Recently, researches of molecular biology for the identification of root-knot nematode (RKN) species have been reported in plant quarantine. In this study, applicable and reproducible method to extract high quality genomic DNA from single nematode (Meloidogyne spp.) was developed. Also, the modified method was verified by DNA manipulation techniques such as PCR amplification and cloning. Single juvenile was floated in a drop of water and digested with proteinase K for 24 h. After that, DNA was extracted by using distilled water as extraction buffer. PCR amplification was carried out with universal primers spanning the internal transcribed spacer (ITS) region to distinguish species. When using the existing DNA detection method, quantification results showed that 42.86% of the deposited DNA was extracted. Whereas the modified DNA extraction method was increased to 100%. When PCR products test the direct sequencing using the ITS rDNA primers, it was also identified as M. javanica, M. incognita, and M. hispanica. Based on the studies conducted, the application of this modified method would be useful and efficient on plant parasitic nematode molecular assay.
Scutellonema. brevistyletum was collected at soil around the roots of oriental melon (Cucumis melo L. var. makuwa Makino) at Seongju, Gyeongbuk in Korea. Scutellonema brevistyletum resembles to S. sorghi in having large number of longitudinal lines (16-18 vs 16 in S. sorghi), but differs by the areolated at level of scutellum(not areolated in S. sorghi), shorter tail length(9.1-13.3㎛ vs 16.2-35.7㎛ in S. soghi) and not long intestinal overlap rectum. S. brevistyletum differs from S. unum in having shorter stylet (24.5-28㎛ vs 29-32㎛ in S. unum) and basal lip not having longitudinal striae.
The measurements of Ditylenchus acutus is similar to Fortuner & Maggenti’s 1987 D. acutus (Khan, 1965) except the body length was much longer (L=0.65-0.71 mm vs. L=0.39-0.50 mm) and body width was thinner (a=40-49.2 vs. a=22-28). In addition, Ditylenchus myceliophagus was recorded for the first time in Korea. Thus, both species were described in this paper.
Rotylenchus arsenjevi are reported for the first time in Korea. The Korean species differs slightly by having a hemispherical lip region and a slightly shorter tail than the original description (c=38.2-68.7 vs 36-41). Male was founded firstly from Korea and described. Geocenamus adakensis were collected a second time from Korea at a different locality and habitat. The measurements were compared with original description and the firstly collected specimen in Korea.
We amplified D1 and D3 expansion segments of the 28S ribosomal RNA from 10 Suanguina moxae populations found in Korea. The amplification of the D1-D3 expansion segments of 28S gene of all populations tested produced a single PCR product approximately 1.03kb in size, suggesting the lack of D1-D3 expansion region size polymorphism among populations. The secondary structure model of 28S expansion segments D2 and D3 for Subanguina Moxae was predicted based on free energy minimization with comparative sequence analysis and new sequence alignment was conducted based on predicted secondary structure model. The predicted model was compared with previous predicted models of plant and animal parasite nematode. This predicted secondary structure model will provide valuable information to allocate positional sequence homology and reconstruction of reliable phylogenetic trees.
차나무뿌리썩이선충(Pratylenchus loosi)이 국내에서 처음으로 전라남도 명암군과 제주도 남제주군의 차나무 뿌리와 주변 중에서 발견되었다. 차나무뿌리썩이선충의 두부주름은 2개이며 암컷의 길이는 433-646이고, a = 29.1-37.5, b = 5.1-6.4, c = 15.0-21.3, vulva (%) = 73.0-85.4였다. 수컷의 몸길이는 408-512 였으며 a = 36.1-40.0, b = 4.8-6.7, c = 17.0-19.0, spicule = 14.1-18.0였다. 구침의 길이는 11.6-18.0였으며, 측선의 갯수는 4개였다. 저정낭은 정자로 차 있으며, 모양은 둥근 고치모양 또는 직사각형 모양이다. 꼬리의 형태는 가늘고 끝이 둥글거나 뾰족하다.
환선충상과에 속하는 선충을 연구하던 중, 2신종을 발견하였다. Cnconemella hawangiensis는 C. paragoodeyi보다 훨씬 크고, 구침도 길고, 꼬리 주름 역시 다르다. Hemicycliophora parajugandis는 외부로 부풀어오른 구순부를 가지며 그것은 두부에 반원형으로 놓여 잇다. 그리고 두부측면은 안으로 밀렸다. 형태와 측정치는 H. juglandis나 H. koreana와 일치하였다. H. epichoroides는 한국 미기록종으로 보고된다.
나무좀인 Orthotomicus angulatus에서 천적기생선충인 Parasitylenchus orthotomici가 신종으로 기술되었으며, 적송에서 채집된 170마리의 표본에서 51.8%가 선충에 기생되어 있었다. 한 마리의 나무좀에서 발견된 선충수는 1~97마리였다. TEXF1/TEX세대의 기생율도 43.2%~52%로 높았으며 양지쪽과 음지쪽의 서식나무간좀에는 기생율에 일정한 경향이 없었다.