• Research in Plant Disease
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• v.15 no.1
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• pp.1-7
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• 2009

Viruses diagnosed on crops including rice plants from farmers or agricultural extension agencies cover the country were 11 species including Broad bean wilt virus 2 (BBWV2) in 2008. Tomato spotted wilt virus (TSWV) was the most important virus having the detection rate of 22.9%. Two viruses of Tomato yellow leaf curl virus (TYLCV) and Tobacco leaf curl virus (TLCV) inducing leaf yellow and curl diseases on tomatoes were occurred newly with the detection rate of 12.2% and 4.0%, respectively, in 2008. Rice stripe virus (RSV) was occurred on 869.5 ha mainly at Jindo and Haenam areas in Jeollanamdo province. At Jindo area, 12 plots were damaged severely with the infected hill rate of 83.8%. At the main production area of oriental melon at Seongju, almost all fruits from whole sale market at Seongju were infected with Cucumber green mottle mosaic virus (CGMMV) as the detection rate of 87%. The areas occurred TSWV in Korea were 25 totally from 2003 including 7 areas newly reported in 2008 including Naju in Jeoallanamdo. TSWV could be reduced as 0.1 % from 5.3% by covering insect proof net in vinyl house after chemical soil sterilization. Tomato yellow leaf curl disease was occurred on April in 2008 at Tongyoung area in Kyeongsangnamdo, and detected continuously at 13 areas, 7 in Kyeongsangnamdo, 4 in Jeollabukdo and 2 in Jejudo. Potato spindle tuber viroid (PSTVd) was occurred abruptly in a confined space of a civil breeding greenhouse and a cultivar evaluation field followed by disuse 17.4 M/T of potato tubers. No PSTVd was detected at 17 fields cultivated the related potatoes to the bred company by RT-PCR.

• 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.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.115-120
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• 2012

Weed control is of fundamental importance when planting cereal crops, particularly during the establishment phase. Weeds compete for nutrients, water and light, and can severely threaten the survival and early growth of newly planted crops. Field experiment was conducted to evaluate the effect of ethanol treatment on the weed control efficacy in cereal crops in protected vinylhouse. Five treatments like water, 25 L, 50 L, 75 L, and 100 L per $m^{-2}$ at 2% ethanol were applied and covered with vinyl on 10 days before foxtail millet seeding. After that, foxtail millet seeds were sown on June 20 at $60{\times}10cm$ planting distance and weed control efficacy was recorded at 30, and 50 days after seeding based on the dry weight. Soil oxidation-reduction potential was recorded -200~-400 mV after treatment 2 days. Weed control efficacy of at 75 L, and 100 L per $m^{-2}$ was observed 92%, 84% in 2% ETOH, respectively. Yields of foxtail millet at 75 L, and 100 L per $m^{-2}$ were 1,570 kg $ha^{-1}$, 1,230 kg $ha^{-1}$, respectively.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.413-422
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• 2014

In national water quality policy, it changed previous regulation method that focuses on concentration of pollutants in effluent water to the way that regulates total amount of pollutants. The target of water quality in watershed of each river was set up, as the government instituted Total Maximum Daily Loads(TMDL). In order to accomplish successfully TMDL, it requires that the amount of pollutant loads discharged from point and nonpoint pollutant source should be investigated. This study, therefore, conducted the monitoring of the stormwater runoff at field region in farming area. And pollutants loads and unit loads discharged from field region results is calculated. As a result, the concentration of pollutants were calculated as follows: 10.5 BOD mg/L, 19.6 $COD_{Mn}$ mg/L, 4.5 TN mg/L and 2.4 TP mg/L. The unit load of BOD, $COD_{Mn}$, TOC, TSS, TN and TP discharged from field region, also, were determined to $31.8kg/km^2/yr$, $56.7kg/km^2/yr$, $8.5kg/km^2/yr$, $560.9kg/km^2/yr$, $8.3kg/km^2/yr$ and $5.1kg/km^2/yr$, respectively. It was identified that there were some differences of unit loads between the results obtained from this study and previous one. To calculate exact unit loads, therefore, long term monitoring should be conducted.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.293-297
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• 2012

