Three free-living marine nematodes (Desmoscolex (Desmoscolex) max Timm, 1970, Daptonema longiapophysis Huang and Zhang, 2010, and Pseudosteineria sinica Huang and Li, 2010) were newly recorded in Korea. Desmoscolex (D.) max was found from subtidal coarse sediment around Wangdolcho in the East Sea. It was characterized by the presence of untypical setae arrangement, obviously elongated triangle-shaped head, long hairy cephalic setae, a long naked tail spinneret, and the absence of peduncle at the base of somatic setae. Daptonema longiapophysis was obtained from intertidal sandy sediments in the southern coast of Korea. It was characterized by the presence of setiform labial sensilla, spicules with a projection on both sides, and gubernaculum with dorso-caudal apophysis. Pseudosteineria sinica was discovered from the intertidal sediment in the Yellow Sea. It was characterized by unobservable amphideal fovea, different lengths of spicules, and gubernaculum with dorso-caudal apophysis. In this study, we provide detailed morphological features of three free-living marine nematodes by differential interference contrast microscopy.

During a survey of free-living marine nematodes of Korea, two new marine desmoscolecid nematodes belonging to subgenus Quadricoma Filipjev, 1922 were discovered. Tricoma (Q.) jejuensis sp. nov. and T. (Q.) unipapillata sp. nov. are described based on specimens obtained from washings of coarse sediments from eastern and southern coasts of Korea. Tricoma (Q.) jejuensis sp. nov. is characterized by having 33 quadricomoid body rings and inversion at main ring 23, pentagonal head with truncated anterior end, a pair of ocelli situated at main ring 6, somatic setae comprising of 8 pairs of subdorsal setae and 12 pairs of subventral setae, and relatively short spicules (42-46 μm long). Tricoma (Q.) unipapillata sp. nov. is characterized by 44 quadricomoid body rings and inversion at main ring 32, somatic setae comprising of 7 pairs of subdorsal setae and 10 pairs of subventral setae, globular head truncated anterior end, relatively short and stumpy cephalic setae with cuticular flange, one single naked ventral median genital papillae situated on main ring 20, and spicules with a proximally marked capitulum. Detailed morphological descriptions and illustrations of these two new species are provided in this study.

A new free-living marine nematode species of the genus Pseudosteineria Wieser, 1956 affiliated with the family Xyalidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Pseudosteineria varisetis sp. nov differed from its congeners by the combination of the following characteristics: a relatively long body (1,628-1,691 μm long in males), a circular amphideal fovea situated behind the subcephalic setae, the presence of lateral cuticular alae starting from behind the nerve ring, the presence of eight groups of long subcephalic setae, the presence of irregularly distributed variable lengths of somatic setae on the body, solid spicules (43.2-43.9 μm long) with a cephalated proximal end, a long tubular shaped gubernaculum with dorsal swelling, and a conico-cylindrical tail with two to four terminal setae. In this report, we provide a taxonomic description and illustrations of a new species of the genus Pseudosteineria by differential interference contrast microscopy.

Free-living nematodes feed on bacteria, algae, fungi, dead organisms, and living tissues. They release nutrients for plant use and improve soil structure and water holding capacity. They are usually the most abundant type of nematodes in soil and marine environments. This study has been conducted to survey the distribution and identification of soil nematodes from rhizosphere soil of plant for investigation of indigenous species according to Convention on Biological Diversity. Three species of free-living nematodes belonging to the order of Dorylaimida were found from paddy soil and soybean fields, Miryang, Gyeongsangnam-do and one species was found from soil, Dokdo island, Gyeongsangbuk-do, Korea. Aporcelaimellus obtusicaudatus, Eudorylaimus arcus and Mesodorylaimus spengelii are newly collected from Korea. A. obtusicaudatus can be recognized by its large body, short odontostyle being much thicker than cuticle at the same level, well developed gonads, shape and length of the tail. E. arcus is distinctive because of the wide lateral field, tail form and supplement arrangement. M. spengelii is smaller species with short odontostylet, simple guiding ring. Female tail more or less uniformly attenuated, tip is not swollen, nor curved dorsally.

A new free-living marine nematode species of the genus Belbolla Andrássy, 1973 belonging to the family Enchelidiidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Belbolla wonkimi sp. nov. differs from its congeners by the combination of the following characteristics: a relatively long body (3263-3396 μm), the absence of ocelli, nine oesophageal bulbs in the posterior pharynx, well-developed two winged precloacal supplements, longer spicule length (115-130 μm, 1.6-1.8 anal body diameter long), and a triangle-shaped shorter gubernacular apophysis (17-18 μm). Comparative tables on the biogeographical and morphological characteristics of Belbolla species are presented. A DIC (differential interference contrast) photomicrograph of the new species is also provided. This is the first taxonomic report on the genus Belbolla from Korean waters.

