• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.117-120
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• 2002

Scelionid eggParasitoids Play an important role in biological control of some economically important pentatomids. Stink bug (Canthecona furcellatta Wolff,) is an important predator of Tasar silkworm larvae (Antheraea mylitta D.) and causes 30-40 percent loss in tasar silk industry. Psix striaticeps (Scelionid: Hymenoptera) has been found to be an important egg parasitoid. The parasitization potential of f striaticeps is mere than 60 percent and the sex ratio is female oriented. Studies indicate that the maintenance of existing scelionid population by avoiding harmful practices and the augmentation of scelionids either directly releasing them in the field or by indirectly making the field environment more favorable for them is an important aspect to control the pentatomid population in sericulture. Female bias sex ratio is advantageous to increase the parasitoid population in the field. 24-hour-old egg of stink bug and one-day old parasitoid is suitable for producing maximum progeny. 1 : 30 of parasitoid: host ratio is needed to regulate the estimated population in silkworm rearing field.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.88-95
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• 1997

Olfactometer was used to find the attractiveness of kairomone extracted from gypsy moth (Lymantria dispar) to the egg parasitoid (Ooencyrtus kuvanae). The attractiveness of kairomone extracted from scales and hairs which were attached to the surface of the eggs were higher than that of whole eggs with 79.9% and 67.6% respectively. The probing lantency of the egg parasitoid on the extract of scales and hairs were 115.5 sec. and that of whole eggs were 113.2 sec. Eggs taken from egg mass were shown 91.0% of attractiveness to the egg parasitoid, however only 15% of egg parasitoid were attracted by follicles dissected from the host ovary. The probing latency of egg mass was faster than that of follicles dissected from the host with 84.2 sec. and 114.0 sec. respectively. Egg parasitoid showed the most active attractiveness (88.0%), relatively longer examing period (89.2 sec.) and shorter probing latency (26.8 sec.) to the adhesive materials secreted from reproductive accessory glands of the host. Out of six organic solvents used for the extraction of kairomone from the host egg mass, n-hexane fraction received the most active response from xthe egg parasitoid and the parasitoid reared in vivo showed 3 times higher attractiveness to the n-hexane fraction than that of in vitro.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.281-286
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• 2007

Two hymenopteran egg parasitoid species, Gryon japonicum (Ashmead) (Scelionidae) and Ooencyrtus nezarae Ishii (Encyrtidae), were emerged from eggs of bean bug, Riptortus clavatus Thunberg (Heteroptera: Alydidae). The former parasitoid is first recorded in Korea. Brief morphological and biological characteristics, and parasitism on R. clavatus eggs are described.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.2
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• pp.143-148
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• 2000

The occurrence of Anagyrus kamali, a solitary endoparasite of the mealybug, Maconellicoccus hirsutus has been reported for the first time from India. The parasitoid was fecund to parasitizing the field population of mealybug to the tune of 10.37 to 42.70% in different months. A comprehensive study on the development of the parasitoid on different stages of mealybug indicated that the parasitoid was able to complete its development in all the stages. Higher parasitism (67.48-78.08%) and more female progeny were observed when 3rd instar nymphs and adult female of the mealybug were exposed to the parasitoid. The biology of A. kamali studied at 25${\pm}1^{\circ}C$ temperature and 60${\pm}$$\pm$1.12 days. The duration of egg, larva (3 instars) and pupa were 2.67${\pm}$${\pm}$${\pm}$${\pm}$

• Korean journal of applied entomology
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• v.48 no.1
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• pp.67-72
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• 2009

The kairomonal activity of the aggregation pheromones of Riptortus clavatus for the egg parasitoid, Gryon japonicum, were investigated in soybean field. The parasitism rate of G. japonicum gradually decreased when the distances between pheromone traps and egg sites were increased from 0 to 15 m. The active distance of pheromone source for parasitoid attraction was estimated to be ca. 15 m. Under field conditions, the parasitoid wasp population peaked during the late August and early September, and the parasitism rate increased when the number of pheromone traps was increased from one to three per $165\;m^2$. However, insecticide-treated plots, the level of parasitism recorded is relatively low. Sex ratios in field populations of G. japonicum were female-biased.

