• Asian Journal of Turfgrass Science
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• v.12 no.3
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• pp.225-236
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• 1998

The white grubs in turfgrass were investigated from 15 golf clubs in 7 provinces and 2 metropolitan cities. 12 white grub species were collected and 11 species in 8 genera including oriental beetle, Anomala orientalis were identified but 1 species was not identified. The oriental beetle grub was the most serious pest in turfgrass out of them. The brown chafer, Adoretus tenuimaculatus was widely distributed species collected from 6 golf clubs, Maladera castanea was collected from 5 golf clubs and A. orientalis, Holotrichia kiotoensis, and M. orientalis were collected from 4 golf clubs. The white grubs, their density, and distribution depth were also observed at tee, fairway, and green from Yongweon, Daegu, and Dongrae golf clubs. A. orientalis was dominant species in overwintering season but A. tenuimaculatus was dominant one in unoverwintering season. The density of white grubs was low in the green compared with tee or fairway. Distribution depth was different depending on season in Daegu and Dongrae golf clubs but not different in Yongweon golf club. Although there showed no differences in white grub species depending on turfgrass but density was different, that is, A. tenuimaculatus was abundant in Zoysia matrella while A. orientalis abundant in Poa pratensis. The density of A. orientalis grubs was higher in older golf courses but there showed no differences in white grub species depending on the age of golf club.

• Korean journal of applied entomology
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• v.55 no.3
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• pp.235-243
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• 2016

The winter cherry bug, Acanthocoris sordidus (Thunberg), is an insect pest hat damages plants from Solanaceae and Convolvulaceae. The developmental period from egg to adult averages 76 days at $25^{\circ}C$. Adult egg-laying occurred irregularly via spawning, averaging 195 (up to 468) eggs per individual on the abaxial leaf surface of the host plant. Results of linear regression indicated that the lower developmental threshold temperature was $13.9^{\circ}C$ and the effective accumulated temperature was 526.3 DD. Data from a pepper field in 2015 indicated that overwintering adults first appeared during late June (daily average temperature = $25.7^{\circ}C$), reaching maximum density by early September. A choice test examining colonization preferences using a net cage and a Y-tube olfactometer revealed that females gravitated toward conspecifics (other females, males, or both), whereas males moved toward empty areas. Finally, we found that communal breeding results in a longer developmental period and higher eclosion rates than solitary breeding. Developmental periods and eclosion rates were also for colonies in a large space than for those in a small space. This outcome suggests that colonization effects on insect development are stronger in a smaller area.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.335-339
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• 2019

The white peach scale (Pseudaulacaspis pentagona) is a significant pest of trees belonging to the Rosaceae family. We investigated the effect of ten insecticides on hatching rate of first instar white peach scale larvae (crawlers). The insecticides are Dinotefuran WG, Benfuracarb WG, Pyrifluquinazon WG, Clothianidin SG, Buprofezin WP, Buprofezin+Imidacloprid SC, Buprofezin+Etofenprox WG, Buprofezin+Thiacloprid SC, Benfuracarb+Buprofezin WG, Acetamiprid+Buprofezin EC. We observed that several crawlers emerged in early May, with the average number being 45.7. Hatching period was approximately 14 days, and the hatching success rate was approximately 77.7%. Overwintering females produced an average of 58.7 eggs. All insecticides achieved 100% mortality in crawlers. Our results suggest that these insecticides can effectively control white peach scale when used at the crawler stage.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.129-136
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• 2002

Agamermis unka, a mermithid parasite of brown planthopper (BPH), Nilaparvata lugens, is the most important natural enemy of BPH and white-backed planthopper (WBPH), Sogatella furcifera in Korea. Distribution of A. unka was investigated in Korean rice fields from 1992 to 1998 and in 2001. Overwintering population of A. unka in Gosung, Namhae, and Tongyoung from 1992 to 1998 was different depending on locality and year. In the survey of A. tanka distribution in the spring of 2001, A. unka was found only at Jangheung and Haenam in Jeonnam province and Namhae, Jinju, Sancheong, Sacheon, Gosung, Tongyoung, Uiryeong, Changwon, Gimhae, and the experimental field of Gyeongsangnamdo Agricultural Research and Extension Services at Jinju in Gyeongnam province out of 30 observed regions in 5 provinces. The number of A. unka was 1,045/㎥ at Namhae, 947/㎥ at the experimental field of Gyeongsangnamdo Agricultural Research and Extension Services, and 395/㎥ at Gosung. Density of A. unka at the rice paddies of Gyeongnam province after harvest in 2001 was higher at the rice fields of Namhae, Gosung, and the experimental field of Gyeongsangnamdo Agricultural Research and Extension Services. Although density of A. unka was higher in the pesticide-untreated plots than fungicide-treated or insecticide-treated plots of forecasting paddies, there were no significant differences. After rice harvest A. unka was found from the forecasting paddies of Gosung, Jinju, Namhae and Sacheon out of 19 observed localities in Gyeongnam province.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.123-128
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• 2002

