• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.67-81
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• 2020

The physicochemical parameters of honey are used to determine the botanic origin of honey and to specify the composition criteria for honey in regulations and standards. The parameters of honeydew and blossom honeys from Korean beekeepers were determined to investigate whether they complied with the composition criteria for honey in the food code legislated by Korean authority and to establish the parameters which should be subjected to principal component analysis for improved differentiation of honeys. The fructose and glucose contents of the honeydew honey did not comply with the composition criteria. The ash content of the honey was closely correlated with CIE a^* and CIE L^* The principal component analysis of fructose to glucose ratio, CIE a^*, CIE L^*, ash content, free acidity, and fructose and glucose contents enabled classification of honeydew, chestnut, multifloral, and acacia honeys. Additional advantage of the principal component analysis (PCA) is that the physicochemical parameters, such as fructose to glucose ratio (F/G) and color, can be determined using the analytical instruments for composition criteria and quality control of honey. This study suggested that composition criteria for honeydew honey should be established in the food code in accordance with international standards. The principal component analysis reported in this study resulted in improved classification of the honeys from Korean beekeepers.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.669-673
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• 2022

To evaluate biological activity of honeydew honey produced by Apis mellifera L. in Korea, we measured antioxidant activity by using DPPH (1,1-diphenyl-2-picryl hydrazyl), ABTS [2,2-azobis(3-ethylbenzothiazoline-6-sulfonate)], FRAP (Ferric reducing antioxidant power), and total polyphenol content assays. Korean honeydew honey respectively scavenged 26% and 86% of DPPH and ABTS radicals at the highest concentration of 10 mg/mL. In the result of FRAP assay, Korean honeydew honey showed activity (126 µM of FRAP value) to reduce Fe³⁺ to Fe²⁺. Total polyphenol content was 73.41 mg GAE/kg. Korean honeydew honey exhibited excellent antioxidant activity due to having high radicals scavenging ability and reducing power of ferric ion as well as the presence of phenolic compounds. These findings suggest that Korean honeydew honey has great potential as a functional food material.

• Korean journal of applied entomology
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• v.27 no.2
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• pp.63-67
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• 1988

Biotypes of the brown planthopper(BPH), Nilaparvata lugens St l, population migrated from maninand China in to southern coastal regions of Korea were investigated in 1985-1987 by honeydew excretion test using Korean cultvars,, 'Milyang 23'(no resistant gene), 'Cheongcheo-ngboy'(bph 1 gene), 'Milyang 63'(bph 2 gene) and 'Gayabyeo'(bph 1 and bph 2 gene). There was a correlation between the amount of honeydew excreted and the ability of each biotype to infest resistant cultivars: 'Milyang 23' with no resistant gene was highiy susceptible to bioty-pe-1, 2 and 3 ; 'cheongcheongbyeo' with resistant bph 1 was susceptible to biotype-2: and 'Milyang 63' with resistant bph 2 gene was highiy resistant to biotype-1, 2 and 3. Percent biotype dis-tribution of the female BPH collected in the southern coastal regions of Korea showed that in 1985, 1986 and 1987, the BPH biotype-1 was predominant accounting for 64.7%, 61.2% and 57.9%, respectivley, whereas bitype-2 was 22.0%, 21.9% and 29.7%, and biotype-3 was 13.3%, 17.0% and 12.6%, repestively.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.177-187
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• 2005

