• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.71-80
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• 2017

This study was conducted to investigate the application effect of Lysobacter antibioticus HS124 (gelatinase and chitinase producing microorganism; GCM) for the improvement of soybean yield and control of stink bug. Our results showed that the yield of GCM-treated soybean increased by 17.0, 20.3, 19.0, and 25.6% in the experimental field sites of Muan-gun, Sunchang-gun, Gwangju 1, and Gwangju 2, respectively, compared to the yield of the soybean obtained by conventional practice treatment (CPT); however in the Gimjae-si, the yield decreased by 10.6%. Results in both pods and seeds $plant^{-1}$ were significantly increased in Gwangju 2 by the GCM cultured broth treatment (GCMT). Ratio of 3 seeds $pod^{-1}$ in Sunchang-gun was statistically significant between GCMT and CPT, however, the result in the other field showed no significance. Germination rate was only statistically improved by GCMT in Gwangju 2 field site. GCMT reduced the appearance of stink bug in all experimental field sites except in Gimjae-si. The soybean seed damage by stink bug was no significance in all of treatments. Therefore, GCMT could improve the productivity of soybean and also control the infestation of stink bug.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.173-180
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• 1987

Symptom development and disease severity of Phytophthora blight in the sesame plants varied depending upon age of the plants tested, inoculation method, watering method, and inoculum density in both susceptible Suweon 9 and Suweon 26 and moderately resistant B-67 and IS 103 sesame lines to Phytophthora nicotianae var. parasitica when inoculated. However, successful differentiation of the sesame lines for varietal resistance was possible using 20-day old seedling, inoculation by soil infestation, saturated soil water condition by half immersion of pots in water tank, and 200 sporangia per one ml of inoculum. Spraying or soil inoculation to 70-day old plants also was effective in differentiating the varietal resistance. By the screening method Suwon 26 showed 100％ diseased plants and symptom severity index 9.0, while B-67 showed 20% diseased plants and symptom severity index 1.7. The rating scale given was from 0 through 9. For example, the scale 0 signified no symptom development, 5 signified discoloration of basal part of stem, and 9 signified discoloration of stem more than 10 cm high above the soil surface with blighted leaves. Differentiation in symptom severity also was made by percentage of the lesion area. Results evaluated using both parameters were well corresponded in varietal reaction of sesame to Phytophthora blight.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.101-105
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• 2008

Effects of different application of nematicides (fosthiazate 5% G, ethoprophos 5% G, and diazinon 34% EC) for the control of Aphelenchoides fragariae in strawberry were evaluated in a greenhouse experiments. Mother strawberry (Fragaria grandiflora) cv. Yeohong were dipped in solution of nematicides (fosthiazate or ethoprophos at 2.5 g a.i./liter in $20^{\circ}C\;or\;46^{\circ}C$) for 10 min. and planted in a greenhouse for dipping treatment. For the compare, mother strawberry were dipped in hot water for 10 min. without chemicals. For soil treatment, fosthiazate or ethoprophos at 3 kg a.i./ha were mixed into soil. For foliar spray, diazinon at 3.4 g a.i./liter was sprayed at foliage until runoff. At 40, 80, and 100 days after planting, runners were harvested from each treatment and the rate of nematode infestation and the number of nematodes per plant were examined. After 100 days of planting, mother strawberry plants dipped in fosthiazate solution (2.5 g a.i./liter, $20^{\circ}C$) for 10 min. produced more number of healthy runners and reduced % of infected runner as much as 90% and also had fewer nematodes per runner. Fosthiazate was more effective than ethoprophos. Foliar application of diazinon was reduced A. fragariae populations only in early season. Hot water treatment and nematicide soil treatment were less effective.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.161-168
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• 2013

