The Azuki bean weevil, Callosobruchus chinensis L., is a common insect pest of stored products in the world. Radio-frequencydependent oviposition, development and adult performances of C. chinensis were examined at five radio-frequencies of0 (control), 5, 10, 20, and 30 kHz on azuki bean, cowpea, and mung bean seeds. The effects were studied on two successivegenerations of C. chinensis. The results showed that radio-frequency application have significant effects on the life variablesof C. chinensis. Radio-frequency exposures on three seed species not only impacted on developmental time, adult longevityand adult weight but negative effects were also transmitted to the successive generations. Longer developmental time andthe least adults of C. chinensis were emerged with shorter longevity in case of radio-frequency treatment than untreated.Decreasing the radio-frequency level further reduced the adult longevity and increased time for development of adults.The least adult emergence and short longevity was recorded for 5 kHz treatment. Radio-frequency treatments have alsoaffected on the adult performance such as weight of adult. The life variables of C. chinensis are discussed in terms oftargeting susceptibilities to radio-frequencies in storage as an alternative to chemical treatments.

Callosobruchus chinensis (Coleoptera: Bruchidae) is a cosmopolitan pest of stored grain legumes. This study assessed the effects of short-term exposure to low-temperatures (4, 0, and -4℃) and seven durations of storage (1, 5, 10, 15, 20, 25, and 30 days) on the survival, development, and adult performance of C. chinensis in laboratory. The effects were studied on three life stages (egg, larva [2-3 instar], and pupa) of C. chinensis. The results showed that low-temperature have significant effects on the life variables of C. chinensis. Among the stages, egg and pupa stages were most sensitive to low-temperature. The very low survival rates of eggs and no pupa survived at –4℃ after 10 days storage. Cold exposure at -4℃ not only increased egg and pupa mortality, but the negative effects also transmitted to the larvae and pupa developed from these eggs. Increasing the duration of cold exposure further reduced survival rates. Low-temperature treatments have also affected on the adult performances such as adult weight. However, there were not any negative effects of low-temperatures on the seed germination. The life variables of C. chinensis are discussed in terms of targeting particular susceptibilities to low-temperatures in different storage duration as an alternative to chemical treatments.

Increasing Lepidopteran pests such as Helicoverpa armigera are emerging pests of corn in Korea. They cause huge yield losses and deteriorate the quality of corn crop. We monitored the four major lepidopteran pests in major highland corn growing areas of Korea by employing sex pheromone trap during 2012 to 2015 for understanding those population dynamics. Among these species, H. armigera was found to be the main pest based on the damage intensity (80 ~ 90% of total damage). Some effective insecticides were selected such as Indoxacarb etc. Optimal timing of spraying was estimated at around 70 days after planting (earing season) to control H. armigera. Additional, two species of parasitoids (Therion circumflexum and Ophioninae sp.) was identified from H. armigera. However, more extensive survey for natural enemies is needed to set the natural enemy based control program.

Among several insect pests in the potato fields, Liriomyza huidobrensis, pea leafminer, is emerging as a new threat to potato plants. Adult females damage the host mesophyll cells host due to ovipositor probing. After egg hatching, the eclosing larva also damage the leaf by mining the mesophyll and causing tissue death. Despite the importance of leafminer in potato production, there is no information available regarding its resistance level to potato cultivars in Korea. Using choice test, 21 potato cultivars consisting of 11 early-maturing, 6 mid-maturing and 4 late-maturing cultivars were evaluated the resistance to pea leafminer in the greenhouse and field condition. In this test, significant differences for resistance were observed. High levels of resistance to leafminers were obtained from cvs. Namsuh, Seohong, Jayoung and Superior. These resistant cultivars might be useful in future breeding programmes.

