• Journal of Bio-Environment Control
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• v.7 no.4
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• pp.276-282
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• 1998

This experiment was carried out to elucidate the effect of ethychlozate foliar application on the fruit quality of Miyagawa Early Satsuma Mandarin in the plastic house. Ethychlozate(100mg.L$^{-1}$ ) was applied to the fruit at 100, 115 and 145 days after full bloom stage. The fruit was divided into four frequency level groups, with the control group receiving no Ethychlozate treatment and the level 3 group receiving all three applications. Peel coloration by a value Increased as application frequency increased. The a/b value trend was seen to be similar to this, but the b value ran contrary to the a value trend. Glucose contents of the fruit juice did not differ statistically among the application frequency levels but the fructose level was seen to be higher with increasing application frequency. Sucrose showed a similar trend to fructose in that it had a tendency to increase as application frequency increased. As a result of this, total sugar increased naturally with application frequency. The average Brix level among all treatment groups was higher than the average Brix level in the control group but Brix level did not differ significantly among application frequency levels. Acidity had a tendency to increase as application frequency increase, but there was no statistical difference found.

• Research in Plant Disease
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• v.19 no.1
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• pp.1-6
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• 2013

Optimal spray time, interval and number of preventive fungicides against fruit rots of kiwifruit were investigated at the orchard which both green kiwifruit cultivar 'Hayward' and gold kiwifruit cultivar 'Hort16A' are cultivating side by side during 2009 and 2010 growing seasons in Jeju island, Korea. The highest control efficiency was obtained from benomyl WP and followed by thiophanate-methyl WP and carbendazim+diethofencarb WP. The control efficacies of the fungicides were much higher when applied onto the kiwifruit canopy after the flowering time than before the flowering time but thereafter their control efficiencies were decreased drastically according to delays of spray timing. With increasing spray numbers of the fungicides, the control efficacy increased. However, optimal spray time, interval and number of the preventive fungicides for the effective control of fruit rots of kiwifruit were determined as 4 time-spray schedule with 2-week-interval just after the flowering time on both 'Hayward' and 'Hort16A' cultivars.

• Journal of Practical Agriculture & Fisheries Research
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• v.14 no.1
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• pp.47-59
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• 2012

The effects of organic calcium compounds (ACa) tree-spray for late growing stage on the mineral nutrition concentration of fruit, russet and quality in 'Fuji' apple were investigated. Optimum spray concentration of leaves by ACa tree-spray during late growth stage were ranged 125 times among 1,000 times. Also, Optimum concentration of fruits was effected to 125 times. Optimum spray times of leaves effected by ACa 500 times tree-spray during late growth stage were effective in one times (Sept. 25) and three times (Sept. 25, Oct. 5, 15). Also, Optimum times concentration of fruit skin was effected to one times (Sept. 25) and fruit flesh was effected two times (Sept. 25, Oct. 5) and three times (Sept. 25, Oct. 5, 15). Phytotoxicity by tree-spray of ACa concentration and times different not occur to leaf and fruit.

• Korean Journal of Organic Agriculture
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• v.15 no.1
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• pp.109-121
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• 2007

For developing standard method for diease, pest and weed control in environmental friendly 'Ssam' vegetable cultivation, this study was carried out to investigating agriculture material use in organic agriculture and no pesticide cultivation for lettuce, kale, leafy perilla and korean cabbage. The 28.6% of investigated farmer carried out seed sterilization by seed selection with salt solution and soaking in chitosan that not validated. For raising seedling periods, the 55.6% of farmer did not use environmental-friendly agriculture material for, diease control and the 50% of farmer used one time for. pest control. Therefore, the control of disease and pest could be achieved with one or two times use of environmental-friendly agriculture material. Seed sterilization was carried out by soil solar sterilization, one time per year in 71.4% of farmer. Weed was controled by black PE film for weed germination of furrow in many farmer, by man-power weeding for weed of ridge in 85% of farmer and by machine weeding and mulching in some farmer. During cultivation period, the major pest were Aphis gossypii in lettuce, Plutella xylostella in kale, Plutella xylostella and Phyllotreta striolata (Fabricius) in korean cabbage and Pyrausta panopealis (Walke) in feat perilla. The many farmers used environ-mental-friendly agriculture material for control of pest over 10 times for spring season, and more used sold materials in market than home-made materials. In result, it needs to develop standardized method and validate cultivation methods for control of disease and pest, and seed sterilization treatment environmental-friendly 'Ssam' vegetable.

