• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.73-77
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• 2016

In this study, we examined the changes of fruit number and fruit weight according to the length of bearing branch of Actinidia arguta and identified the correlation the length of bearing branch and fruit characteristics. The fruit weight and the fruit number of A. arguta bearing branch which length are below 15 cm and over 30 cm were 11.7 g, 4.3 and 12.3 g, 13.8, respectively. From the results, the bearing brach which length was below 15 cm must be removed in winter season pruning. The pruning experiment was conducted to examine the effects on fruit quality and yield of A. arguta. Total fruit yield of heavy-pruning was $14.3{\pm}1.5kg/tree$. The production of fruits over 15 g wight was $8.2{\pm}0.9kg/tree$, that of fruits between 10 g to 15 g was $4.0{\pm}0.7kg/tree$, and that of fruit below 10 g was $2.1{\pm}0.3kg/tree$, respectively. Average fruit yield of nonpruning was $26.7{\pm}2.1kg/tree$, fruit yield over 15 g, between 10 g and 15 g, and below 10 g were $2.5{\pm}0.5kg/tree$, $19.2{\pm}1.4kg/tree$, and $5.0{\pm}0.6kg/tree$, respectively. Distribution of high quality fruit (over 15 g) showed that non-pruning was almost 15~16 g but pruning was evenly distributed between 15 g and 20 g. According to the survey, The high quality fruit (over 15 g) would not be harvested if the winter pruning is not applied in the A. arguta cultivation.

• Korean journal of applied entomology
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• v.54 no.3
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• pp.191-197
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• 2015

Fruit drop due to Eurytoma maslovskii infestations of Japanese apricot (Prunus mume) is a serious economic issue in most parts of Jeonnam Province, with the exception of the coastal areas such as Wando, Shinan, Yeosu, and Muan. The average incidence of fruit drop was 67% in 2013 and 33.3% in 2014. E. maslovskii larvae overwinter inside the pits of Japanese apricots. Larval survival rates decrease to less than 30% after a rainy summer season. The eggs are long oval of 0.68 mm, 0.29 mm and ivory white. Mature larva is of 6.56 mm, 3.18 mm. Free pupa are black, adult females and males of 6.97 mm, 4.90 mm lengths, respectively, while the ovipositor is 0.64 mm in length. Adult emergence occurs from early April to early May, when Japanese apricot fruits are from 4 mm to 17 mm in diameter. Adults persist for 13.5 d after emergence, and the sex ratio of females to males was found th be 45.9:54.1. Although up to four eggs may be oviposited per fruit, only one larva will ultimately survive, ans the larvae are cannibalistic. The period during which E. maslovskii is able to oviposit on Japanese apricots only lasts from mid- to late April (fruit diameter: 12~16 mm). When the diameter of the fruit is >16 mm, the pit of the Japanese apricot hardens and larvae have difficultly penetrating the stone. Therefore, the most effective method of controlling this pest is to spray orchards with a control agent 2~3 times, at 5 d intervals, beginning in mid- April.

• Korean Journal of Plant Resources
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• v.37 no.4
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• pp.386-391
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• 2024

'Jinha' is a new strawberry (Fragaria × ananassa Duch.) cultivar, which was released by the Highland Agriculture Research Institute in 2019. The 'Jinha' cultivar originates from a 2011 cross between 'Albion' and 'Goha,' both of which exhibited excellent ever-bearing characteristics, including continuous flowering and large fruits under long-day and high temperature conditions. This new cultivar was initially named 'Saebong No. 11' after examining its characteristics and productivity during summer cultivation between 2012 and 2016. After regional adaptability tests, 'Jinha' was selected from 'Saebong No. 11' as an elite cultivar. The general characteristics of 'Jinha' include intermediate, elliptic leaves, and medium growth. The fruits are conical and of a red color. The plant height of 'Jinha' is simiar to that of the control variety, 'Flamenco', but it has a lot of number of leaves. The cluster length of 'Jinha' was 35.5 cm, 10.8 cm longer than 24.7 cm of the control variety. The number of flower clusters of 'Jinha' appeared 14.4, which was 4.1 more than that of 'Flamenco'. The average fruit weight of 'Jinha' was 10.1 g, which was 0.8 g heavier than that of 'Flamenco'. The soluble solid content of 'Jinha' was 10.2 °Brix, which was 2.0 °Brix higher than that of 'Flamenco'. The marketable yield of 'Jinha' was 25,931 kg·ha^-1, 440% more than that of 'Flamenco' with 5,900 kg·ha^-1. Therefore, the new cultivar of ever-bearing strawberry 'Jinha' is expected to be very popular in the export or bakery market because it is high soluble solid content and good shape.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.135-145
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• 2009

