Entomopathogenic fungi have been used to control pest as alternative to chemical pesticide. To kill the pest entomopathogenicfungi penetrate cuticle of pest, reach the hemocoel and utilize nutrient of host pest. Finally fungi kill the host by consumingthe host nutrient and physically damaging the tissues. But these process of fungi to control pest is needed so much timeand this point is a disadvantage for fungi. Therefore we studied other application method of fungi to control pest. Weconducted behavior test of beet armyworm to Isaria fumosoroseus which is high virulent against beet armyworm. Adultof the beet armyworm avoided oviposition at Chinese cabbage treated with I. fumosoroseus compare to control and otherhigh pathogenic isolate, Metarhizium anisopliae and this repellency of I. fumosoroseus lasted for 5days in greenhouse.Behavior of larvae to I. fumosoroseus also investigated with choice and non-choice test. Third to fifth instar larvae detectedand avoided fungi. Repellent behavior of larvae to fungi was more noticeable in younger larvae. This result may be usedto prevent the infestation of moth in crop production.

The diamondback moth, Plutella xylostella is one of the world’s major pests. Economic cost to control this pest wasestimated between US$1.3 billion and US$2.3 billion based on management costs. Conservative estimate included yieldloss caused by 5% diamondback moth was estimated US$4 billion-US$5 billion. P. xylostella was managed by chemicalinsecticide such as organophosphates, carbamates and pyrethroids. But insecticide resistance which is caused by repeatedapplication makes it difficult to control this pest. For environmental friendly control of diamondback moth, entomopathogenicfungi could be used as alternative. We conducted bioassay to select high virulent isolate to larva of diamondback mothwith forty six entomopathogenic fungi which were isolated from soil samples by insect-bait method. As a result of bioassaytwelve isolates was selected as candidate. We investigated control efficacy of these twelve isolates with potted Chinesecabbage at laboratory and greenhouse.

Entomopathogenic fungi have been used as important part of integrated pest management program to control aphid. In particular, Beauveria bassiana was distributed throughout the world including temperate and tropical area, various habitats from alpine soil, desert soil to running water and both insect and plant. Especially the fungus has also been isolated from the surface and the interior of plants and act as natural control agent. Viability of fungi on the plant surface may be influenced by temperature, humidity, sunlight and plant type as well as fungal isolate. Persistence of treated fungal control agent on phylloplane and control efficacy may differ from environmental conditions and isolates. In this study, we investigated the persistence of an B. bassiana which is developing as prototype wettable powder to control cotton aphid, and the residual efficacy of the prototype on cucumber under three different greenhouse conditions.

PURPOSES :Infiltration of moisture, polluted material, and deicer into concrete, accompanied by freeze and thaw can cause significant deterioration of concrete pavement. In order to protect concrete from deterioration, it is necessary to prevent the infiltration of these concrete external materials. The moisture-repellent agent, which is a surface treatment and maintenance material added to concrete structures to render them water resistant, has advantages such as prevention of water infiltration and security against air permeation. Nano-coat, which is referred to as silicon hydride, is typically used as a moisture-repellent agent. Therefore, in this study, an attempt is made to use penetration-type Nano-coat as an alternative in order to evaluate its applicability through environmental resistance tests.METHODS:This study aimed to evaluate the applicability of penetration-type Nano-coat, which can provide water repellency to concrete, in concrete pavements, through various environmental resistance tests such as freezing and thawing resistance, chloride ion penetration resistance, and surface scaling resistance tests. The applicability of penetration-type Nano-coat was demonstrated based on the specification of KS F 2711, KS F 2456, and ASTM C 672.RESULTS :In the case of penetration-type Nano-coat applied on sound concrete, an increase in concrete durability was demonstrated by the negligible chloride ion penetrability and the absence of scaling, as revealed by visual observation of the surface, after 50 cycles of scaling resistance test. In addition, test result of the application of penetration-type Nano-coat on deteriorated concrete established that concrete surface pretreated by grinding provided improved durability than non-treated concrete.CONCLUSIONS:This study indicates that penetration-type Nano-coat is applicable as an effective alternative, to increase the durability of concrete structures. In addition, it was known that pretreatment of deteriorated concrete surface, such as grinding, is required to improve the long-term performance of concrete pavement.

