There are relatively few cases of classical biological control in Korea. During 1904 to 1905 the wooly apple aphid, Eriosoma langigerum, had been happen to invade into Korea from Japan together with imported seedling of apple and its damage spread to Jinampo near Pyoung-Yang City and it occurred all across the country by 1934. In 1934 a parasitic wasp, Aphelinus mali, was introduced and released to apple orchards and found established in nature. And it was the first case of classical biological control in Korea. Afterward couple of classical biological control programs against invaded pests were conducted mainly by the RDA with variable results. For example the orange scale, Ceroplastes rubens, and the Eggar which were successfully controlled by introduction Anicetus beneficus and Thecodiplosis pinico, respectively.

신간척지에서 총체사료용 벼 주요 품종들의 담수직파 적응성을 평가하기 위하여 2012~2013년에 시험한 결과를 요약하면 다음과 같다.1. 입모율은 녹양과 수원552호 48%, 목우, 목양 및 수원544호 40~42%이었다. 2. 출수기는 녹양과 목양 8월 26~27일, 수원552호와 수원544호 9월 1~5일, 목우 9월 15일이었다. 3. m2당 수수는 278~333개였으며, 도복은 수원552호에서경미하게 발생하고, 그 외 공시품종에서는 발생하지 않았다.4. ha당 건물수량은 목우와 수원552호 15.8~16.8톤, 수원544호, 목양 및 녹양 이 13.1~14.3톤이었다.5. 조단백질 함량은 4.5~6.4%, ADF 함량은 27.1~30.1%,NDF 함량은 49.2~53.9%, TDN 함량은 65.1~67.4%이었다.6. 따라서 신간척지에서 총체사료용 벼의 담수직파재배에 가장 적합한 품종은 목우와 수원552호 이었다.

Lepidopterous pests can be a problem in corn cultivation in the southern region. This study investigated the occurrence of Ostrinia furnacalis, Helicoverpa armigera and Pseudaletia separata in corn field of southern region. O. furnacalis has investigated aspects occur in Iksan, Buan and Gochang. H. armigera and P. separata has investigated the aspects occur in Buan and Gochang. Occur from early May in sex pheromone trap, showing the highest density occurs in late May, the 1st occurrence of O. furnacalis adult was reduced since the beginning of June. the 2nd occurrence of O. furnacalis adult occurs in late August and showed the highest density occurred in early September. Occurrence time showed aspects similar to the three regions of the O. furnacalis adult. 1st adult occurs in early May from Buan, H. armigera showed the highest density occurs in early August and showed the highest density occurs in early July from Gochang. The 1st adult P. separata occurs in late April, showed the highest density occurs in late June from Gochang. However, the incidence density was lower in Buan.

Real Time PCR을 이용한 벼 흰잎마름병균의 밀도를 측정할 수 있는 새로운 방법을 개발하였다. Real Time PCR을 이용하여 벼 흰잎마름병을 예찰하기 위하여 TaqMan MGB probe를 이용한 프라이머인 Xan_PahgeF & Xan_PahgeR primer와 Xan_Pahge FAM MGB probe를 제작하였으며, 높은 특이성이 인정되었다. 병원균 배양액, 벼 흰잎마름병원균의 DNA, 병원세균에 오염된 물에서도 효과적으로 검출이 되었다. 농수로물이나 관개수에서 벼 흰잎마름병균의 밀도를 측정할 때 정량 PCR의 저해인자 제거 후 신속하게 벼 흰잎마름병균의 밀도를 측정할 수 있다.

벼 흰잎마름병균의 정확한 진단을 위하여 PCR용 진단 kit를 개발하였다. 본 PCR kit를 개발하기 위하여 벼 흰잎마름 병균 유전체 정보 중 phage-related integrase and transposase gene의 염기서열을 이용하여 프라이머를 각각 제작하였다. 프라이머 염기서열은 XOP-F (5-CGG TCT GCT CAA TGA GGA AGA-3)와 XOP-R2 (5-TGC AAT TGG TGT TCTCCA GG-3), XOT-F (5-GTC ATA GGT GAG GCT TCCC-3)와 XOT-R2 (5-AGT GCG ATC TTT CAG CAG G-3)로 벼 흰잎마름병균의 DNA를 401bp와 492bp를 증폭하게 제작하였다. PCR 증폭은 벼 흰잎마름병균만 증폭하였으며 다른 세균인 Escherichia coli, Agrobacterim, Pectobacterium caratovora subsp. cartovorum, P. atrosepticum, Pseudomonasputida, P. syringae, P. savastanoi pv. phaeolicola, P. savastanoipv. savastanoi and P. marginalis pv. Marginalis 등은증폭되지 않아 특이성이 인정 되었다. 본 프라이머로 병이 의심되는 벼잎과 논물에서 병원균을 3시간 이내에 검출할 수 있었다.

