This study examined the quality characteristics of Makgeolli to investigate the availability of Korean sweet potato cultivars as alcoholic beverages. The following sweet potato varieties were used: Gogunmi, Daeyumi, Shingunmi, Shinyulmi, Shincheonmi, Jinyulmi, Jinhongmi, Jeungmi and Pungwonmi; their alcohol contents ranged from 12.20% to 14.20%, with the lowest value in Makgeolli made with Jeungmi and the highest value in Makgeolli made with Jinhongmi. The DPPH radical scavenging activity was in the range of 37.51~77.02%, with the lowest value in Makgeolli made with rice (control) and the highest value in Makgeolli made with Gogunmi. As a result of analyzing the aroma component of sweet potato Makgeolli, 27 kinds of aroma components were detected, and six kinds of alcohols, 13 kinds of esters, four kinds of acids, and four kinds of other compounds were found. Regarding the number of aroma compounds, Makgeolli made with Shinyulmi showed the lowest number with 14 kinds, while Makgeolli made with Pungwonmi showed the highest number with 27 kinds.

This study examined the nutrient components and measured the physicochemical properties of 23 Korean sweet potato cultivars. The proximate composition, free sugars, organic acids, and dietary fiber of sweet potato were analyzed and the water binding capacity, oil absorption and pasting characteristics were measured. The proximate composition was the highest in Happymi and was higher in colored sweet potato than in general sweet potato (p<0.05). The sucrose content was the highest among the free sugars in the general cultivars and yellow/orange colored cultivar. The major organic acids were oxalic acid, citric acid, malic acid, succinic acid, fumaric acid, and acetic acid. Oxalic acid and citric acid were high in the purple colored cultivars and malic acid was high in yellow/orange colored cultivars. Each total dietary fiber content of the general and colored cultivars was 7.51-13.94 and 13.04-16.97%, respectively, but there was no significant difference. The water binding capacity and oil absorption of Juhwangmi was high in all cultivars (p<0.05). The peak viscosity of sweet potato powder showed highest a significant difference of 12.50-1342 cP (p<0.05). The breakdown of Sincheonmi was 512, which was the highest value (p<0.05). The setback of Geonpungmi was significantly low, 6.0 (p<0.05).

Among several insect pests in the potato fields, Liriomyza huidobrensis, pea leafminer, is emerging as a new threat to potato plants. Adult females damage the host mesophyll cells host due to ovipositor probing. After egg hatching, the eclosing larva also damage the leaf by mining the mesophyll and causing tissue death. Despite the importance of leafminer in potato production, there is no information available regarding its resistance level to potato cultivars in Korea. Using choice test, 21 potato cultivars consisting of 11 early-maturing, 6 mid-maturing and 4 late-maturing cultivars were evaluated the resistance to pea leafminer in the greenhouse and field condition. In this test, significant differences for resistance were observed. High levels of resistance to leafminers were obtained from cvs. Namsuh, Seohong, Jayoung and Superior. These resistant cultivars might be useful in future breeding programmes.

감자 품종별 일반성분, 유리당, 유기산, 유리아미노산을 분석하였고 물결합력 및 oil 흡수력, 색도를 측정한 결과 감자 품종에 따라 영양성분 함량 및 이화학적 특성의 차이를 보였다. 조단백질 함량은 서홍이 높았고 조회분은 추강이 높았다. 감자의 유리당 함량은 sucrose, glucose, fructose 순으로 함유되어 있었으며 주 유기산으로는 oxalic acid, citricacid, malic acid, succinic acid, fumaric acid이었다. 감자 23품종의 필수, 비필수 아미노산 함량은 각각 60.33-550.91 μmol/100 g, 30.44-1,0998.58 μmol/100 g 범위였다. 감자 품종 중 대지가 물 결합력이, 자심이 oil흡수력이 높았고 특히 칩 가공용인 대서와 가원과 비슷하거나 낮은 oil흡수력 을 보인 추백, 조풍, 하령, 신남작도 지방함량을 줄일 수 있는 가공제품에 적합할 것으로 판단된다.

Fifty potato cultivars were screened for potato aphid, Macrosiphum euphorbiae Thomas infestation degree in the field. Aphid honey dew secretion and contents of foliar substances (glycoalkaloids, total nitrogen, Ca, K and Mg) of the cultivars were measured in the laboratory to analyze the correlation between infestation degrees and those factors. The number of aphids ranged from 4.1 to 31.4 per five leaves. The lower density (less than 5 aphids) was found on cvs. Jidose, Recent, and Sebago. The aphid secreted highest (40.3 droplets) and lowest (15.7 droplets) honeydew on cvs. Jopoong and Anco, respectively. Degree of infestation is positively correlated to glycoalkaloids and total nitrogen contents of the potato leaf.

