A survey was conducted to find out the major plant parasitic nematode in Chrysanthemum morifolium fields in Korea from May to June in 2005. A genus of Pratylenchus was determined as the most important plant parasitic nematode based on analysis of total 50 samples from 8 cities of chrysanthemum field. Pratylenchus showed 86% occurrence rate and average numbered 1,095 per 200㏄ soils and Ig root. Five Pratylenchus isolates, "Muan", "Masan", "Tean", "Gumi", "Jeongup", were selected for the molecular identification of the species of Pratylenchus, and ITS and D3-28S ribosomal DNA were amplified by PCR. For the ITS, only" Muan" isolate was differentiated by total 1 kb PCR amplification, which was 200 bp larger than all the other isolates. There was no size variation in amplified D3-28S rDNA and all isolate represented approximately 320 bp of PCR product. Sequence data of D3-28S rDNA were analysed by MegAlign program in DNASTAR software and phylogenetic tree was constructed. Sequence homology was 100% between "Gumi" isolate and "Tean" isolate and "Jeongup" isolate was also close to these isolates by 99.7% sequence homology. "Gumi", "Tean" group and "Jeongup" isolate were determined to be closely related to Pratylenchus vulnus by 96.7% and 96.3% similarity in respectively. D3 sequence of "Masan" isolate was 100% identical to P. penetrans, and "Muari" isolate showed 99.7% similarity to P. brachyurus. This result was congruent with the branch divergence pattern shown in phylogenetic tree.

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.

살선충제 2종(카두사포스, 포스치아제이트)을 땅콩뿌리혹선충(Meloidogyne arenaria)이 감염된 참외 재배 포장에 정식 전처리(전처리)및 재배중 처리(후처리)하고(각 1.8 g a. i./6), 이들의 뿌리혹선충 방제효과, 참외 수량에 미치는 영향 및 참외 과일내 농약잔류량에 대하여 비교 조사하였다. 살선충제가 뿌리혹선충 밀도에 미치는 효과는 5월에 가장 뚜렷하였다. 살선충제 처리구의 선충밀도는 무처리구 밀도의 10-65%이었으며 살선충제 중에서는 포스치아제이트(P=0.003)가, 처리방법에서는 전처리+후처리에서 효과가 높았다(밀도 90% 감소). 살선충제 처리구는 무처리구에 비하여 5월 수량은 평균 23%(11-38%), 6월 수량은 평균 39%(2-65%), 총수량으로는 평균 31%(12-46%)가 증수되는 경향으로 유의성은 낮았으나(P ＝ 0.085) 수량차이는 많았다. 카두사포스는 과일내 농약 잔류량이 0.008ppm이하로 후처리에 문제가 없었으나 포스치아제이트는 후처리 약 30일 후 참외 잔류허용 기준치(0.2ppm)를 초과하는 0.26ppm이 검출되었고, 그 외의 기간에 수확한 참외에서도 0.12ppm이상 높게 검출되었다. 살선충제 후처리에 의한 뿌리혹선충 방제법은 농약잔류위험성, 후반기의 낮은 참외 가격, 농약 비용, 안전농산물에 대한 소비자의 요구, 휴경 효과 등을 종합적으로 고려할 때 바람직하지 않은 것으로 생각된다.

국내 고추 19품종을 이용하여 성주 참외 재배지역에 가장 많이 분포하고 있는 두 종의 뿌리혹선충, Meloidogyne arenaria와 M. incognita에 대한 저항성을 검정하였다. M. arenaria 에는 검사대상 고추 품종 모두가 저항성이었으며, M. incognita에는 품종별로 차이가 있었다. 즉 농우꽈리풋고추와 청옥고추는 감수성이었고, 알찬고추, 대왕고추, 진미고추, 조풍고추, 태양건고추, 한샘꽈리풋고추 등은 중간 저항성이었으며, 공공칠고추, 그린 No. 500 피만고추, 다홍건고추, 마니따고추, 신바람고추, 퍼팩토고추, 한마음고추 등은 강한 저항성으로 나타났다. 이상의 결과로 미루어 참외재배지의 뿌리혹선충 피해가 심한 포장에는 6월경 참외를 수확한 후, 공공칠고추, 그린 No. 500 피만고추, 다홍건고추, 마니따고추, 신바람고추, 퍼팩토고추, 한마음고추 등을 재배함으로서 뿌리혹선충의 밀도를 감소시킴과 동시에 고추 생산으로 부가소득도 가져을 수 있을 것이다.

