Metarhizium은 대표적인 곤충병원성 진균 중 하나로, 종에 따라 매우 다양한 곤충에게 병원성을 일으키는 폭 넓은 기주범위를 형성한다. 이들이 주로 생성하는 것으로 알려진 destruxins (DTXs)이라는 2차 대사산물은 살충 활성 뿐만 아니라 항바이러스, 항증식, 항암 등 다양한 분야에서 효능이 연구되고 있어, 해당 물질에 대한 관심이 집중되고 있다. 살충 물질로서의 DTXs는 여러 곤충에 있어 병원성을 나타내는 것이 확인되었으나, 해충 으로서 전 세계적으로 심각한 경제적 피해를 일으킴과 동시에, 화학 살충제 저항성 문제가 야기되고 있는 목화진 딧물에 대해서는 아직 DTXs의 역할이 연구되지 않고 있는 실정이다. 본 연구에서는 목화진딧물에 대해 곤충병원 성 진균 Metarhizium spp.의 병원성 발현에 DTXs가 미치는 역할을 간접적으로 확인하기 위해, qPCR을 활용하여 진균 처리 후 목화진딧물 사망 시간과 관련하여 충체 내 DTX 합성효소의 발현을 비교 분석하였다.

Mycoviruses are a group of viruses that infect filamentous fungi. While most hosts infected with mycoviruses do not show any symptoms. In some cases, mycoviruses induce various phenotypic changes include alterations in morphology, drug resistance, pathogenicity, virulence, sporulation, and growth. Entomopathogenic fungi are one of the integrated pest management agents as an alternative to conventional insecticides. Mycoviruses have the potential as supportive agents, enhancing the efficiency of the insecticidal activity of the fungi. Studies about mycoviruses themselves and their interaction with their hosts, especially entomopathogenic fungi, are needed to realize their full potential. In this work, the sequence of the dsRNA element isolated from the entomopathogenic fungus Metarhizium pinghaense 4-2 strain was determined. Through this study, we report the sequence of a dsRNA virus isolated from the Metarhizium pinghaense for the first time. In further studies, the ORF of the mycovirus that induces a phenotype change in the host will be researched.

마이코바이러스는 곰팡이를 감염시키는 바이러스로 자낭균류, 담자균류 및 난균류에서 주로 발견되며 일부 의 경우 곰팡이의 표현형에 영향을 끼치는 것으로 알려져 있다. 이번 연구에서는 대한민국 토양 샘플에서 분리된 65개의 자낭균류 및 접합균류 균주의 전체 핵산을 추출하고, 전기영동을 통해 바이러스 특이적 밴드를 스크리닝 하였다. 스크리닝 결과 65개의 균주 중에서 Tolypocladium spp. 균주 2개와 Marquandomyces marquandii 균주 1개에서 바이러스 특이적 밴드를 발견하였다. 그 후, Cellulose Chromatography를 이용하여 double-stranded RNA 를 분리하고 DNase I 및 S1 Nuclease 처리를 통해 DNA와 single-stranded RNA를 제거하여, Tolypocladium sp. 균주 1개와 Marquandomyces marquandii 균주에서 발견한 특이적 밴드가 dsRNA임을 확인하였다. 추후 virus-free isogenic line을 확보하여 virus 유무에 따른 표현형 변화를 확인하고, 마이코바이러스와 곰팡이 간의 상호작용에 관해 연구할 계획이다.

Aphids are well-known insect pests that, due to their feeding habits, affect various crops' productivity and marketability. Additionally, they cause significant damage worldwide as vectors of viruses. Chemical pesticides are widely used to control these agricultural pests. However, due to resistance to various chemical pesticides, pest control is becoming difficult in agricultural environments. Entomopathogenic fungi such as the genus Metarhizium and Beauveria are being extensively researched as alternatives to these chemical pesticides. In this study, the mycological properties of isolated from soil Metarhizium pemphigi IPBL-H and the insecticidal activity of this strain against Myzus persicae and Aphis gossypii were evaluated for potential of development as a biopesticide.

Cryptotympana atrata belongs to the family Cicadidae, has long been recognized as a damaging plant-sucking pest, and is distributed in East Asian countries. In addition, their cries cause direct harm to us through noise pollution and also reported twig damage in the forest environments. In this study, we isolated strains of the entomopathogenic fungus Metarhizium that occurred from C. atrata collected this year. Here, we provide the morphological character and molecular phylogenetic relationship of this species. This is the first record of the entomopathogenic fungus Metarhizium viridulum isolated from C. atrata in Korea and provides a candidate strain with potential use for biological agents.

This study was conducted to analyze seasonal and annual variations in rice quality and factors affecting the quality, for quality evaluation of the brand rice varieties produced in Jeonnam region. Coefficient of variation (CV) values for the seasonal variation in the rice quality were 3.1% in Toyo value, 2.1% in whiteness, 1.6% in protein content, 1.0% in moisture content, and 0.4% in head rice ratio. Quality characteristics of the brand rice varieties generally showed a decreasing tendency after April, as the months progressed. CV values for the annual variation in the rice quality were relatively high at 5.6% in protein content and 5.2% in Toyo value whereas those for whiteness and head rice ratio were relatively low, at 2.7% and 1.8%, respectively. Palatability and protein content showed high correlations with minimum air temperature, sunshine hours, rainfall, and daily temperature range. Head rice ratio had a negative correlation with daily temperature range whereas chalky rice ratio had a positive correlation with rainfall. Based on these results, we formulated a multiple regression equation to estimate palatability of cooked rice using protein content, whiteness, head rice ratio, and moisture content as follows:y ＝－6.71a ＋ 2.27b ＋ 1.29c ＋ 0.51d － 15.34 (R2=0.51*)(y: palatability of cooked rice, a: protein content, b: moisture content, c: whiteness, d: head rice ratio).

