• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.237-244
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• 1992

In order to observe the infectivity, growth and development and adult morphology of Metorchis orientalis, a total of 40 chicks were experimentally infected with 100 metacercariae respectively, collected from Pseuderasbora larva. The worms of various developmental stages were recovered from chicks at 1.5, 3, 5, 7, 9, 11, 1:k and 21 days after infection, and they were prepared for morphological observations and measurements. All of the worms were found in the gallbladders of chicks, and their recovery rate was 32% in average. The growth of the body was rapid from 9 to 11 days after infection. The genital primordia appeared in 1.5 and 3-day old worms, and ovary and testes were first observed in 5-day old worms. Thereafter, genital organs gradually matured and completed up to 11 days after infection. The adult worm was leaf-like, and possessed a con- voluted tubular seminal vesicle, an ovoid ovary, a sac-like seminal receptacle, 2 lobed-testes and follicular vitellaria. Eggs were $31.9{\times}15.3{\;}\mu\textrm{m}$ in average size, ellipsoid to elliptical in shape and possessed abopercular thickenings. From the above results, it is concluded that M. orientalis grows in sigmoid pattern in chicks, and their genital organs fully matul.e between days 9 and 11. It is also confirmed that a chick is a new definitive host of M. orientalis.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.327-333
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• 2009

Biological Characteristic of Obolodiplosis robiniae and insecticidal activity of some insecticides against larvae of O. robiniae were investigated. Egg was in oval shape, and its color was light orange and became red when close to hatch. Length of the major axis and the minor axis of egg was 0.4 mm and 0.1 mm, respectively. Larval color was milky and size was 2.6 mm. Pupa was deep brown and its size was about 3.2 mm. Wing and abdomen of adult was black and reddish, respectively. Size of female adult was about 3.3 mm, and larger than male adult. Number of eggs in the ovary was $192.3{\pm}50.7$. First emergence was from late April to late May, and second from late May to late June. Third emergence was from late June to late July. Newly emerged adult escaped from soil, and second and third emerged adult escaped directly from gall of Robinia pseudoacacia leaf. Egg parasitoid was identified as Platygaster robiniae and parasite rate was 51.6%. Among test insecticides, imidacloprid 10% WP and thiacoprid 10% FL showed very strong insecticidal activity against larvae of O. robiniae at 48h later after treatment.

• The Korean Journal of Soil Zoology
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• v.9 no.1_2
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• pp.6-11
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• 2004

Gall development of Nurudea yanoniella on Rhus japonica and emergence of alatae from galls were studied in Jeonju. The galls were formed in late June to late October and slit open in late October 1999. The maximum length and width of galls marked were measured weekly during the period from gall formation to opening. The length and width of galls increased exponentially until mid August. After the 12 September the gall stopped developing Fundatrices (the first generation within the gall) began to larviposit on 24 June and the second generation developed in July to September. The alatiform of the second generation arrived at the final stadium in late September. Consequently, there were at least 4 generations within the galls. Alatae escaped from galls in early October. Correlation between gall and leaf growth indicated that fundatrix might act as a gall forming factor and 2nd-4th generations growing factor. A new species to Korean fauna, Nurudea shirai (Matsumura 1917) was found during this study.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.21-27
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• 2009

Paromius exiguus (Distant) has caused serious damage by pecky grains around Gimpo paddy fields in 2001. We conducted field and laboratory studies to determine the seasonal occurrence and age distribution of P. exiguus on the three major host plants. The overwintering P. exiguus was found mainly on the basal part of gramineae weeds in various localities. After overwintering, in mid-May, the adults aggregated on the grain parts of Imperata cylindrica, laid their eggs and nymphs developed into adults on the same host plants. By the time, the Calamagrostis epigeios colony had newly occupied I. cylindrica areas, the nymphs and adults of first generation had already moved to the second host. The second generation of P. exiguus, after having completed its life cycle on C. epigeios, the newly emerged adults migrated to the rice plants and other gramineae weeds in early August. Afterwards, they complete its third generation cycle where they can move to the overwintering site again. P. exiguus has the five nymphal stages and each nymphal stage could be determined by head or prothoracic width. On the I. cylindrica and O. sativa hosts, the age distribution of P. exiguus showed a simple structure as each stage ratio increased stepwise with time. But in case of C. epigeios, as the newly emerged adults and immature nymphs continuously migrate after a month from the I. cylindrica, the age structure became remarkably complex. The peak nymphal density was observed when the ratio of third and forth instar was the highest in the population. The finding about the specific age structure on each generation of the insect would be very useful in control decision making on the major host plants. It is also important to consider the host's specificity to pesticide sensitivity in relation to various nymphal stages.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.85-89
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• 2004

