• The Plant Pathology Journal
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• v.18 no.5
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• pp.231-236
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• 2002

Bemisia tabaci Genn. is an important pest worldwide because of its ability to cause damage by direct feeding and its role as a vector of some viruses including geminiviruses. The first report of Tobacco leaf curl virus (TLCV), a Geminiviruses, in Indonesia was in 1932 when the virus was found infecting tobacco plants in Central Java. The characteristic symptoms of TLCV included upward curling of the leaf edge, vein thickening, and sometimes the occurrence of enation on the underside of the leaves. Basic studies were carried out to elucidate the characteristics of TLCV transmission by its vector, B. tabaci. A single whitefly was able to transmit the virus and the efficiency of transmission was increased when the number of adult whiteflies was increased up to 20 per plant. Inoculation access period of 1 h could cause transmission up to 20% and the optimum inoculation access period was 12 h. Acquisition access period of 30 minutes resulted in 70% transmission while 1(10% transmission occurred with a 24-h acqui-sition access period. The virus was proven to be persistently but not transovarially transmitted. Discrete fragments of 1.6 kb were observed when polymerase chain reaction method was applied to detect the virus in viruliferous nymphs and individual adults of B. tabaci, while no bands were obtained from non-viruliferous nymphs and adults.

• Research in Plant Disease
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• v.12 no.1
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• pp.1-4
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• 2006

During visiting North Korea from 2001 to 2005, I have had a few chances to observe and discuss several North Korean scientists for the seed production program and also, the occurrence of potato pests. Healthy seed production, especially in the early generations, e.g. the production of virus-free starting materials as well as in vitro pre-basic seeds (G0) by hydroponics and basic seeds under netted houses according to her new national seed potato program of Academy of Agricultural Science, Pyongyang, North Korea, has been done well so far. Some major pests occurred, however, in the early generations such as pre-basic seed (G0) in greenhouse, basic seed (G1) in screenhouse, foundation seed-I (G2) and even ware potatoes in the fields are Phytopitthora infestans, Spongospora subterrunea, Ralstonia solanacearum, Pythium spp. and some viruses such as Potato virus X, Potato virus Y, Potato leafroll virus, and also larger potato ladybeetle, greenhouse whitefly and potato tuber moth. Therefore, the success of healthy seed production in North Korea will be thoroughly depended on the pest control and the multiplication of virus-free seed stocks in the isolated areas, especially where no infected potatoes are grown.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.463-477
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• 2019

This study was conducted to compare the community structure and biodiversity of epigeic spiders between pear fields cultivated by integrated pest management (IPM) and organic methods. This is the first study of this kind to be conducted in Korea. Eighty-four spider species from 22 families were identified among the collected 2,489 arthropods, with 754 individuals being sampled from IPM fields and 1,735 individuals from organic fields. Generally, Theridiidae, Linyphiidae, Lycosidae, Agelenidae, Gnaphosidae, and Salticidae were the dominant spider families in the pear orchard regardless of the farming methods, and species richness and abundance were higher in organic fields than in IPM fields. The dominant species were the wolf spiders (Lycosidae) and stone spiders (Gnaphosidae), and their cumulative abundance was 70.7% in IPM fields and 72.7% in organic fields. The community structure between organic and IPM fields was heterogeneous, with a 45% similarity level. Biodiversity, species richness, abundance, and species diversity index were higher in organic fields than in IPM fields, and significantly different between the farming methods. Seasonal fluctuations in biodiversity were similar in both IPM and organic fields. The species richness and species diversity index increased and the abundance decreased in the second half of the cultivation period. This study on the community structure and biodiversity of epigeic spiders, which form one of the most important predator groups, will provide principal ecological and faunistic information required to maintain the biodiversity of useful arthropods in agricultural ecosystems and help implement sustainable agriculture based on the active use of natural enemies.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.439-444
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• 2016