This study was carried out to know whether the host plant feeding have an influence to subsequent prey consumption of a zoophytophagous mirid, Nesidiocoris tenuis, with biological control potential. Piece of leave of Paprika, Sesame, and cotton ball soaked with water were respectively provided to the test insects, adult mirid starved about a day, and frozen eggs of Ephestia kuehniella, were presented to them for a day and counted the number of the eggs consumed by them. The mirid fed by Sesame leave took significantly less prey than both the Paprika and the water fed one.

Maize weevil (Sittophilus zeamais) and Indian meal moth (Plodia interpunctella) are the dominant species among the stored grain insect pests of the rice grain and bran. This experiment was conducted to investigate developmental characteristic and damages of S. zeamais and P. interpunctella on the rice. Under five constant temperatures, 15, 20, 25, 30 and 35℃, developmental periods from egg to adult of Sittophilus zeamais were 43.0, 36.4, 29.2, 20.8 and 16.3 days, respectively. With egg periods being 9.6, 7.3, 5.2, 3.2 and 2.6 days, and larval periods being 25.2, 22.6, 19.8, 14.5 and 11.3 days, and adult periods being 129.3, 116.1, 108.6, 89.2 and 73.3 days, respectively. Damages of S. zeamais adult at 15, 20, 25 and 30℃ were 67.2, 96.2, 134.0 and 174.5 for 24hr on the rice. Damages of P. interpunctella larval 15, 20, 25 and 30℃ were 56.2, 78.3, 109.4 and 138.7 for 24hr on the rice. The duration of maximum occurrence were June to August for S. zeamais, late May to early August for P. interpunctella.

The insecticidal effect for several commercially available environment friendly agricultural materials (EFAMs) is investigated to Cnaphalocrocis medinalis, Narana aenescens, Pseudaletia unipuncta and Parnara guttata on rice. In the insecticidal effects for 2-3rd instar larvae of lepidopteran after treatment with 19 EFAMs, more than 95% of mortality rate showed 5 EFAMs in C. medinalis, 12 EFAMs in N. aenescens, 9 EFAMs in P. unipuncta, and 14 EFAMs in P. guttata, respectively. Among 4 EFAMs selected for C. medinalis in indoor, more than 70% in control effect is seen EFAM-B(85.2%), EFAM-I(79.1%) and EFAM-M (78.3%), respectively, in rice field. The insecticidal effect for EFAMs is investigated to Nilaparvata lugens, Laodelphax striatellus and Nephotettix cincticeps on rice. In the insecticidal effects for 2-3rd nymph and adult after treatment with 19 EFAMs, more than 95% of mortality rate showed 5 EFAMs in N. lugens adult, 7 EFAMs in N. lugens nymph, 6 EFAMs in L. striatellus, and 5 EFAMs in N. cincticeps, respectively. Insecticidal effect for N. lugens was sustained until 10 day in rice treated with 7 EFAMs selected in indoor. Among them, EFAM-L, EFAM-P and EFAM-R was sustained in low density until 27 day. But EFAM-D, EFAM-L, EFAM-N and EFAM-S showed high density until 27 day and additional control was needed.

Biological control of rice insect pest is an important component of an IPM program. There are many species of natural enemies which contribute to the suppression of rice pest populations below economic injury levels. In order to use biological control more efficiently, it is a need to identify beneficial species and determine their roles in possible regulation of insect pests. There is a rich complex of biological control agents in rice and bund. This research was carried out to investigate the population density of insect pests and natural enemies in the rice field and bund. A total of 7 pest species and 15 natural enemy species were collected in the rice field. 10 pest species and 20 natural enemy species were collected in the bund, also. Changes in population density of insect pests and its prey were investigated in the rice field and bund. Population densities of insect pests were low at any time during the rice growth period in the field. This could be the high density of natural enemies. Bunds served as refuge for natural enemies when rice maturity. There are rich complex of biological control agents in rice field and bund. So, when we practice integrated pest management(IPM) of rice insect pests, we should use various natural enemies.

