• Journal of Environmental Science International
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• v.30 no.2
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• pp.191-194
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• 2021

This study aimed to provide information and data for the management of insect breeding farms by identifying the appropriate density when rearing Protaetia brevitarsis larvae. The breeding box of the insects was filled with 2 L of fermented sawdust on a 50 × 35 × 15 cm sheet of plastic, and the density of the treatments was 200, 300 and 400 P. brevitarsis in the first, second, and third larval stages. Each treatment was repeated five times, and the sawdust medium was replaced three times (10 intervals). The experiments were conducted for a total of 30 days from March 1, 2020. Overall, 200 P.brevitarsis in the first, second, and third larval stages reared in the breeding box had a higher average survival rate and lower average mortality rate, thereby contributing to efficient production. In conclusion, this result suggests a way to increase production efficiency through the environmental management of insect breeding farms.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.23-26
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• 2003

A neem based product, Suneem-G (granules) alone as well as in combination with urea was tested against root-knot nematode, Meloidogyne incognita, on okra (Abelmoschus esculentum) in clay pots of 20-cm-diameter, containing 2 kg sterilized soil, inoculated with 2,000 freshly hatched second stage juveniles (J$_2$) of M. incognita. Application of different dosages of Suneem-G with or without urea significantly reduced nematode population and incidence of galling on okra roots and increased vegetative plant growth compared with the untreated control. Suneem-G with urea was the most effective and its effect increased with the increase of dosage. Suneem-G 6 g＋urea 25 g per pot gave maximum plant growth and root gall reduction, as plants shoot and root lengths were increased by 84 and 58% and root galling was reduced by 58%, respectively. The lowest dosage of Suneem-G alone, 2 g per pot increased shoot and root lengths of plants by 25.7 and 17%, respectively, and reduced root galling by 24%. The lowest effect was recorded in the pots treated with 25 g urea alone; shoot and root lengths were increased and root galling was decreased by 14% each.

• Korean journal of applied entomology
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• v.45 no.1 s.142
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• pp.67-74
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• 2006

Korean entomopathogenic nematodes were introduced into cultural management of turfgrasses to enhance white grub control in golf courses for saving labour and expenses and contribution to giving safe playing and working places for golfers and superintendents by environmentally friendly control strategy. The turfgrass height influenced efficacy of entomopathogenic nematodes. Efficacy was higher at short turfgrass both in pot using Galleria mellonella larvae and in golf courses using 2nd instar of Exomala orientalis and Ectinohoplia rufipes as baits. Aeration increased the efficacy of entomopathogenic nematodes which were lower virulent. Pre-aeration was more effective than post-aeration. Exomala orientalis larval population was reduced 80.4 and 66.0% in the pre-aeration and post-aeration with entomopathogenic nematode, Steinernema carpocapsae Pocheon strain compared to 35.4% in the no aeration treatment.

• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.79-86
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• 1977

Four experiments were carried out under farmer's field conditions to determine economic threshold levels of major rice pests aad attempt a reduction in the number of insecticide applications. In the experiments were included check treatments, insecticide schedules representing the official recommendations to farmers, and several corrective treatments. A careful record was kept of insect pest densities and disease incidence. i) In the north at Suweon and Icheon where Chilo suppresalis. (Walk.), the striped rice borer, was active in the first generation, no significant yield differences were obtained between plots receiving several insecticide applications and those left totally unprotected. The mean yields were high (5.2-7.6t/ha). ii) First generation borer activity rising to $8.6\%$ injured tillers was below the economic threshold since no yield reduction was recorded in either japonica varieties or the high-yielding Tongil variety. iii) Evidence was obtained thst berer damage was made good by replacement of infested tillers (compensatory growth), C. suppressalis populations were always low in the second generation. iv) The experimental results obtained at Suweon and Icheon do not justify the present official recommendations of 6-7 pesticide applications. v) further south at Iri a substantial yield reduction occurred due to an early outbreak of stripe disease transmitted by Laodelphax striatellus (Fallen), the small brown planthopper; a mean of 1-2 individuals/hill was recorded immediately after transplanting. C. suppressalis probably contributed to this yield reduction. vi) Several applications against the vector failed to prevent the rapid spread of stripe to the susceptible variety in the Iri experiment: in surrounding fields the resistant Tonsil varivety was ralatively unaffected. vii) Pests of lesser importance were Nephotettix cinctieps (Uhler), Nilaparvata lugens (Stil), Sogatella furcifera (Horv..), and leaf miners.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.331-338
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• 2014

Cystatins (CSTs) are reversible and competitive inhibitors of C1A cysteine proteases, corresponding to papain-like cathepsins in plants and animals. A viral CST (CpBV-CST1) was identified from a polydnavirus, Cotesia plutellae bracovirus (CpBV). Our previous study indicated that a transient expression of CpBV-CST1 interfered with immune response and development of Plutella xylostella larvae. To directly demonstrate the protein function, this study produced a recombinant CpBV-CST1 protein (rCpBV-CST1) using bacterial expression system to determine its inhibitory activity against cysteine protease and to assess its physiological alteration in insect immune and development. The open reading frame of CpBV-CST1 encodes a polypeptide of 138 amino acids (${\approx}15kDa$). rCpBV-cystatin protein in BL21 STAR (DE3) competent cells containing a recombinant pGEX4T-3:CpBV-CST1 was over-expressed by 0.5 mM IPTG for 4 h. In biological activity assay, the purified rCpBV-CST1 showed a significant inhibition against papain activity. It inhibited a cellular immune response of hemocyte nodule formation in the beet armyworm, Spodoptera exigua. Moreover, its oral administration retarded larval development of the diamondback moth, Plutella xylostella in a dose-dependent manner. These results suggest that CpBV-CST1 may be applied to control insect pest populations.