A new asiatic lily cultivar 'Point' was derived from a cross between $Lilium$ $concolor$ var. $partheneion$ and 97-5 with orange colored petals made in 2000. The selection and the survey for the flower characteristics were conducted from 2005 to 2008 by using vinyl tunnels and greenhouse at Highland Agriculture Research Center, NICS, RDA. Based on flower color, 'Point' cultivar belongs to orange red group (O-R N30C). There was lots of spots in petal. The flowers had brown stigma and dark brown pollen. The stem color was dark purple. The flowering date was July 8. The plant height was 88.2 cm and flower numbers were 5.4 ea. The length and width of petal were 6.3 cm and 3.2 cm, respectively. The flower size was smaller than that of 'Prato' cultivar. The number of leaves was 12.2 ea. The length and width of leaves were 9.2 cm and 1.1 cm, respectively. The weight and circumference of bulb were about 24.6 g and 11.6 cm, respectively. 'Point' cultivar had resistance to bulb rot disease. The flowering duration was 16.1 days. The preference was good to 4.1 on 5 grades. 'Point' cultivar was registered as a new variety with No. 3446 in Korea Seed and Variety Service on April 2011.

• Research in Plant Disease
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• v.29 no.1
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• pp.88-93
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• 2023

To investigate the incidence status of viruses in major cultivated areas of watermelon and melon in Chungbuk Province, samples were collected from 2020 to 2021 in vinyl greenhouse of Jincheon and Eumseong and examined for virus infection using reverse transcription polymerase chain reaction. Of the six viruses on watermelon that was analyzed in this study, watermelons were infected with cucumber mosaic virus (CMV), watermelon mosaic virus (WMV), cucumber green mottle mosaic virus (CGMMV), and cucurbit aphid-borne yellows virus (CABYV). The incidence rate of CMV was 20.9-35.0%, WMV 0.4-15.8%, CGMMV 1.6-38.5%, and CABYV was 3.5-3.7% from 2020 to 2021. But strangely, there were no incidence of zucchini yellow mosaic virus and cucurbit chlorotic yellows virus (CCYV) during investigation. From this result, we knew the major virus was CGMMV on watermelon in Chungbuk Province. Molecular diagnosis assays of the two melon viruses, showed that melons were infected with CABYV and CCYV from 2020 to 2021. The incidence rate of CABYV was 53.9-92.2% and CCYV was 2.7-20.8%. The incidence of CABYV was high in melon cultivation of Jincheon and Eumseong, Chungbuk. Afterwards, it is necessary to establish a control management strategy for reduce the incidence of CABYV. Furthermore, we must pay attention that of CCYV even if the incidence was low.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.215-225
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• 2013

To assess the efficacy of nematicides for the control of plant-parasitic nematodes in fruit and vegetables fields, soil samples were collected from a cucumber field at Gongju; from strawberry fields at Buyeo, Nonsan, and Jinju; and from a melon field at Gocksung in Jeonnam Province, Korea. Plant-parasitic nematodes were separated from each soil sample and identified. The susceptibilities of the nematodes to abamectin 1.68% SC, cadusafos 3% GR, dazomet 98% GR, fosthiazate 30% SL and BA12011 SL were examined under laboratory and field conditions. The average population density of plant-parasitic nematodes was generally reduced after the treatment with nematicides; however, there was increase in the population of Pratylenchus spp. in soil after treatment with fosthiazate at Buyeo and Gocksung. Furthermore, there were increased populations following treatment with abamectin, cadusafos, and dazomet at Gocksung. The control effects of BA12011 treatment on plant-parasitic nematodes were confirmed to be similar to those of the other 4 nematicides evaluated, although its control effect was higher than that of fosthiazate in cucumber-growing soil at Gongju. The effects of nematicide treatment on egg mass formation in each of the collected soils differed according to the region of soil origin. Abamectin was effective in reducing the degree of egg mass formation in Buyeo and Jinju soil, whereas BA12011 was effective in Nonsan and Gocksung soil. Dazomet was found to inhibit egg mass formation in Gongju soil. To evaluate the effect of the newly developed nematicide, BA12011, experiments were conducted in a cucumber-growing greenhouse. The average population densities of Meloidogyne spp., Pratylenchus spp., and Helicotylenchus spp. after the first treatment were reduced to a greater extent than after the second treatment. It is thus suggested that early nematicide treatment is important for effective control of plant-parasitic nematodes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.63-69
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• 2015