A new species of free-living marine nematode is described from intertidal sediments of the East Sea, Korea. Phanoderma koreense sp. nov. is characterized by the presence of well-developed pharyngeal and cephalic capsule, six inner labial sensilla present as minute papillae around with circular groove, long and slender spicules with 4-5 serrated distal end, located at the base of the precloacal supplement, a series of eight to nine stout and short setae on the ventral cloacal region and conico-cylindrical tail with two pairs of blunt setae. In this study, we provide taxonomic descriptions and illustrations of a new species by differential interference contrast microscope and a pictorial key to the valid species of Phanoderma Bastian, 1865. This is the first record of the genus Phanoderma in the East Sea, Korea.

Pine trees are ecologically important in Korea. They are seriously imperiled by Pine wilt disease (PWD), by pine wood nematode (PWN, Bursaphelenchus xylophilus). Here, we isolated and characterized bacterial endophytes (BEs) from pine trees in Korea for biological control of PWN using BE metabolites. Using culture-dependent approach BE isolates were extracted from three tissues (needles, stems, and roots) of four pine species across 18 sampling sites in Korea. Bacterial isolates were characterized into 389 distinct isolates based on 16S rDNA sequencing. Ethyl acetate crude extracts (CEs) of bacterial liquid cultures were prepared using ethyl acetate and screened for nematicidal activity against PWN. BEs (1,622 isolates) were isolated; their taxonomic binning resulted in 215 operational taxonomic units (OTUs). Analysis of species richness and Shannon’s diversity of the three tissues revealed that BEs colonized the needles more than the stem and root tissues. Furthermore, based on nematicidal activity screening of 389 isolates, 44 BEs were identified, with two isolates exhibiting a significant inhibitory activity against PWN. Taken together, these data revealed numerous nematicidal BEs in pine trees, providing new insights that can serve as an effective and promising alternative approach to combat PWD.

Oncholaimid nematode, Oncholaimus secundicollis Shimada, Kajihara and Mawatari, 2009, is firstly reported based on a comparative morphological study. The present specimens of O. secundicollis are collected from rocky intertidal seagrass on the eastern coast of Korea. Oncholaimus secundicollis is distinguished from all of its congeners by the following combination of morphological characteristics: buccal cavity large with thick cuticular wall and three teeth, left subventral tooth larger than right subventral or dorsal teeth, and the presence of two remarkable precloacal papillae with nine pairs of cloacal setae and single ventral tail papilla with two pairs of short setae. In this study, we provide taxonomic description and illustration of unrecorded species of the genus Oncholaimus.

Three unrecorded species of free-living marine nematodes, belonging to genus Enoplus Dujardin, 1845 collected from rocky intertidal seagrass on the eastern coast of Korea, are described and illustrated. Enoplus taipingensis Zhang and Zhou, 2012 is characterized by longer body size, a series of lateral setae throughout the tail in male, the presence of trumpet-shaped precloacal supplement with well-dilated proximal end, and the presence of spicules with five to eight semicircular plates. Enoplus meridionalis Steiner, 1921 is characterized by the presence of trumpetshaped precloacal supplement with slightly dilated proximal end, paired massive spicules, and tail with two pairs of stout terminal setae. Enoplus mammillatus Timm, 1959 is easily distinguished from the congeners by narrow tubular-shaped precloacal supplement. In this study, we provide detailed morphological features of three Enoplus species by differential interference contrast microscopy and scanning electron microscopy. This is the first report on the species of the genus Enoplus from the Korean waters.

