초록 ▼

Ⅳ. 연구개발 결과
[제1세부과제] 콩에 가해하는 노린재류 해충의 알기생천적 조사
노린재류의 알기생천적을 탐색하고자 한국응용곤충학회지에 1962년부터 2013년까지 50년에 걸쳐 게재된 논문 총 1,851편을 15개 주제로 분석하여 그 중 천적 분야에 해당하는 123편의 논문을 검색하였다. 천적 분류군을 중심으로 볼 때, 벌목, 선충, 병원균, 포식성 응애의 순으로 많았으며, 기주별로는 노린재목, 나비목, 파리목의 순으로 많이 게재되었다. 본 연구에서 관심 있는 콩에 발생하는 노린재류의 천적에 관한 논문은 2000년대 들

Ⅳ. 연구개발 결과
[제1세부과제] 콩에 가해하는 노린재류 해충의 알기생천적 조사
노린재류의 알기생천적을 탐색하고자 한국응용곤충학회지에 1962년부터 2013년까지 50년에 걸쳐 게재된 논문 총 1,851편을 15개 주제로 분석하여 그 중 천적 분야에 해당하는 123편의 논문을 검색하였다. 천적 분류군을 중심으로 볼 때, 벌목, 선충, 병원균, 포식성 응애의 순으로 많았으며, 기주별로는 노린재목, 나비목, 파리목의 순으로 많이 게재되었다. 본 연구에서 관심 있는 콩에 발생하는 노린재류의 천적에 관한 논문은 2000년대 들어서 게재된 단 3편에 불과하였다. 이에 따라 콩에 가해하는 주요 노린재 3종 중 톱다리개미허리노린재의 천적 4종, 풀색노린재 천적 4종, 알락수염노린재 천적 3종의 문헌 기록을 조사하였다.
실제 야외에서 발생하는 천적으로 조사하고자 경기도 수원에 황색수반을 설치하여 채집된 곤충을 분석한 결과, 9월보다 8월에 트랩당 채집된 벌목 곤충도 많았고 과도 다양하게 나타남을 알 수 있었다. 콩 재배에 가장 문제되는 톱다리개미허리노린재의 알을 채집하여 기생 여부를 조사한 결과, 납작먹좀벌과의 Gryon japonicum (Ashmead)과 깡충좀벌과의 Ooencyrtus nezarae Ishii의 두 종이 섞여 있었으며, 성비는 G. japonicum이 37.5, O. nezarae가 25.0으로 조사되었다.
신규 조성포장에서 천적의 동태를 살펴보기 위해 알을 채집하여 조사한 결과, 첫 해부터 알기생봉의 기생률이 평균 46.2%로 조사되었으며, 일반농가에서도 톱다리개미허리노린재 알기 생봉의 기생률이 60%를 넘게 나타나 알기생봉에 의한 톱다리개미허리노린재의 밀도 억제가 활발한 것으로 조사되었다.
살충제 처리 시 천적이 받는 영향을 알아보고자 합성농약과 친환경 제제를 살포하고 조사한 결과, 약제의 영향은 미미한 것으로 나타났지만, 기생봉 3개 주요 상과의 경우 납작먹좀벌상과의 상대적인 구성비가 크게 감소하여 가장 많은 영향을 받는 것으로 추정되었다.

[제2세부과제] 콩 들불병 발생생태 구명 및 관리 적용기술 개발
2013-2015년에 들불병 전국 발병 조사 결과, 들불병 발생포장률은 ‘13: 5.3%, ‘14: 13.2%,’15: 3.8%로 나타났으며, 주로 재래종(서리태, 서목태 등), 태광, 대원, 풍원나물콩, 풍원콩 등에 발병하는 것으로 조사되었다. 여기에서 수집된 isolates들의 유전자를 분석하고 레이스를 검정한 결과, 16s-23s ribosomal RNA intergenic spacer 약 530bp 염기서열 중 136bp-187bp 구간에서 일부 pathovar가 다른 종들과 차이를 보였으며, 수집된 균들은 모두 Tabtoxin을 가지고 있는 레이스 0으로 확인되었다.
들불병에 대해 포장검정을 실시한 결과, 다원, 태광, 대원, 청자, 황금콩은 들불병에 감수성 반응을 보였으며, 대풍, 신팔달2호, 연풍, 청아, 풍산나물콩 등은 저항성 반응을 보였다. 감수성 품종인 태광콩에서 들불병으로 인한 수량 감소는 13%에 달했다. 콩 들불병에 serenade (Bacillus subtilis QST713) 처리시 실내검정과 온실검정 모두에서 효과적으로 조사되었다.