Cotton aphid, Aphis gossypii Gloever is one of the major pests on a wide range of economically important crops in the world. The sustained use of chemical insecticides to control the aphid has led to the emergence of resistant strains to numerous used insecticides. As an alternative strategy entomopathogenic fungi have been used as part of integrated pest management program to control aphid, especially insecticide-resistance population. In particular, Beauveria bassiana-based commercial bio-insecticide has been used to reduce the pest population under greenhouse conditions in various countries. In this study, we investigated the control efficacy of a prototype of commercial mycopesticide using an B. bassiana (wettable powder) against cotton aphid on potted cucumber plant in greenhouse conditions.

Various arthropods have directly and indirectly threatened human life by transmitting human pathogens such as malaria and Zika virus as well as by damaging crops such as direct feeding and transmission of plant pathogens. According to WHO, vector-borne diseases account for over 17% of all infectious diseases and there are over 1 million deaths from the diseases such as malaria, dengue, etc., globally. About 13% of total crop production is destroyed by agricultural pests during crop production and storage. To control medical or agricultural pests chemical pesticides have been used, but recently because of concerns about environmental pollution and human health the demands for eco-friendly control method are increasing. Insect pathogens are good alternative candidates instead of chemicals. Over 50 entomopathogens including viruses, bacteria, fungi and nematodes are now commercially used as microbial pesticides. Entomopathogenic fungi have also been evaluated as control agents for a diverse insect pests such as aphid, moth, thrip, whitefly, mosquitoes, tick, etc. We will discuss a development of microbial pesticides using, especially, entomopathogenic fungi to control noxious arthropods to agricultural crops and human.

Beet armyworm, Spodoptera exigua, diamondback moth, Plutella xylostella and tobacco cutworm, Spodoptera litura are the three most serious pests of many economically important crops such as cruciferous crops, various vegetables and ornamental plants. Because these pests are known to be resistant to lots of chemical insecticides, integrated control using both or either entomophathogen and/or natural enemy is thought to be an attractive alternative for effective control. One of the obstacles using and expanding mycopesticide is narrow host ranges. At commercial farms, cultivating crops are seriously damaged by various Lepidopteran pests. Farmers want to use a microbial control agent which can control various host insects to reduce cost and labor. In previous study, we selected two entomopathogenic fungi, Metarhizium anisopliae and Paecilomyces fumosoroseus, which shown high virulence against beet armyworm. For wide use of the isolates in farm, we tested its host ranges, especially to diamondback moth and tobacco cutworm, which also are serious pest in Korea. The two isolates were shown a good control effect in leaf disc bioassy.

Various insect pests and plant disease can outbreak in a field. For the effective control of pests and plant diseases during crop cultivation, farmers simultaneously or sequentially spray various eco-friendly agricultural materials (EFAM), chemical pesticides and microbial control agents on the same fields. It was reported that many agrochemicals are harmful to entomopathogenic fungi, especially some fungicides with broad spectrum activity that are routinely applied for the control of plant diseases. In addition, some pesticides may antagonize the potential insecticidal activity and efficiency of entomopathogenic fungi. Therefore, sometimes the utilization of fungal entomopathogen in forestry and agricultural production is limited because of the undesirable interference from some fungicides and pesticides. There is little research that examines the compatibility of these EFAMs with entomopathogenic fungi and the influence of EFAMs on the control efficacy of mycopesticides. We conducted a study of influence of pretreated eco-friendly agricultural materials on control efficacy of Isaria javanica isolate against sweet potato whitefly.

