• Title/Summary/Keyword: Parasitism rate

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Effect of Cold Storage on Parasitism and Survival of Aphidius colemani and Meteorus pulchricornis (저온저장이 기생성 천적인 콜레마니진디벌과 예쁜가는배고치벌의 기생 및 생존에 미치는 영향)

  • Seo, Meeja;Kim, Jeong Hwan;Seo, Bo Yoon;Park, Hong Hyun;Ji, Chang Woo;Park, Bueyong;Lee, Sang Gu;Cho, Jum Rae
    • Korean journal of applied entomology
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    • v.58 no.4
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    • pp.321-327
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    • 2019
  • When Aphidius colemani mummies were stored at four different temperatures (6, 8, 10 and 12 ± 1℃), they could be stored at 8℃ for 10 days with over 50% adult emergence. A number of mummies of Rhopalosiphum padi parasitized by A. colemani adults emerged from mummies after 8℃ storage clearly reduced with increasing duration of storage and especially declined with storage longer than 13 days showing < 20% parasitism. However, there were no differences in aphid parasitisms by A. colemani on 3 to 10 days after storage. Over 3 day storage at 8℃ was adversely affected on survival of A. colemani adults. Therefore, cold storage of A. colemani adults is considered as an unsuitable method for mass production of biological control agent. When 2-day-old Meteorus pulchricornis cocoons were stored at 6, 8 and 10 ± 1℃, it was possible to be stored up to 63 days at 8℃, showing the highest emergence. With increasing of cold storage duration at 8℃, parasitism on 2nd and 3rd larval instar of Spodoptera litura by stored M. pulchricornis significantly reduced. However, parasitic rate by M. pulchricornis stored for 2 weeks was similar to that by 1 week stored ones. Therefore, M. pulchricornis cocoons could be stored up to 2 weeks at 8℃ for stockpiling before release.

Biological Control of Cotton Aphid by Aphidius colemani(Hymenoptera: Braconidae) in Watermelon Greenhouses (시설 수박에서 콜레마니진디벌을 이용한 목화진딧물 방제)

  • Moon, Hyung-Cheol;Kim, Woong;Choi, Min-Kyung;Kwon, Sung-Hwan;Shin, Young-Kyu;Kim, Dae-Hyang;Hwang, Chang-Yeon
    • Korean journal of applied entomology
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    • v.50 no.1
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    • pp.79-82
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    • 2011
  • Biological control of Aphis gossypii by natural enemies was carried out in watermelon from April to June. Aphidius colemani was released 3 times at rate of $2/m^2$ to control A. gossypii(April 24, May 8, and May 22 in 2007). In A. colemani-released plots, A. gossypii showed low population density of < 0.6 per leaf with the highest parasitism of 57.2%, and 2.0~10.6% in the percentage of leaves with aphids. In control, the population of A. gossypii kept on increasing from early May and reached 653.2/leaf on may 29.

Nutritional Situation in Korea (한국인영양(韓國人營養)의 현황(現況))

  • Ju, Jin-Soon
    • Journal of Nutrition and Health
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    • v.1 no.1
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    • pp.37-42
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    • 1968
  • According to the dietary surveys and national food balance sheets, the dietary state of person living in Korea is ingesting a high level of grain and vegetable diet and very low animal sources. The daily calory intake is about 2,300-2,600 Cal. per head in which a total protein intake is 69-86 gm respectively. These data indicate no shortage of calory and total protein intake. However, the intake of animal protein is only 4-11 gm and the fat is 8-18 gm, both of which are far below the requirment. The low fat intake brings about a low level of fat soluble vitamins, and that V-A intake is as short as the half amount of the allowance. Riboflavine is also about a half of dietary requirment. Both thiamin and ascorbic acid intake are sufficient. The calcium intake is 0.26-0.5 gm per day which is inadequate. In fact, biochemical findings through field survey show; serum protein 6.7 gm, hemoglobin 13.1 gm and hematocrite 41.5% all of which are lower than the Kwon's report. The serum V-A and uunrinary riboflavin value are also lower than the Williams'es report. Clinically, inflamation of the eyes, cheilosis, pathological signs of tangue, xerosis of the hand and arm, or the like are frequently seen. On the other hand, there is no suitable diet available for the weaning infant and delayed weaning is a common practice. A school lunch program is still in an early stage of development. Another example can be cited that the Korean infant grows faster than the Japanese until one year of age, and no difference is noted between the Korean and the American infants up to six monthes of age, thereafter the former lags in the growth rate. This might be mainly due to the nutritional reasons as mentioned above, and in part due to the high inidence of intestinal parasitism and others.

