Hemp (Cannabis sativa L.) is a dioecious plant, although monoecious plants are bred in some cultivars for fiber or seed production. Recently, hemp has received attention for medicinal use with some cannabinoids, including cannabidiol. Self-fertilization for breeding inbred lines is difficult because of dioeciousness and anemophily in hemp. This experiment was conducted to develop a self-fertilization method by forming female flowers and seeds from male plants of dioecious hemp. To induce the formation of female flowers on male plants, 500 ㎎ L-1 of ethephon was sprayed on plants at soon, seven and fourteen days after primordia formation. The plant ratio of female flowers formation and the number of harvested seeds were increased by ethephon treatment. Female flowers of male plants have 5 stigmas in contrast to the dual stigma of female 1plants. Male plant seeds were lighter and smaller than those from female plants. Although the germination rate was lower than that of normal seeds from female plants, the seeds from male plants germinated to grow seedlings. Thus, we suggest that hemp plants should be treated with ethephon at soon after primordia formation to induce the formation of more female flowers on the male plants.

본 연구는 시판되고 있는 효모의 종류에 따라 약주의 품질 특성에 미치는 영향을 보고자 하였다. 발효 완료 후 총산은 0.26%에서 0.40% 범위였으며, 가장 낮은 것은 La parisinne(red)로 발효시킨 약주였고 가장 높은 것은 EC1118 효모로 발효시킨 약주였다. 발효에 사용한 효모의 종류에 따라 약주의 아미노산도는 2.49-5.59 범위로 큰 차이를 나타냈는데, K1-V1116, La parisienne(black), La parisienne(red)로 발효시킨 약주는 아미노산도가 각각 5.59, 5.55, 5.34로 비교적 높았다. 반면에 Fermivin으로 발효시킨 약주는 2.49로 다른 효모로 빚은 약주에 비해 낮은 수치를 보였다. EC1118 효모로 양조한 약주의 경우, 발효 완료 후 환원당과 가용성고형물이 0.19% 및 7.17 °Brix로 낮아, 잔당이 적은 드라이타입의 약주제조에 적합할 것으로 판단된다. 본 연구에서 제조한 약주의 주요 유기산은 호박산과 젖산이었으며, 특히 La parisienne(black), La parisienne(red)로 발효시킨 약주에서 신맛보다는 감칠맛을 내는 호박산이 많이 함유되었다. 이것으로 아미노산도가 높고 감칠맛을 내는 호박산을 많이 생성하며 고온에서도 발효가 가능한 La parisienne이 탁·약주 발효에 사용하여도 무방할 것으로 사료된다. 또한, 주요 휘발성 성분은 아세트알데히드와 초산 그리고 이소아밀알코올이었으며, 그중에 아세트알데히드와 초산 함량은 본 연구에 사용한 효모의 종류에 따라 크게 차이가 있었다.

Endocrine disruptors have been concerned in toxicology but now challenged as physiological point especially concerned with exposing dose and period. In this study the low-dose chronic administration of di(2-ethylhexyl) phthaltae (DEHP) during reproductive period was examined to evaluate the possible roles. Adult male and female CD-1 mice were exposed to DEHP with drinking water containing 133 g/L and 1,330 ㎍/L DEHP in water according to OECD 433 guide line and sacrificed just after weaning. The weights of uterus and ovary were decreased by drinking of 1,330 ㎍/L DEHP water. There was not adverse effects on either accumulated mating rate and mating rate depend on estrus stage, pregnancy duration, and sex ration at birth. However, the accumulated rate of successful delivery and litter size were significantly high at 1,330 ㎍/L DEHP water. The number of epididymal sperm was significantly increased by drinking of 1,330 ㎍/L DEHP water. In addition, the number of follicles (primary, secondary, tertiary) were more many than control at 1,330 ㎍/L DEHP water drunk mother. Though further studies are needed to identify what are the mechanism of DEHP in folliculogenesis and spermatogenesis. From this study we firstly report the effect of low-dose chronic administration of DEHP with drinking could change the ovarian follicle population size and spermatogenesis rate. Put together, those finding is different from previous high-dose effects and suggest the physiological role of DEHP in gonads and uterus.

