• Journal of Sericultural and Entomological Science
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• v.13 no.2
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• pp.123-133
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• 1971

The author is the first man who tried to use an anesthetic on insect specially for silkworm in orde to evaluate the silkworm health and silk yielding ability and the obtained results are as followings. 1. The necessary ether vapor induction for narcosis on silkworms is varied by the glowth of the silkworm which the larger worm is, the longer induction is required. For instance, it was 2∼3 minutes for the worms of third day fifth instar silkworm in case use of ether anesthetic. 2. The longer anesthetic induction for silkworms, the longer recovery needs from anesthesia. In case five minutes ether vapor induction, silkworms recovered narcosis during in 5∼130 minutes which had varied very much by the health variation. 3. The ether induction caused silkworm to vomit digestive juice from a few per cent of the worms, but the chloroform induction showed majority of the worms to vomit the digestive juice out of mouth. So, the ether was found as better anesthetic for silkworms. 4. When ether induction last more than 20∼30 minutes, the recovered silkworms can eat mulberry, but when it gets more than three hours they can not eat mulberry. And when it last more than ten minutes, the silkworm may eat mulberry leaf, but they can not spinn cocoon properly. 5. In case five minutes ether induction for silkworms on third day fifth instar, the stronger variety is, the rallier recovered from narcosis. 6. The recovering duration from narcosis varies regarding with each worm health which shows Poisson′s distribution even in a same variety silkworm. 7. The female worms recover from narcosis earlier than male worms which means the female worm is stronger than male one. 8. The later recovered silkworm from narcosis spinned more rich cocoon silk and ended with smaller pupae weight. Such a tendency showed until at some recovery duration, then the silk yield droped down on the worms recovered in more longer duration. The author (Choe) had named such a relation curve as "Silk Yield Curve against Silkworm Health." 9. The silk yield or cocoon layer ratio had varied from 13 to 27% even in a same worm varity cocoon which showed serious variation and call attention carefulness for the duplication work of a variety silkworm eggs. 10. Not always the rich silk yielding worm is the best worm during the silkworm selection and it should be considered with the silkworm health evaluation. 11. At present situation, only specific breeding expert is allowed to join in the selection service because of need many years experience by use of visual observation, but the ether anesthesia method may help such an evaluation with more accuracy and easy way even for the people in fresh on the field. 12. The effect of the narcosis on the silkworm for the next generation or hybrid worm will be reported in next publication.

• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.38-47
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• 1986

Silkworm(Bombix mori) were reared with modified artificial diets which were mixed with, as additives, leaf powders of Erigeron canadensis L., Cassia tora L., Cyperus anuricus Var.Laxus and Vigna Sinensis NEDL. The effects of additives on silkworm characteristisc of tested plants were summarized as follows ; 1. About 2-5% addition on dry weight base of leaf powders of E. canadensis, C. tora, C. anuricus or V.sinensis to the basic artificial diet promoted feeding response and digestion and resulted in good practical silkworm characteristics. The addition of V.sinensis and C.anuricus showed especially good effects. 2. The syneristic effect between different plant species was not recognized based on the feeding response and digestion of silkworm reared with various combinations of 2-4 different plant additives. 3. Electrophoretic zymograms of estrase, protease and phosphatase on haemolymph, intestine and silkgland were significantly different among treatments. In general, 1 or 2 more electrophoretic bands were detected when feeding response and digestion were promoted. 4. Contents of starch, crude fat, crude protein and inorganic base were apparently higher in the tested plants than in mulberry leaves. However, no volatile ingredent which is directly realted with feeding response was identified.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.2
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• pp.103-108
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• 2006

Efficacy of aqueous leaf extracts of medicinal plants viz., Eucalyptus globulus, Ocimum sanctum and Piper betle were evaluated against the hatching of eggs, mortality of nymphs and mortality and fecundity of adult mealy bugs (Maconellicoccus hirsutus Green) under in vitro conditions. Totally seven concentrations 1, 5, 10, 20, 50, 70 and 100 percent were tested against mealy bugs. The results revealed that with the increase in the concentration of extracts, there was a corresponding decrease in hatching, nymphal & adult mortality and fecundity in all the extracts tested. The hatching of eggs was minimum at 100 percent concentration in E. globulus (20.00%) followed by O. sanctum (30.42%) and P. betle (36.06%) over control (96.73%). The growth and development of nymphs and adults were adversely affected after the treatment. The nymphs did not attain the adult stage and there was total mortality of nymphs in different treatments. The duration of nymphal stage was reduced by 2-10 days in E. globulus, 1-7 days in O. sanctum and 1-2days P. betle at higher concentrations. However, at lower concentrations it was prolonged by 2-4 days in all the three extracts. At lower concentrations the mortality of adults was on par with the control. Similarly the adult duration was also reduced by 3-4 days at 100 percent concentration and prolonged by 5-6 days at lower concentrations in all the extracts. With the increase in concentrations of the extracts there was decrease in the fecundity of eggs. Thus, the leaf extracts of E. globulus was found to be most effective followed by O. sanctum and P. betle against mealy bugs.