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Epidemiological study on prevalence of fascioliasis in slaughtered cattle (도축 소의 간질 감염실태에 관한 역학적 고찰)

  • Kim, Yong-Hwan;Park, Jong-Tae;Kim, Jae-Ik;Kim, Hyun-Joong;Kim, Tae-Soon;Jang, Mi-Sun;Kim, Jeong-Nam;Park, Duk-Woong;Bae, Seong-Yeol;Park, Ja-Yoon;Seo, Eun-Ju
    • Korean Journal of Veterinary Service
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    • v.31 no.2
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    • pp.207-217
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    • 2008
  • This study was carried out to investigate the prevalence of fascioliasis of slaughtered and farmed cattle in Gwangju area from February to November in 2007. A total of 1,000 cattle fecal samples were collected from slaughter houses (n=805) and farms (n=185). Twelve (1.2%) were found as positive cases with excretion of the egg of Fasciola spp in the fecal specimens, and 128 (12.8%) were positive in intestinal parasitism using the flotation and sedimentation procedures. The infection rate of fluke larvae from the slaughtered cattle at abattoirs in Gwangju was 0.75% (6 out of 805 heads). In histopathology, there were several liver lesions such as inflammation with infiltration of eosinophil, polymorphonuclear cells, mononuclear cells and multinucleated giant cells, proliferation of connective tissue, calcification and abscess formation.

Studios on the Parasites of the Rice Planthoppers I. Egg Parasitism Anagrus nr. flaveolus WATERHOUSB (Hymenoptera : Mymmaridae) on the Rice Planthoppers (멸구 매미충의 기생성 천적에 관한 연구 I. Anagrus nr. flaveolus의 멸구류 난기생에 관하여)

  • Kim J.P.;Yoo C.Y.;Kim C.H.
    • Korean journal of applied entomology
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    • v.21 no.2 s.51
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    • pp.87-94
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    • 1982
  • The mymarids egg parasite of rice planthopper, Anagrus nr. flaveolus, were investigated to know their parasitic activities after overwitering in the paddy banks and barley fields, their host preferences and seasonal variations in the pesticide sprayed and unsprayed paddy fields of Gyeongnam province O.R.D. at Jinju from 1977 to 1979. The parasitic activities of Anagrus nr. flaveolus after overwintering in the paddy banks were high early in April and tended to decrease remarkably since mid-April by moving to the barley fields. The parasitic rate of Anagrus nr. flavelous was $47.2\~88\%$ between middle and late in April, the peak of egg deposition period. Anagrus nr. flaveolus parasitized Laodelphax striatellus, Nilaparvata lugens, and Sogatella furcifera, but didn't attack the eggs of Nephotettix cincticeps in the paddy fields. High preference was observed with Laodelphax steriatellus. The parasitic activities of Anagrus nr. flaveolus in the pesticide sprayed paddy fields were high in early July and from late August to early September. The parasitic rate in the pesticide unsprayed fields were higher than those of sprayed fields during the pesticide spraying period, from July to August and parasitic activities were active from October to before coming winter.

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Mass rearing system for Neodryinus typhlocybae(Hymenoptera: Dryinidae) as a biological control agent of Metcalfa pruinosa (미국선녀벌레 천적인 선녀벌레집게벌 대량사육 체계)

  • Meeja Seo;Jeong Hwan Kim;Hyeon Jung Noh;Bo Yoon Seo;Jum Rae Cho;Hong Hyun Park
    • Korean Journal of Environmental Biology
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    • v.40 no.4
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    • pp.423-432
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    • 2022
  • The mass-rearing system for Neodryinus typhlocybae as a biological control agent of Metcalfa pruinosa was established. Depending on the density of host nymphs and plants, the average number of cocoons produced by the parasitoids was 5-8 and 70-150 cocoons per leaf and sapling of mulberry, respectively. There is a significant difference in cocoon length between females (6.10-6.46mm) and males (4.20-4.62mm). Sex determination of cocoons before emergence will be helpful for efficiently releasing this parasitoid in fields. The parasitic rate of N. typhlocybae at the semi-field condition was on average 13-17%. The release number of this parasitoid did not affect parasitism. Nevertheless, the population growth rate of M. pruinosa was reduced by increasing the release number of N. typhlocybae. The parasitoid offspring's sex and bivoltine were influenced by the host age. On young host nymphs, the bivoltine portion of parasitoid increased. When parasitized on 4th or 5th nymphs, the offspring's female ratio of N. typhlocybae increased. This result may be useful for potentially controlling mass rearing production of parasitoid.

