• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.310-319
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• 2017

This study categorized the damaged trees by Supervised Classification using time-series-aerial photographs of Bukhan, Cheonggae and Suri mountains because oak wilt disease seemed to be concentrated in the metropolitan regions. In order to analyze the spatial characteristics of the damaged areas, the geographical characteristics such as elevation and slope were statistically analyzed to confirm their strong correlation. Based on the results from the statistical analysis of Moran's I, we have retrieved the following: (i) the value of Moran's I in Bukhan mountain is estimated to be 0.25, 0.32, and 0.24 in 2009, 2010 and 2012, respectively. (ii) the value of Moran's I in Cheonggye mountain estimated to be 0.26, 0.32 and 0.22 in 2010, 2012 and 2014, respectively and (iii) the value of Moran's I in Suri mountain estimated to be 0.42 and 0.42 in 2012 and 2014. respectively. These numbers suggest that the damaged trees are distributed in clusters. In addition, we conducted hotspot analysis to identify how the damaged tree clusters shift over time and we were able to verify that hotspots move in time series. According to our research outcome from the analysis of the entire hotspot areas (z-score>1.65), there were 80 percent probability of oak wilt disease occurring in the broadleaf or mixed-stand forests with elevation of 200~400 m and slope of 20~40 degrees. This result indicates that oak wilt disease hotspots can occur or shift into areas with the above geographical features or forest conditions. Therefore, this research outcome can be used as a basic resource when predicting the oak wilt disease spread-patterns, and it can also prevent disease and insect pest related harms to assist the policy makers to better implement the necessary solutions.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.263-266
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• 2011

Crop protection strategies in organic horticulture aim to prevent insect pest and plant disease problems through utilization of non-chemical based control means. In order to develop a model for management of plant diseases and insects in organic cucumber cultivation, we compared efficacies between chemical pesticide spraying system and biological control means in semi-forcing and retarding cucumber cultivation during 2005 and 2006. Conventional chemical spray program using various chemical pesticides was applied 5 - 10 days intervals, while two different non-chemical pesticide application programs using two formulated biopesticides Topseed$^{TM}$ and Q-fect$^{TM}$, Suncho$^{TM}$, and Sangsungje$^{TM}$ (biocontrol agents 1) and using egg-yolk and cooking oil(EYCO), Bordeaux mixture, Suncho$^{TM}$, and Sangsungje$^{TM}$ (biocontrol agents 2) were applied 5 - 7 days intervals during entire cucumber cultivation period. Efficacy of both biocontrol agents programs was effective to comparable to conventional chemical pesitice spray program to control plant diseases such as powdery mildew and downy mildew as well as insect pests such as aphids and thrips which are known as major threats in cucumber organic cultivation. In this study, we established and evaluated an effective and economic crop protection strategy using various biological resources can be used to control plant diseases and pests simultaneously in organic cucumber cultivation field.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.547-559
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• 2007

Bacillus thuringiensis (Bt) was first described by Berliner [10] when he isolated a Bacillus species from the Mediterranean flour moth, Anagasta kuehniella, and named it after the province Thuringia in Germany where the infected moth was found. Although this was the first description under the name B. thuringiensis, it was not the first isolation. In 1901, a Japanese biologist, Ishiwata Shigetane, discovered a previously undescribed bacterium as the causative agent of a disease afflicting silkworms. Bt was originally considered a risk for silkworm rearing but it has become the heart of microbial insect control. The earliest commercial production began in France in 1938, under the name Sporeine [72]. A resurgence of interest in Bt has been attributed to Edward Steinhaus [105], who obtained a culture in 1942 and attracted attention to the potential of Bt through his subsequent studies. In 1956, T. Angus [3] demonstrated that the crystalline protein inclusions formed in the course of sporulation were responsible for the insecticidal action of Bt. By the early 1980's, Gonzalez et al. [48] revealed that the genes coding for crystal proteins were localized on transmissible plasmids, using a plasmid curing technique, and Schnepf and Whiteley [103] first cloned and characterized the genes coding for crystal proteins that had toxicity to larvae of the tobacco hornworm, from plasmid DNA of Bt subsp. kurstaki HD-1. This first cloning was followed quickly by the cloning of many other cry genes and eventually led to the development of Bt transgenic plants. In the 1980s, several scientists successively demonstrated that plants can be genetically engineered, and finally, Bt cotton reached the market in 1996 [104].