Soybean cyst nematode (Heterodera glycines Ichinohe) is one of the serious soybean [Glycine max (L.) Merr.] pests in major soybean producing countries. The objective of this study was to investigate of Heterodera glycines type using the five SCN infested soybean field soils and was to evaluate resistance to the soybean cyst nematode HG 2.5.7 type on soybean varieties and germplasms. The five SCN contaminated soil samples were collected from the three provinces on November 2011 in Korea, and eggs were cultured on early spring season in 2012. For the second study, a total fifty nine soybean varieties and germplasms were tested by infestation of HG type 2.5.7 in the greenhouse. Soybean cyst nematode HG types were investigated from five locations, HG 2 (race 1) type at Donghae, HG 2.5 (race 1) type at Jeongseon and Hapcheon, HG type 2.5.7 (race 1 or 5) at Yeongwol, and HG 1.2.7 (race 5) type at Haenam locations in present study. No Korean soybean varieties and germplasms were observed with SCN resistant trait to the HG type 2.5.7. Average SCN female index were calculated with 82.7% in 59 plant materials. Our results could be provided useful information to develop a SCN resistant cultivar in Korea.

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.221-227
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• 2004

Protocol was established for production of virus free healthy seeds using meristem ($0.3-0.5\;\cal{mm}$ in size) culture and field management under net house condition in tomato. The isolated meristem was found well established in MS liquid medium containing $0.1\;\cal{mg}\;1^{-1}\;of\;GA_3$. For shoot and root development either from primary meristem or from nodal segment of meristem derived plants, semisolid MS medium having $0.5\;\cal{mg}\;1^{-1}$ of IBA was found most effective. The elimination of the studied viruses (ToMV, CMV, ToLCV) in meristem-derived plants was confirmed by DAS-ELISA test. For field management of the virus eradicated meristem-derived plants, use of net house was found very effective measures to check viral vector visit and eventually infection. The meristem-derived plants were vigor and high yielder than the native seed derived plants and produced healthy seeds. Due to stop vector visit, no viral symptoms were observed in both $R_1\;and\;R_2$ plants cultivated in net house condition. Starting of viral infestation was observed in $R_2$ generation when they were planted in open house condition without control of vector visit. Therefore, for management of viral diseases, use of virus free meristem derived plantlets and their subsequent cultivation in soil under net house condition without using any vector killing insecticide can be recommended for producing healthy seeds in tomato. The developed protocol for environmentally healthy tomato seed production in Bangladesh may be used in the countries having similar tropical like environment conducive for viral vector visit.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.261-268
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• 2014

This work was conducted to identify mungbean genotypes showing yield stability and resistance to mungbean yellow mosaic virus (MYMV) disease. Sixteen genotypes were evaluated in a randomized complete block design with two replications for two years (2011 and 2012) at three locations (Gazipur, Ishurdi and Madaripur) of the Bangladesh Agricultural Research Institute. An analysis of variance exhibited significant effects of genotype (G), environment (E), and genotype ${\times}$ environment ($G{\times}E$) on grain yield. Among eight agronomic characters, the principal component 1 (PC1) was always higher than the PC2. Considering $G{\times}E$ interaction, BM6 was the best genotype at all three locations in both years. Based on grain yield and stability performance, BM6 ranked first while the worst performing genotypes were BM1 and G10. Based on discrimination and representation, Gazipur was identified as an ideal environment for these mungbeans. Relationship between soil-plant analysis developments (SPAD) value was positive with yield but negative with MYMV severity. BM6, G1 and G2 were considered as promising sources of resistance for low disease score and stable response across the environments. The environment proved to have an influence on MYMV infection under natural infestation. A positive correlation was observed between disease score and the temperature under natural growing condition.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.282-289
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• 2012

