• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.897-909
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• 2015

This study was conducted to evaluate the effect of weed control on disease incidence, plant growth and fruit quality, and to provide effective method to farmers at the vineyard. At the raincoat greenhouse cultivating 'Campbell Early', several weed controlling methods were compared to the control. Mean temperature of plots between soil covering (C.B., W.F., S.N., P.F. and R.H.) and non soil covering (M.W.2, M.W.3 and U.T.) were similar with $26.2^{\circ}C$ (July) and $25.8^{\circ}C$ (Aug.), but humidity of soil covering was sharply decreased in late-July under 40%. Soil water were all higher in soil covering plots than that of non-soil covering, however, soil temperature was recorded lower in soil covering plots. Disease incidence of Peudocercospora vitis according to soil coverings had effect on black plastic film mulching by decreasing grapevine leaf spot to 85% in July, 69% in August, compared to the control, with showing the smallest lesion incidence in FMB. Among growth characters, internode length and internode width of black plastic film mulching was higher than that of the control. SPAD value of black plastic film mulching was recorded the highest. It was not significant among the treatments, but brix was recorded highly in black plastic film mulching with $14{\sim}15^{\circ}Brix$.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.440-445
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• 2010

This study was carried out to investigate the toxicities of five registered insecticides to the Lycorma delicatula nymphs and adults. Insecticidal activities were evaluated by testing systemic and residual effects in the laboratory, and control efficacy in the vineyard. For the 3rd nymphal instars and adults, etofenprox+diazinon, chlorpyrifos, etofenprox, dinotefuran and imidacloprid showed perfect insecticidal activity. The systemic effects of dinotefuran and etofenprox+diazinon on grape roots at half concentration were showed the adult mortality of 82.2% and 84.4%, respectively. Chlorpyrifos at recommended concentration was showed mortality of 86.0%. The leaf systemic effects at recommended and half concentrations of all insecticides except dinotefuran were lower than 65% but the mortality at double concentration of chlorpyrifos, dinotefuran, etofenprox were more than 82%. The residual effect between etofenprox+diazinon and dinotefuran at recommended and double concentrations were 100% at 14 days after treatment, the other insecticides have low efficacy. All the four insecticides showed 87% control value on nymphs in the field test and adults appeared more than 96% control value st and adinotefuran, etofenprox+diazinon, however, the other insecticides decreased to 59.1 % and 61.2%. Therefore, dinotefuran and etofenprox+diazinon showing high systemic effects to roots and long residual effects to leafs have high control efficacies.

• Research in Plant Disease
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• v.15 no.3
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• pp.193-197
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• 2009

Pseudocercospora leaf spot was major disease of grape cultivar 'Campbell Early' in Korea. Leaf spot first appeared in early June and rapidly dispersed to other leaves through rainy season. Disease progress of leaf spot by Pseudocercospora vitis in plastic green house, in the two provinces (Gimje and Gimcheon), were investigated in 2007. Differences of Infected leaves (%) between cultivation systems were observed in field and plastic green house, but there was no difference between provinces. Micro environmental factors, such as temperature and relative humidity, were correlated with infected leaves by PROC REG procedure of SAS (Statistical Analysis System). As a result, regression model best described ($R^2=0.95^{**}$) the infected leaves as a function of the interaction of cumulated temperatures; Y (Infected leaves)=-7.0101+0.0496$\times$20Hcum (Cumulated hour above 20 degree)+0.0208$\times$20cum (Cumulated temperature above 20 degree)-0.2781$\times$25Hcum (Cumulated hour above 25 degree). A statistics model was shown that cumulated hour and temperature above specific degree were critical factor for Pseudocercospora leaf spot on the grapevine leaves in plastic green house.

