• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.257-259
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• 2002

With development of Circuit technology, accuracy of dielectric or induction heating apparatus was developed. This study aims at realization of food insecticidal apparatus using dielectric heating. Equipment to measure grain's permittivity or vermin's permittivity and expectation for heating temperature by computer simulation is necessary for construction of the system. And the effect of extermination of vermin for food was confirmed by experiment using the system.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.85-90
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• 1998

A series of experiments were carried out to determine the effect of seed dressing application of chemicals on the early occurring rice insect pests. The number of small brown planthopper adults per 3hills in seed-dressing plot of Imidacloprid WS (Im WS) was 1.6 and its control efficacy was over 90%, compared with that of untreated plot. Rice water weevil was observed in the density of 8.8 larvae per 5 hills seed-dressed Im WS plots(showing 95.5% of control efficacy). Control efficacy of Im WS and Im GR against adult weevils lasted for 26 days after treatment and was higher than that of Carbofuran GR. Rates of injured stems by rice stem maggot and injured leaves by rice leaf miner were 3% and 3.7% in Im WS treatment plot respectively. Seed germination rate after seed dressing with recommended dosage (3 g/seed kg) of Im WS was 71 % on the 1st day and increased on 5th day up to that of untreated seed. The residual amount of Im in seed dressing plot was 0.11 ppm in rice roots and 0.05 ppm in leaves on the 40th day after treatment. Residual effect of Im WSI sustained for 50 days with over 95% insecticidal effect for the rice water weevil and over 90% for the brown planthopper. Quantity of the chemical applied in the field was calculated as 0.084 kg a.i./ha in seed dressing and 0.3 kg a.i./ha in seed box treatment, respectively It took 1 hour to treat insecticide by seed dressing, 2.5 hours by seed box applying, and 3.6 hours by water surface releasing per 990 $m^2$.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.123-128
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• 2002

This study was carried out to test the effects of temperatures between 2$0^{\circ}C$ and 3$0^{\circ}C$ on the reproduction and development of the rice water weevil, Lissorhoptrus oryzophilus. Preoviposition periods were much longer (17.2 to 51.0 days) in the overwintering adult females collected in March than those collected in May, regardless of temperature. Oviposition periods, however, were longer (16.9 to 22.0 days) in the adult females collected in May than those collected in March at the same temperatures. The longer oviposition period observed in the females collected in May were directly associated with higher fecundity. Egg periods were shortened from as temperature increased, but the hatching rate was highest (100%) at 27$^{\circ}C$. The developmental periods from egg to adult were shortened as temperature increased : from 77.9 days at 2$0^{\circ}C$ to 38.3 days at 3$0^{\circ}C$. The developmental zero point temperature (T) and the total effect temperature (K) for egg were 16.3$^{\circ}C$ and 62.1 dgree days, respectively. The T and K from egg to adult emergence were 13.9$^{\circ}C$ and 577.6 dgree days, respectively. The adult females of the first generation did not oviposit at 2$0^{\circ}C$, but did at $25^{\circ}C$ and 3$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) increased as temperature augmented. Net reproductive rate (Ro) per generation was highest (75.3) at $25^{\circ}C$.>.

• Korean journal of applied entomology
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• v.27 no.2
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• pp.117-124
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• 1988

An Investigation of insect pests in rice stored was carried out in Jeonnam region of Korea. The total of 2 class, 7 orders 16 families and 25 species were recorded in Lepidoptera; 8, Coleoptera; 11, Orthoptera; 1, Thysanura 1, blattaria; 2, Hymenoptera; 1 and mites; 2 spe-cies. The important species among them were Sitotroga cerealella, Ephestia cautella, Paral-ipsa gularis, Poldia, in Lepidoptera, and Sitophilus orzae, Oryzaephilus surianmensis, Cryptolestes ferrugineus, Tribolium castaneum, Tenebroides mauritanicus, Attagenus japonicus, in Coleoptera and Blatella germanica, in Blattaria and Acarus siro Petrobia latens, in mites. The duration of maximum occurrence were the late June to mid July for Sitotroga cerealella, the mod July to early August for Oryzaephilus surianmensis the mid July to August for Tribolium castaneum, the early July to late July for Sitophilus orzae, the mid June to early July for Attagenus japonicus the mid June to late Spetember for Blatella germanica and the late April to late May for Acarus siro and Petrobia latens, respectively in investigation, Blatella germanica(Blattaria) which was no problem in stored rice insect till now was mainly distributed a coastal plain and period of occurrence was long amount of occurrence was great. Rice weevil has 4 generations under natural conditions and the peak of 1st perood time was ranged from middle of jun. to last decade of Jun., 2nd period was from the lats decade of Jul. to first decade of Aug., 3rd period was from middle of Sep. to late Sep., 4th period was middle of Oct. to early Nov.