This research was conducted to investigate the effect of various phosphorus concentrations in fertilizer solution on growth of and nutrient uptake by 'Chugyang' egg plant (Solanum melongena L.). Tissue and soil analyses were also conducted to set the threshold levels of phosphorus in plants when disorders develop for phosphorus deficiency or excess. Brown and purple areas developed on the margin of mature leaves and it enlarged rapidly in P deficient plants. The fruits in P deficient plants were small and dull purple in color. When P were excess in fertigation solution, the margins of lower leaves became scorched and it enlarged to inner part of the leaves. The fruits of P excess plants became small and had the curl shape. The tissue $PO_4$-P contents in the most recently fully expanded leaves and dry weight of full above ground plant tissue at 35 days after transplanting showed quadratic response ($y=0.7887+0.2394x-0.0197x^2$) and cubic response ($y=10.43+14.47x-4.7642x^2+0.3977x^3$) to elevated $PO_4$-P concentrations, respectively. When 10% reduction in dry weight set to threshold levels, optimum tissue $PO_4$-P contents are between 0.98 to 1.35%. The yield determined at 150 days after transplanting also showed cubic response to elevated phosphorus concentrations in fertigation solution ($y=1194.6+1502.2x-454.5x^2+35.64x^3$). When the 10% reduction in yield is set to threshold levels, the tissue $PO_4$-P contents for maximum yield should be around 1.53% to 2.25% in most recently fully expanded leaves at 150 days after transplanting.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.224-230
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• 2013

BACKGROUND: Perchlorate(${ClO_4}^-$) is an anion that is extremely water-soluble and environmentally stable. It mostly exists in the form of sodium perchlorate, ammonium perchlorate and potassium perchlorate which are used in rocket fuels, propellants, ignitable sources, air bag inflation systems and explosives. Perchlorate can be taken into the thyroid glands and interfere with iodide uptake. The determination of perchlorate in agricultural products is important due to its potential health impact on humans. The objective of this study was to determine the perchlorate concentrations in the samples of various agricultural products and soils. METHODS AND RESULTS: In this study, samples of cereal(Rice, Barley, Corn, Bean), vegetable(Spinach, Lettuce, Sesame, Chives, Chili, Pumpkin, Tomato), fruit(Apple, Pear, Tangerine, Grape) were analyzed for perchlorate contents. Perchlorate concentrations were analyzed by liquid chromatography-tandem mass spectrometry. The results showed that agricultural products respectively contained perchlorate concentrations in the range of : cereals N.D.~$7.46{\mu}g/kg$, vegetables $0.52{\sim}23.06{\mu}g/kg$, fruits $0.19{\sim}2.66{\mu}g/kg$. Bioconcentration factor was in the order of : vegetables > cereals > fruits. Bioconcentration factor was highest follwed by Sesame 37.88, Corn 21.51, Spinach 10.57, Tangerine 4.39, Chives 2.89 and Lettuce 1.90. The recoveries of perchlorate from spiked agricultural products and soils ranged from 87.72~111.26% and 102.09~111.23%. CONCLUSION(S): The health risk assessment results obtained in this study are lower than the RfD(Reference Dose, 0.0007 mg/kg/body weight/day) value as suggested by the Integrated Risk Information System(US IRIS). Our results indicate that, people currently exposed to perchlorate from agricultural products consumption are considered as safe.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.242-256
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• 2012

QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method has been a lot of research for pesticide analysis, because it is very simple and fast. However, this method requires high sensitivity instrument such as LC-MS/MS because of the use of small sample volume and many impurities compared to the conventional method. So, QuEChERS method needs to be modified for using with HPLC and GC-ECD/NPD. The aim of this work was to study the application of the QuEChERS method as well as its modification for the extraction and preconcentration of 5 groups of 61 pesticides from 4 fruits prior to their determination by HPLC-PDA, GC-ECD/NPD, and LC-MS/MS. The method was validated using spiking levels at 0.1 mg/kg (or 0.01 mg/kg) in apple, grapes, pear and persimmon. The average recovery by QuEChERS AOAC Official 2007. 01 version using the LC-MS/MS varied from 71.1127.4% for 61 pesticides. The average recovery rates using modified QuEChERS varied from 70.9~126% for 61 pesticides by HPLC-PDA and GC-ECD/NPD. The results satisfied the criteria of multiple pesticide residue analysis, setting 70~130% for recovery rates and below 30% for CV.