• Agribusiness and Information Management
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• v.6 no.1
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• pp.1-11
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• 2014

The purpose of this study is to develop the growth prediction model that can predict growth and development information influencing on the production of citrus fruits. The growth model was developed to predict the floral leaf ratio, number of fruit sets, fruit width, and overweight fruits depending on the main period of growth and development by considering the weather factors because the fruit production is influenced by weather depending on the growth and development period. To predict the outdoor-grown citrus fruit production, the investigation result for the standard farms is used as the basic data; in this study, we also understood that the influence of weather factors on the citrus fruit production based on the data from 2004 to 2013 of the outdoor-grown citrus fruit observation report in which the standard farms were targeted by the Agricultural Research Service and suggested the growth and development information prediction model with the weather information as an independent variable to build the observation model. The growth and development model for outdoor-grown citrus fruits was assumed by using the Ordinary Least Square method (OLS), and the developed growth prediction model can make a prediction in advance with the weather factors prior to the observation investigation for the citrus fruit production. To predict the growth and development information of the production of citrus fruits having a great ripple effect as a representative crop in Jeju agriculture, the prediction result regarding the production applying the weather factors depending on growth and development period could be applied usefully.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.230-234
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• 2011

While preparing a floristic study of Korean hepatics, we discovered the 4 unrecorded species Alobiellopsis parvifolius, Calypogeia japonica, Hattoria yakushimensis and Nardia subclavata. A. parvifolius is often confused with Solenostoma fusiforme (Steph.) Amak. in appearance, but the former differs by occasional presence of underleaves and a large hyaline outer cells of stem. C. japonica is similar to C. tosana (Steph.) Steph. The former, however, is separated from the latter by 2-3 biconcentric oil-bodies per cell compared to 3-5 grape oil-bodies per cell. H. yakushimensis is a monotypic genus based on a Japanese species. This genus is characterized by unlobed, closely imbricate leaves with margins distinctly incurved and usually pigmented with a reddish purple color. N. subclavata is similar to N. assamica (Mitt.) Amakawa in large underleaves and globular oil-bodies. The former, however, is separated from the latter by convex trigones versus concave trigones, smooth cuticles versus smooth to verrucose cuticles, and oil-bodies occurring in each cell versus occurring in approximately half or fewer leaf cells.

• Korean Journal of Organic Agriculture
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• v.19 no.4
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• pp.529-541
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• 2011

Bordeaux mixture made with each grade of lime and copper sulfate was tested general property and disease control value. Bordeaux mixture was made by composition of each grade of lime (95%, 80%) with each grade of copper sulfate(98.5%, 95%). Phytotoxicity was evaluated to Bordeaux mixture made with each grade of lime and copper sulfate, and then low grade copper sulfate (95%) was more severely in the grapevine leaf. Bordeaux mixture, made with each grade lime and copper sulfate, were tried to evaluate control effects of downy mildew in field. As a result, Bordeaux mixture (95% of lime and 98.5% of copper sulfate, 6-6) applied 5 times at late in June was showed more effective disease control value than any other trials of Bordeaux mixture. There was no difference in nutrient status of petiole each treatment. But fruit characteristics were shown more slightly improved quality.

• Research in Plant Disease
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• v.12 no.1
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• pp.15-19
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• 2006

This study was carried out to know pathogenicity of the pathogen isolated in several location of Korea and penetration mechanism of the Pseudocercospora vitis ($(L\acute{e}v)$.) Speg. Inoculation tests at room temperature were performed on both sides of leaves with different isolates of the fungus. The typical symptoms appeared on the abaxial leaf surface, but no symptom was observed on the adaxial leaf surface with all isolates. The average incubation period was nine days, since all symptoms appeared from 8 to 10 days after inoculation. In order to know the mechanism of invasion of P. vitis to grapevine, the behavior of penetration hyphae through stomata were compared in two cultivars having different level of resistance. In order to know the mechanism of resistance of grape vine to P.vitis, two cultivars having different level of resistance were compared by counting the numbers and measuring size of the stomata per leaf. In a susceptible cultivar Campbell Early, the number of stomata was more than that of a resistance cultivar 'Kyoho'. In a susceptible cultivar 'Campbell Early', the fungus entered readily into stomata after inoculation. However, in a resistant cultivar 'Kyoho', the fungus seemed to pass over or surrounded only the guard cells. In comparison of height of guard cells of stomata between the two cultivars, significant differences were observed by scanning electron microscopy and light microscopy. The height of guard cells of 'Campbell Early' showed a little higher than those of 'Kyoho' known to be resistant to the fungus.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.308-314
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• 2011