The azuki bean weevil, Callosobruchus chinensis L., which is one of the notorious stored grain insect pest. Temperature-dependent development of C. chinensis. was examined at six temperatures of 14, 18, 22, 26, 30, and 34℃ on azuki bean and cowpea seeds. The total developmental time (egg to adult) decreased with increasing temperature from 14 to 34℃ on both seeds. However, total developmental time varied from 127.9 and 125.9 days at 14℃ to 19.9 and 20.3 days at 34℃ on azuki bean and cowpea seeds, respectively. The lower temperature thresholds (Tmin) were estimated to be 9.52℃ and 10.36℃, and the thermal constants (K) were 526.31 DD and 454.54 DD, on azuki bean and cowpea using general linear model, respectively, and the lower temperature thresholds and the thermal constants estimated by Ikemoto-Takai linear models were 10.63℃ and 10.79℃, and were 466.18 DD and 436.28 DD, on azuki bean and cowpea, respectively. These findings on thermal requirements and temperature thresholds can be used to predict the occurrence, number of generations and population dynamics of C. chinensis.

The development of resistant seeds to manage this pest is a big challenge for breeders. We investigated the oviposition preference and development of C. chinensis on two susceptible mungbean cultivars (Seonwha and Gyeongseon) and one previously reported resistant cultivar Jangan, compared to the susceptible cowpea, Yeonbun, by offering a multiple choice test and a no-choice test. Additional, insect stage wise development of C. chinensis was also examined at four temperatures (20, 25, 30 and 35℃). The both choice tests results showed that the cowpea is the most suitable seed host for oviposition. Total developmental time from egg to adult stage ranged from 27.01 to 38.2 days, and developmental time was shortest on the cowpea and longest on Jangan mungbean. However, no successful development of C. chinensis on Jangan mungbean occurred at all constant temperatures. Higher rate of adult emergence and longer adult longevity were found on cowpea and mungbean except Jangan mungbean. Results suggest, higher performance of C. chinensis on cowpea and mungbean might be governed by physical as well as chemical attributes of the seeds. Thus, Jangan mungbean could be stand as a resistant one against bruchids and it could be a resistant sources for successful breeding.

The pea leafminer fly, Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae), is an emerging pest in Korea. High population and heavy damage of this pest were observed from potato fields in the southern part of Korea in 2012. Morphological and genetic evidence confirmed the species as L. huidobrensis. The infestation was expanding throughout the country and a rich complex of parasitoid was recognized. From the exclusion study, high density infestation of leafminers reduced yield among potato varieties (Chubeak, Seohong, Goun, Dejima, and Sumi). Higher leaf damage was evident in the lower part of plants. In olfactory bioassay and feeding preference tests, leafminers choosed the Goun variety most. Given the six constant temperatures, the developmental time from egg to adult significantly decreased with increment of temperatures. From the insecticide toxicity tests, abamectin and lepimectin and spinetoram were found effective against immature stages, while cartap hydrochlorid (Neonicotinoid) was against adult insects. Overall, these studies help to pave the ways for managing this new invasive pest.

The striped fleas beetle (SFB), Phyllotreta striolata is a notorious and widely distributed pest in the world including Korea. We surveyed SFB insecticide resistance in Pyeongchang and Hoengseng population. Leaf dipping bioassay with recommended concentration of insecticides was performed using SFB adults. Two populations showed high level of resistance in various insecticides particularly neonicotinoids. Nicotinic acetylcholinesterase receptor (nAChR) is well known target site in neonicotinoid. Therefore, we tried to identify the nAChR from the SFB. Primary, partial contig sequence obtained by RNAseq from Hoengseng population and additional gap fillings were conducted. Total 12 nAChR subunits (10 alpha subunits and 2 beta subunits) were identified and phylogenetic relationships were predicted. Earlier studies reported that point mutations contribute to develop the imidacloprid resistance in aphids and brown planthopper, however we did not find it. Further studies relative to neonicotinoid insecticide resistance mechanism are demanded.