1995년 전국 8개도 37개점의 밭토양으로부터 분리한 52균주의 선충 포식성곰팡이를 이용하여 실내 및 온실에서 부식성선충과 뿌리혹선충을 이용하여 포식력을 비교하였다. 실내검정에서 부식성선충에 대하여 91% 이상의 포식력을 보인 균주는 51균주였고, 부리혹선충에 대하여는 26균주였으나, 온실 검정에서는 81%의 포식력을 보인 균주가 3균주로 온실검정과 실내 검정간 상관 유의성은 없었다. 선발된 3균주는 부식선충 및 뿌리혹선충에 대하여 실내 및 온실실험에서 모두 높은 포식력을 나타내었다. 이 실험으로 미루어 볼 때, 천적 포식성곰팡이 선발 시험은 반드시 포장 조건과 가장 유사한 상태에서 실시되어야 할 것으로 보인다.

국내 콩씨스트선충의 race 분포를 규명하기 위해 전국 8개도 21개 지역으로부터 선충을 채집하여 검정한 결과, 4종류의 race가 발견되었은데, 그중 race 3(48%)이 가장 많았으며 race 5(24%), race 1(19%),race 6(9%) 순이었고 지역별 차이는 없었다. 국내포장에 서식하는 콩씨스트선충 집단중 약 33%는 저항성품종으로 알려진 Pickett를, 약 43%는 PI88788을 가해할 수 있는 virulence gene을 가지고 있었는데, Peking과 PI90763은 모든 씨스트선충 집단에 대해 저항성으로 나타났다. 국내 콩씨스트선충 저항성 품종 육성에는 Peking이나 PI90763을 교배모본으로 하여 race 5와 6에 대한 저항성 품종을 육성하는 것이 바람직할 것으로 보인다.

To survey the incidence of plant-parasitic nematodes, 187 soil samples from leguminous plant fields in Chungnam province, Korea were assessed from June to August 2018. As the result, four nematode genera ─ the cyst nematode (Heterodera spp.), root-knot nematode (Meloidogyne spp.), root-lesion nematode (Pratylenchus spp.), spiral nematode (Helicotylenchus spp.) ─ were detected. Among them, the incidence of cyst nematode was the highest in Taean (73%) and lowest in Hongseong (10%). The cyst nematode was detected from the adzuki and kidney bean fields as well as soybean fields. The incidence of cyst nematode in upland fields was higher than in paddy fields. In addition, the extracted cyst nematodes consisted of two species, which was identified as Heterodera glycines and H. sojae. The incidence of H. glycines (22%) was higher than H. sojae (10%), and a few of the fields (5%) was mixed with two cyst nematodes. This result suggested that we should consider that the cyst nematode is the major plantparasitic nematode when controlling the nematodes in soybean fields in Chungnam province.

To identify four cyst nematodes (Heterodera schachtii, H. trifolii, H. glycines, H. sojae) that are economically important plant-parasitic nematodes in Korea, restriction fragment length polymorphism (RFLP) by 8 endonucleases (PstI, VspI, AlwI, RsaI, MvaI, EcoRI, Eco72I, Hinf I) was performed based on sequence difference of mitochondrial DNA cytochrome c oxidase subunit I (COI) gene. As a result, species-specific DNA band patterns by RsaI endonuclease were observed in H. schachtii. The specific patterns was in H. trifolii by 3 endonucleases (VspI, AlwI, Hinf I), and was in H. glycines by Hinf I. While, H. sojae was not digested by 4 endonuclease (VspI, AlwI, RsaI, Hinf I). This study showed that four cyst nematodes could be distinguished using RFLP by 4 endonucleases (RsaI, VspI, AlwI, Hinf I) based on the sequence difference of COI gene.

