래종 KAS360-22이 17.2 g, ‘원율’은 27.5 g으로 종자무게는 증가하였으며, ‘일품검정콩’(27.4g)과는 별다른 차이를 보이지 않았다. 신품종 ‘원율’의 10a 당 수량은 미이라병 발병 조건에서 233.3 kg으로 재래종 KAS360-22 (24.9 kg)에 비교하여 10.6배 가량 높았고, 대조구 ‘일품검정콩’(121.4 kg)에 비교하여도 1.9배 가량 높아 밥밑용 콩으로 안정적인 수량 확보가 가능할 것으로 사료된다.

좀비비추 'White Edge'는 돌연변이 유기용 화학물질인 EMS(ethyle methane sulfonate)용액을 이용하여 돌연변이개체를 유기하고 그 중 잎 가장자리에 흰색의 테두리가 들어간 식물체를 선발하여 영양번식한 품종이다. 2003년에서 2005년까지 3차례의 특성조사를 거쳐 최종적으로 'White Edge'를 선발하였다. 3년간 특정검정을 실시한 결과, 'White Edge'는 잎 가장자리에 흰색무늬가 년 중 변함없이 균일하게 발현 되어 2007년에 종자산업법에 따라 국립종자원에 비비추 신품종 'White Edge'로 등록(품종보호 제 1880호)을 하였다. 잎의 무늬가 독특하여 및 화단용 반음지성 지피식물로 이용될 수 있는 매우 유용한 신품종이다.

NGS costs are decreasing rapidly, and beneficial application of the technology to plant genomics seems inevitable. Trying to interpret the agriculturally important traits like yield is actively in progress all across the globe. However, the current stage of bio-informatic technology as applied to the interpretation of agricultural trait appears not yet at a level of maturity to justify widespread plant genome sequencing for user-friendly molecular breeding. It is necessary to construct dense mutation block (DMB) based molecular breeding system for selecting plants with optimal agricultural performance; as well as for identifying useful quantitative trait loci (QTLs). Firstly, we screened and selected DMBs-specific INDEL markers obtained from SNV density profiles using 42 genome sequences of Korean cultivar and public sequences of 24 japonica rice cultivars. Secondly, we analyzed the genetic similarity between 288 Korean cultivars using 113 DMB-specific INDEL markers, which could differentiate on agarose gel by PCR. And we are going to integrate 360 INDEL markers up to 30 per each chromosome. Finally, we selected 40 founder lines considering the importance of the breeding, the purpose of use, and plant ecotype. To construct rice nested association mapping population we crossed each founder lines with the pollen of Hwayoungbyeo which was most commonly used in korean rice breeding program. F2 seed multiplication and generation iteration are ongoing.

좀비비추 'Blue Edge'는 돌연변이 유기용 화학물질인 EMS(ethyle methane sulfonate)용액을 이용하여 돌연변이개체를 유기하고 그 중에서 잎 가장자리에 진한 녹색무늬가 들어간 식물체를 선발하여 영양번식한 품종이다. 2003년부터 3년간 특정검정을 실시하였는데, 'Blue Edge'는 잎가장자리에 진한 녹색무늬가 년 중 변함없이 균일하게 발현 되는 것이 특징이다. 잎의 무늬가 독특하여 분화 및 화단용 반음지성 지피식물로 이용될 수 있는 유용한 신품종이다.

'Yellow Tiara'는 돌연변이 유기용 화학물질인 MMS(methyle methane sulfonate)용액을 이용하여 돌연변이 개체를 유기하고 그 중에서 연두색의 잎을 가진 식물체를 선발하여 영양번식한 품종이다. 2004년부터 3년간 특정검정을 실시하였는데, 'Yellow Tiara'는 잎 전체가 순수한 연두색으로서 년 중 색상에 변함이 없고 특성이 균일하게 발현된다. 잎의 색상이 독특하고 분화 및 화단용 반음지성 지피식물로 이용될 수 있는 유용한 신품종이다.