Liriomyza leafminer flies comprise a pest group that causes both considerable economic losses and serious quarantine problems. To investigate Liriomyza spp. abundance and distribution along with natural enemies, we surveyed of leafminer (LM) species and its natural enemies (NE) on potato crop from 146 farmers’ field in the potato growing provinces during 2015. Sweeping (10 sweeps/ field) and visual inspection were employed within 5 minute-walking distance, and damaged leaflets (10 leaflets/ field) were collected in each field. Leafminer species were identified by morphological, and its NE was identified by morphological and molecular techniques. L. huidobrensis was the most dominant Liriomyza species. Distribution of L. huidobrensis on potato fields was expanding. Highest potato fields were infested with leafminer in southern parts of country. Highest rate (100%) field damage was recorded in Miryang, Namwon, Henam, and Boseong. Overall, NE species collected constituted of 4 families and 18 and 20 species in sweeping, and damaged samples respectively. There was a rich complex of parasitoid species including 20 species (13 species of Eulophidae family). The endoparasitoid, Braconid sp., Ganaspidium sp., and ectoparasitoid, Diglyphus isaea were dominant species in sweeping. While Diglyphus isaea, Hemiptarsenus varicornis, and the Braconid sp. were most dominant species collected from damaged samples. The number and diversity of parasitoid species in potato crop in Korea provides insight into the development of integrated control strategies of invasive LM pests in the field, and glasshouse crops.

The habitat of the cockroach varies relative to species. The German cockroach (Blattella germanica) lives in human dwelling while B. nipponica lives in mountainous region. Even though, these two species have similar morphology, their habitats and walking speed were different. Underlying this fact, we hypothesized that habitats might influence on the walking speed via altering particularly nervous system including acetylcholinesterase (EC3.1.1.7, AChE). Full length ORFs were cloned from each species and sequenced. Sequence analyses showed that both genes in each species possess typical features of ace, and that Bgace1 and Bnace1. Those features are orthologous to the insect ace1 whereas Bgace2 and Bnace2 are to the insect ace2. Some SNPs were observed but Bgace1 and 2 showed high similarity (99%) with Bgace1 and 2, respectively. Multiple AChE bands were identified by native PAGE and IEF from three tissues (head, leg and other body) and their expression pattern was almost identical between two species. However, Esterase expression patterns were significantly different. Furthermore, length as well as detailed structure of antenna, leg and tail cerci was also significantly different. Taken together, various factors such as sensory organ detailed morphology and esterases are responsible for habitat and walking speed difference.

A new gregarine species (Eugregarinida: Gregarinidae) was previously reported from daikon leaf beetle, Phaedon brassicae at Daegwallyeong in Korea. Here, we found another novel gregarine species from the striped flea beetle, Phyllotreta striolata (Coleoptera: Chrysomelidae). This paper describes the morphological and molecular-biological characteristics of Gregarine species associated to P. brassicae and P. striolata. The size and body shape at mature trophozoite stage were the main diagnostic characteristics of those species. Gregarines from P. brassicae were bigger size (100um) with square shaped body while Gregarines from P. striolata were slightly smaller size (80um) with egg shaped body. Based on the partial 18S rDNA sequence, gregarine species from P. striolata was grouped in eugregarine and also this new gregarine showed 85% homology that of the reported Gregarina sp. from P. brassicae. However, gut dissection result showed that each species had own gregarine parasite species association. These results were identical in local populations from three surveyed locations. There was positive relationship between infection rates and elevation for gregarine related to P. striolata. Therefore, we suggested that the gregarines and their coleopteran hosts have species-specific interaction via co-evolution.

