• Korean journal of applied entomology
• /
• v.61 no.1
• /
• pp.51-62
• /
• 2022

Numerous insect pests threaten the Korean orchard industry through feeding on various tissues of fruit trees. Generally, the control of economically important orchard pests is based on the use of chemical insecticides. Owing to growing concerns regarding the environmental and human health effects of insecticides, environment-friendly pest control strategies are urgently needed. Pheromones of orchard pests could lead to an environmentally safe control system based on mating disruption or mass trapping. This review summarizes the functions and compounds of known pheromones from 51 orchard pests in Korea. The pheromones identified to date from 14 species in the families Miridae, Aphididae, Diaspididae, Pseudococcidae, Rutelidae, Cecidomyiidae, and Eurytomidae and 26 species in the order Lepidoptera are female-produced sex pheromones that attract only males. In contrast, all known examples for 11 species in the families Alydidae, Pentatomidae, Thripidae and Cerambycidae are male-produced aggregation pheromones that attract both sexes. Research on pheromones in new pests, kairomones in key orchard pests, mating disruption dispensers to generate prolonged release of the pheromones, and trap design and trap location for mass trapping will be required for the expanded use of pheromones and other semiochemicals in orchard pest management in the future.

• Korean journal of applied entomology
• /
• v.54 no.2
• /
• pp.99-109
• /
• 2015

Insecticidal and antifeeding activities of 29 commercialized eco-friendly organic products for managing plant diseases and insect pests against Plutella xylostella larvae, Spodoptera exigua larvae, Frankliniella occidentalis adults, and Myzus persicae adults were tested using spraying and leaf dipping bioassays under laboratory conditions. Products containing 60% Sophora extract (EOIS) and mixtures (EOISm) with Sophora extract, Stemona japonica extract, Melia azedarach extract, and Nepeta cataria extract as well as mixtures (EOISc) with Sophora extract, Chenopodium ambrosioides extract, and Melia azedarach extract as active ingredients showed strong insecticidal activity at recommended concentration against P. xylostella larvae. At half concentration, their insecticidal activities were decreased under 50%. The EOIS gave good insecticidal activity against S. exigua larvae and also showed 85% and 95% insecticidal activity at 24 and 48 hours after treatment to F. occidentalis adults, respectively. For M. persicae adults, EOISm and mixtures (EOIR) containing rape seed extract, neem extract, and castar oil produced 93% and 68% insecticidal activity, but their activities did not be increased at double concentration. EOISm only showed 100% contact toxicity against M. persicae adults exposed to dipping leaves. Interestingly, the insecticidal activity of EOIR and EOICi (citronella oil and derris extract) against M. persicae adults was increased with exposed time and concentration. In addition, EOICe (cedar oil), EOIS, EOISm, EOISc, EOIM (microorganism), EOIR, EOIPe (plant extract), and EOIT (tea tree extract) gave strong antifeeding activity against S. exigua and P. xylostella larvae. EOIB, EOIBs, EOIM, EOICi, and EOIMc showed above 70% antifeeding activity to the lepidopteran larvae. These results indicate that mixtures containing 2 to 3 plant extracts with Sophora extract show good activities against insect pests, although the difference of insecticidal and antifeeding activities was produced depending on both a tested insect species and an active ingredient or concentration.

• Korean Journal of Environmental Biology
• /
• v.25 no.4
• /
• pp.326-335
• /
• 2007

This study was conducted to assess the environmental risks of anthracnose resistant transgenic chili peppers with the PepEST gene on non-target organisms in the agroecosystem environments during the chili pepper growing seasons in 2006. We quantitatively collected arthropods assemblages living on leaves and flowers of chili peppers on June 20, July 25, and August 25 by using an insect vacuum collector to compare the patterns of arthropod community structures between non-transgenic chili peppers (nTR, WT512) and anthracnose resistant transgenic chili peppers (TR, line 68). We found the seasonal difference with the highest species richness and Shannon's diversity in July's sampling among the growing seasons (P<0.05) and each sampling season showed the different arthropod community composition. We also found there was no statistical difference between the two types of crops, nTR and TR, at each sampling time (P>0.05). The significance level of arthropod community showed that there were lots of seasonal difference of functional groups as well as taxa but only the herbivore group in the functional groups was significantly different for the types of plants (P<0.05). So, we further examined the herbivore groups to find any potential damage and identified the possibility of herbivorous damage from some herbivores, grasshoppers, aphids and thrips. Although we couldn't find any adverse effects from the environmental risk assessment between the arthropod community structures on two types of plants from our results, we should keep working for the environmental risk assessment because of the herbivorous potential risk possibility.