[제1협동과제] 콩 노린재의 유인트랩을 이용한 방제 기술 개발
톱다리개미허리노린재의 집합페로몬트랩 설치 후에도 포장 내 노린재 밀도는 감소하지 않으며, 트랩 내 포획된 수도 매우 적었다. 9월 이후에는 집합페로몬트랩 설치가 오히려 포장내 노린재 밀도를 증가시키는 걸로 조사되었다. 휴면유기된 노린재가 페로몬에 대한 반응률이 증가하고 교미와 산란을 하지 않는 것으로 보아 재배 후반부 노린재 유인력 증가는 생식휴면에 들어간 노린재의 먹이자원 탐색과 관련이 있는 것으로 생각된다.
트랩을 콩재배지의 가장자리(1 m 미만)에 설치하는 것에 비해 가장자리로부터 거리를 떨어뜨려 설치할 경우 포장 내 노린재 밀도가 최대 80% 감소하였다. 하지만 트랩 설치 전보다 밀도가 낮아지지 않았다. 친환경방제재로서 보타니가드(Botanigard, Beauveria bassiana GHA)의 야외 실증에서 처리 농도와 횟수를 달리한 처리 간에 유의한 차이는 없었지만, 유의한 밀도감소효과가 약충에서 있었다.

[제2협동과제] 콩 세균병의 약제 방제체계 확립
방제약제가 등록되지 않은 콩들불병과 세균점무늬병에 대한 약제 등록을 위해 각 병해별로 옥시테트라사이클린수화제, 스트렙토마이신수화제, 발리다마이신입상수화제, 옥솔린산수화제의 4종을 시험한 결과, 잎이 황화되고 찢어지는 약해가 발생한 스트렙토마이신수화제 이외의 3종 약제는 효과가 우수하고 약해가 없어 방제약제로 등록하였다.
들불병 방제적기를 구명하기 위해 약제를 살포하였을 때 개화기 및 개화 후 10일 경에 약제효과가 가장 높았으나 약제 처리 시간과 비용을 절감하기 위해 불마름병과 방제시기를 동일하게 적용하여 개화 후 10일 경에 적용약제를 1회 살포하는 것이 전체적인 병해관리에 가장 효과적인 것으로 조사되었다.
불마름병은 주로 엽맥을 따라 병징이 나타나며 엽육 부위에는 상대적으로 발병이 적은 이유를 알아보고자 전자현미경 및 접종에 의한 미생물 프린팅을 실시하였을 때, 엽육 부위는 미세한 엽모가 발달되어 있었으나 엽맥 부위에서는 엽모가 관찰되지 않았으며 세균 접종 후 전자현미경 관찰 시에도 엽모가 없는 부위에 세균이 부착되고 프린팅시 엽맥 부위에서만 세균의 배양이 관찰되어 엽모가 물리적 저항성 요인으로 작용하여 엽육부분은 감염이 상대적으로 낮아지는 것으로 구명되었다.

Abstract ▼

[제1세부과제] 콩에 가해하는 노린재류 해충의 알기생천적 조사
Hemipteran pests, especially bean bug, Riptortus pedestris (Fabricius) (Hemiptera: Alydidae), becomes one of the most harmful insects in korean soybean cultivation. The demand for the stable production of safe soybean has been growing as the public concern about