• Entomological Research
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• v.48 no.5
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• pp.354-361
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• 2018

Plant essential oils (EOs) exhibit an array of biological activities against insect pests. However, their negative influences on the pheromonal activity of azuki bean beetle (ABB), Callosobruchus chinensis L. have not received research attentions. ABB is a field-to-storage pest of legumes, and its female produces the sex pheromone known as homofarnesal with two isomeric components: 2E- and 2Z-homofarnesal, (2E,6E)-7-ethyl-3,11-dimethyl-2,6,10-dodecatrienals and (2Z,6E)-7-ethyl-3,11-dimethyl-2,6,10-dodecatrienals. We evaluated the effects of three EOs and their two major components on the attractiveness of male ABBs to synthetic homofarnesal (2E-:2Z-homofarnesal = 6:4) using Y-tube olfactometry in laboratory and rocket traps in the semi-open polyhouse. Y-tube olfactometry showed the significant negative effect of EOs of Illicium verum, Croton anisatum at 10 and 100 ng, and Gaultheria fragrantissima at 100 ng against homofarnesal (100 ng) in attracting male ABBs. Similarly trans-anethole (at 10 and 100 ng) and methyl salicylate (at 100 ng) also ascertained significant negative effect against homofarnesal (100 ng) in Y-tube olfactometry. When 10 mg of each of trans-anethole and methyl salicylate was released at the downstream of 30 mg homofarnesal lure in rocket traps, highly significant effect was achieved against attractiveness of homofarnesal to ABB males. This study ascertained significant level of negative effect of the tested EOs and their major components to homofarnesal, tracing out a new opportunity of integrating them in ABB management programs both in field and storage.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.157-169
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• 2014

Between 2010 and 2012, diseases and insect pests of sweet persimmon were surveyed at sweet persimmon export complexes and non-export orchards in Suncheon, Jeonnam Province; Jinju, Changwon (Dongeup and Bukmyeon), and Gimhae, Gyeongnam Province; and Ulzu, Ulsan. The following diseases were found in the sweet persimmon orchards: angular leaf spot (Cercospora kaki), anthracnose (Colletotrichum gloeosporioides and Colletotrichum acutatum), circular leaf spot (Mycosphaerella nawae), powdery mildew (Phyllactinia kakicola), and gray mold (Botrytis cinerea). Circular leaf spot was the most frequent and serious disease, and C. gloeosporioides and C. acutatum were found on fruits. Thirty-three insect pest species that belonged to 32 genera of 20 families in 5 orders were found in the sweet persimmon orchards; the two-spotted spider mite, Tetranychus urticae, was also found in the surveyed orchards. Apolygus spinolae, Pseudaulacaspis cockerelli, and Adoxophyes orana were widely found in the surveyed orchards; Spodoptera litura and Homona magnanima were also recorded. Damage by insect pests was low, and the quarantine insect pests peach pyralid moth (Dichocrocis punctiferalis) and persimmon fruit moth (Stathmopoda masinissa) were rarely or not found in the sweet persimmon export complexes. In addition, other quarantine insect pests, such as persimmon false spider mite (Tenuipalpus zhizhilashviliae) and Japanese mealybug (Planococcus kraunhiae), were not detected. These quarantine insect pests were also not found in the sorting places, storage houses, and fruits for export; however, scale insects and two-spotted spider mites were found at a low rate. Although anthracnose (C. acutatum) infested fruit was found in the storage houses, only one in Jinju and Gimhae.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.67-76
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• 2014

The objective of this study is to estimate the economic value of official management and control for invasive insects and diseases in fruits. The direct and indirect effect of this control measure can be the changes in price of fruits and related goods, changes in export volume of domestic fruits, changes in total volume of fruit production, and reduce the risk in food safety. The contingent valuation method with the single-bounded dichotomous choice is employed to estimate each household's willingness-to-pay (WTP) to maintain official management and control measures. The total number of sample consists 2,050 respondents between the ages of 19-60 years, and the survey is conducted using Web-based survey. The estimated results for mean WTP is 5,443won per month per household. Therefore, the total economic value of official management and control on fruit in Korea is estimated to be approximately 94.4 billion won per month.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.3
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• pp.107-113
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• 2003