Total of 36 sweet potato field soils were sampled to survey the occurrence of the root-knot nematodes (RKN). The 61% of sweet potato fields in Haenam, 40% in Iksan and 31% in Yeju were infested with RKN, respectively. Average population density of RKN was 324 juveniles per 300 g soil. The resistance screening of sweet potato cultivars against RKN was carried out by using clay pots in a greenhouse. Average temperature under ground 10 ㎝ in pot was 21.5℃ during the test. There was no difference in number of egg sacs among different inoculation methods, however the egg-inoculation method was easy for treatment and had stable for results. The multiplication ratio of Melioidogyne incognita differed from 6.3 times (Jeungmi) to 63.2 times (Yulmi) by sweet potato cultivars. There were no cultivars showing resistance to M. incognita, but Jinmi, Jeungmi and Borami had resistance to M. arenaria, M. hapla and M. javanica.

청동방아벌레((Selatosomus puncticollis Motschulsky) 유충에 의한 50종 감자(Solanum tuberosum L.) 품종의 피해정도를 검정한 전보의 결과를 바탕으로, 10개 품종(수미, 조풍, 남작, 대서, 대지, 세풍, 남서, Anco, Bintje, Denali)의 괴경피해율과 피해도를 포장과 실내에서 검정하였다. 또한 품종별 피해도 차이에 대한 원인을 구명하고자 괴경에 함유된 여러 가지 성분들(glycoalkaloids, 당, 전분, 전질소, Ca, K, Mg)의 함량을 측정하였다. 청동방아벌레 유충에 대한 10개 품종의 포장 피해괴경율은 19~72%로 높았다. 실내검정 결과 청동방아벌레 유충에 의한 피해구멍수는 남서 품종에서 많았으나, 수미, 대서, Anco, Bintje, Denali 품종은 상대적으로 적었다. 또한 방아벌레 유충에 대한 -chaconine, -solanine, -tomatine의 활성을 실내에서 검정한 결과, 2,500 ppm 농도에서 어떠한 활성도 관찰되지 않았다. 괴경의 glycoalkaloids 함량은 품종별로 차이가 많았는데, 수미품종은 18.83 mg%로 가장 많이 함유하였으나, 남작 품종은 6.39%로 가장 적었다. 괴경중 화원당과 총당 함량은 남서 품종에서 각각 0.71%와 2.95%였으나, 대지 품종은 0.26%와 1.77%였다. 전분 함량은 대지, 남작, Bintje 품종이 많았던 반면 조풍과 세풍 품종에서는 적었다. 괴경중 전질소, K를 가장 많이 함유한 품종은 Anco 품종이었고, Ca는 대서 품종에 Mg는 조풍 품종에 가장 많았다. 이러한 결과를 바탕으로 품종별 해충의 피해도와 저항성 관련 요인들간의 상관성을 분석한 결과, 청동방아벌레 유충에 의한 피해는 괴경중 전질소 함량과는 부의 상과(r=-0.71435*)이었으나, 괴경중 총당 함량과는 정의 상관(r=0.78018*)을 보였다. 이러한 결과는 해충종합방제 프로그램을 확립하고 또한 새로운 내충성 품종의 육성에 기초자료가 될 것으로 생각된다.

Three potato cultivars were prepared as slices and stored for 4 weeks at 5℃. Changes in Vitamin C content and other quality factors, such as color, pH, soluble solid and protein content were determined. Vitamin C content and L value decreased in three potato cultivars. Initial Vitamin C contents of three potato cultivars varied from 49.27 mg% in Sumi to 56.40 mg% in Namjak. Changes in L value showed that the tendency of browning in Daejima was slower than Sumi and Namjak. Changes in pH were small. Soluble solids and protein content increased and varied by cultivar. From the correlation analysis, correlation between browning degree and Vitamin C content was low in three potato cultivars.