This study was carried out to test the effects of temperatures between 2$0^{\circ}C$ and 3$0^{\circ}C$ on the reproduction and development of the rice water weevil, Lissorhoptrus oryzophilus. Preoviposition periods were much longer (17.2 to 51.0 days) in the overwintering adult females collected in March than those collected in May, regardless of temperature. Oviposition periods, however, were longer (16.9 to 22.0 days) in the adult females collected in May than those collected in March at the same temperatures. The longer oviposition period observed in the females collected in May were directly associated with higher fecundity. Egg periods were shortened from as temperature increased, but the hatching rate was highest (100%) at 27$^{\circ}C$. The developmental periods from egg to adult were shortened as temperature increased : from 77.9 days at 2$0^{\circ}C$ to 38.3 days at 3$0^{\circ}C$. The developmental zero point temperature (T) and the total effect temperature (K) for egg were 16.3$^{\circ}C$ and 62.1 dgree days, respectively. The T and K from egg to adult emergence were 13.9$^{\circ}C$ and 577.6 dgree days, respectively. The adult females of the first generation did not oviposit at 2$0^{\circ}C$, but did at $25^{\circ}C$ and 3$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) increased as temperature augmented. Net reproductive rate (Ro) per generation was highest (75.3) at $25^{\circ}C$.>.

• Research in Plant Disease
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• v.13 no.3
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• pp.131-136
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• 2007

Occurrence of popcorn disease on mulberry fruits was surveyed in several locations in Korea from 2005 to 2007. The diseased fruits turned grayish white and changed to hard and black sclerotia during overwintering after falling onto the ground. Apothecia produced from overwintered sclerotia in the fields of mulberry trees were observed in early May. Two types of apothecia were produced from the sclerotia, which were cup-shaped or club-shaped. The fungus with cup-shaped apothecia was identified as Ciboria shiraiana, and that with club-shaped apothecia as Scleromitrula shiraiana. C. shiraiana occurred at the ratio of about 6 vs. 4 in the fields. Occurrence of the disease differed remarkably depending on years, locations, and varieties of mulberry trees investigated. Field survey of the disease incidence showed that Baekhahyeongsang, Dahojosaeng, Hasusang, a native variety and Sawonppong 22 were resistant to the disease, Cheongilppong, Daeseongppong, Guksang 20 and Turkey-D were moderately susceptible, and Cateneo, Moreji and Sanggwa were highly susceptible. Disease incidence in the fields mulched with nonwoven fabrics or plastic films was much lower than that in the non-mulched fields. Disease incidence in the fields mulched with rice straws was similar to that in the non-mulched fields.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.38-44
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• 1996

These experiments were conducted to investigate the ecological characteristics of Amblyseius womersleyi Schica,which was biological agent in the integrated management of tea red spider mite, Tetranychus kanzawai Kishida.At four constant temperatures of 15, 20, 25, and 30$^{\circ}$C, the periods of A. womersleyi from egg to adult emergencewere 22.8, 9.6, 4.8, and 3.6 days, respectively. Developmental threshold and effectively cumulative degree-day from egg to adult emergence were 12.7"C and 61.4DD, respectively. Preoviposition periods of A.womersleyi were shorter than oviposition and postoviposition periods. The number of eggs laid per female was21.7, 28.1, 34.2, and 48.0 at the respective temperatures. The intrinsic rates of increase were estimated to be 0.064, 0.139, 0.349, and 0.402; the mean generation times were 36.0, 19.3, 8.6, and 7.7 days; the populationdoubling times were 10.8, 5.0, 2.0, and 1.7 days, respectively. A. womersleyi overwintered on green weeds, fallenleaves and in the soil surface as adult females. A. womersleyi gravid female consumed 3.0, 4.9, 15.7, and19.4 eggs of T. kanzawai per day at 15, 20, 25, and 30$^{\circ}$C, respectively. A. womersleyi protonymph consumed4.6 eggs, deutonymph 6.3 eggs, and female during oviposition consumed 19.4 eggs, and 6.8 eggs of T. kanzawaiduring postoviposition per day at 30$^{\circ}$C. at 30$^{\circ}$C.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.73-82
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• 2000