• Journal of Sericultural and Entomological Science
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• v.18 no.2
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• pp.65-78
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• 1976

The mulberry small weevil, Baris deplanata ROELOFS, has highly infested mulberry trees in Korea. As the damage caused by the mulberry small weevil in mulberry fields has been increased over the country since 1969, the authors has carried out a series of biological and controlling studies on the pest from 1971 to 1972. The results obtained are summarized as follows. 1. The adult weevil is elongate oval in shape with black in color and the probocis is long as usual in curculionidae. The size of adult female is 3.30${\pm}$0.04mm in length, 1.47${\pm}$0.04mm in width, and the length of proboscis is 1.25${\pm}$0.014mm, while adult male is 3.28${\pm}$0.06mm in length, 1.40${\pm}$0.04mm in width, and the length of proboscis is 1.30${\pm}$0.02mm. The antenna is geniculate consisting of 12 segments. The terminal sternite of the abdomen has a pointed tip in male but not in female. 2. The egg is long oval in shape, milky white in color, 0.51${\pm}$0.05mm in length and 0.32${\pm}$0.02mm in width. 3. The mature larva is cylindrical and light yellowow in color except the head of dark brown, and legless, 3.88${\pm}$0.06mm in length, 1.40${\pm}$0.02mm width, each segment bearing many wrinkless and short setae. 4. The pupa is long oval, milky white and exarate, 3.53${\pm}$0.09 in length, 1.40${\pm}$0.03mm in width. 5. Majority of the species has one generation through a year and overwinters as adult in xylem of withered branch and come out again from late April to early May in next year. But some of the female oviposit in the same year and the offsprings overwinter as larva (0.4%) or pupa (0.1%) 6. The eggs are mostly laid under the cork layer of withered branch and the number of eggs deposited by an adult female is 73.44${\pm}$8.74, the average egg-laying period is 33.88${\pm}$6.04 days. The incubation period is 11.69${\pm}$0.39 days, the larval period 45.04${\pm}$1.63 and the pupal period 11.05${\pm}$0.49 days. The period of adult's activity is 46.7${\pm}$5.90 days. 7. The larvae feed on the cambium under the bark and adults feed on the winter bud, the latent bud, the leaf stalk and the base of newly shoot. 8. An active period of adults was observed during the period of 4 months from April to July. However, the peak of adult-density occurred in the early May (in the fields of spring-prunning) and early to middle June(in the fields of summer-prunning). 9. There is a positive correlation between the density of larvae and diameter and length of the branches. 10. The pattern of distributions of the adult of mulberry small weevil is negative binomial distribution. 11. The chalcid fly was disclosed to be a natural enemy which was parasite on the larvae of mulberry small weevil and its parasitic ratio was 11.9%. 12. Phosvel D, Malix D, Salithion EC, DDVP EC, and Phosvel EC were effective for the control of adults and Satchukoto-S EC, and Salithio EC were effective for the control of larvae.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.141-151
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• 2002

The success of sericulture industry in India is mainly attributed to the well-planned annual sericultural activity and the systematic implementation of pest preventive and control measures. The insect spectrum of silkworm and its food plants is complex and plays a major role in limiting the production of silk. Insects cause extensive damage to plant whereas predators and parasites either kill the silkworm larvae or force them to spin flimsy cocoons. Unilateral control measure against this pest is mainly based on the use of synthetic organic insecticides. Though these approaches initially paid rich dividends, the undesirable consequences soon surfaced. Insecticide induced resurgence of gall midges, leafhopper, leaf roller, secondary pest out breaks and development of pest biotypes has led to realization of Integrated Pest Management in sericulture. Various components of IPM, viz. Host plant resistance, cultural practices, biological control, chemical control and integrating them at various technological levels have been studied. Sources of host plant resistance have been identified for some of the major insect pests. High yielding mulberry variety has been propagated and their resistances towards major pests have been recorded. Cultural practices like pruning, pollarding, judicious use of nitrogen, optimum spacing and weed management have preyed to be the powerful tools in containing pests. Natural control over the pest population build- up exerted by the wide range of parasitoids, predators and pathogens has been well documented with identification of natural enemies and studies on their potential. Augmentation, through inoculation or inundative releases of parasitic arthropods, is the most direct way of increasing the numbers of these beneficials in sericulture.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.567-575
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• 2012

