• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.72-78
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• 2016

BACKGROUND: Entomopathogenic fungi have been studied to develop for biological control agents as an alternative to chemical control agents in insect pest management. This investigated to determine the optimal culture conditions in ceramic balls for maximal sporulation of entomopathogenic fungi Beauveria bassiana M130 by use rice bran extract.METHODS AND RESULTS: METHODS AND RESULTS: A culture of entomopathogenic fungi for 12day on rice bran extract(1:8, w/v) incubated in ceramic matrix at 28℃. Natural zeolite ceramic ball was high production of 4.2×108 conidial/mL. The culture condition optimized initial pH, temperature, rice bran extract concentration, adhesives substance and concentration of NaCl, respectively. The high production of spore optimal conditions were temperature 28℃, initial pH 3, rice bran extract 3 mL, starch 33 g, 5 % NaCl and sopre suspension 7 mL, respectively.CONCLUSION: This study was carried out for the mass production of entomopathogenic fungi conidia recover rate 65% in matrix of natural zeolite ceramic ball, and to develop ingredient-used formulation of Beauveria bassiana M130 conidia for biological control agents.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.445-455
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• 2014

The pear sucker (Cacopsylla pyricola) is the most important insect pest in Korea. The hatching rates of overwintered adults laid eggs were observed at 10, 13, 18, and $22^{\circ}C$. The liner model was draw as Y=0.00277X+0.00146(Y=developmental rate, X=temperature) about temperature and developmental rate to eggs. The developmental threshold temperature to eggs was assumed about $-0.83^{\circ}C$. The egg hatching timing over 50% as the accumulated temperature by day maximum temperature $6^{\circ}C$ over from 1st February in 2008, 2009 and 2011 was 429.7, 417.6, and 424.3 degree $^{\circ}C$, respectively, was 3 to 7days before full blooming in pear orchard. On the other hand, the abamectin 1.8EC, lime sulfer, machine oil and 13 kinds of eco-friendly materials were not shown the control effect to the eggs. To mixed stage of pear sucker, the eco-friendly materials over 90% control value were 4 kinds such as a mixture of Azadiractin A+B, Nimbin, Salanin, Meliantriol and Vepol after twice application as 21st May and 5th June in pear growing season, in 2012.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.347-354
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• 2018

In order to setting the control standard of Chinese cabbage pests using a drone, the downward wind speed, spraying width, and the number of falling particles and particle size were examined using a water sensitive paper with spray different heights (3, 4, 5 m) and flying speeds (3, 4 m/sec). Fore kinds of pesticides for aviation control were used to test the perfect lethal concentration and dose for major pests of Chinese cabbage such as Plutella xylostella, Spodoptera exigua and Spodoptera litura. The number of falling particles in spraying pesticides with drones was 80.5% on the upper side, 14.8% on the vertical side, and 4.7% on the back side. The number of falling particles as different spray heights were 3 m = 53, 4 m = 40 and $5m=39particles\;cm^{-2}$. The number of falling particles as different flying speeds were $3m\;sec^{-1}=62$ and $4m\;sec^{-1}=25particles\;cm^{-2}$. In the laboratory test, the perfect lethal concentration and dose of Plutella xylostella was chlorfenapyr SC (20 times, $0.5{\mu}l$) and bistrifluron chlorfenapyr SC (25 times, $0.5{\mu}l$). The perfect lethal concentration and dose of Spodoptera exigua was chlorfenapyr SC (20 times, $1{\mu}l$), bistrifluron chlorfenapyr SC (20 times, $1{\mu}l$), and chlorfenapyr SC (20 times, $1{\mu}l$) and bistrifluron chlorfenapyr SC (20 times, $0.5{\mu}l$) for Spodoptera litura. Therefore, the main pest control method of Chinese cabbage using drones is 20 times diluted chlorphenapyr SC or bistrifluoruron-chlorphenapyr SC, sprayed at 3 m height by $3msec^{-1}$ of going speed. This spraying method will be effective for control of Chinese cabbage pest.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.437-443
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• 1995

