• International Journal of Industrial Entomology and Biomaterials
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• 제6권1호
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• pp.103-106
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• 2003

Among silkworm diseases, white muscardine is the most virulent and contagious disease caused by Beauveria bassiana and common during winter and rainy seasons. The disease is managed at present by practicing the silkworm body and rearing seat disinfection to prevent the spread of white muscardine during silkworm rearing as the available methods do not cure the silkworms against white muscardine. The use of systemic fungicide was suggested recently to control white muscardine. The present study investigated the practicability of application aspect of systemic fungicide as spray, It is observed that 3 times feeding of systemic fungicide through mulberry leaf, fed immediately after third, fourth moult and on $4^{th}$ day of final instar as most effective in suppressing the multiplication of the fungus in silkworm. Spraying of the systemic fungicide on mulberry in the rearing house, air-dried and feeding was suggested as suitable application method. Alternately the spraying of the systemic fungicide on mulberry in mulberry garden 6 hrs prior to feeding was also suggested as a method for the control of white muscardine in silkworm rearing.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.57-61
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• 2009

Three years($2004{\sim}2007$) survey was conducted on the incidence of silkworm diseases namely, Grasserie, Flacherie, Muscardine and Uzi fly, a silkworm pest with 150 sericulture farmers in the districts of Chittoor and Anantapur in Andhra Pradesh. The data revealed that grasserie and flacherie incidence were maximum in summer season and minimum in winter season whereas muscardine was observed high in winter season in both the areas and rarely in rainy season in Chittoor and Anantapur districts. An improvement of 11.16 and 7.6 kg cocoons/100 dfls were recorded in the batches of PM xCSR2 Diseases free layings(Dfls) reared in rearing houses disinfected with 2% bleaching powder and Ankush, a plant based bed disinfectant applied as per schedule, respectively. The Uzi fly incidence was suppressed by 61.02% in batches where the integrated package was adopted for control of Uzi fly infestation.

• 한국잠사곤충학회지
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• 제42권1호
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• pp.28-30
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• 2000

Red muscardine (P. fumosoroseus), first observed on silkworm in Korea, was examined on its cultural characters, infection process, and symptoms. The fungus on PDA medium was grown to 44 mm in diameter in 14 days. Conidiaphore ws 1.45$\mu\textrm{m}$ in diameter, producing 4 to 6 phialides (5.9$\mu\textrm{m}$${\times}$1.8$\mu\textrm{m}$) in cluster. Elliptic conidia wre hyaline and 2.9${\times}$1.3$\mu\textrm{m}$ in size. Diseased silkworm showed typical symptoms of muscardine while becoming stiff. On 3 to 4 days after inoculation of P. fumosoroseus conidia upon the surface of silkworm, it was observed that the silkworm moved and ate less in rearing bed, and amorpnous dark spots of 1∼2 mm appeared on the surface o thorax, abdomen, spirace, and etc. Corrected mortality reached up to 97% at 9th day after inoculation.

• International Journal of Industrial Entomology and Biomaterials
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• 제5권2호
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• pp.171-174
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• 2002

Two systemic fungicides, SF1 (Bavistin, a carbandazim fungicide 50% WP, Rallis India ltd., India) and SF2 (Bayleton 25% WP-Triadiamefon, a Triazole compound, Rallis India Ltd., India) were screened for control of muscardine disease in silkworm, Bombyx mori. One and two percent of SF1 and 0.05 and 0.1 % of SF2 in aqueous solution were found to be effective in in vivo condition for the control of the disease. These fungicides, on feeding through mulberry leaves continuously for two days to 4$^{th}$ and 5$^{th}$ instar silkworm larvae inoculated topically with conidia of Beauveria bassiana (4$\times$10$^{6}$ conidia/ml) resulted in reduction in mortality due to muscardine by over 90% as against 100% mortality in inoculated control. SF1 at 1% reduced the mortality by 90% in 4$^{th}$ instar and 91% in final instar silkworm while at 2%, the reduction was 92% and 96%, respectively. SF2 at 0.05 and 0.1 % concentration reduced the mortality by 82 and 88% during 4$^{th}$ instar and by 88 and 92% during 5$^{th}$ instar, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• 제48권1호
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• pp.42-47
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• 2024

The value of silkworms as functional health food materials has increased, as has the interest in its disease control for stable production, and in the economic value of entomopathogenic microorganisms. In this study, we isolated and identified disease-causing fungi from white muscardine silkworms, and confirmed whether this strain could produce white muscardine silkworms. For the analysis of the cause of white muscardine disease in the infected silkworms, the fungi and prokaryotes causing the disease were identified, isolated, and identified using metagenome analysis. Metagenomic analysis detected a large amount of the fungus Metarhizium rileyi in silkworms, and a large amount of the bacterium Enterococcus mundtii, which was presumed to be the causative agent of the disease. For accurate identification of the fungi, these were purified by culture medium, and sequencing and phylogenetic tree analyses were performed using an internal transcribed spacer. As a result, M. rileyi, Cladosporium cladosporioides, and C. tenuissimum were identified. In general, M. rileyi is known to form green conidia, but in this study, white-yellow conidia were formed, indicating that the exact causative agent of the fungal disease cannot be estimated by diagnosing the symptoms. Thus, a diagnostic method is necessary for the continuously collection of required pathogens, and identifying their morphological and genetic characteristics.