Bovine mammalian gland has biopotential in therapeutic protein production and could be used as a model in further lactation researches. In this study, we have isolated bovine mammary gland-derived epithelial cells (BMECs) from Korean Holstein dairy cattle and themselves show differential dynamic ability in in-vitro culture. BMECs enables to form lobulo-alveolar structure, express milk production related gene. Functional studies indicated that BMECs secret exogeneous antibacterial fragment-Bovine Lactoferricin B (bLfcin-B), which is inserted in PiggyBac system, and this bioactive fragment inhibits the growths of Escherichia coli and Staphylococcus aureus. These data demonstrated that BMECs open new scope in either bioactive fragment, heading to prevent the spread of mastitis or post-mastitis damage in dairy graze and could be an ideal bioreactor for antibacterial proteins.

This study analyzed the placement shape and correlation of green space focusing on anion that is one of curing substances. As its result, it was found out that the meteorological element becomes different and the generated amount of anion also gets different along such different meteorological element in case the shape of placing green space. As the result of analyzing the correlation with meteorological element , it was analyzed that it was the positive correlation in case of time, temperature and relative humidity and it was also analyzed that it was negative correlation in case of wind velocity and amount of light. But, in case of wind velocity, it was considered that the further complement research is required as the sampling distribution was shown as so biased by the windproof effect of the trees planted at the outskirts of green space in case of wind velocity. Based on th analyzed results as above, it suggested the model of generating anion by implementing multiple regression analysis such as y = -2462.383 + 0.304x1 x 72.746x2 x 7.315x3 x - 0.138x4 (x1; time, x2; air temperature, x3; relative humidity, x4; luminous intensity, R2; 0.691).

4-Nonylphenol (NP) is a surfactant that is a well-known and widespread estrogenic endocrine disrupting chemical (EDC). Although it has been known that the affinity of NP to ERs is low, it has been suggested that low-dose NP has toxicity. In the present study, the endocrine disrupting effects on reproduction, and the weight of gonads, epididymis, and uterus were evaluated with the chronic lower-dose NP exposing. This study was designed by following the OECD test guideline 443 and subjected to a complete necropsy. In male, NP had an effect on the weight of the testis and epididymis in both F0 and F1. In females, NP decreased the weight of ovary and uterus in F0 but not in pre-pubertal F1 pubs. Fertility of male and female in F0 or F1 was no related with NP administration. The number of caudal-epididymal sperm by body weight (BW) was not different between groups in both F0 and F1. Besides, the difference of the sperm number between generations was not detected. The number of ovulated oocytes was similar between groups in F0, but significantly decreased in NP 50 group of F1. The litter size and sex ratios of offspring in F1 and F2 were not different. The accumulated mating rate and gestation period were not affected by the NP administration. Those results shows that chronic lower-dose NP administration has an effect of endocrine disruptor on the weight of gonads and epididymis of F0 and F1 but not in reproduction. Based on the results, it is suggested that chronic lower-dose NP exposing causes endocrine disruption in the weight of gonad and epididymis but not in the reproductive ability of next generations.

Background : Korean ginseng is an important cash crop in Asian countries. However, plant yield is reduced by pathogens. Among the Ilyonectria radicicola-species complex, I. mors-panacis is responsible for root-rot and replant failure of ginseng in Asia. It is essential to find a way to reveal the existence of the pathogen before starting cultivation. Therefore, qRT-PCR method is developed to detect and quantify the pathogen in ginseng soils. Methods and Results : In this study, species specific Histone H3 primer set is developed for the quantification of I. mors-panacis. The primer set was applied on DNA of other microbes to evaluate its sensitivity and selectivity on I. mors-panacis DNA. Sterilized soil samples artificially infected by the pathogen in different concentrations were used to evaluate the ability of the primer set to detect the pathogen population in the soil DNA. Finally, the pathogen was quantified in many natural soil samples. The designed primer set was found to be sensitive and selective to I. mors-panacis DNA. In artificially infected sterilized soil samples, the estimated template using qRT-PCR was positively correlated with the pathogen concentration in soil samples (R2=0.94), disease severity index (R2=0.99), and colony forming unit (R2=0.87). In the natural soils, the pathogen was recorded in the most of fields produce bad yields with the range of 5.82 ± 2.35 to 892.34 ± 103.70 pg/g of soil. Conclusion : According to the presented results, the proposed primer set is applicable for estimating soils quality before ginseng cultivation. This will help in the disease management and crop protection in the future.