• Research in Plant Disease
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• v.26 no.4
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• pp.229-238
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• 2020

Field validation of PBcast, an infection risk model for Phytophthora blight of pepper, was conducted through a designed field experiment in 2012 and 2013. Conduciveness of weather conditions at 26 locations in Korea in 2014-2017 was also evaluated using PBcast. The PBcast estimated daily infection risk (IR) of Phytophthora capsici based on weather and soil texture data. In the designed filed experiment, four treatments including routine sprays at 7-day intervals (RTN7), forecast-based sprays when IR reached 200 (IR200) and 224 (IR224), and no spray (CTRL) were compared in terms of disease incidence and number of sprays recommended for disease control. In 2012, IR had reached over 200 twice, but never reached 224. In 2013, IR had reached over 200 three times and once higher than 224. The RTN7 plots were sprayed 17 and 18 times in 2012 and 2013, respectively. Weather conditions throughout the country were generally conducive for Phytophthora blight and 3-4 times of fungicide sprays would have been reduced if the PBcast forecast information was adopted in the decision-making for fungicide sprays. In conclusion, the PBcast forecast would be useful to reduce fungicide applications without losing the disease control efficacy to protect pepper crop from Phytophthora blight.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1295-1299
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• 2011

This study was conducted at the organic farming fields which garlics were planted. The treatments were as follows; water of $3,850L\;ha^{-1}$ (Control), plots applied 1 time, 2 times and 3 times with sea water of $3,850L\;ha^{-1}$. In 3 times sea water treatment plot, the level of EC, Exch. Na and $Cl^-$ were 1.1, 2.1, and 3.3 times higher than control plot, respectively. Due to seawater application, the contents of inorganic elements such as T-N, Ca, Mg, Na, Fe, Mn, and Zn in garlic were generally lower than Control, but not significant.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2004.03a
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• pp.220-223
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• 2004

• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.130-138
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• 1998

This experiment was conducted to study the effect of ethephon(100mg.L$^{-1}$ ) and calcium carbonate (10000mg.L$^{-1}$ ) on the acceleration of peel coloration of ‘Miyagawa Early’ Satsuma Mandarin in the plastic house. The foliar application treatments were conducted once. twice or 3 time at intervals of 15 days from degreening of the fruit apex. Peel coloration of a value by spraying ethephon ＋ clef-non was increased with treatment frequency. The a/b values ran similar to this trend. As a result of this, peel coloration was accelerated by foliar application of ethephon ＋ clef-non. Glucose and fructose did not differ significantly among foliar application frequencies. Sucrose and total sugar increased as foliar application frequency increased, but there was no significant di(ference among foliar application frequency group. The brix values were higher than 12˚BX in all treatments. However, a distinct difference between the control Brix value and the values for the treatment groups was found only in the level 3 frequency group.

• Research in Plant Disease
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• v.7 no.1
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• pp.37-41
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• 2001

This experiment was carried out to investigate the prevention of bacterial shot hole by Bordeaux mixture when it was sprayed on peach trees after harvest. bordeaux mixture was sprayed on \`Mibaeko\` peach trees 1 to 3 times after mid September, and the occurrence of bacterial shot hole was examined in the next year. Bacterial shot hole in leaves appeared from mid May and thereafter increased gradually. The more times was sprayed Bordeaux mixture, the less peaches were diseased with bacterial shot hole. At the beginning of August, the peach harvest time, the disease incidence of the untreated control plot was 27.4 to 38.1%, while the disease incidence was 9.7 to 31.8% when Bordeaux mixture was sprayed. The control value ranged from 16.5 to 64.6%. Occurrence of the fruit disease was similar to that of the leaf disease. Incidence of the fruit disease in the untreated control was 17.2 to 21.6%, but incase of the chemical treatment, it was 5.0 to 12.2 %, showing 41.9 to 70.9% of the control value. Chemical injury on peach leaves were not found in the 4-12 and 408 types, but occurred in some degrees in the 6-6 type of Bordeaux mixture.

• Journal of Korean Society of Forest Science
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• v.94 no.4 s.161
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• pp.277-280
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• 2005

In order to prevent chestnuts from damage by the peach pyralid moth, Dichocrosis punctiferalis, a sprinkler system was installed on the chestnut orchard. Such a test was conducted at Yeoju-gun, Gyeonggi-do, Korea in 2002. Insecticides of fenitrothion 50% EC, x1,000 and diflubenzuron 25% Wp, x2,500 were sprayed at ten-day fifteen-day and twenty-day intervals during the period of D. punctiferalis adult occurrence by sprinkler system. The peach pyralid moths generally emerged for about 60 days from early July to early September, and peak emergence was 10 days from late July to early August. Damage rate of chestnuts were 0.9-4.0% on average with this crown insecticide spraying with diflubenzuron, while 30.4% when not treated. Control effectiveness of this insecticide spraying was 92%(86.7-97.0%). In conclusion, effectual times and number of insecticide application with sprinkle system against peach pyralid moth were from early July to late August and four or five times at ten or fifteen day intervals, respectively.