• Korean journal of applied entomology
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• v.61 no.3
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• pp.435-447
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• 2022

The soybean podborer, Matsumuraeses falcana (Lepidoptera: Tortricidae), is one of important pests in soybean crop. In the purpose of forecasting population dynamics of M. falcana, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of Matsumuraeses falcana at seven constant temperatures of 10, 13, 19, 22, 25, 28, and 31℃. Eggs hatched successfully at all temperature subjected. M. falcana developed from egg hatching to adult emergence at the tested temperatures except 10, 13, and 31℃. The developmental period of each life stage and adult longevity of M. falcana decreased as temperature increased. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. falcana were estimated by linear regression as 10.2℃ and 492.04DD, respectively. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. TL and TH from egg hatching to adult emergence using SSI model were 16.7℃ and 29.1℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. falcana was 12.4℃. We constructed the adult oviposition model of M. falcana using adult survivorship and fecundity. Temperature-dependent immature development and adult oviposition models will help constructing the population model of M. falcana and developing the strategies of integrated pest management in soybean fields.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.461-473
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• 2022

Matsumuraeses phaseoli is one of important pests in soybean crops, especially adzuki beans. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. phaseoli for understanding the biological characteristics of M. phaseoli at ten constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected except 7℃ and 34℃. The developmental period of each life stage and adult longevity of M. phaseoli decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. phaseoli were estimated by linear regression as 9.04℃ and 422.97DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 20.0℃ and 32.3℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. phaseoli was 12.3℃. We constructed the adult oviposition model of M. phaseoli using adult survivorship and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M. falcana and to establish the strategy of integrated pest management in soybean fields.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.481-496
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• 2022

In order to establish an effective pest control strategy, we investigated the occurrence of lepidopteran insects in the major trees growing in urban forests from 2019 to 2021. In total, we recorded 76 species of 14 families in Prunus spp., 40 species of eight families in Acer spp., 43 species of 10 families in Zelkova serrata, 28 species of seven families in Rhododendron spp., and 10 species of four families in Hibiscus syriacus. Among these, Hyphantria cunea and Lymantria dispar were recorded from all five tree taxa monitored. The most frequently occurring species in the different tree groups were as follows: H. cunea and Phalera flavescens in Prunus yedoensis, Epinotia ulmicola in Z. serrata, and Rehimena surusalis in H. syriacus. H. cunea also occurred in Rhododendron spp. and Acer spp., although the numbers were lower than those recorded in Prunus spp. and Z. serrata. Our results highlight the importance of focusing on the frequency of occurrence of lepidopteran insects in Prunus spp. and Z. serrata, whereas the presence of these insects in both Acer spp. and Rhododendron spp. Appears to be less problematic. From the perspective of reducing the risks to human health, our findings indicate that the application of pheromones for monitoring lepidopteran species and the use of mating disruptors would be desirable approaches that would contribute to minimizing the spraying of pesticides in urban forests.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.250-256
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• 2002

The objective was to know if chinese cabbage growers in Gangwon alpine farmland control agricultural pests including weeds effectively and use pesticide properly. Examiners visited 185 farmers at Taebaek, Pyongchang, and Jeongseon and surveyed 33 questions on pest control methods pesticide use. Chinese cabbage farmers have noxious plant diseases such as clubroot, bacterial soft rot, downy mildew, anthracnose, and mosaic disease, and also noxious insects such as diamondback moth, aphid, beet armyworm, common cabbage worm, and Japanese native slug. In addition, farmers have noxious weeds such as common chickweed, marsh pepper, hairy crabgrass, common purslane, and horseweed. To control diseases and insects, 51.3% of farmers used many chemical agents, while 20.7% of farmers used chemical agents with too much emphasis on paraquat and glyphosate to control weeds: 87.2% of the answered farmers have a preference of the both non-selective herbicides. Farmers in the survey area selected pesticides on the basis of their own experience and sales managers' recommendation (84.2%) which results in the use of inappropriate pesticides such diniconazole. Many farmers have experienced phytotoxicities (46.7%) and pesticide poisoning (51.2%). We conclude that a systematic educational program for the proper selection and use of pesticides should be conducted for chinese cabbage growers in Gangwon alpine farmland.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.284-292
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• 2012