Background : Licorice has been used as a source of medicine and a food material in East-Asia. Recently, demand for licorice increased in market due to a growing interest in health. Thus we conducted breeding research to solve the problems associated with domestically cultivated licorice such as low productivity and low glycyrrhizin content. Methods and Results : We crossed European licorice (G. glabra L.; female parent) and Chinese licorice (G. uralensis Fisch; male parent) in the greenhouse in May 2007. In September 2007, crossed and germinated seeds were retrieved and sown in the greenhouse. In June 2008, stolons were separated from the F1 licorice seedlings and cultivated, resulting in 32 clonal lines of interspecific hybrids. Among them we selected good lines and then conducted the replicated yield trials (RYT) in 2012-2013 and local adaptability test (LAT) in 2014-2015. The results, GLYES9 showed that was elect of stem, oblong of leaf shape, red-brown of root color. Glycyrrhizin conten of GLYES9 (3.0%) was higher than G. uralensis (1.9%) at four regions from 2014 to 2015. GLYES9 was less than 10% in the desease of brown spot (G. uralensis was more than 30%). The root yield of GLYES9 was 4.31 ton per hectare, which was increased 193% compared with a check variety of G. uralensis. Therfore, we named GLYES9 as new cultivar ‘Dagam’. Conclusion : Depending on the above results, we have developed a new licorice cultivar ‘Dagam’ by the medicinal crop breeding team of National Institute of Horticulture and Herbal Science, RDA, in 2015. It showed brown spot disease resistant, high-glycyrrhizn content and high-yielding than colleted Glycyrrhiza spp.

Background : Chrysanthemum indicum L. is used in medicine, for bee, ornamental as multivoltinism plant resources. Since ancient times, Chrysanthemum indicum L. had been widely used as drug and tea. To diversity and increase the demand of Chrysanthemum, it is breeding for medicinal herb, tea and ornamental flower. Therefore size and shape of plant, color of flower have been used for cross breeding. CI2013 lines collected from Jeju have been used for landscape and ornament. and CI2010 lines collected from Sancheong have been used for medicinal herb tea. As a result, many new lines were developed. Therefore it was carried out to use as a date for new varieties through the characterization of good lines. Methods and Results : 7 lines were investigated and these plants were forstered and cultivated from Gyeongsangnam-do Agricultural Research & Extension Services (Hamyang). Breeding Lines were CI201001, CI201002, CI201005, CI201006, CI201303, CI201307, CI201401. The shape of CI201303 and CI201307 were round, plant height is low and width is wide, it may be used for landscape and ornament. As the size of flower in CI201005 was big, it may be used for medicinal herb tea. Conclusion : CI201303 and CI201307 lines were good for landscape and ornament because of round shape. CI201005 line was good for medicinal herb tea because of big flower.

Background : Cucuma longa L., in the family Zingiberaceae, is distributed in tropical and/or sub-tropical regions mainly in India and China. This species is commonly called tumeric, powder is used as medicinal herbs and/or flavor enhancer. It has been cultivated in southern region mainly Jindo. However, it might be possible to extend cultivation region due to rise in average temperature. In order to select superior lines, agronomic characteristics is commonly used. Because this is not the ultimate solution, the DNA marker approach has benefited the modern plant breeding. Therefore an easy approach by using one kind of primer have been developed from random amplification of polymorphic DNA sequences (RAPD) to discriminate effectively between different cultivars of Cucuma species Methods and Results : DNAs were extracted from the harvested roots of Cucuma sp. using DNeasy plant Mini kit (Qiagen, Hilen, Germany). These plants cultivated from GARES (Hamyang) and used for PCR amplification. The relative concentration of the extracted DNA was estimated Nano Drop ND-1000 (NanoDrop Technologies, Wklmington, De, USA) and final DNA concentration was adjusted to 5.5 ng/㎕. In this study 9 primer pairs were tested on 8 Cucuma sp. These primers showed polymorphism in Cucuma sp. The cluster dendogram showed that the similarity coefficients ranged from 0.68 to 0.87, CUR02 turned out to be CUR11, and CUR16 is similar to CUR17. Conclusion : These finding could be used for further research on cultivar development by using molecular breeding techniques and for conservation of the genetic diversity of Cucuma species. These data on polymorphism difference based on RAPD will be give us invaluable breeding information by selection of superior lines.