• Korean Journal of Environmental Agriculture
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• v.31 no.3
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• pp.286-292
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• 2012

BACKGROUND: The carotenoid-biofortified (PAC) rice was generated by inserting phytoene synthase (Psy) and carotene desaturase (Crtl) genes isolated from Capsicum annuum cv. Nockwang and Pantoea ananatis into the genome of a conventional variety of rice (Nakdongbyeo). In our present study, we studied the effects on insecticide susceptibility of Rice Water Weevil (Lissorhoptrus oryzophilus). METHODS AND RESULTS: The L. oryzophilus were fed on carotenoid-biofortified (PAC) rice and its near non-genetically modified (GM) counterparts (Nakdongbyeo) under $25{\pm}1^{\circ}C$, humidity of $60{\pm}5%$, and photoperiod 16L:8D for more than 60 days. Ten adults were soaked in the Clothianidin SC solution for 5 second in different concentrations, and were detected the mortalities after 24, 48 and 72 hours respectively. Every experiment was conducted with three replications. The cumulative mortalities of L. oryzophilus exposed to Clothianidin SC were similar between two types of feed administration. CONCLUSION: The results of this study suggested that carotenoid-biofortified rice might not affect the insecticide susceptibilities of Lissorhoptrus oryzophilus.

• Applied Biological Chemistry
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• v.17 no.1
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• pp.54-62
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• 1974

62 specimens of deteriorated rice which were collected all over Korea, were classified according to their color outlooks, and the causitive microorganisms were isolated and identified. The following results were observed; 1. 62 specimens of deteriorated rice were classified according to color outlooks into 7 types; reddish yellow, light reddish yellow, light gray yellow, light reddish yellow, light gray yellow, light red, ligt gray, dark gray and rice weevil type. 2. The isolated microorganisms from 62 specimens of deteriorated rice were 44 species, 5 genera of molds, 1 species of yeast, and 14 species, 4 genera of bacteria. 3. The frequently observed microorganisms which caused the deterioration were Asp. glaucus group, Asp. oryzae, Asp. candidus, and Asp. versicolor. Among bacteria, Bacillus was dominant. 4. The relationship between color outlook types and the deterioration causing microrrganisms was not definite, but Pen. islandicum from reddish yellow, Asp. candidus and Asp. clavatus from light reddish yellow, Asp. glaucus group, Asp. candidus, Asp. versicolor and Asp. fumigatus from light red, Asp. oryzae from light gray yellow, and Asp. glaucus group and Pencillium species from light gray and dark gray were chiefly isolated. 5. As mycotoxin producing fungi, Asp. fumigatus, Pen. citrinum, Pen. islandicum, Asp. flavus, and Asp. ochraceus were detected, but their growth frequencies were not very high to be problems except Pen, islandicum which infected an imported rice sample heavily.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.361-370
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• 1982

The effects of climatic factors on organisms lire variable and complex, and it, however, can be interpreted in terms of those on the distribution and those on the population densities. The distribution of an organism may largely be determined by the temperatures, except some temporal organisms which are depended on the air mass movements. Population density of an organism is determined by various climatic factors, such as previous winter temperature, temperature of growing season and rainfall. The start of growing season of the rice plants has been shifted to earlier since last decade in Korea. This may mean that the overall climatic condition during the growing season might be considerably different from those in past years, and such a difference in climatic conditions might have close relation with the recent status of the diseases and insect pests through direct effects on the physiology and population dynamics of the organisms, as well as through on the biotic associations of the pest organisms. The white back planthopper and brown planthopper have become the key insect pests in Korea in recent years. They are migratory and have high reproductive pontentials and more generations than average residential insects. The synchronization of the migrants and physiological condition of the rice plants seems to be the important factors in relation to the recent outbreaks of these insects; the high reproductive rate can be obtained with the growth stage of rice being 30-50 days after transplanting. The modication of the microclimate associated with high plant density and some other introduced new cultural techniques also have some relation with the outbreak. The key diseases of the rice are the blast disease, sheath blight and the bacterial leaf blight. For the rice blast, the seedling blast and leaf blast during the early growing season and the neck blast, have become more serious, the former may be related to hotbed nursery and the later may be related to the high humidity in early August, and synchronization of the heading time which has been shifted to early part from middle or late part of August. In general, for the rice diseases, the development of the new races have been the most serious which are largely resulted from the introduction of the new varieties, but it also seems to be related with the prolonged periods of the favorable condition associated with the shifted growing seasons. In general, the diseases and insect pest problems have become much more variable and complex, and control measures should be based on the thorough knowledge of the ecology of the pest organisms, that is, effects of various environmental factors on the disease cycle; spore release, spore deposition, infection, colonization and sporulation of the disease organisms, and those on the development, reproductive potentials, dispersal, age specific responses of the insects. The well organized real-time pest management systems, such as alfalfa weevil management system developed at the Purdue University in U.S., is the prime importance for the implementation of the pest management principles.