Three potato cultivars, Sumi,Daejima and Namjak, were prepared as slices. They were dipped in distilled water for 20 seconds. The potato slices were packed in polyethylene bags and stored at 5℃. Browning degree, total phenol and chlorogenic acid contents and polyphenol oxidase (PPO) activity were measured. And the correlation analysis of browning parameters were conducted. The results were as follows. There were increase in browning degree, phenolic content and PPO activity during cold storage of potato slices with different cultivars. Among three cultivars, Sumi showed the highest browning degree, phenolic content and PPO activity and also showed the highest % increse of browning and PPO activity during cold storage. On the contrary, Daejima was the lowest. But Daejima showed the highest % increase in phenolic contents during cold storage. With Sumi, browning degree was significantly correlated with PPO activity and phenolic contents (p〈0.05). With Daejima and Namjak, a significant correlation was found between browning degree and PPO activity (p〈0.05). From the above results, enzymatic browning reactions of potato slices and factors affecting them were dependent on cultivar. Among the tested three cultivars, Daejima showed the lowest browning degree during cold storage and thus seems to be desirable for minimal processing.

This work was conducted to identify sweet potato [(Ipomoea batatas (L.) Lam.)] cultivars showing high yield and processing suitability in the Jeonbuk region of Korea. Shoot-slips (30 cm in length) of 14 cultivars were planted with a planting density of 75×25 cm on May 30, and cultivated with black film mulching. Vine elongation at 30 days after planting was significantly increased (> 90 cm) in ‘Dahomi’ and ‘Sinhwangmi’, and was excellent (> 250 cm) 120 days after planting in ‘Sinhwangmi’, ‘Shinyulmi’, ‘Daeyumi’, ‘Jinhongmi’, and ‘Yeonhwangmi’. The branch number per plant showed a dramatic increase in ‘Shinzami’ 30 and 120 days after planting. The leaf number per plant showed the highest increase in ‘Shinzami’ 30 days and in ‘Sinhwangmi’ 120 days after planting. Total weight, mean weight, and number of marketable tubers per plant were significantly higher 150 days after planting than that 120 days after planting. Marketable tuber yield at 120 days was high, over 2.5 ton/10a in ‘Daeyumi’, ‘Dahomi’, and ‘Jeonmi’, and was considerably increased, from 3.2 ton/10a to 3.5 ton/10a, 150 days after planting. Total weight of marketable tubers per plant and marketable tuber yield 120 and 150 days after planting had significant positive correlations with vine length and number of nodes 30 days after planting. Starch value was significantly higher 150 days after planting than that 120 days after planting. ‘Daeyumi’ and ‘Jeonmi’ had good growth vigor, high yield, and high starch content; ‘Dahomi’ also exhibited beneficial traits such as good growth vigor, high yield, and bright orange-colored flesh.

To obtain basic data on the effects of differences cultivation periods and methods on growth and development of sweet potato tuber. We investigated growth and development of six major cultivars showing different characteristics, such as dry type(Yulmi, YM; Jinhongmi, JHM), intermediate type(Pungwonmi, PWM; Hogammi, HGM), and purple type(Sinjami, SJM; Danjami, DJM). The average tuber weight of YM and JHM was 4.1 and 8.6 g respectively, 50 days after transplant. At 80 days, the weight of YM and JHM rapidly increased to 25.2 and 26.1 g, respectively. Finally, at 120 days, the weight of YM and JHM increased to 120.7 and 79.4 g, respectively. The average tuber weight of PWM and HGM was 13 and 3.3 g, respectively, 50 days after transplant. The development pattern of PWM showed a consistent increase in tuber weight during the cultivation period, an average weight of 104.2 g at 120 days. However, the tuber development pattern of HGM was different from that of PWM. The average tuber weight of HGM rapidly increased for 100 days after transplant and then showed no increase at 120 days. In case of purple type sweet potato, the average tuber weight of SJM consistently increased during the cultivation period, whereas DJM showed rapid increase in average tuber weight at 80 days after transplant. Korean consumers prefer small, round sweet potato approximately 100g in weight. Based on the results, YM, PWM and SJM are classified as early developing cultivars that can be harvested approximately 120 days after transplant. On the other hand, JHM, HGM, and DJM are classified as late developing cultivars that can be harvested approximately 130 days after transplant.