Sexual dimorphism is the most conspicuous difference between the sexes. This study examines possible sexual dimorphism and the relative growth patterns of morphometric characteristics in the marine medaka, Oryzias dancena for their potential to help differentiate between males and females of this species. The von Bertalanffy growth parameters estimated by a non-linear regression method were L∞=30.2 mm, K=3.22/year, and τ0=-0.05. All 18 characteristics measured showed a difference between males and females from 70 days after hatching. Each of these characteristics were significantly different between sexes (ANCOVA, P<0.05), and the ratio of standard length between sexes showed that males were larger than females for all five morphometric measurements. Fin length measurements were taken for 21 distances of anal fin and 7 distances of dorsal fin between landmarks. There were all differences for all dorsal fin rays between the males and the females and there is significant difference in 70 days after their hatch when the sexual dimorphism is presented. The significant difference (P<0.05) in fin ray for male and female was more greatly seen as they grow. Male marine medaka showed more rapid growth than females, with longer length, dorsal fins and anal fins. Differences in these characteristics will be useful during experiments when it is necessary to differentiate between sexes of marine medaka.

Background : The purpose of this study is to investigate the effect of the ridge and mulching cultivation and adapted sowing(planting)time in stable medicinal herbs production of Lithospermum erythrorhizon Siebold et Zuc. And it accomplished one’s purpose to GAP guide manual established standard method of cultivation technology, contribute to the enlargement of farm’s income. Methods and Results : Method of cultivation type with the ridge and covering material were conducted under two condition compose to open cultivation (level row : 120㎝ ridging, black polyethylene mulching) and plastic greenhouse cultivation (high row : 90㎝ ridging, non-woven fabric mulching). Sowing with Daehong varieties in April 17, transplanting July 25 by growing pot seedling for 40 days in 2015. Planting density were spaced 30㎝ apart in inter-rows 10 ㎝ apart intra-row. Fertilizing level of N-P-K-Compost (fermented mixed oil cake fertilizer) applied at 6-4-6-300 ㎏․10 a−1, 60% of basal fertilizer in March 14, 40% of top dressing were four times application in April 14 ～July 15. Plot design randomized block 3 repetition. Conclusions : Compared to level ridging on black polyethylene mulching open cultivation for growing plastic greenhouse with the high ridging non woven mulching cultivation, seed yields havesting 1.4 times, the dried roots yields increased in 0.7 times. Also, Growth characteristics by sowing time in April 16. compared to planting time in July 25. Length of stem and main root of above-ground, subterranean part growth increment rising highest. Seed and dried roots yields with increased by 71%, 30%. respectively.

Background : Chrysanthemum indicum L. is used in medicine, for bee, ornamental as multivoltinism plant resources. The purpose of this study was to evaluate methods of rooting promotion to make high quality medicinal plants, thereby increasing farm income. This study investigated the effects of different cuttage period, extraction site, shading degree, nursery tray for promoting cutting slips rooting in Chrysanthemum indicum L. Methods and Results : It is used New variety "Gamkuk 1" that were forstered in Gyeongsangnam-do Agricultural Research & Extension Services. Method of application with cuttage period were conducted under five condition; Around the middle of April, Toward the end of April, Early in May, Around the middle of May, Toward the end of May. Early in May plant length was longer than other cuttage period as 41.2%, 83.7% and are significant at significance level 0.05. Method of application with extraction site were conducted under three condition; 1 - 3 node, 4 - 6 node, 7 - 9 node. Leaf number in 1 - 3 node was more than other extration site as 19.4%, 33.6%. Also root length in 1 - 3 was more than other extration site as 10.5%, 23.2%. Method of application with shading degree were conducted under three condition; 50%, 70%, 90%. Plant length in 50 - 70% was longer than 90% shading degree as 23.8%, 24.2%. Also shading degree 50 - 70% had many root length and root number. Method of application with nursery tray were conducted under five condition; 72, 105, 128, 162, 200 tray. Plant length in 105, 128 tray was longer as 8.5 - 35.3% than other nursery tray and are significant at significance level 0.05. Conclusion : According to the results, Early in May, extraction site 1 - 3 node, shading degree 50 - 70%, nusery tray 105, 128 showed the highest growth on cutting slips root promotion in Chrysanthemum indicum L.