We have gathered rice grain and bran from conventional mills and RPC(Rice Processing Complex) for the survey of stored grain insect pests. Maize weevil(Sittophilus zeamais) is the dominant species among the stored grain insect pests of the rice grain and bran. Under three constant temperatures, 15, 20 and 25℃, developmental periods from egg to adult were 43.0, 37.5 and 29.2 days, respectively. With egg periods being 9.6, 7.3 and 5.2days, and larval periods being 25.2, 21.8 and 19.8days, and adult periods being 126.1, 110.3 and 108.6days, respectively. The adults of Maize weevil feed basically on the same the foods as the larvae but not as restricted in their diets because the larvae need to develop inside whole grains. Feeding of S. zeamais adult usually began 3∼4 days after emergence at 25℃. Then adult feeding ca. one rice a day, reaching a peak of 20∼40days after emergence.

The occurrence and damage of stink bugs were monitored at South Korea from 2007 to 2008. A total of 11 stink bug species were observed in paddy field and occurrence periods of stink bugs were significantly differed by species. In occurrence period and damage of stink bug feeding in paddy field, Scotinophara lurida occurred from June, Cletus punctiger, Eysarcoris aeneus, Rhopalus maculatus, Riptortus clavatus, E. ventralis, Stenotus rubrovittatus occurred from August and Pachygrontha antennata, C. schmidti, Trigonotylus caelestialium, Paromius exiguus occurred from September. When we were classified into two region with mountain and plain area cultivated rice, generally C. puntiger population was higher in mountain area than plain area, and E. aeneus was higher in plain area than mountain area. Also, stink bug species were higher in environment condition formed with a paddy field and a waterway overgrown with weeds. Control threshold for E. aeneus in paddy field was 1-2 individuals/heading stage, and then rate of pecky rice made to 5.0% while milk stage, dough stage and yellow ripe stage made to less than 5.0%.

The green rice leafhopper, Nephotettix cincticeps is an insect vector which transmits virus diseases of rice plant causing severe damage to the rice and its damage both quality and yield of rice. Survival rate of overwintering N. cincticeps in Alopeculus acquadis among 15 species of the winter crops and weeds was 37.8% and its most preferred. Density of N. cincticeps in environment-friendly agriculture area which cultivated Astragalus sinicus as a green manure crop in winter season increased in number wintering pass in Alopeculus acquadis and Astragalus sinicus as host plants, because of control of N. cincticeps was not enough in the previous year. Survival rate of N. cincticeps was higher mainly in habitation mixed with rice straw, Astragalus sinicus and Alopeculus acquadis as winter habitation. It warmed due to the effect of the keeping warmth inside of a rice paddy field and the bank around a rice field covered with rice straw or Astragalus sinicus. Also, habitation conditions were optimal for survival because of growing Alopeculus acquadis as the major host plant of N. cincticeps in that place.

Four bacterial blight resistance genes, Xa1+Xa3+xa5+Xa21, pyramid elite japonica rice lines were developed for enhancing the resistance of rice against Xanthomonas oryzae pv. oryzae in Korea. Seven doubled haploid (RDL1-7) and ten F6 lines (RPL1-10) having Xa1+Xa3+xa5+Xa21 which were derived from the cross between Ilmi, high grain quality japonica rice cultivar carrying Xa1, and Iksan575, elite line carrying Xa3+xa5+Xa21, were developed using marker-assisted selection for resistance genes and phenotypic selection for bacterial blight resistance and agronomic traits. Among resistance genes combinations in F2 population, four resistance genes combination, Xa1+Xa3+xa5+Xa21, showed the highest resistance and conferred the enhanced resistance than three genes combination, Xa3+xa5+Xa21. Four genes pyramid lines (RDL and RPL) showed broad-spectrum resistant against 16 Korean bacterial blight isolates and the yield and quality of the lines did not alter by the inoculation of K3a, the most virulent race in Korea. In addition, these lines had excellent plant type and exhibited more enhanced yield than previously developed resistant cultivars. Four bacterial blight resistance genes combination, Xa1+Xa3+xa5+Xa21, was efficient and promising combination and developed lines with four genes could be useful materials and will be applied to the breeding programs for enhancing the resistance of japonica rice against bacterial blight.