감자 수요를 확대하기 위해서는 소득 증가와 함께 소비자 의 관심이 증대하고 있는 신선편이식품으로 시장을 보다 더 넓혀 나가야 한다. 이를 위해서는 감자에 존재하는 유독 물질 인 glycoalkaloids에 대한 주의가 필요하다. 본 연구에서는 도 입품종인 대서, 수미와 최근 국내에서 개발된 하령, 고운, 홍 영, 자영 품종을 포함하여 국내 주요 24품종을 대상으로 부위 별 PGA 함량을 분석하였으며 그 연구 결과를 요약하면 다음 과 같다. 1. 총 PGA 함량(mg/100g·FW)은 하령(10.1), 수미(9.3), 홍영(7.3), 자영(6.9), 대서(4.8), 고운(3.4), 자심(3.1) 순으로 나타났다. 2. 공시품종의 껍질부위 PGA 함량은 전체 함량의 41 ~ 85% 분포를 보였으며, 국내주요 재배 품종에서 대서는 PGA 함량이 껍질(85%)에서 높고 육질 부위(0.7)에서 낮아 PGA 독성으로부터 가장 안전한 품종이었다. 3. 특히 고운, 자심 품종은 PGA 함량이 제일 낮아 껍질째 감자를 이용하기에 적절하며 중간모본으로 활용가치가 크다 고 판단된다.

Potato glycoalkaloids(PGAs) are potentially toxic to humans at high levels and current safety regulations have recommended that PGAs content in tubers of potato cultivars should not exceed 20 mg/100g·FW. Accordingly, it is important to determine the PGAs composition and levels on potato cultivars for food safty and the breeding for new cultivars with low levels of PGAs. The main aim of this study was to evaluate α-chaconine, α-solanine and total PGAs content in the peel and cortex portions in 24 cultivars including ‘Haryoung’, ‘Goun’, ‘Hongyoung’ and ‘Jayoung’, recently released by Highland Agricultural Research Institute. The total PGAs ranged from 3.1 to 10.1 mg/100g·FW. 75-94% of total PGAs was existed in the peel part of all cultivars. We selected two cultivars, which can be eaten wth the skin on tubers, and so used for soy sauce braised potatoes and baby potatoes for the rest area. These results will provide consumers and breeders with fundamental information about the content of PGAs in Korea major cultivars.

PGA 함량 정보가 없는 유전자원을 활용한 다양한 용도의 감자 품종 개발은 괴경 내 PGA 함량을 높이는 비의도적 결과를 초래할 가능성이 있다. 이러한 배경에서 신품종에 대한 정밀한 PGA 함량 분석은 감자의 식품안전성 제고와 PGA 저 함유 품종 개발을 위한 교배 모부본 확보차원에서 중요하다. 본 연구에서는 도입품종인 대서, 수미와 최근 개발된 하령, 고운, 홍영, 자영 4품종을 대상으로 괴경 부위, 저장기간별 PGA 함량변화를 분석하였다. 그 연구 결과를 요약하면 다음과 같다.

The newly developed varieties, Jayoung (violet flesh color) and Hongyoung (red flesh color) that harboring various anthocyanins and flavonoids in flesh colored potato are highly increase their interesting not only for food but also functional characteristics such as anti-inflammatory effects. Up to date, most of the molecular markers developed in potato are linked to disease resistance including late blight and PVY, nematode. A few markers linked to economically important functional materials such as anthocyanin biosynthesis are published. With the low cost and high throughput of NGS (Next Generation Sequencing) technology, numerous molecular markers are highly increased in may crops. Among the molecular markers, SNPs (Single nucleotide Polymorphisms) are most useful markers owing to their large numbers in inter and intra varieties in potato. Here we reported SNPs discovery from transcriptome sequencing data acquired from colored flesh potato cultivars, Jayoung and Hongyoung with white flesh color Atlantic. Total RNA was isolated from shoot in tuber after breaking dormancy about 2cm length. Short read sequence data were obtained form Illumina Hiseq2000 and the raw dat set were trimmed with Q socore over 20. Sequencing data were align to reference genome (Solanum tuberosum v4.03, http://potatogeomics.plantbiolgy.msu.edu). About 70% of sequence read were mapped int to reference genome. 139,050, 140,976 and 146,429 total SNPs were discovered in Hongyoung, Jayoung and Atlantic, respectively. All SNPs are mapped into the psedomolecules in reference genome by chromosome. SNPs are also analyzed with homozygous and heterozygous SNPs and genic and intergenic region. SNPs are compared with Potato Infinium 8K Chip data. SNPs found in candidate genes of anthocyanin biosynthesis were discovered. These SNPs information of flesh colored potato will be further analyzed for the allele mining for anthocyanin syhthesis and control region