• Korean journal of applied entomology
• /
• v.48 no.1
• /
• pp.87-94
• /
• 2009

KNI3126 which is the eco-friendly material made by plant extracts - neem and matrine - have been evaluated for efficacies against 6 main pests and toxicity on natural enemies. Insecticidal efficacies of KNI3126 against plant hopper were above 95% at 5 days after treatment (DAT), whereas pesticidal effects against the cotton aphid were above 95% at 3 DAT and slightly decreased at 5 DAT. Insecticidal efficacy against the palm thrips resulted in lower control value as 68.1% than that of chemical insecticides. KNI3126 showed more than 95% control value against diamond back moth, suggesting that it could suppress the population of pest hard to control as eco-friendly material. Mortalities against two-spotted spider mite were about 80% at 1 DAT and over 90% at 5 DAT, respectively. For evaluation of the toxicity on natural enemies, effect against predatory natural enemy was classified as moderate selective toxicity based on the criterion of International Organization of Bio-Control (IOBC), whereas against parasitic natural enemies was found to be relatively safe. Repellent effect was weak against plant hopper, but strong against two-spotted spider mite. In the toxicity test for safety, KNI3126 was classified as the lowest level at acute oral, acute dermal and fish toxicity test and did not induce the irritancy at skin irritation test and eye irritation test.

• Korean journal of applied entomology
• /
• v.59 no.1
• /
• pp.55-64
• /
• 2020

Smart greenhouses are primarily used for growing fruits and vegetables, such as sweet peppers, tomatoes, strawberries. Although the number of smart greenhouses has been increasing exponentially, no studies have been performed to evaluate the state of smart greenhouses in Korea. Therefore, this study was conducted to determine current state of smart greenhouses with regard to greenhouse specifications, crop growing methods, pests, and user satisfaction in Korea. Contact information for smart greenhouses was provided by the officials of local agricultural research and extension services. This survey was conducted by visiting each greenhouse. Results showed that approximately 50% of surveyed smart greenhouses were between 3,300 ㎡ and 6,600 ㎡. The most frequently chosen method for pest control was chemical pesticides (97.1%). Powdery mildew and gray mold comprised 54.4% and 33.8% of the crop diseases, respectively. All tomato greenhouse farmers considered whiteflies the most problematic pest. In contrast, 76.5% and 70.6% of sweet pepper farmers believed thrips and aphids posed significant threats, respectively. The mean satisfaction score was 7.5 out of 10 points, with 10 being "extremely satisfied". These results will aid in decision making with respect to the management of current smart greenhouses and the design of future smart farms in Korea.

• Korean journal of applied entomology
• /
• v.48 no.4
• /
• pp.503-508
• /
• 2009

Biological-control-based-integrated-pest-management of major pests occurring on sweet pepper in greenhouse during summer season was tried. As many as 2.1 Orius laevigatus per $m^2$ were released in two times on June 6 and 19, and the population of thrips was kept under control and accordingly the damage was negligible throughout the season. To control aphids, a total of 0.8 Aphidius colemani per $m^2$ were released in four times, 0.2 of them at a time, flonicamid on May 14 and July 18 and pymetrozine on June 14 and September 4 were sprayed on the spots of high aphid occurrence to reduce the release of the wasp, and the density of aphids was kept under control. Whitefly was controlled successfully by releasing a total of 343.4 Amblyseius swirski per $m^2$ in nine times, 38.1 of them at a time, from May 9 until November 12 and dinotefuran was sprayed on November 12 when the density of whitefly increased up to 200 per trap. Tetranichus kanzawai was controlled by both Phytoseiulus persimilis which was released a total of 44.4 per $m^2$ in five times 8.9 of them at a time from May 23 to September 10, and the A. swirski which was released for the control of whitefly.