Background : Korea's agriculture has been forced to change due to the decline in agricultural population, the aging of the population and the conclusion of the Convention on Biological Diversity. Thus, agriculture is seeking to develop into a sixth industry. For this reason, it is necessary to find high-function alternative plant resources for health promotion to meet the changes in national needs for agricultural products. The adventitious roots culture of wild mountain ginseng is the raw material of food code that produced by the biotechnology technique. introduced in the culture of the plant, which is the only way to use a raw material of food. Therefore, in order to increase the yield of ginsenoside in adventitious roots culture of wild mountain ginseng, ginsenoside precursor was treated and ginsenoside contents were analyzed. Methods and Results : In order to investigate effect of precursor treatment on the production of ginsenoside in adventitious roots culture of wild mountain ginseng, 5 g of adventitious roots culture of mountain ginseng were cultured in liquid SH media supplemented with 2 ㎎/l IBA, 3% sucrose for 8 weeks, which was co-cultured with β-sitosterol and Squalene (0.0625 to 1 mM) or without. Determination of 17 ginsenosides contents of each extract was carried out by HPLC. Rb3 was accumulated by only β-sitosterol, also it increased production of total ginsenoside in the cultured ginseng roots at a concentration of 0.125 mM, which was 2.47-fold higher than that in the control (78.13 ㎎/g of extract). Conclusion : These results are an important to improve the production yield of ginsenoside in adventitious roots culture of wild mountain ginseng, and they provide an opportunity for development of adventitious roots culture of wild mountain ginseng in dietary health supplement and pharmaceutical industries.

Background : Even though Kalopanax septemlobus has been used as a traditional crude drug and a dietary health supplement, the wild or cultivated sources of this plant are not economically feasible. Methods and Results : In this study, a cell suspension culture of K. septemlobus using friable calli was established to make source sustainable. A cell suspension culture of K. septemlobus was incubated during 15th day and reached the maximum capacity of saponin production after day 6 (0.42㎍/㎎ of fresh weight). To investigate the effect of elicitors on the product yield of saponins in the K. septemlobus suspension culture, we treated methyl-jasmonic acid and coronatine (COR), which are known as signal molecules. COR positively regulates the total saponin production in the cell suspension of K. septemlobus at a concentration of 1 μM compared with the mock-treated control. Furthermore, the expression of beta-amyrin synthase (KsbAS) was induced by elicitation of COR. Consequently, oleanane-type triterpene saponins, oleanolic acid (2.369 ± 0.98 ㎍/㎎ of extract) were accumulated by only COR. Conclusion : From the above results, COR is an efficient elicitor for inducing saponin biosynthesis in a K. septemlobus suspension culture. Gene expression pattern and analysing precursor of triterpenoid saponin indicate that major target gene of COR in K. septemlobus suspension culture is KsbAS.

본 연구에서는 B16 악성흑색종 세포에서 디펩타이드(dipeptide)의 멜라닌생성 저해 효과를 연구하였다. 실험결과 WV (트립토판-발린), WM (트립토판-메치오닌), CQ (시스테인-글루타민)는 멜라닌 생성을 농도 의존적으로 감소 시켰다. 그러나 디펩타이드는 멜라닌 생합성과정의 속도 조절 단계 효소인 타이로시네이즈(tyrosinase)의 활성을 직접 감소시키지는 않았다. 따라서 타이로시네이즈의 발현양상을 조사하였고, 실험 결과 α-MSH가 유도한 타이로시네이즈 발현이 WV, WM, 그리고 CQ에 의해 억제되었다. 그러므로 WV, WM, 그리고 CQ가 타이로시네이즈의 억제성 조절 (down-regulation)을 통해 멜라닌 생성을 감소시킨다고 제안될 수 있다.