The root rot of pepper (Capsicum annuum L.) caused by Phytophthora capsici is one of the most important diseases affecting this crop worldwide. This work presents the evaluation of the capacity of Streptomyces griseus H7602 to protect pepper plants against Phytophthora capsici and establishes its role as a biocontrol agent. In this study, we isolated an actinomycete strain H7602 from rhizosphere soil, identified it as Streptomyces griseus by 16S rRNA analysis and demonstrated its antifungal activity against various plant pathogens including P. capsici. H7602 produced lytic emzymes such as chitinase, ${\beta}$-1,3-glucanase, lipase and protease. In addition, crude extract from H7602 also exhibited destructive activity toward P. capsici hyphae. In the pot trial, results showed the protective effect of H7602 against pepper from P. capsici. Application of H7602 culture suspension reduced 47.35% of root mortality and enhanced growth of pepper plants for 56.37% in fresh root and 17.56% g in fresh shoot as compared to control, resulting in greater protection to pepper plants against P. capsici infestation. Additionally, the enzymatic activities, chitinase and ${\beta}$-1,3-glucanase, were higher in rhizosphere soil and roots of pepper plants treated with H7602 than other treated plants. Therefore, our results indicated a clear potential of S. griseus H7602 to be used for biocontrol of root rot disease caused by P. capsici in pepper.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.12-19
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• 1998

The pattern of rice cultivation in Korea is changing from hand transplanting and machine transplanting into direct-seeding for low input and cost-down practices. However, there are still some obstacles to establish the direct-seeding cultural practices because of poor seedling stand, lodging, and weed infestation. In particular, there were much more and wide weed occurrence in direct-seeding rice as compared with the transplanted rice. Weed occurrence in terms of dry weight of weeds was highest in dry direct-seeded rice followed by sowing an puddled soil, sowing on submerged soil in order as compared with transplanting with infant rice seedling. Echinochloa crux-galli was a common dominant weed with 35~44% distribution in any direct-seeding methods. The dominant weed species were E. crux-galli, Cyperus difformis, C. serotinus, and Ludwigia prostrata in dry-seeded rice. The dominant weed species in water-seeded rice were E. crus-galli, Eleocharis kuroguwai, Scirpus juncoides, and Monochoria vaginalis. Yield loss of rice due to weeds at weedy condition was 96% in dry direct-seeded rice. In water-seeded rice, yield loss was 61%, whereas yield loss was 40% in machine transplanting with infant rice seedling.

• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.194-215
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• 2021

Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

• Journal of Korean Society of Forest Science
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• v.50 no.1
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• pp.56-71
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• 1980

To study the changes of vegetational composition of each plant successional stage of Pinus densiflora forest caused by pine gall midge damage, Thecodiplosis japonensis, located in Kyonggi-do area, the middle part of Korea, four districts, Anseong, Yongin, Gwangju, and Gapyeong, were selected according to the length of insect damage duration. The forest in the Anseong district was the noninfested one selected as the check. And forests in Yongin, Gwangju, and Gapyeong were the recent]y damaged, severely damaged, and damage prolonged ones in sequence. It was considered that this order could be in concord with the gradual transition of plant successional stage. In view of temperature, precipitation and soil factors, these four districts were sited within the same environment. Four survey plots were selected from each district and the distance between them was 3~4 km. Then again four subplots were set within a plot. Through needle accumulation after insect infestation, light intensity, soil moisture content, and the amount of soil organic matter were increased and these conditions could create a favorable environment enabling the new species invasion and their growth. These were naturally closely related with the increase in quantity of Pinus densiflora defoliation. After considerable time lapse, the quantities of above mentioned factors decreased with the development of the new substitute tree species. It was found that Quercus mongolica was an excellently substitute tree species come first in this studied area. Species diversity increased to a degree at the early stage of the duration of pine gall midge damage and decreased thereafter. As the same manner, similarity index value between plots in the same district decreased to a degree and increased thereafter. This was linked admittedly with the increase and decrease of tree species and evenness. Synthesizing above mentioned results, the process of plant succession studied quantitatively by changes of relative density and relative importance value, it can be concluded that Pinus densiflora forest gives way to Genus Quercus forest in which Genus Lespedeza and Genus Rhododendron species become as subdominance species after removal of the Pinus densiflora trees damaged by pine gall midge.