• Research in Plant Disease
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• v.15 no.1
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• pp.23-29
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• 2009

Cooking oil and yolk mixture (COY), a environmentally acceptable plant protection agent, and COY+$CaCO_3$+neem oil mixture were studied to control the powdery mildew occurring on eggplant, paprika, cherry tomato and maturity tomato in glass houses and vinyl houses during 2005 to 2007. The morphological changes of the pathogenic fungi on the leaf surface before and after treatment of COY were observed. COY made of rape seed oil and COY+$CaCO_3$+neem oil mixture were sprayed three times with 5 days interval to foliar parts of eggplant, paprika and tomato and the disease development were examined 5 days after final spray. In eggplant, the control efficacy of COY to powdery mildew was 94.6%. In paprika, the control efficacy of COY to powdery mildew was 91.6% and that of COY+$CaCO_3$+neem oil mixture was 96.2% that revealed little higher than COY itself. In tomatoes(cherry or maturity tomato), the control efficacy of COY were about 91 %, however, when COY mixture were sprayed to tomato leaves and stems the powdery mildew was controlled completely. Typical and healthy mycelia, conidiophores and condia were observed through scanning electron microscope in COY unsprayed leaf surface, on the other hand destroyed and winkled mycelia and conidiophores were observed in COY treated leaves regardless host plants nor taxonomic differences of fungi.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.156-160
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• 2014

The stabilities of four limonoidal substances including azadirachtin A, azadirachtin B, deacetylsalannin and salannin were investigated both in controlled aquatic and soil conditions. The half-life of the total limonoid for neem extracts and its two commercial biopesticides was estimated 86.6-173 days in water under air, while degradation of the compounds was detected below 10% after eight weeks in deoxygenated water. The half-life in dry soil was estimated 43.3-57.7 days, and there was a similar degradation pattern with in aerobic water condition. In case of wet soil condition, the total bacteria of the soils ranged 6-8 log CFU/g soil for during the experiment, and the half-life of the total limonoid was 6.4-12.3 days. From the result, the fast limonoid degradation in wet soil environment was the result of both chemical oxidation and microbial degradation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.183-197
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• 2007

Field trial was conducted at the Research Farm of the Katsina State Agricultural and Rural Development Authority during the farming season of 2004 with a view to evaluate/determine the efficacy of some selected plant-derived biopesticides against the insect pests of cowpea as well as their effect on yield. The variety of the cowpea used was IT86D-719 and the plant derived biopesticides evaluated during the trial were chilli pepper, garlic, ginger, neem, sweetsop and tobacco. The experimental field was ploughed, harrowed and thereafter ridged before the commencement of the 2004 planting season. A total of twenty one (21) experimental plots were demarcated and arranged into seven treatment plots. The size of each plot was $5m{\times}4m$ while interspaces between adjacent plot and blocks were 1m and 2m, respectively. Results of the experiments showed that all the plant-derived biopesticide treatments were significantly (p>0.05) better than control treatment. The order of effectiveness of the treatments was tobacco (80-90%), sweetsop (75-85%), garlic (70-80), neem (72-78%), chilli pepper (60-70%) and ginger (30-50%). Furthermore, yield result corresponded positively with the effectiveness of the treatments. Results of the present finding suggest the use of tobacco, sweetsop and garlic as promising biopesticides in the control of cowpea insect pests.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.149-159
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• 2017

This study was conducted to develop an organic control method of tobacco whitefly (Bemisia tabaci) by using cooking oil and yolk mixture (COY). Mortality rate against B. tabaci nymph on paprika leaf was 94.5% by COY treatment and it was not significantly different from that by pyridaben treatment. Mortality rate against B. tabaci nymph on tomato leaf was 41.4% by COY treatment and it is lower than that by neem extract. But mortality rates of B. tabaci adult by COY and neem extract were no significant differences. Oviposition of B. tabaci were decrease respectively 75.8% and 52.7% by COY on paprika and tomato leaves. In paprika and tomato greenhouses, damaged by B. tabaci, COY was sprayed twice and resulted in respectively 100% and 38% control values.