“Unmi” is a new japonica rice variety developed by the rice breeding team of Honam Agricultural Research Institute, NICS, RDA in 2007. This variety was developed from a across between Samcheonbyeo with lodging and cold tolerance and HR17870 derived from the cross of Iksan435 (Sobibyeo) and Sangju17 with resistance to diseases and good quality. This variety has about 110 days of growth duration from transplanting to harvesting in northern plain, northern and southern mid-mountainous areas of South Korea. It is about 68 cm in culm length and tolerant to lodging. In reaction to biotic and abiotic stresses, it shows moderate resistance to blast, and to bacterial blight pathogen races from K1 to K3, but susceptible to other major diseases and insect pests. The milled rice of “Unmi” is translucent and has relatively clear non-glutinous endosperm and medium short grain. It has about 17.3% amylose content, 6.3% of protein and similar palatability of cooked rice compared with Odaebyeo. The milled rice yield performance of this variety is about 5.16 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. “Unmi” would be adaptable for ordinary transplanting in the northern plain, northern and southern mid-mountainous area of South Korea.

“wangkeumbora”is a new japonica rice cultivar developed from a three way cross of Jinbubyeo, Odaebyeo and Fukei126 at Honam Agricultural Reaserch Institute (HARI), NICS, RDA, in 2006. This cultivar has about 110 days growth duration from transplanting to harvesting under Korean climate condition. The milled kernel of “wangkeumbora”is translucent with non- glutinous endosperm. Amylose content of “wangkeumbora”is about 19.3%. “wangkeumbora”has better palatability of cooked rice compared with “daebyeo”and shows high resistant reaction to the blast, but susceptible to major diseases and insect pests. The milled rice yield of "Hwangkeumbora" is about 5.37 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. “wangkeumbora”would be adaptable for ordinary transplanting in northern plain, mid-mountainous and southern mountainous of Korea.

Hwangeumnodeul is a new japonica rice cultivar developed from a cross between Milyang165 and HR15151-B-21-3 at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2007. This cultivar has short grains and about 139 days of growth duration from direct seeding to harvesting in the southern plain areas. Culm length of this cultivar is 78 cm and the number of spikelet per panicle is similar to that of the check cultivar, Nampyeongbyeo, while filled grain rate is lower than the check variety. This cultivar is moderately resistant to leaf blast, bacterial blight pathogens of K1, K2 and K3 and stripe virus but susceptible to major virus diseases and insect pests. Milled kernel of Hwanggeumnodeul is translucent with non-glutinous endosperm. This cultivar has about 5.7% and 18.6% of protein and amylose contents, respectively. Palatability of cooked rice of Hwanggeumnodeul is similar to Nampyeongbyeo. Its milling recovery and head rice were 75.6% and 90.0%, respectively. Hwanggeumnodeul yielded 5.69 and 5.61 MT/ha in milled rice at the under wet-direct and dry-direct seeding conditions, respectively which are 17% and 12% higher than the check variety, Juanbyeo. It yielded 5.86 MT/ha, 8% higher than Nampyeongbyeo at the standard fertilizer level of the ordinary transplanting cultivation. “wanggeumnodeul”would be adaptable for ordinary transplanting as well as direct seeding in the southern plain including Chungcheong province.

‘nnuri’is a japonica rice cultivar developed from the cross between ‘ilyang 165’and HR14732-B-67-2-3 at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2005. This cultivar has a short grain shape and about 121 days growth duration from transplanting to harvesting in Korean climate condition. In reaction to biotic and abiotic stresses, it shows resistance to blast, bacterial blight pathogen from K1 to K3 and stripe virus, but susceptible to other major diseases and insect pests. The milled kernel of ‘nnuri’is translucent with non-glutinous endosperm. It has about 18.6% of amylose content and better palatability of cooked rice compared with ‘hucheongbyeo’cultivated in Kyunggi province. The milled rice yield of ‘nnuri’is about 5.94 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. ‘nnuri’would be adaptable to southern plain of Cheonan, middle-northern plain, and southern mid-mountainous of Korea.

A reaction of 214 lines and varieties to BB korean race K1, resistance and moderately resistance was 33 varieties which were bred before in 1990, susceptible were 5 varieties (Milyang23, Dongjinbyeo, Sinseonchalbyeo, Changseongbyeo and Cheongmyeongbyeo). Among bred after in 1990 resistance appeared 58 varieties, 18 varieties were susceptible. Bred after in 2000 were 50 varieties appeared resistance and 5 varieties were susceptible (Manho, Goun, Jinbong, Josaengheugchal, and Manna). Accordingly most varieties bred in south korea seemed to possession resistance to BB korean race K1. As a result of whether or not having Xa1 gene of rice varieties by SNP marker appeared that 43 varieties and the other 10 lines and varieties have Xa1 gene. Varieties bred before in 1990 have 18 (62.1%) varieties out of 29 varieties possession Xa1 gene to showed resistance to BB korean race K1, 19 (47.5%) varieties bred in 1990~2000, 6 (12.8%) varieties (Boseogchal, Daepyong, Hanareumbyeo, Hopyeongbyeo, Jongnam, Kuman) bred after in 2000 seemed to possession Xa1 gene.

The changes of the amino acid content including proline and protein content in response to NaCl treatment were investigated in between the salt-resistant variety CI5309 and salt-susceptible variety IR28 of rice. The amino acid contents such as -aminoapid