Numerical measurements were made for fresh weight, body length and width, head width, and color and length of antenna of Japanese pine sawyer, Monochamus alternatus adults, a primary vector of pine wood nematode, Bursaphelenchus xylophilus in Korea. We measured 563 females and 601 males that emerged out of dead pine logs from 2001 to 2002. General linear model analysis showed that measurements of fresh weight, body length, and body width were significantly higher in females than in males. Head width was not significantly different between sexes. Antennal length of males was significantly longer than that of females. For females and males respectively, average fresh weights were 0.305g and 0.277g, body lengths 20.97mm and 19.93mm, body widths 6.52mm and 6.18mm, head widths 3.78mm and 3.70mm, and antennal lengths 31.19mm and 45.49 mm. Antennal length or ratio of antennal length to body length overlapped in some ranges between 2 sexes. Therefore antennal length itself or ratio of antennal length to body length could not be used as a definite criterion to discriminate sexes. However, check on color of the antennae of 4,033 adults revealed without exception that basal part of every segment of flagellum of female antenna was covered with whitish-grey hairs, while whole part of every segment of male flagellum was covered with brownish-black hairs. This characteristics might be a best way to differentiate sex of this species.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.195-200
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• 2006

This study was carried out to clarify the biologies and morphological characteristics of Rhynchaenus sanguinipes. Also some chemicals were tested to screen the effective insecticide for the control of the species. Up to date, Zelkova serrata has been hewn as host plant of Rhynchaenus sanguinipes, which shows serious damage in this country. In the present study, Ulmus pumila was first found as host plant in this study. Body lengths of larvae, pupa and adult were 4.53$\pm$0.30 mm, 3.30$\pm$0.42 mm and 2.96$\pm$0.12 mm, respectively. The overwintered adult of the species emerged on early April to late April, and adult of nekt generation emerged on early May to late May, Pupal periods were 10, 7.2, 5.1 and 4 days on 16, 20, 24 and 28$^{\circ}C$, respectively. The lower developmental threshold temperature was 5.8$^{\circ}C$. Four braconid parasitoids were found as natural enemies, which emerged mainly on late April to early June. Insecticidal activities with treatments of fenitrothion 50% EC, indoxacarb 30% WG, ethofenprox 20% EC and thiacloprid 10% SC was investigated against adult of R. sanguinpes, and they showed >90% mortality.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.479-487
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• 2021

This study investigated the life history of the plum sawfly Monocellicampa pruni Wei, 1998 through field observations and laboratory experiments. M. pruni is a univoltine, complete metamorphosis species with five instars at the larval stage. Adults emerge from the soil around mid-March when Japanese plum trees are in their flowering period. The adults deposit one (rarely two) egg(s) under the epidermis layer of the calyx. After hatching, the larva soon burrows into the fruitlet, consumes the endocarp and remains inside the fruit within its four-time moulting transitions before reaching full growth. At maturity (in May), the larva leaves the infested fruitlet through an exit hole and burrows into the soil at a depth of 2 - 11 cm for spinning its cocoon and hibernates until the next spring as the larval form. Under laboratory conditions (T = 20℃; RH = 40 - 60%), the male lived for a slightly shorter period than the female, 6.03 ± 0.40 and 7.55 ± 0.45 days, respectively. A female could produce 30.29 ± 4.50 eggs in her lifespan. In the field, the duration of the egg was approximately 10 - 11 days and that of the larva was approximately 31 - 34 days.