• 한국잠사곤충학회지
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• 제3권
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• pp.45-49
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• 1963

이 시험은 예비시험에 지나지 않고 그 병원성에 대하여서는 익년에 다시 하여야 한다. 그러나 지금까지 하여온 결과를 종합하여 요점을 들면 다음과 같다. (1) 누에의 녹강병과 야외곤충의 경화병 시체는 공통된 병원균 Nomuraea pracina와 Isaria spp에 의하여서 걸리는 것이라고 짐작이 된다. (2) 송충이는 Isaria spp에 의하여 이미 그 구제방법으로 실시하고 있어서 다른 야외 곤충에도 그 포자가 전파되어 있음을 짐작할 수 있다. (3) 흰불나방 유충은 경화병균에 의하여 침범되지 않는 것 같다.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권2호
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• pp.81-85
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• 2007

White Muscardine is the most common fungal disease of silkworm, Bombyx mori L. caused by the pathogenic fungus, Beauveria bassiana (Balsamo) Vuillemin. In the present investigation, an attempt has been made to screen locally available medicinal/ weed plants against Beauveria bassiana. Among the plant extracts (PE) tested, 5% aqueous crude extract of the bulb of Allium sativum (Garlic) has been found to be most effective against Beauveria bassiana. The radial growth of Beauveria bassiana in vitro was inhibited to the tune of 54.9% in aqueous extract and 54.4% in ethanolic extract of Allium sativum and correspondingly mycelial dry weight gave rise to 110.7 mg and 108.7 mg against 201.7 mg in control 15 days post treatment. Similarly, silkworm larvae topically inoculated with the Beauveria bassiana conidia ($1.8{\times}10^6/ml$) registered survival up to 53.0% against 0.0% in control after treatment with aqueous extract of Allium sativum. Simultaneously, as a preventive measure, silkworm larvae were put to rear in conidia contaminated seat paper instantly treated with aqueous extract of Allium sativum that also increased survival up to 61.0% against 4.6% in control. It is also observed that the plant extract is absolutely innocuous to silkworm.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.229-234
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• 2004

Six entomopathogenic fungus isolates, Beauveria bassiana J57A, Nomuraea rileyi J125A, Paecilomyces farinosus J3A, Paecilomyces fumosoroseus J50A, Metarhizium anisopliae J88, Aspergilius sp. J64A, causing muscardine disease and aspergillosis in the silkworm, Bombyx mori were investigated for their cultural and morphological characteristics (on PDA culture media within 14 days at $24^{\circ}C$). The results showed that they differ each other from the features of cultural characteristics (colony elevation, colony color, colony growth rate) or morphological characteristics (conidiogenous cell structure, phialides, conidia size and shape). Among cultural characteristics, colony color is the easiest recognizable character between isolates. The morphological characteristics of each fungal isolate correspond to the descriptions of current system of classification.

• 한국잠사곤충학회지
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• 제4권
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• pp.103-105
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• 1965

금년춘잠시육시 발생한 경화병잠에서 Beauvia Bassiana(Bols) rull, formma malvaceorosea Miyake에 유사한 것을 분리 관찰하였다

• 한국잠사곤충학회지
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• 제32권2호
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• pp.105-109
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• 1990

포르말린에 과망간산카리(KMnO4)를 넣어 화학적 반응에 의하여 발생되는 포름알데히드 가스로 누에고름병 바이러스의 불활화와 흰굳음병균에 대한 소독시험을 실시하여 다음과 같은 결과를 얻었다. 1. 누에고름병 바이러스(Nuclear polyhedrosis virus)의 불활화는 잠실면적 3.3$m^2$당 포르말린 25$m\ell$에 과망간산카리 10g을 혼합하여 하룻방 동안 훈연소독을 실시하였을 때 상당한 수준의 소독효과가 있었고 같은 잠실단위 면적에 포르말린 75$m\ell$와 과망간산카리 30g을 혼합하여 하룻밤 동안 훈연상태를 유지하였을 때는 거의 완전한 불활화가 이루어졌다. 2. 노란굳음병균에 대한 살균효과는 잠실면적 3.3$m^2$당 포르말린 50$m\ell$에 과망간산카리 20g을 반응시켜 훈연소독을 실시하였을 때는 처리받은 균의 자람이 상당한 수준 억제되었고 같은 단위면적에 포르말린 75$m\ell$와 과망간산카리 30g을 혼합시켰을 때는 완전한 살균이 이루어졌다. 3. 포르말린 훈연소독에 의한 누에에 미치는 영향은 4령 1일째와 5령 1일째 2회와 4령 1일째, 5령 1,3일째 각 1회씩 3회를 처리하였을 때(훈연소독은 저녁급상후에 실시하고 다음날 아침 급상때까지 유지시킴) 전견종, 견층중, 견층비율, 유충기간(4-5령) 등에서는 무처리와 차이가 없었으나 3회 처리시에는 실품림새율은 무처리에 비하여 약간 떨어졌다.