This study was conducted to measure the effect of PE film mulching and irrigation methods on the growth, yield and antioxidant activity of potatoes tubers, in order to examine the possibility of cultivating potatoes in winter season in vinyl greenhouse on the reclaimed tidal land with weak ground inside the sea wall currently completed. The test was conducted on the sandy loam soil (Munpo series), and its salt concentration was 0.42% at the time of planting. The emergence speed per kind of PE film mulching was in the order of black > coloration > transparent > green color, with the black color showing the fastest speed. The temperature change during a day per kind of PE film mulching was in the order of transparent > coloration > green > black color. As for the salt concentration in the soil for each different way of water management, the salt concentration in the treatment of drip irrigation with 1 week interval was lower than that drip irrigation with 2 weeks interval. As for the growth of above-aerial part, plant length was higher, number of tiller and leaves were more and dry weight of above-aerial part was larger in the treatment of drip irrigaton with 1 week interval than drip irrigation with 2 weeks interval. As for the yield of potatoes depending on each way of water management, the yield in the treatment of drip irrigation with 1 week interval was more than drip irrigation with 2 weeks interval. The yield for each different kind of PE film mulching in the weekly drip-irrigation management section was in the order of transparent ${\geq}$ black ${\geq}$ coloration ${\geq}$ green color. In both of total phenol content and DPPH free radical activity experiments, the content and activity were higher with pear color vinyl treatment.

• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.22-28
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• 2005

The use of blankets to preserve heat in oriental melon cultivation is a common practise without artificial heating and warming systems. Efficiency of blanket decreased with annually usage. This experiment was conducted to investigate the effect of double layer nonwoven fabrics on heat conservation, plant growth, fruit quality and yield of oriental melon in greenhouse. The results were compared among the non-woven fabrics of 9+3, 6+6, 6+3 and 12 ounce from transplanting to April 20, 2001, 2002. Night temperature within tunnel was high at 9+3, 6+6, 6+3 and 12 ounce in order. In plant growth, stem length, leaf numbers and exudate, under double layer nonwoven fabrics were better than single layer blanket of 12 ounce especially, 9+3 double layer blanket was the best. Fruit weight, flesh thickness, soluble solid and marketable yield rate remained same in all treatments. Fermented fruit rate was the highest in 12 ounce as $32.9\%,\;19.6\%\;under\;9+3,\;17.1\%\;under\;6+6,\;16.6\%$ under 6+3 double layer nonwoven fabric, respectively. Compared to 2,260kg yield per 10a of 12 ounce single layer nonwoven fabrics, $7\%$ was increased under 9+3 but $3\%\;and\;13\%$ were decreased under 6+6 and 6+3 double layer nonwoven fabrics, respectively. Compared to income, 4,499-thousand-won per 10a, of 12 ounce single layer blanket, $13\%\;and\;3$ were increased under 9+3 and 6+6 double layer nonwoven fabrics, respectively. Whereas, $10\%$ decreased under 6+3 double layer nonwoven fabrics. From this results it is evident that 9+3 double layer nonwoven fabrics was the best for thermokeeping, fruit quality, and was most economic under non heating system.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.148-154
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• 1994

As a vegetative propagation method for ash species, which is a dioecism and a long cycle of fructification, cut-stem was soaked in water to induce adventitious sprouts, and 2-year-old ash seedling was cut in a nursery to induce adventitious sprouts. We obtained the 1,019 adventitious sprouts from branches of 101 plus trees througout the country. The mean ortet-age is 48. There is not a correlation between ortet ages and production of adventitious sprouts. These sprouts were placed in a cutting bed for rooting. Root ability varied with environmental factors of cuttings. The best rooting(87%) resulted from cutting performed in a vinyl-plastic greenhouse. Rooting was better on perlite+peat moss(2 : 1) medium than other media tested. The rooting ability was generally higher in 2-year-old ortet than plus tree ortet. In the root development of cuttings the non-container cuttings was better than container cuttings.