In countries without strong biosecurity systems, Khapra beetle, Trogoderma granarium poses a continuing threat to agriculture. Even when quarantine laws exist, the risk is greater if one of the world's most serious pests becomes introduced to imported stored grain. The rate of Khapra beetles introduced is rising sharply with increased transport, trade, travel, and tourism between countries and continents. Species identification is usually the key to success in Khapra beetle control programs. Countries that export/import grains, such as Australia, Canada, Russia, Korea and USA, must ensure that their ports, grain storage facilities, and transportation systems are free of khapra beetle. Researchers so far developed effective quarantine treatments and eradication strategies to deal with khapra beetle infestations that occur upon import at inland port. Khapra beetle introductions are likely to be impacted by a variety of factors, including trade flow and quarantine laws. In this study, we provide an overview of the current global quarantine laws, invasions of khapra beetle, and its control strategies.
Numerous Dermestidae insects are considered significant pests because of their capacity to inflict substantial economic harm on stored food items. Trogoderma and Attagenus genera members are commonly discovered in imported grain and other food products. Usually, infestations of these species consist of various species that reproduce quickly and spread effortlessly. The small size of Attagenus and Trogoderma stored-product stages makes it extremely challenging to identify them based on their morphological characteristics. Hence, it is imperative to have precise identification techniques in place to ensure the safety and dependability of the grain industry, as well as to streamline efficient plant quarantine measures. Various molecular methods have been employed for insect species identification, such as restriction fragment length polymorphism (RFLP), amplified fragment length polymorphism (AFLP), random amplified polymorphic DNA (RAPD), single-strand conformation polymorphism (SSCP), DNA sequence analysis, and species-specific primer PCR (SS-PCR) techniques. Despite the considerable focus on quickly identifying these species in stored products in recent years, there is a notable absence of systematic molecular identification. This research highlights the use of genetic techniques to differentiate between Trogoderma and Attagenus species.
Fruit Flies (Diptera: Tephritidae) are polyphagous, highly invasive pests in which female adults lay eggs under the skin of fruit and larvae damage the fruit. Among them, the Oriental Fruit Fly, Bactrocera dorsalis (Hendel) was first reported in Taiwan and is distributed throughout much of Southeast Asia, including Vietnam, as well as on the African continent and in the Pacific region. In order to prevent the introduction of pests into country, the Animal and Plant Quarantine Agency has designated them as prohibited pests and is conducting surveillance and investigation on their occurrence. The experimental countries were Taiwan and Vietnam, and statistical analysis was conducted based on the number of B. dorsalis caught by setting up traps for about 8 months. Methly eugenol (ME; 4-allyl-1,2-dimethoxy-benzene) is a widely distributed natural plant and is used because it strongly attracts males of B. dorsalis. The experiments aimed to verify the effect of attractant formulations (liquid, solid, wax) and traps (Delta trap, Lynfield trap, Steiner trap) on B. dorsalis.
After detection of red imported fire ant (Solenopsis invicta) at Gamman port in Busan in September of 2017, Animal and Plant Quarantine Agency has surveilled invasive ants in the area with a high invasion risk of ants. However, existing surveillance traps have several limitations such as captured ants could escape easily or it is very hard to set up the trap on a hard ground like concrete or asphalt. To solve these problems, we developed a new trap using multiple narrow tubes to attract ants to the inside of the trap and make it hard for ants to escape. The new trap can be easily set up under various conditions. The new trap has more than four times ant capturing efficacy compared to conventional pitfall traps. Our results confirmed that the new trap could prevent captured ants from escaping. We hope that this newly developed trap would contribute to the prevention of invasive ants.
Despite the importance of behavioral ecotoxicological tests, few researches have been conducted to assess the quality of freshwater using behavior of test species, in part due to lack of standardized test method for quantifying the response. In this study, we developed a new test methods using non-biting midge larva’s burrowing behavior to assess field water quality and a new index, AUC (area under curve), to compare burrowing behavior quantitatively. Four kinds of field samples (residential, natural, agricultural and industrial areas) were tested using the method to validate our methodology and index. There were not significant differences in 96 h mortality and heavy metal concentration between samples, but AUC from the industry sample was significantly decreased.
Thc climate change has the potential to significantly modify the actual distribution of insect pest with unknown consequences on agricultural systems and management strategies. In this study, Thrips palmi Karny was selected to predict distribution under climate change. T. palmi was introduced and first recorded in 1993 in Korea, and has become a serious pest of vegetable and ornamental crops. The MaxEnt was applied to T. palmi to predict its potential geographic distribution in Korea and Japan under the RCP 8.5 climate changing scenario. The MaxEnt software package is one of the most popular tools for species distribution and environmental niche modeling. The habitat prediction model of T. palmi in Korea was validated by the distribution of T. palmi in Japan. Based on the MaxEnt modeling, T. palmi would expand their potential distribution to whole Korean peninsula except the alpine region in Gangwon-do and Yanggang-do and Hamgyeongbuk-do in 2070s. Therefore, the monitoring system and management strategy for T. palmi should be reconsidered and re-evaluated.