선충절대기생세균(Pasteuria penetrans)이 감염되어 있는 온실토양을 이용하여 세균의 내생포자가 땅콩뿌리혹선충(Meloidogyne arenaria) 유충 표면에 부착하는데 대한 온도의 영향에 대해 시험하였다. 갓 부화된 뿌리혹선충 2령충(J2)을 페트리디쉬 내의 토양에 접종한 후 20℃, 25℃, 30℃, 35℃에서 7일간 처리하였다. 모든 온도에서 내생포자의 J2 부착률은 모두 100%로 나타났으나 J2당 내생포자 부착수는 25℃에서 28.3개로 가장 많았으며 30℃, 20℃ 및 35℃에서 각각 J2 당 20.2, 18.6 및 13.6개로 낮아졌다. J2를 접종하기 전에 세균이 있는 토양을 온도 별로 10일간 전처리하였을 때 내생포자 부착률은 실온에서의 60%에 비해 -30℃, 4℃, 40℃, 50℃ 및 100℃에서 각각 25.0, 31.7, 8.3, 5.0 및 0%로 현저하게 낮아졌다. J2 당 내생포자 부착수도 실온에서의 5.3개에 비해 -30℃, 4℃, 40℃, 50℃ 및 100℃에서 각각 3.5, 4.3, 1, 1, 0개로 적었다. P. penetrans 세균의 내생포자를 뿌리혹선충 종별로 J2에 부착 시험한 결과 땅콩뿌리혹선충에서는 100%였으나 당근뿌리혹선충(M. hapla)과 고구마뿌리혹선충(M. incognita)에서는 모두 0%로 본 균주는 뿌리혹선충 종에 대해 기주선호성을 가진 것으로 나타났다.

경북농업기술원 약용작물 전시포에서 약용작물 기생선충을 조사하던 중 Helicotylenchus clarkei Sher, 1966와 Rotylenchus usitatus Van den Berg et Heyns, 1974 등 2종이 우리나라 미기록종으로 확인되어 보고한다. 이로서 국내에는 총 8종의 Helicotylenchus와 총 9종의 Rotylenchus가 기록외었으며 각 종에 대한 분류검색표를 첨부하였다.

한국산 나선선충(Hoplolaimidae)을 조사하던 중 Helicotylenchus cavensessi Sher, 1966, Helicotylenchus paraplatyurus Siddiqi, 1972, Rotylenchus alius Van den Berg, 1986 그리고 Rotylenchus incultus Sher, 1965 등 4종이 우리나라 미기록종으로 확인되어 보고한다.

한국산 나선선충과(Hoplolaimidae)를 조사하던 중 Pararotylenchus blothrotylus Baidwin & Bell, 1981(둥근꼬리나선선충)(신칭), Rotylenchus feroxcis Eroshenko, 1981(주왕산나선선충)(신칭), Scutellonema conicephalum Sivakumar, 1982(알로에나선선충)(신칭) 등 3종이 우리나라 미기록종으로 확인되어 보고한다.

1985년부터 3개년에 걸쳐서 전국 387개 시.읍.면의 1, 160개 논에서 벼기생선충을 조사한 결과 우리나라 논에서 벼와 관련된 선충은 35종이 밝혀졌으며 본 조사로 26종이 새로이 추가되었고 세계적으로는 Criconemoides informis, Criconemella paragoodeyi, Criconema (Criconema) jaejuense, Ditylenchus longicauda, Eutylenchus africanus, Merlinius n. sp., Meiodorus n. sp., Ogma (Homogma) serrata, Ogma (Homogma) insulicum, Orientylus orientalis, Paratylenehus lepidus, Pararotylenchus Pini, Triνersus n. sp., Tylenchorhynchus claνicaudatus, Tylench-orhynchus nudus등 15종이 벼기생선충으로 새로이 기록되었다. 우리 나라에서 처음으로 발견된 Criconemella paragoodeyi, Ditylenchus longicauda 및 Merlinius n. sp. 등은 전국적으로 분포 하고 있을 뿐 아니라 밀도 또한 높으므로 벼의 중요한 기생선충으로 사료된다. 벼뿌리선충은 전국적으로 분포하며 밀도 또한 높았고, 애벼뿌리선충은 남부지방에서는 벼뿌리선충과 같이 분포되고 있으나 북부지방으로 갈수록 점차 밀도가 낮아지는 경향을 나타냈다

두 종류의 부리혹선충(M. incognita, M. hapla) 각각에 대한 우리나라 콩 장려품종들의 저항성을 검정한 결과 1. 인코그니타혹선충(M. incognita)에는 은대두, 백천, 동북대, 단엽콩이 저항성 이었으며 광두, 황금총, 부석은 중정도 저항성이었고 광교외 8품종은 감수성 이었다. 2. 당근혹선충(M. hapla)에는 장엽콩 한 품종만이 저항성이었으며 단엽콩, 힐, 동북태, 함안대립, 충북백은 중정도 저항성을 나타내었고 육우 3호 외 9품종은 감수성이었다. 3. 두 종류의 뿌리혹선충에 모두 저항성을 나타내는 품종은 없었으나 단엽콩과 둥북태는 인코니타혹선충(M. incognita)에는 저항성을 가지면서 당근혹선충(M. hapla)에는 중정도 저항성을 나타내는 좋은 품종이었다.