For the comparison of feeding behavior of Nilaparvata lugens among different rice varieties, electrical penetration graph (EPG) technique was used. Ten rice varieties were selected from national-widely recommended rice varieties cultivating in Chungnam province. The correlation between feeding duration and honeydew amount excreted was investigated, and the types of EPG pattern were analyzed among rice varieties. The EPG patterns divided into 6 types according to electrical specific feature, respectively. Type 1 pattern was a searching feeding sites, resting or wandering on a rice plant. Type 2 pattern was appeared when the insect untaken from phloem sieve element. Type 3 pattern was observed when the insect piercing into the rice plant. Type 4 pattern was observed when the insect salivating in rice plant. Type 5 pattern was observed when the insect ingesting from the xylem. Type 6 pattern was observed when the stylet moving in cell. Feeding duration time on Gum-nam was significantly shorter than Dong-jin, Dae-ahn, Dong-ahn, Dae-san. Also, on Gun-nam, it was shown that the brown planthopper did not penetrate the cuticle for a long time. The total number of excreted honeydew droplets by the brown planthopper was the greatest in Dong-jin variety and the least in Gum-nam variety. In proportion to phloem feeding time, the number of honeydew droplets had been increased. According to the results of EPG patterns and honeydew droplets analysis, N. lugens seems to prefer Dong-jin, Dong-ahn, Dae-san, and Dae-ahn to Gum-nam, Da-san, and Nam-chun rice plant variety.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2003.10a
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• pp.56-56
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• 2003

• Korean journal of applied entomology
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• v.34 no.1
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• pp.1-8
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• 1995

The relationships between aphids, plants, other organisms and some physical components of the environment are reviewed. Aspects considered include year cycles, polymorphism fecundity, relationship of different groups of aphids with particular groups of plants, honeydew, alarm pheromones, aposematic colouring, camouflage, colour variation within species, morphological variation within species, multivariate analysis and problems of its interpretation, parasitism, stridulating mechanisms, predators, coevolution of plants and aphids, plant galls, trapping aphids and the interpretation of trap catches, an curation of aphid collections. References are given to sources of information about aphids, with special reference to the Korean fauna.

• Journal of Life Science
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• v.9 no.2
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• pp.121-126
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• 1999

Some attempts were made to investigate the honeydew excretion of the brown planthopper(BPH), Nilaparvata lugens Stal, biotypes in terms of instal nymph, days after emergence, macropterous and brachypterous mated and unmated female, and macropterous female with different sources fed on 60-day-old rice cultivars with different resistance genes. The feeding amount of the BPH biotypes was measured by using the honeydew excretion test. The feeding amount of fifth instar on Miryang 23 with no resistance gene was higher than that of Cheon-gcheongbyeo with Bph-1 gene by two times. Macropterous and brachypterous females showed low feeding amount at first day after emergence, but they showed high feeding amount from second days after emergence. Also the feeding amount of brachypterous female was higher than that of macropterous female. In addition, the feeding amount of BPH was in the order of nymph

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.203-205
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• 2003

Black sooty mould fungus was observed on the upper side of the mulberry leaves caused by the Capnodium sp. This fungus develops with the utilization of the honeydew dropped by the whiteflies. Few selected insecticides like Monocrotophos, Chloropyriphos and Nuvan were tried to control the whitefly incidence and followed by the application of Maida (wheat flour paste) and Starch solution separately to control the incidence of the Capnodium on mulberry. It is found that a significant control of the whitefly incidence with the application of Nuvan (2 $m\ell$/L) and followed by Chloropyriphos (2 $m\ell$/L) and Monocrotophos (1.6 $m\ell$/L) and also a significant control of sooty mould infection were recorded with Starch and Maida application.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.193-199
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• 2008

Fifty potato cultivars were screened for potato aphid, Macrosiphum euphorbiae Thomas infestation degree in the field. Aphid honey dew secretion and contents of foliar substances(glycoalkaloids, total nitrogen, Ca, K and Mg) of the cultivars were measured in the laboratory to analyze the correlation between infestation degrees and those factors. The number of aphids ranged from 4.1 to 31.4 per five leaves. The lower density(less than 5 aphids) was found on cvs. Jidose, Recent, and Sebago. The aphid secreted highest(40.3 droplets) and lowest(15.7 droplets) honeydew on cvs. Jopoong and Anco, respectively. Degree of infestation is positively correlated to glycoalkaloids and total nitrogen contents of the potato leaf.