Insects reflect climate change dramatically because insects are poikilotherm and have huge biodiversity. Also, the prediction of insect distribution is very significant due to the position of this group giving diverse ecological services including their extraordinary economic importance. Accurate modeling of geographic distributions of insect species is crucial to various applications in ecology and conservation. The best performing techniques often require some parameter tuning, which may be prohibitively time-consuming to do separately for each species, or unreliable for small or biased data sets. The purpose of this study is to introduce and compare several models to predict insect distribution under climate change in Korea. This work would be helpful to researchers or decision makers by giving practical advice, for example, kinds of input/output data, applicability to GIS, to select appropriate model to predict insect distribution.
The use of aquatic species in ecotoxicity research is well established in developed countries. However there are limitations of using the species that are not native to Korea, and the toxicity data produced by domestic test species are significantly needed to reflect the domestic situation. In this study, the applicability of 3 kinds of native species, Chironomus yoshimatsui Martin et Sublette, Ephemera orientalis McLachlan and Heterocypris incongruens Ramdohr, as aquatic toxicity test species was studied. Also, the integration method of each species response to various industrial effluent and surface water was developed. In ecotoxicological researches using macro invertebrates, temperature is one of the most important toxicity-modifying factors, and temperature effect is species specific. Besides temperature effect, there are other physico-chemical factors that can affect test organisms, such as pH, water hardness and dissolved organic matter. The ideal test species for freshwater quality assessment is very sensitive to various pollutant but resistant to wide ranges of physico-chemical properties of environmental media. Behaviour is the cumulative interaction of a variety of biotic and abiotic factors that represents the animal′s response to internal and external factors and relates one organism to another. So, it is a major mechanism by which animals adapt to changes in their environment, including exposure to contaminants. Despite the importance of behavioral ecotoxicological test, there are few researches to assess the quality of freshwater and its sediment, in part due to the difficulties to obtain detailed quantitative data. This study shows the potentiality of behavioral test for water quality assessment using burrowing behavior of midge species exposed to several heavy metals. Finally, we propose a method which integrates each test into one concise and useful index and can be applied to various field water.
Proteomics may help to detect subtle pollution-related changes, such as responses to mixture pollution at low concentrations, where clear signs of toxicity are absent. Also proteomics provide potential in the discovery of new sensitive biomarkers for environmental pollution. We utilized SELDI-TOF MS (surface enhanced laser desorption. / ionization time-of-flight mass spectrometry) to analyze the proteomic profile of Heterocypris incongruens exposed to several heavy metals (lead, mercury, copper, cadmium and chromium) and pesticides (emamectin benzoate, endosulfan, cypermethrin, mancozeb and paraquat dichloride). Several highly significant biomarkers were selected to make a model of classification analysis. data sets obtained from H. incongruens exposed to pollutants were investigated for differential protein expression by SELDI-TOF MS and decision tree classification. Decision tree model was developed with training set, and then validated with test set from profiling data of H. incongruens. Machine learning techniques provide a promising approach to process the information from mass spectrometry data. Even thought the identification of protein would be ideal, class discrimination does not need it. In the future, this decision tree model would be validated with various levels of pollutants to apply field samples.
This study was conducted to examine the potential of surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) to screen Tetranychus urticae resistance to pyridaben and dicofol. T. urticae is one of the most important pests in greenhouse and orchard, and huge expense is needed to control because of its strong resistance to acaricides. Consequently speedy and accurate monitoring of acaricidal resistance is the key factor of IPM for T. urticae. SELDI-TOF MS is a novel approach to biomarker discovery that combines two powerful techniques: chromatography and mass spectrometry. It can provide a rapid protein expression profile of acaricidal sensitive and resistant T. urticae. In this study we had different protein and peptide patterns between sensitive and resistant strains to pyridaben and dicofol. In the future this results could be a useful data to develop a good monitoring tool of site and host specific mite resistance to various acaricides.
Biological control of greenhouse whitefly, Trialeurodes vaporariorum in greenhouse tomatoes with the parasitoid Encarsia formosa has been evaluated in Korea. However implementation of biological control program is retarded due to the reasons that lacks of site specific strategies. Aims of the present research are: (1) To develop an effective biological control method of the whitefly in tomato plants; the following were studied: (a) development of proper introduction rate of parasitoid, E. formosa, for the control of whiteflies, and (b) development of the effective control method of American serpentine leafminers with a parasitoid, Diglyphus isaea. (2) To build a computer-simulation model in which all factors are incorporated which have been studied in the relationship between whitefly and the parasitoid. The computer-simulation models would be used to estimate the effect of future developments in the greenhouse industry on the biological control of the greenhouse whitefly using E. formosa. More general goals are to develop reliable evaluation techniques to test the pest-control ability of natural enemies prior to their use in practical situations and to determine which role simulation models may play in estimating the results of biological control in new situations.