• Genomics & Informatics
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• v.20 no.3
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• pp.33.1-33.17
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• 2022

Nervous necrosis virus (NNV) is a deadly infectious disease that affects several fish species. It has been found that the NNV utilizes grouper heat shock cognate protein 70 (GHSC70) to enter the host cell. Thus, blocking the virus entry by targeting the responsible protein can protect the fishes from disease. The main objective of the study was to evaluate the inhibitory potentiality of 70 compounds of Azadirachta indica (Neem plant) which has been reported to show potential antiviral activity against various pathogens, but activity against the NNV has not yet been reported. The binding affinity of 70 compounds was calculated against the GHSC70 with the docking and molecular dynamics (MD) simulation approaches. Both the docking and MD methods predict 4 (PubChem CID: 14492795, 10134, 5280863, and 11119228) inhibitory compounds that bind strongly with the GHSC70 protein with a binding affinity of -9.7, -9.5, -9.1, and -9.0 kcal/mol, respectively. Also, the ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties of the compounds confirmed the drug-likeness properties. As a result of the investigation, it may be inferred that Neem plant compounds may act as significant inhibitors of viral entry into the host cell. More in-vitro testing is needed to establish their effectiveness.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.275-281
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• 2022

We investigated the occurrence pattern of the Asian Corn Borer, Ostrinia furnacalis in job's tears, and we tested the field control effects of 5 insecticides and 3 eco-friendly materials. Adults of O. furnacalis began to occur in May and have passed three generations until the end of October. As results of the field test, five insecticides (novaluron, lufenuron, spinetoram, cyclaniliprole, flufenoxuron) and three eco-friendly materials (gosam extracts 90%, neem extracts 60%, citronella oil 30 + derris extracts 20 + cinnamon extracts 10%) showed high control effects against O. furnacalis in two different areas, and no phytotoxicity even at double dose of pesticides.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.287-290
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• 2011

Environment friendly agricultural material products (EFAMs) in current market were evaluated for their insecticidal or acaricidal activities. EFAMs were evaluated against Tetranychus urticae, Plutella xylostella, Myzus persicae and Nilaparvata lugens in spray method. Several EFAMs indicated high control value in spray method. Hatchability of T. urticae was relatively high after EFAM treatment. some materials show high insecticidal activities against P. xylostella larvae but not against eggs. Few mete rials showed more than 80% insecticidal activities against M. persicae and N. lugen. The control value of more than half the materials for pest control was lower than 60%. EFAMs containing S. flavescens, neem oil and Rape showed higher control value.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.279-282
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• 2011

This study was carried out to development the environment-friendly control method of Myzus persicae using Beauveria bassiana and Environment-friendly agricultural materials (EFAM). Germination rate the dried conidia of B. bassiana was 90 percent at $24{\sim}27^{\circ}C$ temperature condition. Mortality of M. persicae was 56.7% at $1{\times}10^7$ cfu/ml conidia concentration. Four EFAM such as Pachungtan, Wangjungwang, Newbiodakill, Muginchon were low toxicity to B. bassiana growth. Among them, Muginchon (derris extract) and Wangjungwang (neem extract) could have synergistic effect to aphid mortality when mixing treat with B. bassiana, which protection value was 99% in 3 days after treat.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.9-13
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• 2011

This study was carried out to control the disease of wood-cultivated ginseng(panax ginseng) using natural materials. Four fungi spices such as Pythium ultimum, Alternaria alternata, Fusarium oxysporum and Rhizoctonia solani which caused disease of the wood-cultivated ginseng were investigated. The infection of these fungi causes symptom on roots, stems and leaves. The leaves became dry and die. The disease caused by Pythium ultimum can be prevented by using friendly environmental materials like Chamaecyparis obtuse essential oil and Wormstop. Alternaria alternata and Fusarium oxysporum might be prevented by using wormstop extracted from Neem tree(Azadirachta indica). No substance tested effectively prevents the growth of Rhizoctonia solani.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.114-119
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• 2012

We have conducted 4 experiments to develop the most environmental and effective use of the two-fluid fog system to prevent and exterminate whiteflies in tomato cultivation. In particular, these experiments used Vitamini tomatoes grown in stand-alone greenhouses at Buyeo Tomato Experiment Station as subjects. Each experiment utilized the fog system in a different way. The first experiment provided the control group, which was subject to the two-fluid fog system without additional humidity control. In the second experiment, the two-fluid fog system controlled the humidity level to be above 70%. The third and the fourth experiment utilized natural substances, which were 1.5 mg/L of Neem Oil and 2 mg/L of Oleic acid respectively, without additional humidity control. From the first experiment, we could observe that a simple use of the two-fluid fog system decreased the density of whiteflies in the greenhouses. This impact of the fog system on whiteflies was greater in the second experiment. By comparing the first and the second experiment, we concluded that whiteflies are more effectively prevented by maintaining a higher humidity level via the fog system's smaller water droplets that float in the air for longer time than the standard fog system in rather dry condition. In the third and the fourth experiments, the extermination level was 78% and 76.4% respectively, comparing only 53% in the first experiment without the humidity control. Therefore, using the natural substances in addition to the humidity control increases the extermination effectiveness. Considering the similar results from the 3rd and the 4th experiments, Oleic acid has a greater appeal for its lower price. Using the two-fluid fog system to both control the humidity on a daily basis and spray the substances for occasional extermination would reduce labor cost and increase production in an environmental way.