Effect of Forage Feeding on Goat Meat Production: Carcass Characteristics and Composition of Creole Kids Reared Either at Pasture or Indoors in the Humid Tropics

  • Alexandre, G.;Limea, L.;Fanchonne, A.;Coppry, O.;Mandonnet, N.;Boval, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.8
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    • pp.1140-1150
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    • 2009
  • Forage diets provide good quality carcasses in sheep but very little is known in tropical goats. An experiment was designed with Creole male goats using grass-based systems to assess carcass yield, scores, cuts and composition. After weaning (84 d, 9.2 kg LW) two modes of forage feeding were compared with two replicates of each. Feeding groups were: PF for animals reared at pasture (n = 62) and IF when reared indoors (n = 60). Given that forage finishing will result in low ADG it appeared necessary to study different fattening lengths. The kids were equally divided into 4 groups: group A (n = 32), 4mo after weaning; group B (n = 32), 4mo after A; group C (n = 30), 3mo after B and group D (n = 28), 2mo after C. The animals grazed (in two sub-flocks) on irrigated tropical pastures managed in a rotational system (28 d of re-growth) at a mean stocking rate of 1,200 kg/ha/yr LW. The IF groups were reared in collective pens on a slatted floor (2 replicates of 7 or 8 kids each). They were fed the same stand of tropical grass (25% DM, 12% CP) as that of pasture that was cut daily and provided ad libitum. The ADG (-10%), the weights of omental fat (-60%) and fat in shoulder (-18%), the ultimate pH of carcass (-12%), the meat colour score (-24%), the ""parameter accounting for redness (12%) and the DM and lipid contents (-4%) were significantly lower (p<0.05) in PF than in IF, while the liver was heavier (+23%, p<0.05). Feeding conditions seemed to be similar, thus, differences could be related to gastrointestinal parasitism in the PF system and hypotheses are discussed. Increasing the fattening duration, resulted in significant difference (p<0.01) in many traits: the weights at slaughter and of carcass increased by 40% and 60% from groups A to D and consequently the weights of body compartments and carcass cuts (1.5 to 2.0 fold more). When the results were presented as percentage of empty body weight and carcass weight, these preliminary results (carcass weight 9kg and yield 53%, muscle proportion 70%) and qualitative parameters (low fat score 2/5, fat proportion 5%), seem to be a good incentive for the sector to develop a niche market to meet consumer lean meat expectations. The indoors system could be implemented where there was low availability of grazing areas or problems of dog attacks.

Seasonal Occurrence of Campoletis chlorideae Uchida and Its Control Efficacy on the Oriental Tobacco Budworm, Helicoverpa assulta (Guenee), in Tobacco Fields in Suwon (수원지방 담배포장에서의 Campoleits chlorideae의 발생소장과 담배나방 방제효율)

  • B.S. Nandihalli;Joon-Ho Lee
    • Korean journal of applied entomology
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    • v.34 no.2
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    • pp.147-153
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    • 1995
  • The occurrence of Oriental Tobacco Budworm (OTB), Helicoverpa assulta (Guenee), larvae in early and late planted tobacco fields showed tow or three distinct peaks. The parasitoid, Campoletis chlorideae Uchida, occurred for a short period with one peak following th second peak of OTB in early planted fields. However, in late planted fields, the parasitoid occurred as long as the OTB larvae were abundant. The OTB larval density was higher in late planted fields than in early planted fields. Among four varieties of tobacco, the OBT larval occurrence was relatively high on NC-744 throughout the season. However, more parasitoid cocoons were found in Burleyf-21 and NC-82. The seasonal occurrence of the larval parasitoid, C. chlorideae, assessed by an OTB larval release and recovery method, continued from late June to early September and relatively higher abundance was noticed from early July to late August. In a field cage evaluation of C. chlorideae as a biological control agent of OTB larvae, higher rate of C. chlorideae release (4 females/2$\m^2$) resulted in higher larval parasitism (86.1%) and less leaf damage (8.7%) in tobacco. The leaf damage by OTB larvae was significantly high in the untreatment plot (23.2%) and the lowest damage (1.6%) was recorded in the chemical treatment plot.