Ecological control can contribute to the sustainibility of vegetation management systems by reducing the input currently derived from non-renewable fossil energy sources. The use of turfgrass mixtures is an important tool in turf management. Turfgrass mixtures of two or more compatible and adapted species provide improved tolerance to pest and environmental stress, more so than monostands. The objectives of this study were to evaluated turf insects, pests and zoysia large patch control by turgrass mixtures. In April 2001 and 2002, plots were inoculated with 50g of Rhizoctonia solani AG2-2LP inoculum. Inoculum were treated within a 29cm diamater circle at Zoysia japonica, Zoysia japonica, Poa pratenis, or Festuca arundinacea mixtures. After four weeks, disease severity in each plot was determined. plot area visual ratings were assessed visually on a linera 0 to 100%. In August 2001 and October 2002, turf insects and pests in each plot were investigated in 10cm deep soil cores with 8cm diameters using hole cut. Zoysia large patch affected zoysiagrass monostands more severly than zoysiagrass and cool-season turfgrasses mixtures. It was suggested that the barrier effect of cool-season turfgrass suppressed zoysia large patch in the mixture of zoysiagrass and cool-season turfgrasses. Also, warm-season and cool-season turfgrasses mixtures suppressed insect populations more efficiently than warm-season turfgrass monostands.

• Journal of Environmental Policy
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• v.13 no.4
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• pp.135-159
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• 2014

Industrial insect is defined as the insect utilized in industries that creates added value. Most of the industrial insects used in Korea are exotic species that are introduced through artificial means. Despite the rapid expansion of market for industrial insects, the system for risk assessment of industrial insects is not being adequately conducted. Although Korea carries out a risk assessment for the species designated as disease and insect pest by Animal and Plant Quarantine Agency, far too little consideration is being given to overall ecosystem, as the control system is covered in the Plant Quarantine Law. To solve this problem, we analyzed the Korean risk assessment system and looked at systems in other countries. The results show that it is essential for stakeholders to reach an agreement to set up fundamental directions for the system. Unless the integration system of taxonomical and ecological information is prepared, the ecological risk assessment should be conservative to protect ecosystems and should also follow the precautionary principle. It also requires cooperation among the ministries. In addition, the results indicated that a differentiation between risk assessment and screening is urgent. Several solutions such as setting up clear objectives in both assessment and screening stages, target species, steering organization and assessment criteria assessment systems from were proposed as practical institutional strategies. Among many foreign countries the assessment system from Ireland equally considers various factors such as economical, ecological safety and management aspects, It is also based on precautionary principle to fulfil its original purpose. It was suggested that the Ireland system would be the best reference that can be modified and applied into the Korean system by considering distinct characteristics of the industrial insects.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.333-339
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• 2020

Pheromone-based techniques are becoming a viable strategy of insect pest management as facilitated by the exponential increase in numbers of pheromone identifications from many insect pests. This is the report on the efficacy of pheromone-mediated chemical communication disruption (PCD) technique against the Korean population of smaller clearwing moths, Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae) using its female sex pheromone component, (Z, Z)-3, 13-octadecadien-1-ol. The PCD trials were carried out four times during 2016 and 2017 in persimmon orchards located at Suncheon and Jinju Cities in Korea, and the PCD efficacy was expressed as the mean differences in the seasonal catches of S. tenuis males in the PCD and control plots. The seasonal male moth catches in monitoring traps installed in the PCD plots were significantly lower as compared with those installed in the control plots. Consequently, the PCD efficacy in the experimental orchards ranged from 95.2-100% with an average efficacy of 98.8 ± 1.2%, revealing a future possibility of pheromone-based management of S. tenuis.

• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.199-202
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• 2007

This study was carried out to provide pest control information for the cultivation of Eleutherococcus senticosus Max. As a result of investigation of the diseases and insect pests, three pathogens and three insect pests were identified from the field sample, respectively. The identified insects pests were aphids, stinkbugs and Bothrogonia japonica. Occurrenre peaks of aphids were occurred on June and August, and generally young leaves and flower buds were injured mainly. The identified diseases were black ring spot caused by Phoma sp., gray mold caused by Botrytis cinerea and leaf blights caused by Rhizoctonia solani. The black ring spot was the most severe disease and was investigated from the beginning of June, and the incidence of the disease was 30% higher than that on September. As a result of growth test under different temperature conditions on PDA, these pathogens showed the best mycelial growth rate between 25 $^{\circ}$C and 30 $^{\circ}$C, and these results indicate that these diseases occur on hat summer season.