• Parasites, Hosts and Diseases
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• v.33 no.1
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• pp.19-26
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• 1995

Ecological studies of Aedes togoi, the vector of malayan filariasis, were ci,wind out at Tolsando, Yosu and Sokcho area in 1991. The adult population of Aedes togoi was continuously appeared from the first week of April to the end of November showing the highest density in .truly. The larvae of Aedes togoi were found at rock pools from March to December in Sokcho area and the density was highest in July and August, whereas in the southern coastal area (Yosu), the larvae were found throughout the year and the density was the highest in Tune. The rate of larvae inhabited below 0.5% salinity was 45.7% in Sokcho and 51.7% in Yosu. The feeding activity of Aedes togoi was nocturnal, with the peak period of 01 :00-03:00 hours. Indoor feeding activities were slightly higher than outdoors showing the biting ratio of 1 :0.8 (indoor: outdoor). The average number of Aedes togoi attracted to CO2 gas was 8.5 whereas 117 Anophelei sinensis was attracted. The result indicates that CO2 is not an effective attractant for host seeking of Aedes togoi compared to Anopheles sineteis. The most common place was bedroom with 54.5% of total collections and next to stock place (18.2%), floor(9.1%) and kitchen (9.1%).

• Korean journal of applied entomology
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• v.31 no.4
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• pp.396-415
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• 1992

To investigate identification of species distribution state, population density of plant parasitic nematodes and damaged state by parasitism of nematodes with soil samples taken from major cultivating area of medicinal herbs in Kyungbuk districts are summarized as follow; total species belonging to genera in families were identified from 43 different medicinal herbs. The dominant nematode species on medicinal herbs was Meloidogyne hapla by 55.6% of field infection. Damaged state by parasitizm of Root-knot nematode, M. hapla, M. incognita are severed 15 medical plant except P. japonica, infected field were in 54.5~88.0%, and highered in population densities of 2nd larvae, Gall, Egg sac. Percentage of yield-decrease were 57.8% in A. gigas, 49.1% in P.japonica. Lighten effect of M. spp. by cropping system were lowered in population density in Rice+Paeony than Paeony+Paeony in paddy field, and also lowered in Sesame+Paeony or one year fallowing after harvest Paeony than Red pepper+Pseony, Paeony+Paeony in upland field.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.420-432
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• 2011

Population dynamics of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), were modeled and simulated to compare the temperature effects of air and tomato leaf inside greenhouse using DYMEX model simulator (pre-programed module based simulation program developed by CSIRO, Australia). The DYMEX model simulator consisted of temperature dependent development and oviposition modules. The normalized cumulative frequency distributions of the developmental period for immature and oviposition frequency rate and survival rate for adult of greenhouse whitefly were fitted to two-parameter Weibull function. Leaf temperature on reversed side of cherry tomato leafs (Lycopersicon esculentum cv. Koko) was monitored according to three tomato plant positions (top, > 1.6 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at same three positions using a Hobo self-contained temperature logger. The leaf temperatures from three plant positions were described as a function of the air temperatures with 3-parameter exponential and sigmoidal models. Data sets of observed air temperature and predicted leaf temperatures were prepared, and incorporated into the DYMEX simulator to compare the effects of air and leaf temperature on population dynamics of greenhouse whitefly. The number of greenhouse whitefly immatures was counted by visual inspection in three tomato plant positions to verify the performance of DYMEX simulation in cherry tomato greenhouse where air and leaf temperatures were monitored. The egg stage of greenhouse whitefly was not counted due to its small size. A significant positive correlation between the observed and the predicted numbers of immature and adults were found when the leaf temperatures were incorporated into DYMEX simulation, but no significant correlation was observed with the air temperatures. This study demonstrated that the population dynamics of greenhouse whitefly was affected greatly by the leaf temperatures, rather than air temperatures, and thus the leaf surface temperature should be considered for management of greenhouse whitefly in cherry tomato grown in greenhouses.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.52-64
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• 2008

Aged sewage sludge with food waste leachate sludge or paper mill sludge was fed to earthworm (Eisenia fetida) populations and the effect of it on feeding and growth rate of earthworm population was investigated. Feeding rate of earthworm population on sewage sludge aged with food waste leachate sludge for 30 days was higher than that aged for 10 and 20 days. At 90 days after feeding, the density of earthworm population decreased regardless of aging period. And earthworm population growth to next generation was blocked by sewage sludge. The feeding rate and the density of earthworm population aged with paper mill sludge for 20 days were higher than that on sewage sludges aged for 10 and 30 days. Until 90 days after feeding, the density of earthworm population increased regardless of aging period of sewage sludge, however, since then decreased. There were comparatively higher feeding rate and growth rate of earthworm population on the sewage sludge which had been mixed with paper mill sludge and aged for 20 days, which rendered the probable pretreating method for vermicomposting sewage sludge.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.45-51
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• 2009

This paper presents sequential sampling plans for evaluating the pest density based on complete counts from probe in a rice storage warehouse. Both maize weevil and Indian meal moth population showed negative binomial dispersion patterns in brown rice storage. For cost-effective monitoring and action decision making system, sequential sampling plans by using the sequential probability ratio test (SPRT) were developed for the maize weevil and Indian meal moth in warehouses with 0.8 M/T storage bags. The action threshold for the two insect pests was estimated to 5 insects per kg, which was projected by a matrix model. The results show that, using SPRT methods, managers can make decisions using only 20 probe with a minimum risk of incorrect assessment.