연구는 간척지에서 사료용벼를 재배하여 조사료를 생 산함으로써 간척지 이용률 증진과 조사료생산의 두가지 가 능성을 검토해보고자 일반답과 간척답에서 사료용벼를 재 배하여 생육특성, 총체수량 및 사료가치 등을 조사하였다. 1. 출수기는 일반답에서 8월15일에서 8월30일, 간척답에 서 8월14일에서 8월 29일이었으며, 간척답이 일반답 보다 1~2일 빨랐으며, 목우는 일반답에서 8월 26일, 간 척답에서 8월 27일로 수원 544호를 제외하고는 가장 늦었다. 2. 초장은 일반답에서 105~135 cm범위이었고, 간척답에 서 97~126 cm범위였으며 일반답에서는 목양이 간척 답에서는 수원544호가 가장 컸다. 주당경수는 일반답 과 간척답 모두 녹양이 16개로 가장 많았고 총체수량 은 일반답은 15.26~23.24 MT ha-1, 간척답은 11.94~18.89 MT ha-1범위이었으며 목우벼가 두지역에서 가장 많이 생산되었다. 각품종별 수량은 일반답에 비하여 78~84% 수준이었다. 3. 단백질 함량은 일반답에서는 녹양벼가 높았으나 간척 답에서는 6.7~8.7%로서 상대적으로 낮은 수치를 보였 고 목양벼가 8.7%로 가장 높았다. 각 품종별 NDF는 31.2~55.5% 수준을 나타냈으며 ADF는 일반답에 비 하여 큰 차이를 보이지 않았으며 가소화 양분총량을 계산해본 결과 일반답에서 목우벼가 71.2%로 가장 높 았고 전체적으로 60%이상의 함량을 보여 간척지에서 재배하여도 사료로서의 가치는 충분할 것으로 생각되 었다. 4. TDN수량을 비교해본 결과 일반답에서 TDN수량은 목우벼가 16.54 MT ha-1로 가장 높았으며 간척답에서 도 12.69 MT ha-1 로 가장 높은 수량을 보였다. 5. 이상의 결과로 간척지에서 사료용벼를 재배할 경우 일 반답에 비하여 80%정도의 수량을 보여 간척지에서 재 배가능성을 확인하였으며 목우를 재배할 경우 수량 및 사료가치면에서 가장 좋을 것으로 생각된다.

본 연구는 벼멸구, 벼흰잎마름병, 벼줄무늬잎마름병에 저항성인 자포니카 복합내병충성 품종을 조기에 확보하고자 약배양을 수행하여 목표 저항성 유전자 조합의 우량 고정계통을 개발하고 육성 과정 중에 발생할 수 있는 문제점을 파악하여 병해충 저항성 육종사업에 반영하고자 수행하였다. 벼흰잎마름병과 벼줄무늬잎마름병에 저항성인 우량 계통 HR26234- 12-1-1과 벼멸구, 벼흰잎마름병, 벼줄무늬잎마름병에 저항성인 SR30071-3-7-23-6-2-1-1을 인공 교배한 F1을 약배양하여 213개 고정계통을 육성하였다. HR26234는 Xa3+xa5, Stvb-i, SR30071은 Bph18, Xa4, Stvb-i를 가지고 있는 것으로 확인되었다. 이들 유래 약배양 계통들은 모두 Stvb-i를 가지고 있었고, Bph18+Xa3, Bph18+Xa4, Bph18+Xa3+xa5, Bph18+Xa4+xa5, bph18+Xa3, bph18+Xa4, bph18+Xa3+ xa5과 bph18+Xa4+xa5의 조합이 확인되었다. 약배양 집단에서 xa5+Bph18(또는 bph18)+Stvb-i 조합이 발생하지 않았고 Bph18 보유 계통이 bph18 보다 적게 발생하는 등 segregation distortion이 발생하였다. Bhp18을 보유하며 벼멸구에 저항성인 계통들이 감수성인 계통들에 비해 간장이 컸다. 선발된 Bph18+Xa4+xa5+Stvb-i 조합의 계통은 단간이면서 벼멸구, 벼흰잎마름병, 벼줄무늬잎마름병에 저항성을 나타내었으나, 낮은 수량성과 일부 불임의 발생, 단간임에도 도복에 안정적이지 못한 특성을 나타냈다. 병해충에 대한 저항성 육종사업에서 약배양을 활용하여 조기에 육종 목표를 달성하고자 할 경우에 segregation distortion이 발생하여 편의 된 변이가 발생할 수 있고, 저항성 유전자 도입 시 linkage drag에 의해 예기치 못한 열악형질 특성이 나타날 수 있음을 고려하여 신중하게 목표에 접근하여야 할 것으로 생각한다.