• Korean journal of applied entomology
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• v.5_6
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• pp.33-38
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• 1968

쌀바구미의 유충을 3기로 구분하여 각종 농도의 Apholate를 처리하여 그의 치사율$\cdot$발육속도$\cdot$산란수$\cdot$불임률 및 그의 지속성 여부를 조사하여 다음과 같은 결과를 얻었다. (1) 당대 치사율은 농도가 높아짐에 따라 높아 켰으며, 유령기 처리시의 치사율은 노령기 처리시보다 높았다. (2) 차대 치사율은 처리된 성에 따라 차가 있었고 전체적으로 자충 처리시가 자충 처리시보다 높아 치사돌연변이 유기율이 웅충 처리시에 높아짐을 알 수 있었다. (3) $0.5\%$ 이상의 처리구에서는 우화 성충 중에 각종 기형이 출현하였으며, 그 수는 농도가 높아짐에 따라 컸다. (4) 산란수의 감소는 자충 처리시가 웅충 처리시보다 심하였으며, 이것은 Apholate의 난자형성에 미치는 직접적인 영향이라고 생각된다. (5) 발육속도는 노령기 처리시가 유령기 처리시보다 늦어지며, 그 효과는 농도의 증가에 따라 높아진다. 차대의 생육기간은 자충 처리시가 웅충 처리시보다 길어졌다. (6) 화학적 불임제는 당대의 영향뿐 아니라 차대에도 그 영향력이 지속된다.

• Korean journal of applied entomology
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• v.4
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• pp.67-74
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• 1965

The work on the 'Studies of radiosensitivity' in Korea has been initiated since 1959 by the author at various institutions in home and foreign countries, and more than 20000 of plant materials in 73 varieties and 41 kinds are treated under varied conditions for the studies of radiosensitivity in plants. However, a study of the susceptibility to radiation in insect pests as well as their biological effects has not been previously reported in this country. During the year of 1964 and 1965, near 50000 of insects at the stages of adult, egg, larva and pupa in 14 different kinds are irradiated under acute X and gamma rays to investigate the behavior of growth and lethality after irradiation, and thrir general tolerances to radiations are compared by the kind of insects, stage of growth, radiation sources and exposured dosages. Through the experiments, it is shown that the lethality in most of insects are high as several kilo roentgens above and no significant effects on pupation. emergence, and oviposition in the treated generation at the dose of 3 Kr. below, but in the following generation , the rice stem borer for instance, no oviposition or decreased laying is observed from the dosages at 3 Kr. to 1 Kr., and the hatching was possible from 1.5 Kr. below of irradiated larvae although laying and hatching are seemed in normal. In general, the lethal dose $50\%$ of tested infect materials at the larval stage can he classified some what 60-80 Kr. for Pine caterpillar, Fall webworm, Camphor silk moth and their relatives, at 40-60 Kr. for Gypsy moth, Monley prominent and some relatives and at 20-30 Kr. for House fly, Rice weevil, Pine sawfly etc. Plant parasitic nematodes such as Hirschmannia and Paratylenchus shown very high resistance to radiation and the LD-50 is observed from 100 Kr. or above. A concept to evaluate the radiosensitivity in insects by taxological family line as a practical measure is not answerable yet, but it ran he solved within the near future through the continuing experiments.

• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.199-208
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• 2010

To investigate a comparison of rice yield and quality between organic and conventional cultivation, study for occurrence of rice diseases carried out in rice (Oryza sativa L.) field of Noahn and Bannam region. The results obtained as following: 1) Bactericide and insecticide were applied twice and four times at Noahn and Bannam region in conventional cultivation (C.C) of rice field, respectively, it was applied twice at two region in organic cultivation (O.C). Rice strip virus, leaf blast, neck blast, sheath blight, bacterial leaf blight, rice water weevil, rice leaf folder, and plant hoppers were occurred mainly in rice field. Leaf blast, neck blast, and rice leaf folder were occurred highly at O.C compared with C.C. 2) Growth level of rice in clum and panicle length was lower at O.C than C.C. Number of panicles per hill was by 0.6 higher at O.C than C.C. Number of panicles per hill was by 0.6 higher at O.C than C.C in Noahn region. Number of spikelets per panicle, grain filling ratio, brown/rough rice ratio, and weight of 1,000 grains was lower at O.C than C.C. Number of panicles per hill was by 0.8 lower at O.C than C.C in Bannam region. Number of spikelets per panicle and grain filling ratio was higher at O.C than C.C while brown/rough rice ratio was lower at O.C. Total yield percentage of rice in O.C was level of 84% at Noahn region and 94% at Bannam region compared with C.C. 3) Head rice percentage was lower at in O.C than C.C at two region. Protein and palatability (Toyo value) were lower at O.C than C.C in Bannam region causing occurrence of neck blast and rice leaf folder by oversupply of nitrogen fertilizer. Protein, whiteness, and palatability (Toyo value) were adequate level at O.C in Noahn region by lower nitrogen fertilizer.