Background : Cordyceps militaris has been an wonder drug to anti-aging efficacy and called the three main drugs with ginseng and deer antler from the past. Cordycepin, cordycepic acid (d-mannitol) and adenosine are known as functional ingredients in Cordyceps militaris. Among them, cordycepin, the representative component, has been reported as antimicrobial substance containing immune enhancement, anti-cancer and anti-inflammatory effects. Methods and Results : After Cordyceps militaris produced from different types of medium mixed with 10-fold volume of purified water, the mixture were extracted at 70±5℃ for a hour and that extracts re-extracted using ultrasonics wave for 30 minutes. Qualitative analysis of the index component was determined by using the Q-TOF (A quadrupole time-of-flight mass spectrometer), and quantitative analysis was performed by using HPLC (high-performance liquid chromatography) with Xselect HSS T3 column (2.1 X 100 mm, 2.5㎛, Waters, USA) and ultrapure water and acetonitrile as mobile phase A and B. Detection column temperature, injection volume and the flow rate were 35℃, 2 μL and 0.3 mL / minute respectively. The cordycepin content of Cordyceps militaris produced from medium mixed with vegetable and animal ingredients higher than single ingredient. Moreover, through a variety of analyzes by varying the type and content of the medium additives, the cordycepin in Cordyceps militaris produced from medium mixed with animal ingredients highest. Furthermore, the cordycepin content of a fruit body was higher than those of the a mycelium. Conclusion : These results provide a method for producing an high cordycepin content of Cordyceps militaris as functional food ingredient.

Background : Recently, there is a urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. In order to develop ginseng varieties with such traits, systematic breeding program and comprehensive field studies are prerequisite. Methods and Results : ‘Cheonmyeong' seeds were collected in 2008 from the farmer field of Buyeo. Physiological investigation and propagation were conducted from 2009 to 2011. It was given the name 'Eumseong No. 8 through the observed yield trial from 2012 to 2013 and local adaptability was carried out from 2014 to 2015. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. Yellow-red leaf and pink berry at maturing stage were observed. The time of emergence, flowering and berry maturity of the ‘Cheonmyeong’ were faster than those of ‘Chunpoong’. Stem length of ‘Cheonmyeong’ was shorter than that of ‘Chunpoong’, whereas stem diameter was thicker than that of ‘Chunpoong’. Main root length was shorter but main root diameter is thicker than that of ‘Chunpoong’. Number of seeds of ‘Cheonmyeong’ was fewer than that of ‘Chunpoong’ but 1,000-seeds weight and stratification rate were higher than those of ‘Chunpoong’. The yield performance of this variety was 661 kg/10 a in local adaptability test for two years, which is 22% higher than that of ‘Chunpoong’. ‘Cheonmyeong’ showed strong resistance to phytophthora blight, mulberry mealybug and nematode and moderate resistance to alternaria blight. ‘Cheonmyeong’ did almost not occur yellow spot of aerial part and rusty skin of root, show moderate resistance at high temperatures. Conclusion : Our study demonstrated that ‘Cheonmyeong’ is an ideal variety with heavier root weight and enhanced stress resistance and contribute will enhance biotic/abiotic stress resistance and increase the farmers' income.

Background: Chrysanthemum indicum L. is used in medicine, for bee, ornamental as multivoltinism plant resources. Since ancient times, Chrysanthemum indicum L. had been widely used as drug and tea. From 2000, breeding began and the three varieties "Manhyang", "Geumhyang", Gamro" were developed so far. As demand has increased, growth traits of "Wonhyang" has been tested and fostered to report growth characteristics of "Wonhyang". Methods and Results: It is used New variety "Wonhyang" that were forstered in Gyeongsangnam-do Agricultural Research & Extension Services. After going through selection, proliferation and characteristics of CI0901, production performance test carried out in 2012~2013. As a result, it had named as "Gamkuk 4" in high quality, quantity and of strong in the disease. Local adaptability trial test carried out in 2014~2015. Conclusion: "Wonhyang" was a good growth in plant height, lengths of branches. Leaf color is light green, flower color is light yellow. Disease and pest resistance of "Wonhyang" is relatively better than "Manhyang". Since plant height is small and plant width is big, "Wonhyang" is available for medicine, food and landscaping. As a result of local adaptability trial test, Yield(131.1㎏/10a) of three region Hamyang,Hapcheon,Changnyeongis 10% higher than "Manhyang". Based on the results of this study, "Wonhyang" was to be registered for a new breed through the breed fostering council.