Maruca vitrata is a main insect pest against crops of Vigna species (V. angularis and V. radiata) and Sesbania sesban in Fabaceae, but the life cycle of the insect is unclear in Korea. In order to know over-wintering possibility, its stage of the insect, over-wintering entry season, and the first adult emergence season of the next year, we investigated over-wintering rates of the insect in outdoor conditions in Suwon ($37^{\circ}16^{\prime}N$ $126^{\circ}59^{\prime}E$ 35ASL). In all colonies which the rearing for larvae, pupae and eggs started after mid-September, adults did not emerge within the year, and all insects died before next June. In several trials for over-wintering of larvae and pupae in soil, all insects died, too. Larvae stored during specified periods at low temperatures (10 and $13^{\circ}C$) did not emerge. From the results, it was postulated that M. vitrata does not have an adaptability to temperature below zero, and cannot over-winter in Suwon area.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.413-420
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• 2017

Sugarbeet cyst nematode (Heterodera schachtii) has recently been detected as a severe pest of Chinese cabbage fields in Korea. Two studies were performed to evaluate the effect of inoculation density of H. schachtii and plant age of Chinese cabbage on the final population of the nematodes. Chinese cabbage inoculated with high inoculation density (4 juveniles or eggs/g soil) showed significant differences in the number of cysts, females and eggs. The 40 day- old plants inoculated with high nematode densities yielded the highest nematode populations after 30 and 60 days of inoculation, compared with other plant age groups (0, 20, 30 day-old)used in the experiment. We, thus, summarize that, maximum nematode multiplication rates are made on comparatively older plants at the high nematode densities. Therefore, taking plant age into consideration at the transplanting of Chinese cabbage was recommended for the management of H. schachtii.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.9
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• pp.1132-1140
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• 2016

According to global trend, despite the overall scale of agricultural industry has been downsized, agriculture accommodating cutting-edge ICT technologies has been proliferated, and various timely-issued relevant researches have been on progress to deploy the future food cultivation. In this paper, we propose an effective nutrient management system with web-based monitoring with functionality of controlling temperature, humidity, pH (hydrogen ion), EC (Electric Conductivity), LED and cooling fan to maintain the hydroponic nurturing environment being optimal. In this paper, in order the arduino hardware and java software are employed to control the nurturing environment automatically in optimal fashion. In proposed system, due to the usage of WiFi router with the socket communication and DB-assisted Web server with proper interfaces, it allows to facilitate the management to keep monitoring and controling overall hydroponic nurturing environment. Since the proposed Web-based management system provides the superior reliability, the short nurturing period and the robustness to the pest by controlling LED emitting color rather than conventional system, so it can be applied and appropriate for in-house vegetable factory overcoming limitation of time and location.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.1
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• pp.133-137
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• 2010

The perilla leaf pyralid moth, Pyrausta panopealis Walker (Lepidoptera: Pyralidae), is a serious pest damaging to leaf perilla. In order to establish the life parameters of P. panopealis for eventual purpose of control, the developmental span of each stage was investigated under five temperature regimes ($20^{\circ}C{\sim}30^{\circ}C$). The larval period of P. panopealis was longest as 26.8 days at $20^{\circ}C$ and shortened as temperature goes up to $30^{\circ}C$ as 11.3 days. Survivorship of the larval P. panopealis was the highest at $27.5^{\circ}C$ as 82.5%, whereas that of other temperatures ranged from 40% ($20^{\circ}C$) to 60.0% ($30^{\circ}C$), indicating that the P. panopealis appears to favor somewhat higher temperature. In addition to larval period, the duration of egg, prepupal, and pupal period also were shortened sharply as temperature goes up, whereas the duration of adult stage shortened a maximum of only two days as temperature goes up. After the perilla leaf pyralid moths were successfully stabilized in indoor environment the larvicidal efficacy of ten on-the-market environmentfriendly agricultural materials (EFAMs) that were previously selected from the result of other moth species was tested. Seven of the ten tested showed more than 90% of mortality within 12 hrs and reached nearly up to 100% within 24 hrs, but the remaining three showed less than ~70%.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.42-55
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• 1984