• Korean Journal of Organic Agriculture
• /
• v.21 no.4
• /
• pp.601-615
• /
• 2013

This study was conducted to compare the community structure and biodiversity of arthropods between conventional and organic red pepper fields. A total of 36 species of 24 families belonging to 10 orders from collected 28,718 arthropods; 6,901 individuals from conventional field and 21,871 individuals from organic field. A number of species comprising arthropod community was same in both fields as 32 species. Species richness of Diptera was the highest in conventional field and that of Hymenoptera and Colembolla was the highest in organic field. Abundance of Frankliniella intonsa was the highest regardless of farming method. Helicoverpa assulta was dominant in conventional field, and Homidia mediaseta, Diptera sp. 4 and Pardosa astrigera were dominant in organic field. Diversity of community on the ground was higher in organic field and statistically different. Similarity of arthropod community showed difference with 34.07% on the ground and 26.95% in the plant above ground. In the ecologically functional guild: species richness of general, pest and parasitoid of natural enemy groups in the plant above ground were statistically different and pest and parasitoid groups were higher in organic field, abundance of predator group of natural enemy on the ground was 2 times higher in organic field and statistically different and diversity of general and parasitoid groups in the plant above ground were statistically different. In the relative occupancy rate, pest group was the highest in conventional field and decomposer group was the highest in organic field. The results of present study is considered to provide useful information of arthropod community for developing efficient insect pest management in organic farming.

• Korean journal of applied entomology
• /
• v.46 no.1 s.145
• /
• pp.63-69
• /
• 2007

This study was conducted to examine the problems that would arise in our cropping systems when introducing Gain Threshold (GT) which is an important element in determining Economic Injury Level (EIL). Cain Threshold (GT) can be defined as the amount of damage (=yield loss) to justify management, and calculated by dividing the management costs by the market crop price. GTs for some pests in rice, soybean, and greenhouse vegetable crops cultivation were estimated and also compared with those in foreign countries. GTs and percentage of yield loss equivalent to them were estimated to be 4.6-6.1kg/10a/season and 1.0-1.3% for brown planthopper, white-backed planthopper, rice water weevil, and sheath blight, whereas for rice blast in rice cultivation were 12.7kg/10a/season and 2.7%. In soybean cultivation, the values for bean bug were 6.2 kg/10a/season and 3.6%. GTs and percentage of yield loss estimated for melon thrips, whitefly, and downy mildew in cucumber cultivation were 10.0-12.6kg/10a/week, 1.4-1.7%, and the values for two spotted mite and gray mildew in strawberry cultivation were 3.1-3.5kg/10a/week, 1.3-1.5%, and the values for American leaf minor, whitefly, and gray mold in tomato were 8.4-9.7kg/10a/week, 1.7-1.9%. Overall GTs in our cropping systems were so low compared to those in foreign countries, which meant that the low GTs might yield the low EILs. Therefore, we could suggest that prior to direct introduction of GTs calculated from current cultivation systems in developing EILs it is necessary to seriously consider reasonable values of GTs or the yield loss equivalents to them.

• Horticultural Science & Technology
• /
• v.32 no.4
• /
• pp.517-524
• /
• 2014

As an assessment of substantial equivalence and environmental risks of branchless chrysanthemum GM lines (LeLS69, LeLS76, LeLS80) developed in Korea, we investigated their degree of branchlessness and developmental characteristics including growth and flowering, as well as the stability of populations of insect pests and soil microbes. The GM lines were compared with a control variety, 'Jinba'. LeLS80 showed the highest level of branchlessness among the three GM lines, whereas abnormal axillary buds developed in lines LeLS76 and LeLS69. There were no significant differences between the growth characteristics of 'Jinba' and the GM lines. The branchlessness LeLS80 was increased during the summer season, suggesting that it is a useful germplasm for developing elite branchless cultivars. These GM lines showed no significant differences in the occurrence of five insect pests including aphids, mites, leaf miners, thrips, and whiteflies. Similarly, for soil microbes including bacteria and actinomycetes, there were no significant differences between 'Jinba' and the GM lines. However, there was a higher occurrence of fungi in the GM lines compared to 'Jinba'. Our findings suggest that 'Jinba' and the GM lines are substantially equivalent, although further monitoring studies are needed to confirm this.