Concerns on use of excess amount of chemical fertilizier and pesticide in current farming system turns both of the producer and consumer of agricultural products to an organic farming which use a less chemicals and more natural manure. Rice-duck farming system is one of the strategy to meet the purpose and this experiment was carried out to find the effect of the rice-duck farming system on the quality and yields of rice. 20day-old rice seedling were mechanically transplanted in sandy-loam paddy field and 21 day-old ducks were raised from 3 weeks after transplanting with population of 30 heads per 10a. The plots were consists of reduce fertilizer(70%) with and without duck-raising. The conventional fertilizer treatment without duck-raising was used as check. The results obtained are summarized as follows. The weeds population of test plots which were raised with duck for 3 consecutive years was less than that of test plots without duck-raising, though a speciffic population of Echinochola crusgallis were increased. The weed control effect was higer in duck-raising than in check at the maximum tillering stage but, not at later stages of rice plant. It was found that the small animals and insects inhibiting in the rice field were reduced by duck-treatment, however, there were also damages of grass leaf roller at booting stage in the plots of duck-raising. In rice-duck plot, dark green leaf color were found: 41.8 of SPAD value than 38.6 of SPAD in check plot. Higher root activity and surface soil oxidation were also observed in rice-duck plot than check plot. 3% of the increase in yield was observed by duck-treatment. However, the expected increase of the palatability wsa not observed. This may be due to the unfavorable weather conditions during the rice growing in this expriment.

• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.49-58
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• 2012

Greenhouse whitefly, $Trialeurodes$ $Vaporariorum$, is the most important insect pest in environmental friendly tomato production. Natural enemies, $Nesidiocoris$ $tenuis$ and environmental friendly agricultural materials (EFAM) are major control agents in Korea. The aim of the present work is to evaluate release time of $N.$ $tenuis$ in controlling of $T.$ $vaporariorum$ and to select environmental friendly agricultural materials (EFAM) to suppress both $T.$ $vaporariorum$ and $N.$ $tenuis$ which if the density were high causing necrotic rings. Six EFAM selected to control of $Trialeurodes$ $Vaporariorum$ in three times spray with seven days intervals. Three EFAM showed high mortality 67.7-70.5% in spray after release plot but low in release after spray plot. It should be careful to spray with $N.$ $tenuis$. When $N.$ $tenuis$ were early release at 7 days after transplanting which before occurring and establishment of greenhouse whitefly, it could suppress the density. Extracts of bead tree + matrin, matrin 1, Chrysanthemum showed high mortality on $T.$ $vaporariorum$ adults and $N.$ $tenuis$. The results suggested that this three EFAM could be control agents of the damage of necrotic rings from $N.$ $tenuis$.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.299-305
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• 2023

Bemisia tabaci is one of polyphagous insect pests that transmits Tomato Yellow Leaf Curl Virus (TYLCV) and Cassava Brown Streak Disease (CBSD). Insecticides are primarily applied to control B. tabaci, but it has limits due to the development of resistance. As a result, a fixed precision sampling plan was developed for its integrated pest management (IPM). The tomato plants were divided into top (more than 130cm from the ground), middle (70 cm to 100 cm above the ground), and bottom (50 cm or less above the ground) strata, before visual sampling of the larvae of B. tabaci. The spatial distribution analysis was conducted using Taylor's power law coefficients with pooled data of top, middle, bottom strata. Fixed precision sampling plan and control decision-making were developed with precision levels and action threshold recommended from published scientific papers. To assess the validation of the developed sampling plans, independent data not used in the analysis were evaluated using the Resampling Validation for Sampling Plan (RVSP) program.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.62-69
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• 2013