To date, chemical control remains the most common way to reduce beet armyworm (Spodoptera exigua) populations. However, this insect has become more tolerant or resistant to many chemical insecticides and the insect larvae usually hide inside hollow, tube-like leaves of host plant so they were difficult to kill by spraying insecticides. The use of viral and bacterial insecticide to solve these problems has not been successful because of their novel feeding habit. To overcome these problems, in this study, the biological characteristics and virulence of an entomopathogenic fungus isolated from the cadaver of larvae beet armyworm were investigated. Isolated entomopathogenic fungus was identified as Nomeraea rileyi (Farlow) Samson by morphological examinations and genetic identification using sequences of the ITS, ${\beta}$-tubulin gene and EF1-${\alpha}$ regions. This fungus was named as N. rileyi SDSe. Virulence tests against 3rd larvae of beet armyworm were conducted with various conidial suspensions from $1{\times}10^4$ to $10^8$ conidia/ml of N. rileyi SDSe in laboratory conditions. Mortality rate of beet armyworm showed from 20 to 54% and the virulence increased with increasing conidial concentrations. Although N. rileyi SDSe showed low mortality rate against beet armyworm, it is expected that N. rileyi SDSe will be used effectively in the integrated pest management programs against the beet armyworm.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.279-288
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• 2011

To suggest the weed management technique for environment friendly rice cultivation, we investigated occurrence patterns of weeds, the actual condition of weed management, and rice yield at the environment friendly agricultural complex located in Honam and Chungnam regions. The practical performance of weed management was relatively satisfactory in decreasing order of agricultural technique with golden-apple-snail (GAS) > agricultural technique with duck (Duck) > agricultural technique with rice bran (RB) > agricultural technique with soft-shelled turtle (ST). In the rice fields employed by agricultural technique with GAS, the dominant weeds were Echinochloa crus-galli, Ludwigia prostrata, Monochoria vaginalis, Sagittaria trifolia, and Aneilema keisak. However, E. crus-galli, M. vaginalis, L. prostrata, Aeschynomene indica and Bidens frondosa were found as dominant weeds at the fields using the Duck and E. crus-galli, M. vaginalis, L. prostrata, Polyganum hydropiper and Eleocharis kuroguwai at the fields using RB. In comparison of rice yield ($5.2\;MT\;ha^{-1}$) obtained from the conventional cultivation using herbicides, about 93% was reached by Duck, about 91% by GAS, about 92% by RB, and about 78% by ST. When rice qualities obtained from environment friendly rice cultivation were compared with those from the conventional cultivation, the producing rates of perfect kernel, immature kernel, immature opaque kernel, cracked rice, and damaged kernel were lower in the former cultivation, whereas contents of protein, amylose, and fatty acid were similar in the two cultivation methods. The problems found in the environment friendly agriculture were poor plowing and harrowing, carless irrigation management, and geological poor condition as cultivation area with cold water. These have caused severe infestation of weeds, frequent incident of disease and insect pest, and rice lodging. This resulted in reduction of rice yield as high as about 32 to 79% as compared with the conventional cultivation using herbicides.

• Korean journal of applied entomology
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• v.54 no.3
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• pp.191-197
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• 2015

Fruit drop due to Eurytoma maslovskii infestations of Japanese apricot (Prunus mume) is a serious economic issue in most parts of Jeonnam Province, with the exception of the coastal areas such as Wando, Shinan, Yeosu, and Muan. The average incidence of fruit drop was 67% in 2013 and 33.3% in 2014. E. maslovskii larvae overwinter inside the pits of Japanese apricots. Larval survival rates decrease to less than 30% after a rainy summer season. The eggs are long oval of 0.68 mm, 0.29 mm and ivory white. Mature larva is of 6.56 mm, 3.18 mm. Free pupa are black, adult females and males of 6.97 mm, 4.90 mm lengths, respectively, while the ovipositor is 0.64 mm in length. Adult emergence occurs from early April to early May, when Japanese apricot fruits are from 4 mm to 17 mm in diameter. Adults persist for 13.5 d after emergence, and the sex ratio of females to males was found th be 45.9:54.1. Although up to four eggs may be oviposited per fruit, only one larva will ultimately survive, ans the larvae are cannibalistic. The period during which E. maslovskii is able to oviposit on Japanese apricots only lasts from mid- to late April (fruit diameter: 12~16 mm). When the diameter of the fruit is >16 mm, the pit of the Japanese apricot hardens and larvae have difficultly penetrating the stone. Therefore, the most effective method of controlling this pest is to spray orchards with a control agent 2~3 times, at 5 d intervals, beginning in mid- April.