The pea leafminer fly, Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae), is a polyphagous pest attacking wide range of field and greenhouse crops and ornamental plants. Surprisingly, localized outbreaks with high population and heavy unique damage of leafminers were observed from the field survey of potato fields in the southern parts (Miryand and Goryeong) of Korea in 2012. L. huidobrensis was the responsible for those potato damages based on the morphological and genetic characteristics. Then after, it added a one more emerging species in Korean Liriomyza account. Infestation of L. huidobrensis was expanding and reported in major potato growing areas of the country. Genetic evidence showed the close relationship with Chinese L. huidobrensis population, so it might be invaded from China. As a new emerging pest, very few informations relative to this pest are available in Korean prospective. There is also significant potential for it to widen its distribution, as the Korean Peninsula is a hot spot of climate change, particularly global warming. There are a lot of challenges uprooting infront of researchers and growers. It is demanded to explore new secrets and to be ready to tackle of this invasive pest, L. huidobrensis.

The development of Liriomyza huidobrensis (Blanchard), an economic pest of wide range of field crops and ornamental plants, was studied under laboratory conditions at six constant temperatures (10, 15, 20, 25, 27 and 30oC). The total development period decreased with increasing temperatures between 15 and 27oC. In 10oC, eggs did not hatch and in 30oC, pupa did not survive. So, it may be assumed that these temperatures fall outside the development. Linear regression was used to describe the relationship between development rate and temperature. For total immature development (egg to adult) required 250 degree-days (DD) above the threshold of 9.75oC. The developmental data were fitted to a nonlinear temperature-dependent model (Lactin-1) for best described of development. Development rates of males and females did not differ in 20 and 25oC. High immature mortality was recorded in 27oC. Sex ratio of the surviving individuals was 0.62 from this study. Thermal requirements and temperature thresholds can be used to forecast the occurrence, number of generations and population dynamics of L. huidobrensis.

Liriomyza leafminer flies comprise a pest group that causes both considerable economic losses and serious quarantine problems. We reported for the first time of the infestation of field crops by this invasive leafminer L. huidobrensis in Korea in 2012. Distribution survey of leafminer flies and other insect pests on potato crops along with associated natural enemies was conducted from 378 farmers' field in most of the potato growing provinces during 2011, 2012 and 2013. Sweeping (10 sweeps/field) and visual inspection were employed within 5 minute-walking distance each field. For damage rate was also calculated for each field. Ten mined leaflets were investigated for parasitoid species identification. Leafminer flies were identified by morphologically and molecular. However, parasitoid species were only morphologically identified. All the leafminer flies collected were identified as L. huidobrensis. No leafminer flies infested fields were recorded in Boseong (Jeollanam-do) in 2011. L. huidobrensis infested fields with unique crop damage symptoms were found only in Miryang and Goryeong (Gyeongsangnam-do) in 2012. There was significant different in leafminer infested fields among the surveyed locations in 2012 (f=85.73, df=5, 127, P<0.0001). Higher damaged (100%) potato fields were recorded in Miryang. Similarly, the leafminer infested potato fields were significantly different among the surveyed locations in 2013 (f=36.77, df=19, 201, P<0.0001). Highest damaged rates (100%) were recorded in all the surveyed locations of Gyeongsangnam-do. Increasing distribution expansion pattern of L. huidobrensis was found. Distribution covers from southern parts to northern parts of the country. The study on rate of distribution and factors responsible in rapid distribution of L. huidobrensis in Korea are demanded.

Liriomyza species are the major pests of greenhouse and field crops. It was as minor pests in past, but the pest population increased rapidly such as L. trifolii, L. huidobresnsis and L. sativae during recent years is attributed to application of ineffective insecticides and developed insecticide resistance. This study was carried out to determine the efficacy of insecticides groups, Anthranilic diamide, Biopesticide, Carbamate, Neonicotinoid, Organophosphate, Pyrethroid and Oxadiazine, recommended for the control of leafminer species in Korea. Bioassay tests were done on first, third larval stages and adults under glasshouse and laboratory conditions respectively. The result showed significant differences in toxicity among the tested insecticides. The mortality of abamectin and lepimectin and spinosad were higher (>50%) in larvae stages. Etofenprox insecticide was not effective on larvae stage. The toxicity of Cartap hydrochlorid (Neonicotinoid) was higher (100%) in adult insects, followed by thiamethoxam, etofenprox and indoxacarb. Abamectin and lepimectin showed the decreasing toxicity level as insect stage developed. Abamectin showed least toxicity (26.67%) in adult stage. Spinetoram and emamectin benzoate showed higher toxicity (>50%) in all the insect stages tested. It could be suggested that abmectin and lepimectin have high efficiencies on control of larvae. However, spinosad and emamectin benzoate has higher potential on the control of both larvae and adult insects.