Two Psyllidae species of Cacopsylla pyricola (Foerster) and C. pyrisuga (Foerster)damaging pear trees have been reported in Korea. However, their ecological characteristics and damagepatterns have not been evaluated yet. To establish basic control measures of C. pyricola, field phenology,overwintering ecology, seasonal fluctuation and temperature-dependent development of C. pyricola wereexamined. C. pyricola overwintered under the bark scale of pear trees as winter form adults and theymoved to fruiting twigs from mid-February. Honeydew produced by C. pyricola nymphs and adults asthey feed caused serious black sooty mold on leaves and fruits. The seasonal occurrence of C. pyricolawas different every year. In 1993, characterized by cold temperature and heavy precipitation, C. pyricolapopulation was maintained highly during growing season. However, the population was decreased rapidlyfrom early July in 1994, year of hot and dry weather condition. In 1995, year of average temperature, thedensity of C. pyricola population was decreased during hot months of July and August, and rebuilt up inSeptember and October. The development periods of C. pyricola eggs were 13.33 days at 15"C, 9.32 daysat 20$^{\circ}$C, 7.82 days at 25"C, 6.60 days at 30$^{\circ}$C, and 7.75 days at 35$^{\circ}$C. The development periods ofnymphs were 33.75 days at 15OC, 23.77 days at 20$^{\circ}$C, 15.21 days at 25"C, and 17.40 days at 30$^{\circ}$C. Theirdevelopment periods and mortalities were increased in higher temperatures. The parameters of nonlineardevelopment model, Weibull and linear development models of Cacopsylla pyricola were estimated.models of Cacopsylla pyricola were estimated.

• Korean journal of applied entomology
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• v.14 no.2 s.23
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• pp.65-70
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• 1975

The study was planned to detect resistance levels of striped rice borers (Chilo suppressalis Walker) and green rice leafhoppers(Nephotettix cincticeps Uhler) from different localities to organophosphate and carbamate insecticides using topical application. Strains of overwintering striped rice borers were collected from 7 different areas in Gyeonggi Province and they were kept under conditions of about $25^{\circ}C$ for 10 days. Overwintered and reared larvae of striped rice borers were compared for response to insecticides. The strains of green rice leafhopper were collected from Iri, Milyang, Pyongtaek, Echeon and Suweon. Insects were multiplied in the lab. All insecticides tested were organphosphates(MPP, MEP and Diazinon) and carbamate (NAC), which have been used in control of rice insect pests for over past 10 years. The results obtained were as follows; a. With MPP compound, resistant levels of the Joam, Suweon, and Echeon strains of C. suppressalis were from 2 to 4 times as compared with the Yangpyong strain. b. With MEP insecticide, resistant levels of the Kimpo, Pyongtaek, Yongin, Echeon, Suweon, and Joam strains of C. suppressalis were from 2 to 6 times as compared with the Yangpyong strain. c. With Diazinon, resistant levels of the Suweon strain of C. suppressalis were 3 times greater than the Yangpyong strain; but the resistant levels of Kimpo, Pyongtaek, Yongin, and Echeon strains approximated the later. 4. The overwintered larvae of C. suppressalis were more tolerant to the insecticides than the larvae reared in the lab. e. With MEP, resistant levels of the Iri, Milyang, and Pyongtaek strains of N. cincticeps to the Suweon strain showed 13, 8, 7 and4 times, respectively. f. With MPP, resistant levels of the Iri and Pyongtaek strains of N. cincticeps were 7 and 4 times as compared with the Suweon strain, respectively. g. With NAC, resistant levels of the several strains of if. cincticeps showed no difference, and seemed not to have developed resistance yet.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.459-466
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• 2009

There was different between two differential geographical and environmental condition areas on elytra color expression patterns of the multicolored Asian lady beetles (Harmonia axyridis). Especially, it was investigated that expression rates of melanic patterns (conspicua, spectabilis and axyridis) relatively increased in overwintering populations collected in highly mean temperature and longer cumulative daylength area. In addition, in the same collection site, the seasonal difference had influenced on color patterns of H. axyridis. Although these effects didn't were not observed in the laboratory, environmental conditions such as temperature or cumulative daylength might be factors that gave an effect on color pattern formation.