• Journal of Food Hygiene and Safety
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• v.38 no.6
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• pp.489-495
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• 2023

In this study, we detected the presence of residual pesticides in 341 agricultural products collected from local food outlets in western Gyeonggi Province. Residual pesticides were detected in 105 (30.8%) samples. Six samples exceeded the legal limits for residual pesticides, resulting in a non-compliance rate of 1.8%, which was slightly higher than the average non-compliance rate of 1.4% in the last three years. Among the tested agricultural products, only fruits and vegetables were found to have pesticide residues, with 24 of 34 fruits (a detection rate of 70.6%) and 81 of 277 vegetables (a detection rate of 29.2%) testing positive. In total, 59 types of pesticides, including acetamiprid, which was detected 208 times, were detected and had a detection range of 0.01-2.38 mg/kg. Among the 105 agricultural products containing pesticide residues, a single pesticide was detected in 62 samples (59%) and two or more pesticides were detected in 43 samples (41%). In particular, 14 pesticides were detected in the same sample of peaches; dinotefuran was detected 21 times. Upon examining the toxicity of the detected pesticides, Class III pesticides (moderate toxicity) were detected 44 times (21.2%) and Class IV pesticides (low toxicity) were detected 164 times (78.8%). Class I, II, and III pesticides with fish toxicity were detected 68 (32.7%), 14 (6.7%), and 126 times (60.6%), respectively. Upon examining the exposure to high-frequency pesticide components detected five or more times, the hazard index was found to be ≤2.8%. Accordingly, the hazard of residual pesticides based on dietary intake was deemed insignificant.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.416-423
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• 2023

Figs has known to have antioxidant, whitening, anti-inflammatory, and antibacterial effects in their leaves, roots, stems, latex, and fruits. In order to develop cosmetic materials based on natural products, we have studied on the skin activity of the ficin in latex as well as the whitening function of the fruit extract with 70% ethanol, and used it as a raw material for released cosmetic product. However, there is little research on the demand for the development of new eutectic solvent extraction methods and its ability to control skin inflammation and psoriasis regulation. Thus, in this study, we evaluated the effectiveness of fig fruit extracts and fractions using eutectic solvent extraction for skin inflammation control and psoriasis. First, fig fruits were extracted under optimal eutectic solvent conditions and fractionated with n-hexane, dichloromethane, ethyl acetate, and butanol. First, the antioxidant activity and inhibition of nitric oxide (NO) production were confirmed in mouse macrophage RAW264.7 cells. In addition, as a result of observing the mRNA expression through RT-PCR, pro-inflammatory cytokines such as TNF-α, IL1α, and IL-1β were suppressed significantly in the hexane, dichloromethane, and ethyl acetate fractions. In addition, it was confirmed in TNF-α stimulated HaCaT keratinocyte model. Finally, chemokine CC motif ligand 20 (CCL20), marker gene of human psoriasis skin disease, was significantly suppressed in the hexane, dichloromethane, and ethyl acetate fractions. These results suggested its anti-inflammatory and skin soothing effect and the possibility of development as an excellent skin soothing natural cosmetic material in the future through future clinical trials.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.227-232
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• 2003

This study was conducted to evaluate the terminal residue of a new fungicide, KNF 1002, in cucumber and pepper under greenhouse and field conditions. When a microemulsion formulation (20%) of KNF 1002 was applied once or twice during $1{\sim}7$ days before harvest, its terminal residue in cucumber ranged <$0.02{\sim}0.20\;mg/kg$ under greenhouse condition. In pepper, its figure recorded $0.31{\sim}0.79\;mg/kg$ and $0.11{\sim}0.28\;mg/kg$ under greenhouse and field conditions, respectively. Much higher level of terminal residues was observed in leaves than those in fruits in pepper, showing $7.38{\sim}25.20\;mg/kg$ and $0.11{\sim}1.99\;mg/kg$ under greenhouse and field conditions, respectively. Cultivation condition affected evidently the residue level in pepper harvests. Residual pattern of KNF 1002 seemed to be comparable to strobilurin fungicides currently used.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.37-37
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• 2014

Glomerella leaf spot pathogens can infect apple leaves, causing extensive necrosis and premature defoliation, as well as necrotic spots on fruit. In recent years, the disease has been reported with increasing frequency in China, and appears to be spreading rapidly in some apple-producing areas. In this study, fungal isolates from diseased apples leaves collected in Henan and Shaanxi provinces were analyzed based on morphology, cultural characters, pathogenicity and molecular phylogenetics. It was found that Glomerella leaf spot of apple was caused by two pathogens, Colletotrichum fructicola and C. aenigma. Pathogenicity tests showed that C. fructicola and C. aenigma could infect apple leaves of cultivar Golden Delicious, as well as Gala, Qinguan, Pink Lady, Pacific Rose, Golden Century and Honeycrisp, all of which include Golden Delicious in their parentage. In wound inoculation experiments, C. fructicola and C. aenigma were pathogenic to fruit of Gala, Qinguan, Golden Delicious, Pacific Rose, Starkrimson and Fuji. With non-wounded fruit, C. fructicola was pathogenic to Gala and Golden Delicious, and C. aenigma was pathogenic to Gala. It is concluded that the two pathogens could be differentiated according to pathogenicity to leaves and fruits of different apple cultivars.