The potato leafminer fly, Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae) is a polyphagous pest attacking many vegetables and ornamental plants. We found L. huidobrensis were infesting potato crop in Miryang and Goreyong in 2011. Five potato (Solanum tuberosum) varieties (Ghowun, Daeri, Sumi, Chubeak, and Seohong) were tested for the preference of L. huidobrensis. In the olfactormeter bioassay, leafminers chose the Ghowun variety most (55%) followed by Sumi (18%). Remaining 3 varieties were chosen less than 10%. When leafminers choose and move toward the preferred variety, movement speed was faster. In the plant choice test in the laboratory, as expected, Ghowon was the most chosen but the choice of the other 4 varieties was not different. The same pattern as found in the plant choice test conducted in the greenhouse. Feeding frequency was the highest in Ghowun variety followed by Sumi > Daeri = Seohong > Chubaek in the laboratory test but Ghowun > Sumi > Chubaek > Daeri = Seohong in greenhouse test. When measured in 2 weeks after release, plant damage rates and number of mines were in congruence to the preference results. Further study is needed to clarity the factor responsible for the choice of the plants and also the ways to manage this new pest.

Liriomyza leafminers comprise a pest group that causes both considerable economic losses and serious quarantine problems. In recent years, the pest status of Liriomyza sp. has changed in Korea, as well as other areas of the world. Potato field survey was conducted in 157 farmers’ field from five provinces during 2011 and 2012. Foliar insect monitoring was done within 5 minutes walking distance by visual inspection. Leafminer fly and parasitoids were collected by sweeping net (10 sweeps/field) in same field in each time. Overall, potato insect species collected constituted of 7 orders, 22 families and 42 species. Aphis gossypii was most abundant species in all the locations. However, Potato tuber moth, Pthorimaea operculella was only dominated species in Boesong (Jellanam-do). L. huidobrensis was the first record infesting the potato in Korea. Liriomyza huidobrensis was only found from Miryang (Gyeongsangnam-do) and Goreyong (Gyeongsangbuk-do). There is a rich complex of parasitoid species; 18 species of parasitoids were recorded. Most parasitoid species (11) belong to the Eulophidae family. The most abundant species were the ectoparasitoid, Diglyphus isaea and endoparasitoid, Ganaspidiumsp. The number and diversity of parasitoid species in potato crop in Korea provides insight into the development of integrated management strategies of leafminer pests.

Mungbean is an important crop in Nepal. Heteropteran bugs, Nezara virudula, Dolycoris baccurum, and Melanacanthus scutellaris are significantly influencing qualitative and quantitative loss in soybean and mungbean. Though pesticide application is common practice for management of these bugs, pesticide avoidance by the bugs stalls proper management. As an alternative, trap cropping with variety mostly preferred by the bugs as trap crops along with the main crop is considered. Selection of most preferred mungbean variety was performed with six (VC 6173 A; VC 6153 B-20G; VC 3960 A-88; Kalyan; Pratikchha; Saptari local) relative to Saptari local variety. Significant difference was recorded in number of bugs occurrence among the six varieties with maximum number of bugs in VC 6173 (3 bugs/plant) which showed lowest yield. For application, three different trap crop designs were employed in the field. There was significant difference between the main crop i.e. variety Pratiksha and the variety VC6173A used as trap crop in two designs. In conclusion VC6173A is a probable trap crop and the two designs can be employed in the field.