Microbe have been considered as potential control agents for pest, as alternative to chemical control methods. Among entomopathogens, fungi cause the mortality by penetrating the cuticle of pest and/or by metabolites such as toxin. Not only this direct control effect of fungi, but repellency of fungi also may be used to prevent the pest. Repellence effect of fungi is considered as inhibitory factor to control termite. A study was reported in Japan that termite was able to detect and remove the conidia of fungi on their surface. The termite can escape from fungal infection and protect their colony. There is few study that insect pest such as moth can detect and avoid the virulence fungi. Therefore, we has been conducting the detection and avoidance of beet armyworm to high pathogenic fungi, Paecilomyces fumosoroseus. Adult of the beet armyworm avoided oviposition at Chinese cabbage treated with P. fumosoroseus compare to control. This result may be used to prevent the infestation of moth in crop production.

Entomopathogenic fungus is a useful control agent to sucking type insect such as whitefly and aphid. The fungi are influenced by some environmental factors such as relative humidity, temperature and UV and cause slow and fluctuation in pest control efficacy. Especially, UV kills conidia or spores of entomopathogenic fungi and a mycopesticide using fungi has short control period in field. UV intensity changes from season to season. Survival rate of entomopathognic fungi treated may differ from seasons and will show different control efficacy. Therefore, we conducted a study to estimate the persistence of an Isaria javanica isolate, which was already reported as sweet potato whitefly control agent, in potted greenhouse soil planted different crops. The number of survival spore decreased gradually and differ from seasons.

As ubiquitous organisms entomopathogenic fungi may natually occur within environment including phylloplanes and soil or deposite and survive for a while after spraying a fungal suspension to control insect pest. The existence of pathogenic fungi is a threat to arthropods foraging for food and oviposition sites. The detection and avoidance of pathogens is important for host survival, longevity and ultimate fitness. Although entomopathogenic fungi are ubiquitous worldwide and act as common natural enemies of many invertebrate species, very few studies have conducted abiut the detection and avoidance of pathogenic fungi by insect pest. We have studied that an insect pest can recognize a high virulence fungi on crop surface, avoid oviposition and don’t enter the field treated their pathogen.

Entomopathogenic fungi are natural enemies of insect pests and contribute to the natural regulation of their host populations. These fungal group are often used as active ingredients for microbial insect pest control. In addition, the potential antimicrobial effect by entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have recently been reported against fungal plant pathogens. Dual microbial control effects with entomopathogenic fungi against both aphids and cucumber powdery mildew had reported in Canada. In our previous studies we conducted bioassay with entomopathogenic fungi to develop dual microbial control agent which can control both aphid and fungal plant disease. We selected an Beauveria bassiana isolate which has high dual control effects against both cotton aphid, Aphis gossypii and sclerotinia rot, Sclerotinia sclerotiorum. In this study, we have tested the dual control efficacy of the B. bassiana isolate against cotton aphid and sclerotinia rot on whole potted cucumber plants. We found that the B. bassiana isolate protected the plant from cotton aphid and sclerotinia rot under laboratory condition.

Insect pests have been a serious problem over many years and remain a major threat for food production. Although chemical pesticides are major pest control strategies, use of microorganisms such as entomopathogenic bacteria, fungi, viruses and nematodes have continuously increase last few decades to minimize the use of agrichemicals. According to BBC research, the global biocontrol market was about $2.1 billion in 2011, and this is expected to rise $3 ~ 4 billion by 2017. Over 50 entomopathogens are commercially produced and used augmentatively as microbial pesticides. About 175 biopesticide active ingredients and 700 products have been registered worldwide. Bacillus thuringiensis (Bt), Beauveria bassiana, Metarhizium spp., nuclear polyhedrosis virus and Steinernema spp. are the most popular control agents used in plant protection. Among the microbial control agents Bt products have more than 50% of market share. In Korea, only 13 environmentally-friendly crop protectants were registered for insect pest control in 2015. Market share is very low and has grown slowly. We will discuss how we can expand the market with our techniques.