• Korean journal of applied entomology
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• v.28 no.4
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• pp.221-228
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• 1989

The oviposition behavior of Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyridae) was examined in a small petri dish containing eggs of gypsy moth, Lymantrt'a dt'spar L. The behavioral sequence from initial searching movement toward the host egg through oviposition, departure, and auxiliary phase activities such as resting, glooming, and host feeding were described. Oviposition experience shortened the approach time to subsequent eggs. The time spent for contacting the host egg also decreased with oviposition experience. Oviposition experience may play an important role in host recognition and increasing oviposition efficiency.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.187-198
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• 2022

In this study, Telenomus remus Nixon (Hymenoptera: Scelionidae) was first reported as a natural enemy of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) egg collected from corn fields in Korea, and its biological characteristics was studied. Based on morphological and molecular analysis, the parasitoid emerged from S. frugiperda eggs was identified as T. remus. We found that T. remus can attack the eggs of S. frugiperda, Spodoptera litra and Spodoptera exigua under a laboratory condition. The longevity of T. remus female adult was longer than that of male adult. The egg-to-adult period of T. remus was not affected by the host age and sex. T. remus female adult laid at least 1-3 eggs a day to a maximum of 37 or more eggs, and the most oviposited on the 3^rd to 4^th day after emergence. The host preference for oviposition of T. remus adult was high in the order of S. litura>S. exigua>S. frugiperda. T. remus preferred to parasitize 1- and 2-day-old host egg rather than 3-day-old host egg. When compared to the sex ratio of T. remus progeny, the rate of female progeny was higher at the initiation time of oviposition, while the proportion of male progeny increased significantly with female adult age, especially after 8-day-old adult. This information may be useful for improving T. remus mass rearing system and developing a biological control program to control S. frugiperda.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.43-50
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• 2005

Parasitism of the egg parasitoid, Trichogramma evanescens, to its main host insect, the Asian corn borer, Ostrinia furnacalis in Korea was compared with that of T. ostriniae that is the dominant species in China on the same host insect. Parasitoid adults of both species emerged more than 50 percent within 4 hours after lights-on in 16L/8D photo period regime and showed a circadian rhythm of emergence. The developmental period from oviposition to emergence in both parasitoids was ca. 11 days and there were no significant differences between the two species and between female and male of each species, either. Both species also showed superparasitism even when the parasitic rates in one egg mass were below 100 percent. Both species oviposited by 5 days after emergence, and maximum longevities of each female adult of both species were 8 day for T. evanescens and 6 day for T. ostriniae. The total number of eggs parasitized by T. evanescens was ca. 38 eggs and ca. 31 eggs by T. ostriniae. Newly emerged female parasitoid laid eggs on about $50\%$ of the host insect egg mass, and the parasitism decreased with the adult age of egg parasitoids in both species. The sex ratio of two species was female-biased about $80\%$.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.435-445
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• 2008

Due to internal feeding behavior, the oriental tobacco budworm, Helicoverpa assulta ($Guen\acute{e}e$), infesting hot pepper has been regarded to be effectively controlled by targeting egg and neonate larval stages just before entering the fruits. This study aimed to develop an efficient biological control method focusing on these susceptible stages of H. assulta. An egg parasitoid wasp, Trichogramma evanescens Westwood, was confirmed to parasitize the eggs of H. assulta. A mixture of Gram-positive soil bacterium, Bacillus thuringiensis subsp. kurstaki, and Gram-negative entomopathogenic bacterium, Xenorhabdus nematophila ANU101, could effectively kill neonate larvae of H. assulta. A sex pheromone trap monitored the occurrence of field H. assulta adults. The microbial insecticide mixture was proved to give no detrimental effects on immature development and adult survival of the wasp by both feeding and contact toxicity tests. A combined treatment of egg parasitoid and microbial pesticide was applied to hot pepper fields infested by H. assulta. The mixture treatment of both biological control agents significantly decreased the fruit damage, which was comparable to the chemical insecticide treatment, though either single biological control agent did not show any significant control efficacy. This study also provides morphological and genetic characters of T. evanescens.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.2
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• pp.180-183
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• 2010

This study was performed to investigate the temperature-dependent development, longevity and oviposition of an indigenous larval parasitoid, Meteorus pulchricornis, on tobacco cutworm, Spodoptera litura. M. pulchricornis were reared at nine constant temperatures between 15 and $35^{\circ}C$. The developmental times of each three developmental stage decreased from 38.7 to 16.3 d between 15 and $30^{\circ}C$. However, M. pulchricornis showed longer developmental time at $32.5^{\circ}C$ (9.5, 7.7 and 17.2 days for each three developmental stage) than at $30^{\circ}C$ (8.9, 7.3 and 16.3 days for each three developmental stage). Immature M. pulchricornis could not develop any more at $35^{\circ}C$. The lower developmental threshold estimated by linear regression equation for the egg to cocoon, cocoon to adult emergence and egg to adult emergence were 5.1, 4.6 and $4.5^{\circ}C$. The thermal constant for each of the three stages were 217.2, 176.2 and 403.8 degree-days, respectively. When no food or 50% honey solution as a food source is provided for M. pulchricornis, the parasitoid survived for 8.3 and 55.9 days at $25^{\circ}C$, respectively. M. pulchricornis females laid 5.2 eggs daily and total of 131.6 eggs at $25^{\circ}C$ until it died. Peak age-specific fecundity was observed on $14^{th}$ day (9.6 cocoons) after parasitoid emergence and gradually decreased thereafter.