[제1세부과제] 콩에 가해하는 노린재류 해충의 알기생천적 조사
Hemipteran pests, especially bean bug, Riptortus pedestris (Fabricius) (Hemiptera: Alydidae), becomes one of the most harmful insects in korean soybean cultivation. The demand for the stable production of safe soybean has been growing as the public concern about the soybean became larger by the nutritional value of soybean was investigated. The interest for Biological control, therefore, is growing to accomplish the goal of stable production of soybean. Egg parasitoid is essential agent for carrying out biological control.
The 1,851 papers issued in ‘Korean journal of applied Entomology’ for 50 years from 1962 were arranged according to its title by 15 themes and investigated. A total of 123 papers were classified in ‘natural enemy’ field. Its first paper was issued in 1971, and researches were activated in 1980s. The agents were mainly Hymenoptera (49 papers, 38.0%), Nematoda (14.0%), entomopathogenic organisms including fungi (10.1%), predatory mites (8.5%), and so on. The major hosts were Hemiptera (25.5%), Lepidoptera (18.2%), Diptera (12.7%), etc. However, the papers which dealt hemipteran pests on soybean were only three, which suggested the necessity of strengthening the research on this field. The parasitic natural enemies of three major hemipteran pests (Riptortus pedestris, Nezara antennata, Dolycoris baccarum) were surveyed in the literatures, and four, four, three species were arranged, respectively. In addition, 2,291 cases of host-natural enemy interation were arranged in datasheet.
Minute hymenopteran insects were collected by yellow pan trap in Suwon in 2013, and classified by family-level. The number of collected per trap and the number of the families were larger in September than that in August.
The parasitic rate of the eggs of bean bug collected in Suwon in 2013 was 66.7%. It was due to the parasitism of Gryon japonicum (Ashmead) (Platygastridae) and Ooencyrtus nezarae Ishii (Encyrtidae), and sex ratio were 37.5 and 25.0, respectively. The result of the regional survey in 2014 showed that average parasitic rate of the eggs of bean bug was 48.5%, and the differences among the region were big, due to the small number of eggs. The parasitic rate of the eggs of bean bug was 66.7%, using the method like mark & recapture.
The parasitic rate of the bean bug eggs was investigated in the newly established soybean filed in Jeonju in 2015. The rate of emergence and of parasitism were decreased and the rate of ‘no response’ was increased as the time passed to autumn. The average rate of parasitism was 46.2%, and the maximum was 83.3%. The average rate of emergence was only 7.1%, and the maximum was 43.8%. The average rate of ‘no response’ was 46.7%.
The parasitic rate of the bean bug eggs was more than 60% in ordinary farmers’ field, and it suggested the possibility of adoption for successful biological control. The composition of Gryon japonicum (Ashmead) and Ooencyrtus nezarae Ishii was differed by the region. The influence of the spray of insecticide was investigated. Two kinds of insecticides, bifenthrin and ‘nim extract+plant extract’, didn’t show the meaningful differences, and Platygastroidea was influenced bigger than Chalcidoidea and Ichneumonoidea.

[제2세부과제] 콩 들불병 발생생태 구명 및 관리 적용기술 개발
Wildfire, caused by Pseudomonas amygdali pv. tabaci is one of the most destructive bacterial diseases and was recognized as a disease of soybean in 1943. Wildfire has been seen a steady increase in the incidence and prevalence on some cultivars of soybean in Korea by climatic changes, but there is little information about neither effective control measures for wildfire nor soybean varieties showing complete resistance to the disease. The nationwide survey of the occurrence of soybean wildfire showed that 5 out of 18 regions in 2013, 19 out of 30 regions in 2014 and 9 out of 28 regions in 2015 had been infected with Pseudomonas amygdali pv. tabaci . The severity of disease had been varied depends on the cultivar, cultivation regions and climates, however, cultivar ‘seoritae’ was susceptible for 2013 to 2015. The disease severity of 2014 was twice of that of 2015. Since the temperature of 2014 and 2015 were very similar, but the precipitation in 2014 was more than twice of that of 2015, the precipitation of 2014 had a great impact on the wildfire disease severity.
In this study, the efficient and reliable screening method to evaluate soybean genotype for resistance to P. amygdali pv. tabaci in field had been developed. In order to determine the host resistance of the soybean cultivar against P. amygdali pv. tabaci , development of symptom by infiltration inoculation was evaluated. Significant differences between susceptible plants and resistant plants were observed through these assays. Based on these results, ‘Shinpaldal2’ and ‘Daepung’ are resistant to wildfire compared to ‘Hwangeum’ and ‘Taekwang’. The optimum temperature of this pathogen was between 20 - 25℃ and when the pathogen was in the optimum temperature, the responses of susceptible or resistant cultivar were dramatically different.
Resistant lines identified through this assay could be directly used in soybean breeding programs for wildfire resistance. Prior to initiation of resistance breeding of soybean wildfire, it is imperative to set uniform resistance screening techniques. The obtained results can be effectively used to enhance the selection of wildfire resistance as well as directly applied in resistant soybean development.

