• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.555-561
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• 1999

The development of sycamore lace bug, Corythucha ciliata, had been studied at four constant temperature levels of 15, 20, 25, and $30^{\circ}C$. And characteristics of its oviposition were studied at field. Developmental periods of eggs were 39.1, 17.1, 9.8, and 8.0 days, those of nymphs were 58.5, 23.8, 14.5, and 10.8 days, hatchabilities of eggs were 42.0, 78.5, 83.3, and 78.7%, and survival rates of nymphs were 14.7. 60.5, 75.7, and 48.9% at different temperatures of 15, 20, 25, and $30^{\circ}C$. Lower development threshold temperature and the effective accumulative temperature above the threshold required to complete development from egg to nymph were $11.5^{\circ}C$ and 344.8 degree days, respectively. The optimum temperature was estimated to be $25^{\circ}C$ for developments of egg and nymph. The longevities of adults were 41.0 days and 37.0 days for female and male, respectively.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.5-12
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• 2013

The Hawaiian beet webworm (Spoladea recurvalis) is one of the serious insect pests found on red beet (Beta vulgaris var. conditiva) in Korea. The study was conducted to investigate the development period of S. recurvalis at various constant temperatures, 15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, 32.5 and $35.0^{\circ}C$, with $65{\pm}5%$ RH and a photoperiod of 16L:8D. The developmental period from egg to pre-adult was 51.0 days at $17.5^{\circ}C$ and 14.6 days at $35.0^{\circ}C$. The developmental period of S. recurvalis was decreased with increasing temperature. The relationship between the developmental rate and temperature was fitted well by linear regression analysis ($R^2{\geq}0.87$). The lower developmental threshold and effective accumulative temperature of the total immature stage were $10.4^{\circ}C$ and 384.7 degree days, respectively. The nonlinear relationship between the temperature and developmental rate was well described by the Lactin model. The relationship between the cumulative frequency and normalized distributions of the developmental period for each life stage were fitted to the Weibull function with $R^2=0.63{\sim}0.87$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.1
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• pp.56-62
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• 2020

The meteorological ecology of a soybean variety (Glycine max Merrill) and its characteristics are important factors in selecting soybean variety suitable for the environment. This experiment was conducted to estimate the meteorological- ecological characteristics of soybean for 27 crop cultivation regions in North Korea. The meteorological ecology of each region was determined by the last harvest date and the maximum growth day determined using the daily minimum temperature of the region. The soybean meteorological group for 27 regions in North Korea was classified by eight groups. The last harvest date of group I, the south-west and south-east areas, was from October 21 to 29, which was the latest harvest date among the eight groups. It became shorter toward the central inland and mountainous areas of group IV, and it ranged from September 18 to October 2. The maximum number of growth days was 153~160 days in group I, and 100~111 days in group IV-3, the northernmost area of the east coast. Assuming total growth days as 110 days, the ranges of last flowering dates (and the day length) of group I, II, III, and IV were August 12~19 (day length of 13.5~13.8 h), August 2~6 (14-14.2 h), July 27~August 2 (14.2~14.4 h), and July 10~22 (14.5~14.8 h), respectively. The accumulative temperature of 110 growth days was above 2,400℃ in group II-1, the south to north area of the west inland, and above 2,300℃ in all regions except Cheongjin, Seonbong, and Jung-gang. The accumulative temperature calculated based on the maximum growth day was above 3,000℃ in group I and II-1 and above 2,500℃ in group II-2, the central area of the east coast, III-1, the central inland area, and IV-1, the central inland mountain area.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.387-394
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• 2013