The black cutworm, Agrotis ipsilon (Hufnagel), damages various cultivated crops and it can also be a serious pest of turfgrass, especially on golf courses. Essential oils have potential as alternative control agents for insect pests. Sixteen essential oils (anise, camphor, cinnamon, citronella, clove, fennel, geranium, lavender, lemongrass, linseed, neem, peppermint, pine, thyme, turpentine and tea saponin) and paraffin oil were assessed in the laboratory, the green house and field trials for their efficacy against black cutworms in turf. Treatment of potted cores of perennial ryegrass turf with anise, cinnamon, neem, paraffin or turpentine reduced black cutworm damage in a greenhouse trial, and in a similar trial, applying neem oil at 4000, 2000 and 1000 ppm resulted in 100, 100 and 64% mortality, respectively, of black cutworms. Weight of survivors at the 1000 ppm rate was 5- fold less than weight of comparably-aged controls. Neem oil (2000 ppm) reduced growth of black cutworms feeding on treated clippings. A high rate of neem oil followed by irrigation (0.1 L of 20000 ppm neem oil with 0.9 L watering/$m^2$) was more effective than a lower concentration (1 L of 2000 ppm neem oil/$m^2$) against $2^{nd}$ and $3^{rd}$ instars in potted turf cores and field plots, respectively. However, not even the aforementioned higher rate effectively controlled $4^{th}$ instars in the field.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.411-418
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• 2013

The black pine bast scale, Matsucoccus thunbergianae is one of the most serious insect pest in Japanese black pine, Pinus thunbergii forest in Korea. Insecticidal activity of 10 folds hot water extracts from 7 herbal plants (Atractylodes lancea, Eugenia caryophyllata, Lonicera japonica, Melia azedarach, Quisqualis indica, Sophora flavescens and Taraxacum mongolicum) were tested against different stage of M. thunbergianae using spray method both in laboratory and field. Efficacies of herbal extracts were different depending on stage of M. thunbergianae. Q. indica sprayed with hand sprayer produced the highest corrected mortality of 95.7% on intermidiated nymph stage, however, A. lancea produced the highest corrected mortality (51.3%) on pupae of M. thunbergianae in laboratory. Q. indica and A. lancea were highly effective against female M. thunbergianae in laboratory, however, corrected mortality was lower than other stage (40.0%). Efficacy of Q. indica was similar to effective insecticide, fenitrothion 50% EC against M. thunbergianae in field trials. These results indicated that Q. indica could be an environmental friendly control agent of M. thunbergianae.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.194-200
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• 2011

Diamondback moth (DBM, Plutella xylostella L.) is known as the most destructive pest of cruciferous crops worldwide. As most insecticides targeted to mainly larval stage, new insecticides which have hatching-inhibitory or ovicidal activity could be more efficient to control DBM. Therefore, we developed an easy and efficient method for screening ovicidal activity of DBM eggs using aluminum foil. The aluminum foil ($4{\times}12$ cm) coated with filtered juice of chinese cabbage leave (hereinafter called oviposition foil) exposed to 300 newly-emerged adults for 24 hours inside the rearing container. The oviposition foils were replaced every 4 days consecutively after mating, but it was better to discarded over then. Oviposition foil were divided into 6 to 12 pieces depending on egg mass volume. After dipping into test solutions for 10 seconds using faucet, oviposition foil pieces were placed into common petri dish, and then investigated hatchability. The effect of methanol solvent (50%) for 10 seconds dipping on the toxicity against DBM eggs was negligible. In addition, whether covering the petri dish or not should be dependent on nature of active compounds tested. With applying the new bioassay method, methanol extracts from 50 plants were tested the ovicidal activity to DBM eggs. Among them, four plant extracts; Angelica tenuissima root, Lycium chinense root, Cnidium officinale root and Polygala tenuifolia root, showed high ovicidal activity of over 90% control efficacy, against DBM eggs.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.51-60
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• 2017

The striped fruit fly, Bactrocera scutellata, infests pumpkin flowers. Males are attracted to raspberry ketone (RK) and feed the attractant. This study was conducted to determine essential techniques to develop a male annihilation technique (MAT) of this insect pest. Effective attractants were screened in laboratory and field conditions. Both males and females were responsive to methyl eugenol (ME) in laboratory, though no flies were attracted to ME traps in field conditions. In contrast, cuelure (CL), which is a chemical derivative of RK, was effective to attract males of B. scutellata in both laboratory and field conditions. However, RK was equivalent or superior to CL when they were formulated in a form of wax dispenser. A pyrethroid insecticide along with the attractant was effective to attract and kill B. scutellata. Funnel trap was useful for MAT to confirm and count dead flies. These results indicate that MAT against B. scutellata consists of RK and bifenthrin in a wax type formulation, which is installed to a funnel type of trap. These essential factors would be useful to develop MAT applicable to control B. scutellata in fields.