Beet armyworm, Spodoptera exigua is difficult to control using chemical insecticides because of the development of insecticide resistance. Various control agents may use for eco-friendly beet armyworm managements, Entomopathogenic fungus is one of the promising control agents as an alternative to chemical control agent. At previous study we isolated a number of entomopathogenic fungi from soil samples and selected three entomopathogenic fungi, Metarhizium anisopliae FT83, Paecilomyces fumosoroseus FG340 and Metarhizium anisopliae FG344 which had high virulence against larva of beet armyworm. To select an isolate having high virulence at high temperature against S. exigua, thermophilic pest, we conducted bioassay at five different temperatures(15, 20, 25, 30, 35℃). These three isolates showed the high mortality and low LT50 at 30℃. To select substrate for mass production these isolates were inoculated(5×10⁴/㎖, 20㎖) at barley, unpolished rice, wheat bran and rice bran and incubated for 14 days at 25℃. Wheat bran showed highest conidia production of M. anisopliae FT83 and P. funosoroseus FG340 and barley was suitable for M. anisopliae FG344.

Various insect pests infest crops including vegetables and ornamentals during crop production. Chemical pesticides have generally used until recently to control pests. Many pests are very difficult to control using organic pesticides because of the development of insecticide resistance and their rapid population increase. Entomopathogens are the promising alternative control methods. Entomopathogenic fungi are good candidates to control sucking insects such as aphid, whitefly and mite because the fungi can infect without ingestion. Conidia or blastospores of fungal entomopathogens are sprayed onto target plant and/or insect, adhered on insect surfaces, and penetrated into hemocoel through insect cuticle. Then the fungus utilize insect nutrients and kill the host insect. During this process, fungus was influenced by environmental conditions such as temperature, relative humidity and UV light. These are causing slow mortality and preventing wider application and use of mycopescitide using entomopathogenic fungi. In addition, control efficacy with fungal entomopathogen differed fungal isolate and host insect. Therefore, we need to study selection of high virulence isolate, mass production, formulation and application techniques to develop mycopesticide.

지구 온난화에 따른 외기온도의 지속적인 상승은 젖소의 유질저하를 초래하는 것으로 알려져 있다. 현재 우리나라에서는 원유의 유지방함량, 체세포수 및 세균수를 기준으로 유대가격을 산정하고 있어 궁극적으로 여름철 온도의 상승은 젖소농가의 수익성에 악영향을 미치게 된다. 본 연구에서는 경북지역을 중심으로 외기온도와 상대습도을 조사하고 외기온도와 상대습도에 따른 온습도지수 (THI)를 도출하여 유질에 미치는 영향을 상관관계와 회귀분석 방법을 이용하여 분석하였다. 유지방 함량은 겨울철 4.0-4.1%에서 여름철로 접어들면서 3.6-3.7%로 저하하였고 동시에 온도와 THI가 상승하였다. 체세포수 1등급 출현율은 4-9월이 다른 달에 비해 낮은 것으로 나타났다. THI는 유지방 함량과는 r=-0.8914, 체세포수 1등급 출현율과는 r=-0.6067의 상관관계를 보였으나, 세균수 1등급 출현율과는 통계적으로 유의한 상관관계을 보이지 않았다. THI에 따른 유지방함량 및 체세포수 1등급 출현율을 예측할 수 있는 공식을 단순회귀분석법을 이용하여 도출하였다. 본 연구의 결과을 종합하면, 온도 및 상대습도를 이용하여 도출한 THI는 젖소의 고온스트레스를 분석하는 지표로 사용될 수 있을 것으로 사료된다.

Beet armyworm, Spodoptera exigua are difficult to control using chemical insecticides because of the development of insecticide resistance. For eco-friendly beet armyworm managements, various control agents are required. Entomopathogenic fungus is one of promise control agents as an alternative to chemical control agent. We isolated entomopathogenic fungi from soil samples of suwon by insect-bait method using Galleria mellonella and conducted bioassay to larva of beet armyworm. As a result of bioassay isolate FG274, FG340, FG344 had high virulence as 100% against second instar larva of S. exigua. To identify the fungus isolates, their’s morphological characteristic was observed and ITS of 18srRNA was sequenced. ITS sequence of FT274, 340, 344 were highly matched (100%) to that of Beauveria bassiana, Paecilomyces fumosoroseus, Metarhizium anisopliae. To investigate the optimal concentration, three isolates were sprayed at three different concentration(1×106 ,107 and 108 conidia/㎖) in laboratory conditions. 나타내었다.