[제1협동과제] 콩 노린재의 유인트랩을 이용한 방제 기술 개발
Efficacy of aggregation pheromone trap of Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) was evaluated in experimental soybean fields by using both before/after and with/without design. We also evaluated the aggregation pheromone trap in commercial soybean fields. In 12 commercial fields, three treatments (trap installation for the entire cultivation period, trap installation until September, and no trap installation) were tested. In both before/after and with/without experiments, the numbers of R. pedestris were not significantly affected by the trap installation until mid August. But, surprisingly, the pest’s abundance increased significantly in the month of September and October. In commercial fields, trap installation did not reduce bug population, and adult population in fields was also in increasing trend in the fall.
Placement of traps in fields increased pod and seed damage by 2.7 and 2.2 times, respectively, compared to the control in experimental fields, while no such reduction was observed in commercial fields. Riptortus pedestris female in reproductive diapause showed higher response to the aggregation pheromone in both field and laboratory population. Most R. pedestris in reproductive diapause did not mate or reproduce. Thus, more attraction to aggregation pheromone during the fall period may be due to the exploitation of food sources.
As the trap placement in soybean fields does not reduce the pest population and crop damage, we evaluated the repellency of alarm pheromone by installing them in the center of field with aggregation pheromone trap installed in different distance from field perimeter (push-pull experiment). When installed at > 5 m from the field, aggregation pheromone trap can reduce bug population. But, alarm pheromone used as push strategy did not cause additional reduction in the field population despite the inhibitory effect on the attraction to the aggregation pheromone trap.
A mycoinsecticide, Beauveria bassiana (strain GHA) marketed as BotaniGard®ES, was evaluated as a biocontrol agent against R. pedestris. In laboratory bioassay, no difference in susceptibility was found between laboratory reared and field collected population. In field application trial, nymph population was reduced regardless of dose and frequency of spray. But, adult and egg populations were not affected by the application of B. bassiana.

[제2협동과제] 콩 세균병의 약제 방제체계 확립
Four bacterial pathogens of soybean, Pseudomonas savastanoi pv. glycinea, Pseudomonas syringae pv. syringae, Xanthomonas campestris pv. glycines, Pseudomonas syringae pv. tabaci, were reported and they are major pathogens in Korea. They induce blight or spot in leaves, causing yield loss. Therefore, control of bacterial diseases is very important factor for stable soybean production. But there is no information about proper application time and effective antibiotics because bacterial diseases in soybean was ignored to reduce managing cost. Recently, with concern on health, soybean consume is increasing as well as the price of soybean. This social phenomenon requires development of bacterial diseases control method for yield increase. This experiment was carried out to select proper antibiotics for control of bacterial disease of soybean and know the most effective application time of them. In 2013, four antibiotics were tested to evaluate control efficacy on bacterial disease of soybean. Experiment was carried out at two provinces, Daegu and Bonghwa, and cultivar was ‘Taekwang’. Tested antibiotics were Oxolinic acid WP, Oxy-tetracyclin WP, Streptomycin WP, Validamycin WP. Each antibiotics was applied 3 times at 10 days interval from early Aug. Incidence of bacterial disease in 2013 was too low to evaluate control efficacy resulting in failure of evaluation. But chemical injury in double dose application was appeared at treatment of streptomycin WP. So, same treatments except streptomycin were repeated at same place in 2014 and three antibiotics were successively controlled bacterial diseases. This results were submitted for reference of agricultural chemical registration to be officially used in field. To know the most effective application time to control of fire blight, oxolinic acid was selected and sprayed one time at blooming time, 10, 15, 20, 25, 30 days after flowering. The control efficacy was highest in spraying at 10 days after flowering. Bacterial pustule of soybean is caused by Xanthomonas axonopodis pv. glycines, one of the most important diseases in soybean. The symptom of bacterial pustule is mainly distributed around leaf veins. However, the reason has not been known. Soybean leaves were collected and was observed using scanning electron microscopy(SEM) and light microscopy. Though many hairs were observed at abaxial sides of the leaf, few hairs were observed at tissue around the leaf veins. In addition, unidentified bacterial cells and dusts at the no hair part near veins were observed. In the inoculation assays, the cells of X. axonopodis pv. glycines were observed near leaf veins. The imprint of underside of soybean leaves inoculated with X. axonopodis pv. glycines on PDA showed that the growth of bacteria around veins was observed but no bacterial growth at the part with leaf hairs. Our data demonstrated that soybean leaf hairs play an important role as a physical barrier for structural resistance of soybean against bacterial pustule.