콩 재배지에서 콩씨스트선충(Heterodera glycines)과 반짝이씨스트선충(Heterodera sojae)의 지리적 분포에 관한 조사를 강원도와 충청북도 지역에서 수행하였다. 강원지역 10개시군, 67개 포장에서는 콩씨스트선충이 13개소, 반짝이콩씨스트선충이 5개소에서 검출되었고, 두 선충 혼 재하는 포장도 2곳이었다. 충북지역 9개 시군에서는 84개 조사 포장 중 27개소에서 콩씨스트선충이 검출되었고, 반짝이콩씨스트선충 4개소, 두 선충 혼재 발생지 5곳이었다. 강원, 충북 지역에서 콩씨스트선충류 검출 여부에 따라 발생하는 다른 식물기생성선충 속의 다양성과 우점도 지수 는 콩 재배지 사이에 유의한 차이를 나타내지 않았다. 콩씨스트선충과 토양 화학성 사이의 관계 분석에서는 결정계수가 낮게 나타났으며 콩씨스 트선충의 밀도가 높은 토양에서는 pH와 가용성 인산 함량이 높은 것으로 나타났다. 씨스트선충이 검출된 토양의 토성은 사질토가 전체 샘플의 60%를 차지하였다. 점토와 미사의 함량이 높은 토양에서는 콩씨스트선충의 밀도가 낮은 경향을 보였고, 모래 함량이 높은 토양에서 밀도는 높게 나타났다.

Soybean cyst nematode, Heterodera glycines is one of the major plant parasitic nematodes in soybean. Recently, another soybean cyst nematode, H. sojae was recorded from Korea. This study was conducted to determine the geographical distribution of the two soybean cyst nematodes in Gangwon-do and Chungcheongbuk-do, Korea. In Gangwon-do, H. glycines and H. sojae were detected in 12 and 5 of the 53 sites sampled, respectively, while in Chungcheongbuk-do, H. glycines was isolated from 14 of the 46 sites sampled. H. sojae was detected at only one site. Additionally, the two soybean cyst nematodes co-existed in 3 of the 46 sites.

We reported a new white soybean cyst nematode, Heterodera sojae in 2016. This species is closely related to H. glycineswhich has the same host plant. Morphological observations of the cyst, female, male and second-stage juveniles indicatedthat this species is differed from those of H. glycines. Cysts of H. sojae appeared more round, shining and darker thanthat of H. glycines. The distribution of this new cyst nematode in soybean field in Korea is unknown yet. In 2016, 270soil samples were collected from soybean fields and examined the existence of H. glycines and H. sojae. Total of 111samples (41.1%) contained cysts. Among them 77% were H. glycines and 23% were H. sojae. Our results suggest thatextensive researches are required for white soybean cyst nematode.

For management of soybean parasitic cyst nematodes, this study was conducted to investigate the resistance of the Korean soybean cultivars to HG type 2.5.7 of Heterodera sojae. Among the 44 Korean soybean cultivars, there was only one resistant cultivar ‘Namcheon’. ‘Sobaeknamul’, ‘Socheng No. 2’, ‘Pungsannamul’, ‘Cheongja’, ‘Miryang’ and ‘Daewon’ were moderately resistant to HG 2.5.7 of H. sojae populations. Eleven cultivars including ‘Paldal’ were moderately susceptible and the other cultivars were susceptible. Therefore, soybean cultivar ‘Namcheon’ should be cultivated in H. sojae infested fields, until varieties resistant against Heterodera species are more developed or identified. Moreover, ‘Namcheon’ is not recommended for cultivation because very weak to soybean mosaic virus, and it will be a candidate with resistant cultivar breeding resource.