The developmental times of mealworm beetle larvae, Tenebrio molitor were studied at six temperatures ranging from 15 to $30^{\circ}C$ with 60~70% RH, and a photoperiod of 14L:10D. Mortality of larval period was very low at 17 and $20^{\circ}C$ but did not die over $22^{\circ}C$. Developmental time of larva was decreased with increasing temperature. The total developmental time of T. molitor larvae was longest at $17^{\circ}C$ (244.3 days) and shortest at $30^{\circ}C$ (110.8 days). Egg and larvae were not developed at $15^{\circ}C$. The lower developmental threshold and effective accumulative temperatures for the total larval stages were $6.0^{\circ}C$ and 2564.1 degree-days, respectively. The relationship between developmental rate and temperature was fitted by a linear model and nonlinear model of Logan-6($r^2$=0.95). The distribution of completion of each development stage was well described by the 2-parameter Weibull function ($r^2$=0.8502~0.9390).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.3
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• pp.137-152
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• 2004

The climatological characteristics of coastal zone over the southwestern coast of Korea peninsula were investigated using the data observed by AWS (automatic weather system) and 4 buoy points. Coastal zone is climatologically defined as the region bounded by the distinct contrast of temperature gradient and wind speed across coastline. In the southwest of peninsula four cross-lines consisted of AWS aligned with each buoy were selected as Geojedo buoy line, Geomundo buoy line, Chilbaldo buoy line and Dukjukdo buoy line. Analysis on the diurnal cycle and intra-month variation, monthly mean and maximum value, the temperature gradient with distance between buoy and each station and the accumulative frequency of wind speed were applied to find out the characteristics and the range of coast zone. The maximum ranges of coastal zone vary from offshore to Sanglim (about 34 km distance from coastline) for Geojedo buoy line, to Sunchun (about 52 km) for Geo-mundo buoy line, to Jaeundo (about 27 km) for chilbaldo buoy line and to Yongin (about 65 km) for Dukjukdo buoy line. The modification of coastal zone according to synoptic flow was investigated for the onshore, off-shore and calm cases. The ranges of coastal zone are significantly changed with the distance between 65∼90 km for the case of onshore. In addition, we tried to find out the variation of the wind and temperature and the wind ratio of wind speed at ocean to land stations along Geojedo buoy line during 12∼13 Sep. 2003 affected by typhoon (MAEMI).

• Korean journal of applied entomology
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• v.35 no.4
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• pp.302-308
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• 1996

This study was conducted to investigate occurrence and host ranges of Liriomyza trifolii Burgess, American serpentineleafminer, in Chonnam province. Also, temperature effects on the development along with morphologicalcharacteristics in each instar of L. trifolii were studied. L. hifolii was observed from 22 species inthe 7 families. Gerbera, chrysanthemum and tomato were the most damaged host plants. Egg was transparentwhite with lengthlwidth of 0.27 mm10.25 mm while matured larva was yellow with that of 2.03 mm10.80 mmrevealing serpentine gallary under leaf cuticle. Pupa was light brown with that of 1.75 mrn10.74 mm and pupatedon the soil and/or leaf surface. Lengthlwing span of adult was 1.78 mm/3.43 mm. Number of oviposition/sucking punches by L. bifolii adult was 26.1% and 13.3% in tomato and gerbera leaves respectively. Feedingactivity of larval stage was highest at 2OoC. Developmental~threshold (DT) and effective accumulative temperatures(ET) on gerbera leaves were 11.2"C, 33.9DD in egg, 10.3'C, 38.6DD in larva, 10.7"C, 152.3DD inpupa, and 10.8"C, 222.8DD from egg to pupa. On tomato leaves, DT and ET were 13.6"C, 20.2DD in egg, 9.3"C, 43.7DD in larva, ll.O$^{\circ}$C, 114.3DD in pupa, and 11.6"C 178.2DD from egg to pupaDD in pupa, and 11.6"C 178.2DD from egg to pupa pupa.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.461-467
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• 2012