Background : The purpose of this study was to evaluate methods to high quality medicinal vegetables, thereby increasing farm income. This study investigated the effects of different covering material and weed eliminating on stable foliage production in Peucedanum japonicum Thunberg. Methods and Results : method of weed elimination with covering material were conducted under four condition compose to Non covering(4～6 times by manual weed control), Barley straw cutting covered with 700㎏․10 a−1, Rice straw cutting covered with 500㎏․10 a−1, Rice husks covered with 1,000㎏․10 a−1. Fermented mixed oil cake compost applied at 380㎏․10 a−1, 60% of basal fertilizer in March 14, 40% of top dressing were four times application in April 14 ～July 15. Sowing dates were March 25, 2015. Plants were spaced 15 ㎝ apart in rows 15 ㎝ apart with open cultivation. Conclusions : Rice husks covering < Barley straw covering < Barley straw covering cultivation this order, aerial part as a result were plenty amount of growth. Weed the rates was 12 to 29% lower incidence. Green leaf yields is uncovering control plot (915 kg․10 a−1) compared to 2% from covering rice husks, barley straw and rice straw covering increased to 18%, 20%, respectively.

Background : The purpose of this study was to evaluate methods to high quality medicinal vegetables, thereby increasing farm income. This study investigated the effects of different organic fertilizer and applicated cultivation on stable foliage production in Peucedanum japonicum Thunberg. Methods and Results : method of application with organic fertilizer were conducted under nine condition compose to control(non application), N-P2O5-K2O (20-12-10)㎏․10 a−1, Hyphal incubation compost(HIC) applied at 851㎏․10 a−1, Hangawi organic compost(HOC) applied at 547㎏․10 a−1, Fermented mixed oil cake compost(FMOC) applied at 380㎏․10 a−1, 60% and 40% of basal fertilizer in March 12, top dressing were four application in April 12, May 12, June 13 and July 12, respectively. Sowing dates were March 23, 2015. Plants were spaced 15 ㎝ apart in rows 15 ㎝ apart with open cultivation. Conclusions : chemical fertilizers < hyphal incubation compost < hangawi organic compost < fermented mixed oil cake compost application, top dressing than 60% in order of 40% additional fertilizer, aerial part as a result were so many such amount of growth as number of leaf per plant, etc., Green leaf yields is untreated control plot (875 kg․10 a−1) compared to 12% from using chemical fertilizers, HIC application 18% higher, HOC application 20% higher, and FMOC application increased to 28% of the most.

This study was conducted to develop a fast and efficient screening method to determine the quantity of fatty acid in peanut oil for high oleate breeding program. A total of 329 peanut samples were used in this study, 227 of which were considered in the calibration equation development and 102 were utilized for validation, using near infrared reflectance spectroscopy (NIRS). The NIRS equations for all the seven fatty acids had low standard error of calibration (SEC) values, while high R2 values of 0.983 and 0.991 were obtained for oleic and linoleic acids, respectively in the calibration equation. Furthermore, the predicted means of the two main fatty acids in the calibration equation were very similar to the means based on gas chromatography (GC) analysis, ranging from 36.7 to 77.1% for oleic acid and 7.1 to 42.7% for linoleic acid. Based on the standard error of prediction (SEP), bias values, and R 2 statistics, the NIRS fatty acid equations were accurately predicted the concentrations of oleic and linoleic acids of the validation sample set. These results suggest that NIRS equations of oleic and linoleic acid can be used as a rapid mass screening method for fatty acid content analysis in peanut breeding program.

Much effort has been expended to find agronomically important QTLs for improving soybean yield. However, the complexity of genome, such as genome duplication, limits the utility of genome-wide association studies and linkage analyses to identify genes controlling yield traits. We propose the variation block method, a three-step process for recombination block detection and comparison. The first step is to detect variations by comparing short-read DNA sequences of the cultivar to a reference genome of the target crop. Next, sequence blocks with variation patterns are examined and defined. The boundaries between the variation-containing sequence blocks are regarded as recombination sites. All the assumed recombination sites in the cultivar set are used to split the genomes, and the resulting sequence regions are named as variation blocks. The practicality of this approach was demonstrated by the identification of a putative locus determining soybean hilum color and known genes such as flower color gene. We suggest that the variation block method is an efficient genomics method for recombination block-level comparison of crop genomes. We expect that this method holds the prospect of developing crop genomics by bringing genomics technology to the field of crop breeding.