The world is facing a serious food and energy crisis. Plant mutation breeding has played an important role in overcoming this crisis and maintaining world stability. New techniques are required to achieve faster and more effective breeding. At RIKEN, we have developed a unique technology for mutation induction by using heavy-ion beams from particle accelerators at the RI Beam Factory. This development was achieved through an efficient synergistic link between agricultural science and accelerator physics. The use of ion beams for mutagenesis has a number of advantages: the approach has low exposure levels and high survival rates with high mutation rates, and it creates a wide variety of different mutations. Because heavy-ion beams provide a very high amount of energy, even a single ion is enough to significantly damage a gene – in fact, the beams have enough energy to break the double strand of the DNA. The technique is also very useful in producing mutants that lack just a single gene; multiple propagation technology can be used to convert these mutants into new cultivars. Examples of such breeds include ‘Safinia Rose’ (petunia), ‘Temari Bright Pink’ (vervena) and ‘Olivia Pure White’ (dianthus). The development period for producing new varieties is only 2 years. Over last decade, molecular biology has made great advancements through technological innovation. We use high-throughput DNA sequencing techniques such as next-generation sequence instruments and microarray technologies for analysis of gene mutations. Mutants have become more and more useful and important in modern genetic studies, enabling the discovery of genes that control important traits, and revealing the functions and mechanisms underlying their operations. The discovery of genes using mutants may lead to the emergence of a new field in biology, ‘Mutagenomics’.

재래종 서리태는 밥밑용 콩으로 한국인에게 선호되고 있으나, 숙기가 느려 수량성이 떨어지고 콩알이 커서 청소년들에게는 기피 경향이 있다. 서리태의 특성을 개량하고자 1994년 수집한 서리태 종자에 감마선 250 Gy를 조사하여 돌연변이 육종을 시도하였다. 그 후대에서 숙기가 빠르고 수량성이 높으며 콩알 크기가 작아진 유망 돌연변이 계통을 선발하여 ‘조생서리’로 명명하고, 2005년도에 품종보호권 및 국가품종목록등재 신청을 하였으며, 2008년도에 등록을

Encouraging progress in the mutation breeding has been achieved since a mutation induction has become increasingly important for a cultivar development for complex reproductive or propagating modes, the creation of new genetic resources, especially for crops with a narrow genetic base, and the use of mutants for a genomics study. In Korea, more than 35 cultivars have been released by using the mutation breeding method since the mid-1960s, and the released cultivars were mostly developed (76%) by exposing to radiations (gamma and/or X-ray). Most of the released mutant cultivars (74%) in Korea were food and oil seed crops, especially for improving agronomic traits such as yield, lodging tolerance, maturity, or functional compounds. Currently a high yield potential of cultivated crop cultivars is relatively less popular than before, but the expectation of value-added crops, from the farmer’s side, is in high demand. Accordingly, the mutation breeding program in Korea has assigned more resources to other crop species, including some flowering and ornamental plants. These flowering and ornamental plants are ideal systems for a mutation breeding because their favored traits such as flower color or shape or plant architecture can be visually monitored after a mutagenic treatment. Additionally, these plant species are genetically heterozygous and often propagated vegetatively, which allows for an isolation and selection of mutants within M1 generation. In Korea, a program for the development of potential cultivars of flowering and ornamental crops was launched with financial support from the Biogreen 21 project in RDA. Thisintegrated program which will be conducted by a diverse array of experts will focus on major flowering and ornamental crops in Korea such as rose, chrysanthemum, lily, carnation, orchids, and clover. The potential outcomes from the program will be new highly valued-added cultivars which will provide greater money gains to Korean farmers and lots of valued mutants used for a gene isolation of interest and reverse genetics or functional genomics. Appropriate strategies should be implemented to complete its goals successfully, which includes a)induction of a wide mutant spectrum, b)applications of new irradiation techniques, c)unraveling the complex genetic phenomena controlling mutant traits, and d)development of a mass production and an intensive export system for the developed cultivars.

"changhae" is a new Hibiseus variety developed by a mutation breeding by using a gamma ray irradiation. O dred seeds ofthe or iginal variety, "Suminokura", grown in a breeding field in the Namyangju, Gyeonggi Province were irradiatedwith a 100 Gy gamma ra