Efficient transformation and regeneration methods are a priority for successful application of genetic engineering to vegetative propagated plants such as grape. In this study, methods for Agrobacterium tumefaciens-mediated transformation and plant regeneration of grapevine (Vitis vinifera) were evaluated. Tamnara, Heukgoosul, Heukbosek, Rizamat were co-cultivated with Agrobacterium strains, LBA4404 containing the vector pBI121 carrying with CaMV 35S promoter, GUS gene as reporter gene and resistance to kanamycin as selective agent. Seven percent of the maximum regeneration frequency was obtained from co-cultivated with explants from Rizamat with LBA4404 strain on selection medium with kanamycin. The addition of acetosyringone, 200 ${\mu}m$ in virulence induction step was a key factor for successful GUS reporter gene expression in grapevine transformation. Transgenic plants showed resistance to kanamycin and the GUS positive response in leaf ($T_0$) stem ($T_0$) and petiole ($T_0$).

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.210-214
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• 1997

The experiment was conducted to obtain basic informations on the effects of key environments and fungicides on the sporulation, conidial germination and hitial growth of the hyphae of grape powdery mildew fungus Uncinula necator. Maximum sporulation occurred at RH 75~96% in vitro adiusted with sulfuric acid solution. Conidial germination and initial growth of the hyphae were better at 5% water agar than distilled water, and best at $26^{\circ}C$ and pH 5.0 of the substrates. Germination occurred equally well at light intensity of below 100 lux or dark condition, which was better at water agar supplemented with leaf extract 30% than pure water agar. The water agar supplemented with triazole fungicides reduced conidial germinations and initial growth of the hyphae signifcantly, in proportion to the increase in concentration of the fungicides, but the maguitude of reduction depended on the fungicides. Particularly in myclobutanil, reduction rate was very low as increased in concentration.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.15-23
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• 2016

A study was conducted to evaluate the effects of irrigation (amount, interval) on tree growth, fruit quality, and cracking of organic 'Campbell Early' grapevine in 2012 and 2013. Three irrigation treatments were applied using a sprinkler system from mid-June to mid-August in 2012 and 2013, as follows: 10 mm was applied daily (10 mm-IR), 20 mm was applied every two days (20 mm-IR), and 30 mm was applied every five days (30 mm-IR). Soil electrical conductivity (EC) and temperature were found to be greatest in the 10 mm-IR treatment in both years. Soil moisture content ranged between 20-40% in the 10 mm-IR, between 20-60% in the 20 mm-IR, and between 20-70% in the 30 mm-IR treatment plots. The total number of leaves per shoot and shoot growth were found to be greatest in the 20 mm-IR and 30 mm-IR treatments, respectively. Cluster and berry weights, and cluster and berry sizes were not consistently affected by the treatments. The 10 mm-IR treatment resulted in an increase in fruit SSC, SSC/acidity ratio, and berry skin pigmentation ($b^*$; blue). Approximately 5% of fruit cracking was observed on average over both years in the 10 mm-IR-treated fruit, while the 30 mm-IR treatment resulted in nearly 18% of cracking in 2012. Average marketable fruit yield per year over two years was greatest for the 10 mm-IR treatment ($24.4t{\cdot}ha^{-1}$) followed by the 30 mm-IR treatment ($22.7t{\cdot}ha^{-1}$) and lastly the 20 mm-IR treatment ($22.2t{\cdot}ha^{-1}$). Thus, the 10 mm-IR treatment represents a suitable irrigation regimen for controlling leaf and shoot growth of vines grown under a rain-shelter system in sandy loam soils, while improving fruit sugar contents and skin color and limiting fruit cracking.