This study was conducted to investigate the actual conditions of intake of Korean traditional beverages in 273 female university students in Seoul, Korea. The subjects of this study consisted of 128 food and nutrition majors and 145 non-majors. Questionnaires were administered to the subjects who had an average age of 20 years. Two-hundred and nineteen students (80.2%) lived with their parents. Regarding the type of beverages subjects often drink, coffee was the most preferred (51.3%) overall, and non-majors (4.1%) were shown to drink traditional beverages more often. Regarding preference for traditional beverages, most subjects (72.5%) responded that they liked their own traditional beverage. However, for frequency of intake of traditional beverages, 48.7% answered they do not drink any traditional beverages. The reasons why subjects like traditional beverages were taste (71.7%) and health (26.3%), and the type of traditional beverages they often drink were Yulmu tea (35.9%), Sik hae (30.8%), and Yuja tea (10.6%), in order. Regardless of major, ginseng tea, jujube tea, mulberry-leaf tea, Chinese matrimony vine tea, ssanghwa tea, ginger tea, and omija tea were found to be satisfactory traditional beverages. Therefore, due to the low intake frequency, preference, and satisfaction of traditional beverages, new traditional beverages that can meet the standards of female students should be immediately developed.

• Korean journal of applied entomology
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• v.15 no.1 s.26
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• pp.17-21
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• 1976

Four species of the genus Xiphinema have been identified, three of which are new to Korea. X. radicicola which is distributed geographically from the north (Suweon) to the south (Jeiu) of the country is found from soil around roots of apple and elm tree. X. bakeri is a confirmed species to the specimens collected from mulberry grove at Suweon. X. pini was collected from soil around roots of broad leaf lilac and maple trees at Mt. Kyeryongsan. Some notes of Korean populations of X. americanum are given.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.27-32
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• 1995

Studies were carried out to report breeding procedure and characteristics of Fb, a strain of silkworm with abnormal food habit polyphagous. Selection was continued up to the 14th generation toward higher incidence of cabbage leaves feeding variants. In the autumn of 1992(7th generation), selected strain were subjected to severe selection by feeding them on artificial diet that did not contain mulberry leaf powder. The results were clearly positive and reached to higher than 95% of cabbage feeding in the 14th generation. This strain was first discovered by feeding cabbage leaves, but later they were observed to eat some kind of plants like lettuce, Chinese cabbage, radish, beet, apple, persimmon, pear, etc. As described above the procedure, cabbage feeding trait was clearly heritable. The strain responsible for this traits was named Fb.

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.6-8
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• 1991

The study was carried out to investigate the effect of ethrel (2-chloroethylphosophonic acid, 39%) on the graftages quality. Ethrel was sprayed 5 days interval from October 10 to October 30 at 6 places (Suwon (I), (II), Chungju, Kongju, Wanju, Jangsong). Spraying conentration was 1, 000 ppm (400 times dilution). 1. Spray took 3.3 hrs and 500 m of ethrel on 10a eara. 2. The passed rate of graftages decreased 5-8% on the treatments earlier spray than on October 20. 3. New shoot length and number of shoot of the ethrel treatments were the same as the natural leaf falling.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.38-43
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• 1987

The just molted larvae of the fifth instar were fed on with cadmium trated mulberry leaf and on the third day of the fifth instar the daily change of the total protein, activities of GOT and GPT in larvae haemoymph were sexually analyzed. The result obtained are summarized as follows : 1. The total haemolymph was decreased by cadmium treatment. A decreasing ratio of the total haemolymph protein was higher at the later development stage of the male fifth instar than the female fifth instar. 2. There seemed a slight difference in albumin content of the female blood along with the fifth larvae development between control and cadmium treatment where 7% decrease of blood albumin took place with cadmium treatment comparing to that of cotrol. Contrarily a decrease of blood globulin was made on both sexes. 3. The activities of GOT and GPT were inhibited by cadmium treatment.