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A Study on the Current Situation of Adult Children Cohabiting with Their Parents and an Exploration of the Frame of Analysis (성인자녀의 부모 동거 현황 및 분석틀의 탐색)

  • Choi, Youn Shil
    • Journal of Families and Better Life
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    • v.32 no.4
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    • pp.75-89
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    • 2014
  • The purpose of this study is to explore whether the phenomenon of both married and unmarried adults' cohabiting with their parents in Korean society is "unilaterally parasitic" on the child's side, or is "interdependent", characterized by expectation and dependence from the parent's side. As a result of this study possessing the characteristics of theoretic research, the following propensities of parent-dependent adults have been discussed. First of all, it was discovered that the ratio of adult children dependent on and cohabiting with their parents is considerable. Second, parents cohabiting with their adult children have unfavorable sociological features, such as high age, low level of education and income, and lower standards of education and income, compared to parents in normal households. Third, it was found that parent-dependent adults in Korean society maintain a relatively high rate of financial activity and stable employment-based occupation status. Fourth, it was shown that the level of satisfaction on the relationship between parent-dependent adults and their parents was discovered to be high, which is contrastive to the prediction of negative results based on some previous researches. Single adult children's age, their level of education and financial activity status, and their parents' age and level of education were deducted as variables related to the level of satisfaction of the relationship between parents and their children. It seems that the issue of married and unmarried adults' cohabiting with their parents in Korean society should be approached from various perspectives such as political, economic, socio-cultural and developmental aspects. On the basis of this fundamental awareness and several of the materials, it is pertinent that approaches to both married and unmarried adults' cohabiting with parents in Korean society should be distinguished from approaches to those in Japanese or Western society because it reflects the uniqueness of Korean society. In the phenomenon of married and unmarried adults' cohabiting with their parents in Korean society, there are several factors besides the economic factor, especially the socio-cultural factor that have the characteristics of mutual dependence between parents and their children rather than those of unilateral parasitism, in contrast with the phenomenon in Japanese or Western society. This research was aimed to contribute by establishing basic data for policy making by providing necessary information to treat the issues of instability and anxiety related to families and reflection on the matters of generations and parent-child relationships in current Korean society.

Plant Parasitic Nematodes in Soybean in Korea and Their Importance Rating (국내 콩 기생성선충의 중요도 등급)

  • Kim, Donggeun;Choi, Insoo;Ryu, Younghyun;Huh, Changseok;Lee, Younsu
    • Korean journal of applied entomology
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    • v.52 no.4
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    • pp.327-333
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    • 2013
  • Plant parasitic nematodes were isolated from 274 soil samples collected from soybean fields in Korea. Nematode importance rating in soybean is proposed based on this study and by reviewing other reports. Soybean cyst nematode, Heterodera glycines is the most important nematode species and rated as $1^{st}$ because it detected from 38%(range 25-51%) of soil samples with high density except Jeju province. Root-knot nematode, Meloidogyne spp. is rated $2^{nd}$ and is more widely distributed in southern provinces, Gyeongnam, Jeonnam, and Jeju province (detection rate ranged 16-44%). Pratylenchus is rated $3^{rd}$ and is more frequently detected from northern provinces such as Gyeonggi and Gangwon (detection rate ranged 10-13%). Helicotylenchus is rated $4^{th}$ and is particularly important in Jeju province (detection rate is 62% and numbers averaged 571 nematodes/$300cm^3$ soil), which is the main production area for sprouting soybean in Korea. Tylenchorhynchus, Paratylenchus, Criconema, Criconemoide, Mesocriconema, Ogma, Xiphinema, Paratrichodorus, and Trichodorus occur in low frequency and density, thus they are rated to $5^{th}$. We propose to delete following nematode genus from the list of soybean parasitic nematode in Korea because their parasitism on soybean is unconfirmed or negligible; Tylenchus, Aphelenchus, Aphelenchoides, Ditylenchus, Hirschmanniella immamuri, Basiria graminophila, Psilenchus, and Pseudhalenchus. Therefore, we revised 30 species in 16 genera as soybean parasitic nematodes in Korea. Importance rating is $1^{st}$ Heterodera glycines, $2^{nd}$ Meloidogyne spp., $3^{rd}$ Pratylenchus spp. and $4^{th}$ Helicotylenchus spp. especially in Jeju province.