• Korean journal of applied entomology
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• v.49 no.1
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• pp.11-16
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• 2010

Measurements were made on morphology of each developmental stages of the chestnut weevil, Curculio sikkimensis, reared in the laboratory and field from 2003 to 2006. The size of egg was 0.8${\pm}$0.03 mm. The escaping larvae were measured, in average, as 98 mg in body weight, 10.65 and 3.99 mm in body length and width, and 1.70 mm in head width. Pupal size of female and male was 7.01 and 6.53 mm, respectively. The fresh weight (0.343 g), body length (7.76 mm) and width (3.38 mm), and head width (1.60 mm) of female adults were significantly bigger than those (0.268 g, 7.14 mm, 3.01 mm and 1.37 mm, respectively) of male adults. Proboscis length (6.53 mm) and antennal length (5.47 mm) of female was also significantly longer than those (3.56 and 4.63 mm, respectively) of male. The larvae of C. sikkimensis overwintered for 1~3 years and their body weight, body length, and body width were decreased. The ratio between proboscis length and body length, the basipodite position attached to the proboscis, and shape of the sex organ on the abdominal end could be used to discriminate sexes.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.277-282
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• 2005

This study was conducted to investigate morphological characteristics and effects of temperature on the development of Piezodorus hybneri on soybean. The unibanded stink bug, Piezodorus hybneri, is a serious insect pest in soybean fields giving damage to seeds in pod and leaves of soybean lowering both quality and yield. Eggs were spherical and laid in two raws on the leaves and pods of soybean plants. Body lengths of females and males were 9.8 mm and 8.7 mm, respectively. Egg hatch rates were better in higher temperature within the range of examined temperatures, which ranged in $81.2{sim}93.2%$. The development periods of eggs at the temperatures of 20, 25, 30 and $35^{\circ}C$ were 10.7, 5.0, 4.0, and 3.0 days, respectively. Mean developmental periods of 1st, 2nd, 3rd, 4th and 5th nymphs at $25^{\circ}C$ were 3.2, 3.4, 3.4, 3.3 and 5.9 days, respectively. Development threshold and effective accumulative temperature were $13.3^{\circ}C$ and 65.5 DD (day degree) for egg stage, $9.9^{\circ}C$ and 322.8 DD for nymph stage, $10.7^{\circ}C$ and 386.4 DD from egg to adult, respectively. Oviposition began from 10 days after emergence at $25^{\circ}C$, and the longevity of female and male were 52.5 and 38.2 days, respectively. Total number of eggs and egg masses laid by a female at $25^{\circ}C$ were 496 and 21.3, respectively, The longevity of adult female was shortened with increasing temperature, whereas the total numbers of eggs laid by a female were decreased.

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.92-104
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• 1995

Ten species of Cordyceps species were collected throughout Kangwon province including Chuncheon Dongsanmyun KNU forest experiment from June to September, 1993. Collected Cordyceps species were identified as Cordyceps militaris, C. roseostromata, C. kyushuensis, C. scarabaeicola, Phytocordyceps ninchukiospora, C. nutans, Paecilomyces tenuipes, C. sphecocephala, Hymenostilbe odonatae, Torrubiella sp.. C. militaris, type species of Cordyceps species, was mainly formed on pupae of Lepidoptera and found after the rainy season around July. Fruiting body of C. roseostromata was morphologically similar to those of C. militaris, but relatively small in size and they were also found on lawn or pupa of Lepidoptera. Fruiting body of C. scarabaeicola was found on adult Scarabaeidae specifically and collect fruiting bodies of C. kyushuensis were on larva of moth. C. nutans and C. sphecocephala had host specificity on Hemiptera and Hymenoptera, respectively. Each species formed elliptical fertile part attach to the slim and carneous stalk and they were collected the most in specimen number through whole season of the summer. Ascospore of Phytocordyceps ninchukiospora on seed was characterized by two viable, multiseptate, fusiform units linked end-to-end by a long, filiform connective. Paecilomyces tenuipes, imperfect stage of the genus Cordyceps is multi-infective fungi that attack all stages of all groups of insects. Hymenostilbe odonatae attacks only adult Odonata and Torrubiella sp. formed on spider was difficult to collect because it was found the back side of leaf. As results of cultural test PDA medium showed the best mycelial growth. In the experiment of effect of the acidity inside of the media, C. militaris was good on pH 5, C. nutans and Phytocordyceps ninchukiospora were good on pH 6 and Paecilomyces tenuipes was on pH 7 and C. scarabaeicola was on pH 9. All isolates tested showed the best mycelial growth at $20^{\circ}C$. Morphologically similar isolates were used to analyze protein banding pattern among and within species. As a result, C. militaris, C. roseostromata and C. kyushuensis were clustered into close species and C. scarabaeicola and Phytocordyceps ninchukiospora were relatively distant from those species.