• Korean Journal of Environmental Agriculture
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• v.38 no.1
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• pp.23-33
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• 2019

BACKGROUND: The golden apple snail(GAS, Pomacea canaliculata Lamarck) is an invasive freshwater snail. It has occurred 34 years since the introduction of the GAS to the Korea. The GASs have been used recently for weed control in wet rice cultivation. The GASs'adaptability to the environment of GAS has been improved and the GASs devour the young stage of the crops as well as weeds. METHODS AND RESULTS: We surveyed the survival area of the snails throughout the country during the winter seasons from 2000 to 2017 and crop damage due to GASs in 2017. Local maximum, minimum, and average air temperatures were monitored daily. The surveyed regions for the survival of the GASs in winters were Gangjin, Goheung, Shinan, Haenam, Gimhae, Haman, Busan, Jeju, and Seogwipo. The survival durations at low temperatures were 12 hours at $-5^{\circ}C$, 1 day at $-3^{\circ}C$, 2 days at $-1^{\circ}C$, 10 days at $0^{\circ}C$, and over 30 days at $3^{\circ}C$. The eggs of GASs were not able to overwinter. The overwintering condition of the GAS needed a water depth of 10-20 cm with well formed mud. Crop damages caused by the overwintering GASs occurred in rice and water dropwort. CONCLUSION: The overwintering GAS was first identified in Haenam, South Korea 2000 after introduction of the GAS. The overwintering area of GAS expanded to the mid-southern parts of Korea. We propose that it has not yet become a pest to rice or any other crop.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.535-542
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• 2012

This study was carried out from 2011 to 2012 in order to analyze the cultivation technology system by six organic rice cultivation types in the southern provinces for the purpose of utilizing organic rice farming guidelines. This surveys were conducted by site visit on 8 counties and 115 farms in southern area. Cultivation technology system by six organic rice cultivation types were cultivated by the principle of minimum input or non-input. cropping systems, a mixture of barley and rice, or rice green manure crops were grown. Cultivars were mixture of the local cultivars and Japanese varieties. Soil were managed by a self-manufactured compost, indigenous microorganisms and barley straw without any fertilization. Pest control was mainly practied by purchased eco-friendly organic materials or herbal medication residue and indigenous microbial self-manufactured. Weed was controled by snails and barley straw. In addition, considering the restore of a longtail pitching shrimp and grasshoppers, the fuction of environmental ecology of six organic rice cultivation type proved to be excellent all. Meanwhile, the productivity of the organic farming per 10a were the order of Life and environment > Natural circulation > Stevia > Ji jang > Art and nature > Taepyoung of Farming Methods, but the farmers received prices showed the opposite tendency. Simple profitablity did not show a big difference. But, the productivity of all type of the organic farming were lower then the conventional farming. Finally, If we want to conduct safety and easy farming, we can suggest stevia farming, Natural circulation farming and life and environmental farming out of 6 organic rice cultivation types.

• Asian Journal of Turfgrass Science
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• v.18 no.4
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• pp.221-229
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• 2004

Biological control of lepidopterous insect pests, Agrotis segetum, Artogeia rapae, Mamestra brassicae, Plutella xylostella, Spodoptera exigua, and S. litura with entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae isolated from Gyeongbuk province were investigated. Mean lethal concentration ($LC_50$) values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of A. segetum larvae were $1.2\times10^7\;conidia/m\ell$ and $5.2\times10^6\;conidia/m\ell$, respectively. $LC_50$ values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of A, rapae larvae were $1.2\times10^7\;conidia/m\ell$ and $5.2\times10^6\;conidia/m\ell$, respectively. $LC_50$ values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of M. brassicae and P. xylostella, larvae were $1.5\times10^6\;conidia/m\ell$, $9.7\times10^5\;conidia/m\ell$, $3.0\times10^6\;conidia/m\ell$ and $1.4\times10^6\;conidia/m\ell$, respectively. $LC_50$ values of B. bassiana and M. anisopliae against $2\cdot3rd$ instar of S. exigua, and S. litura larvae were $6.3\times10^6 \;conidia/m\ell$, $2.6\times10^6\;conidia/m\ell$, $1.6\times10^7\;conidia/m\ell$ and $3.4\times10^6\;conidia/m\ell$ respectively.