The direction of scientific researches on tree improvement and forest management in several universities and research institutes in Japan can be summarized as follows: They put a great emphasis on sugi, Cryptomeria japonica and cypress, Chamaecyparus oblusa which are two major conifer species largerly planted in the Japanese forestry. In the research of sugi, a great concern has been made in evaluating inheritance of forest tree, quantitative characters and genetic parameter of growth, and in breeding for resistance to diseases and insects and to all the natural calamities. Interaction between environmental conditions and genetic nature of tree can be concerned factors in relation with forest damage, together with silvicultural conditions and pest infestation. Selfing hybrids of $F_1$ made from crossing twisted-leaf sugi, defomity leaf type and midori sugi, normal leaf type segregated the normal needle, twisted needle, green leaf and albino leaf type. It seemed that separation of many defomity individuals can be governed by two dominant complementary genes and from the near loci of which it was detected lethal genes. 52% of Japanese forestry is occupied by the small forest landowners like Korean forestry. This made difficulty for forest improvement such as progressive afforestation and for capital accumulation form forestry. The Forest Corporation was established at first in 1959 to aming at productive forestry structure and forest management, and afforestation. For these purpose, 35 Forest Corporations are at moment operating throughout Japan. However, investment in forestry business becomes less attractive since the wage in forest production duction increased in higher trend. than timber price. Therefore, an artifical afforestation becomes yearly decreased. At present. the self-sufficient rate of timber production in Japan is about 35%, and so a great effort is being made to increase self-sufficient rate of timber production.

• Korean Journal of Environmental Agriculture
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• v.40 no.2
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• pp.142-147
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• 2021

BACKGROUND: Agricultural use and pest control purposes of pesticides may lead to livestock products contamination. Thiodicarb and its degraded product, methomyl, are carbamate insecticides that protect soya bean, maize, fruit, and vegetables and control flies in animal and poultry farms. For maximum residue limit enforcement and monitoring, the JMPR residue definition of thiodicarb in animal products is the sum of thiodicarb and methomyl, expressed as methomyl. This residue definition was set to consider the fact that thiodicarb was readily degraded to methomyl in animal commodities. And therefore the simultaneous analytical method of thiodicarb and methomyl is required for monitoring in livestock products. METHODS AND RESULTS: The study was conducted using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and HPLC-MS/MS to determine the thiodicarb and methomyl in livestock products. The limit of quantitation (LOQ) was 0.01 mg/kg for livestock products, including beef, pork, chicken, milk, and egg. The coefficient of determinations (r²) for the calibration curve were > 0.99, which was acceptable values for linearity. Average recoveries at spiked levels (LOQ, 10LOQ, and 50LOQ, n=5) in triplicate ranged from 73.2% to 102.1% and relative standard deviations (RSDs) were less than 10% in all matrices. CONCLUSION: The analytical method was validated for the performance parameters (specificity, linearity, accuracy, and precision) in livestock products to be acceptable by the CODEX guidelines.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.105-115
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• 2019

Saline or alkaline condition in soil inhibits growth of most crop plants and limits crop yields in many parts of the world. Augmenting an alkaline soil with alkali-tolerant bacteria capable of promoting plant growth can be a promising approach in expanding fertile agricultural land. Near-shore environments of Dokdo Island, a remote island located in the middle of the East Sea, appear to have patches of seawater-influenced haloalkaline soil that is unsupportive for growth of conventional plants. To exploit metabolic capacities of alkali-tolerant bacteria for promoting plant growth in saline or alkaline soils, we isolated of alkali-tolerant bacteria from near-shore soil samples in Dokdo and investigated properties of the isolates. Alkali-tolerant bacteria were selectively cultivated by inoculating suspended and diluted soil samples on a plate medium adjusted to pH 10. Fifty colonies were identified based on their $GTG_5$-PCR genomic fingerprints and 16S rRNA gene sequences. Most isolates were affiliated to alkali-tolerant and/or halotolerant genera or species of the phyla Firmicutes (68%), Proteobacteria (30%) and Actinobacteria (2%). Unlike the typical soil bacterial flora in the island, alkali-tolerant isolates belonged to only certain taxa of terrestrial origin under the three phyla, which have traits of plant growth promoting activities including detoxification, phytohormone production, disease/pest control, nitrogen-fixation, phosphate solubilization or siderophore production. However, Firmicutes of marine origin generally dominated the alkali-tolerant community. Results of this study suggest that haloalkaline environments like Dokdo shore soils are important sources for plant growth promoting bacteria that can be employed in bio-augmentation of vegetation-poor alkaline soils.