본 연구는 우리나라 벼흰잎마름병 균주에 대한 인디카형과 자포니카형의 단일 저항성 유전자의 반응과 이들의 집적 효과를 비교 분석하고 자포니카형의 유망 조합을 제시하여 향후 우리나라 환경 여건에 효과적인 저항성 품종을 육성하고자 수행하였다. 단일 저항성 유전자 계통중 Xa1, Xa3, Xa21은 생태형 간에 차이가 없었으나 Xa4와 xa5는 자포니카에 비해 인디카형에서 저항성이 강하였다. 인디카형과 자포니카형에서 모두 저항성 유전자가 집적되었을 경우에 단일 또는 두 개의 저항성 유전자에 비해 저항성이 정도가 증가하거나, 저항성 수준이 높은 유전자가 저항성 수준이 낮거나 균계 특이적 이병성을 나타내는 저항성 유전자를 보완하는 효과를 나타냈다. 자포니카형에서 새롭게 확인된 저항성 유전자 집적 조합인 Xa3+Xa21, xa5+Xa21과 Xa3+xa5+Xa21은 우리나라 우점 균주와 16개 균주에 대해서 저항성이었으며 현재 우리나라 벼흰잎마름병 저항성 육종에서 주력 저항성 조합으로 이용되고 있는 Xa3+xa5 보다 높은 수준의 저항성을 나타냈다. 이들 저항성 유전자 집적 조합은 균계 분화 등에 따른 저항성 붕괴에 안정적으로 대응할 수 있고 저항성을 효과적으로 강화할 수 있는 유망 조합으로 생각되어 자포니카 벼흰잎마름병 저항성 증진을 위한 목표 조합으로 설정하여 육종사업을 수행하겠다. 

Japonica rice cultivars exhibit high susceptibility to bacterial blight(BB) disease due to genetic vulnerability in Korea. Korean japonica resistant rice cultivars mainly possess one of the genes, Xa1 or Xa3 for BB resistance. These resistance genes are becoming susceptible to K3a, resulting in serious rice yield reduction. This study was carried out to confirm the effect of xa13 gene pyramiding for developing of japonica rice cultivars resistant to BB pathogen breaking down Xa1 or Xa3. IRBB4 conferring Xa4 gene was resistant to K1(HB01013), K2(HB01014), K3(HB01015), and moderately resistant to K3a(HB01009). IRBB5 having xa5 gene was resistant to K1, K2, K3, and K3a. The recessive gene xa13 was resistant to K1 race but susceptible to K2, K3, and K3a. But Xa21 gene is susceptible to predominant K1 race but resistant to other races such as K2, K3, and K3a. Two genes Xa3 and xa13 were susceptible and Xa4 gene was moderate resistant to 24 isolates. xa5 and Xa21 genes were resistant to all isolates including K3a. When xa13 gene combined Xa4, xa5 and Xa21 genes, effect of xa13 gene pyramiding showed higher resistant reaction than that having singe gene out of Xa4, xa5, and Xa21. The order of resistance against 24 isolates breaking down Xa3 gene was IRBB55(xa13+Xa21) > IRBB53 (xa5+xa13) > IRBB51 (Xa4+xa13).

Japonica rice cultivars exhibit high susceptibility to BB disease due to genetic vulnerability in Korea. Korean Japonica rice cultivars mainly posses the genes, Xa1 and Xa3 for BB resistance. These resistance genes are becoming susceptible to K3a, new races of BB, resulting in the breakdown of resistance in high yielding Japonica cultivars. It is imperative to look for novel R-genes for improvement of japonica rice resistant to BB races. This study was carried out to conform useful single gene resistant to 24 BB isolates (including K3a, HB01009) breaking down Xa3 gene. Cultivars and near-isogenic lines (NILs) carrying Xa1, Xa2, xa8, Xa10, Xa11, xa13 genes were susceptible to 24 isolates, whereas IRBB4 carrying Xa4 gene was moderate resistance. IRBB5 and IRBB21 having xa5 and Xa21 genes, respectively, expressed resistance to these isolates. IRBB7 having Xa7 gene showed resistance response to 24 BB isolates, whereas JBB-107 carrying Xa7 gene was susceptible to 10 BB isolates and moderate resistant to 14 BB isolates. Xa7 gene showed different resistance response according to genetic background of used recurrent parent. With these findings, Xa4, xa5, and Xa21 would be the most prospective genes to 24 isolates used in screening.

It was practiced that crop rotation between barley and soybean to reduce the Barley yellow mosaic virus(BaYMV) in barley and investigated barley growth and yield. The diseased degree of barley by BaYMV reduced in one or two years fallow of barley with the soybean cultivated continuously in summer season. In the same practices, barley growth such as plant height and tiller number was better than another crop rotation plots. In yield components of barley, culm length and number of head was different among the treat plots. One or two years fallow of barley plots was better results than others. The yield of barley also showed significant difference in above one or two year fallow of barley. These plots showed higher yield from 24% to 32% than continuously cultivated barley and soybean plot. In comparison to conventional practice barley and rice, these rotation system presented higher barley yield from 3% to 13%. These crop rotations affect the density of the BaYMV vector, Polymyxa graminis. In these results, crop rotation with one or two years fallow of barley in viral infested paddy fields could reduce the BaYMV disease incidence and fungal vector density in soil.