Myzus persicae, Heliothis assulta and Frankliniella occidentalis are the most severe pests of pepper in Korea. IPCC (Intergovernmental Panel on Climate Change) reported that the temperature would increase 7℃ at the end of this century. According to the elevated temperature, the pest population will be grow dramatically. We need to predict the pest-population size to maintain good crop productivity. DYMEX and CLIMEX are commercial software developed by CSIRO in Australia, to build and simulate population dynamics models. Using this software, we predicted population dynamics of M. persicae, H. assulta and F. occidentalis applying past climate data (1970) and future climate data (2070) which were generated by National Institute of Meteorological Research (NIMR). The population growth rates of M. persicae, H. assulta and F. occidentalis were 6300, 16 and 950 times, respectively, with 5 degree elevation. Therefore pest management should be conducted intensively in the future.
Myzus persicae, Heliothis assulta and Frankliniella occidentalis are major pepper pests in Korea. The objective of this study was to assess the pepper-yield decrease caused by population change of M. persicae, H. assulta and F. occidentalis. with temperature elevation. It is easy to expect that climate change will increase crop damage caused by pests. Therefore we should predict pest-population dynamics exactly and find the best available strategy for the pest management. Based on the many reported results of temperature development of the three kinds of pest, we simulated the future population dynamics using the computer softwater, DYMEX, developed by CSIRO. The results were that the population sizes and outbreak frequency of 3 kinds pest would increase with global warming. This work may be helpful to establish an effective pest management.
Heliothis assulta is the most severe pest of pepper in Korea. The management of this pest is very difficult because the larva live in the pepper fruit and emerge continuously. There are relatively abundant studies about temperature development of H. assulta, but few works are available to describe its future population dynamics which is caused by global warming. If we predict the long-term-population dynamics we can manage the H. assulta more effectively. Therefore we simulated the population size using the computer softwater, DYMEX, developed by CSIRO in Australia. Especially, we predicted population dynamics of H. assulta applying past climate data (1965-1985) and future climate data (2065-2085) which were generated by National Institute of Meteorological Research (NIMR). Comparing to past population dynamics, the epidemic size and frequency would increase in the future. This means that the population management of H. assulta should be conducted more sophisticatedly.
Acetaminophen (CAS 103-90-2) is one of the most used pharmaceuticals around the world. In Korea, it was produced 1,069 tons in 2003. This chemical is not eliminated in wastewater treatment plant and may flow into the ecosystem through various routes. Therefore, there is a possibility that it can make an adverse effect on aquatic organisms. To examine its ecological toxicity, we used three native Korean aquatic invertebrate species, Daphnia sp., Chironomus yoshimatsui, and Ephemera orientalis. The acute toxicity on Daphnia sp. was moderately high, and its 48 hour median immobilization concentration (EC50-immobilization) was 51.7 mg/L. On the other side, the reproductive toxicity was very high, and its EC50 of 25 day reproduction test was 0.005 mg/L. In E. orientalis egg hatching test, the median egg hatching inhibition concentration was 0.199 mg/L. C. yoshimatsui was most tolerant to acetaminophen, in which 48 hour median lethal concentration (LC50) was 400.0 mg/L and 45 day median emergence inhibition concentration (EC50-emergence) was 45.27 mg/L. From this results, we concluded that acetaminophen is hazardous to freshwater macroinvertebrates, especially to water flea. Therefore we need to study more about pharmaceuticals' ecotoxicology including acetaminophen and to assess their potential ecological risk.
Traditionally oxygen demands and concentrations of variable pollutant have been used for the assessment of lentic or lotic water quality. But there is a high probability that newly synthesized chemicals flow into the aquatic ecosystem, and it is very hard to investigate that many kinds of chemicals interact even though they exit at lower level than legal standards. As a consequence of limitation of chemical assessment for media, biological assessment techniques for accepters which are affected by pollutants or physicochemical properties have been developed. However, it still has several weak points because it does not have the ecological relevances using the internationally standard test species which do not inhabit Korea. Besides, the assessment using just one or two species may have a possibility of overestimation or underestimation because a certain species can be extremely sensitive or insensitive to a certain chemical or physicochemical property. Therefore, we used four kinds of indigenous aquatic invertebrates to assess the local stream quality and integrated their responses into a new index which ranges from 0(bad) to 1(good). We assessed four streams throughout Ansan and one stream in Gapyeong, and index values of two streams near residential and industrial area in Ansan were under 0.9 and the others were over 0.9.