Developmental characteristics of Geocoris pallidipennis were investigated at a constant temperature ($20{\pm}1$, $25{\pm}1$, $30{\pm}1$, $35{\pm}1$, $37.5{\pm}1$ and $40{\pm}1^{\circ}C$), under long day illumination 16:8 (L:D) and constant relative humidity ($80{\pm}10%$). From egg to adulthood, the lower developmental threshold and the effective accumulative temperature were $14.8^{\circ}C$ and 399.1 day-degree, respectively. The experimental results at $35^{\circ}C$ were as follows. The egg period was 5.6 days (hatchability: 81.1%) and the nymphal period was 14.3 days (1st: 3.2, 2nd: 2.2, 3rd: 2.7, 4th: 2.7, 5th: 3.6). Female longevity was 33.8 days and the oviposition period was 29.2 days. Total egg production was 111.2 eggs and the maximum daily egg production was 14.8 eggs (in 7th days). However, although some eggs and nymphs developed at $37.5^{\circ}C$, G. pallidipennis could not develop at $40^{\circ}C$, The total egg production at $40^{\circ}C$ was only 22.1 eggs. When G. pallidipennis was fed on Bemisia tabaci pupae, daily prey consumption by nymphs (1st, 3rd and 5th) and adults was 1.9, 7.3, 18.7 and 29.5, respectively.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.128-135
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• 1998

The experiment was carried out to obtain basic informations on sod culture using water foxtail in apple orchard at Kyeongbuk Provincial RDA in 1996 to 1997. Period of seedling emergence varied with sowing time and accumulative temperature. Sowing at Nov. 25 required longer than 100 days, while it needed only 8 days when water foxtail was sowed at Sep. 20. In a view of accumulative temperature, sowing at March 15 needed $139^{\circ}C$ but it required about $1,000^{\circ}C$ at August 10. This result showed that the seed of water foxtail has strong summer-dormancy in natural condition. Water foxtail had s-shape growth curve during growing season, and growth rate was the highest from March to May in this period. Plant height increased 2 times and 4 times for dry weight from March 20 to April 20. However, growth was decreased by summer depression after May. Major weeds in apple orchard were horseweed, akino-nogeshi and shepherd's-purse. These species were suppressed by the dominance of water foxtail. Water foxtail as a cover plant could be used for a method of weed control instead of herbicide in apple orchard.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.283-289
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• 2013

This study was performed to investigate the biological characteristics of the brown lacewing Micromus angulatus (Stephens) at four different temperatures (15, 20, 25, and $30^{\circ}C$) and $70{\pm}10%$ relative humidity under a photoperiodic regime of 16:8(L:D) h. The developmental threshold and effective accumulative temperature from egg to pupa for M. angulatus were $9.6^{\circ}C$ and 270.3 day-degrees, respectively. The developmental period of egg, larva, and pupa at $25^{\circ}C$ was 4.4, 5.5, and 6.9 days. respectively. The longevity of an adult female M. angulatus was 34.9 days. The oviposition period for M. angulatus was 28.7 days, in which it laid a total number of 515.2 eggs during its life span. The maximum number of eggs laid by a female in a day was 54.8. Daily consumption by M. angulatus at $25^{\circ}C$ was 18.9 $1^{st}$ instars, 47.2 $2^{nd}$ instars, 57.7 $3^{rd}$ instars, and 91.0 adults of the glasshouse potato aphid, Aulacorthum solani. Therefore, M. angulatus could be a promising biological control agent against aphids.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.1-7
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• 2003

Morphological characteristics, developmental period, and seasonal occurrence of Adeia leucomelas (L.) were investigated from 1999 to 2000. In addition, consumption of sweetpotato as food was also examined. Adults of A. leucomelas were dark-brown and body lengths of females and males were 20.2 mm and 18.9 mm, respectively, Wing expanse of female and male was 33.7 mm and 29.4mm, respectively. Egg was flat round-shape. Larva was light yellow-green to dark-brown with 3.3-53.5 mm. Pupa was deep-brown and 15.1 mm in length. Developmental periods of A. leucomelas from egg to adult emergence at different temperatures of 15, 20, 25, and 30$^{\circ}$C were 108.5, 70.7, 40.2, and 29.1 days, respectively, Developmental threshold (DT) and effective accumulative temperatures were estimated as 10.7$^{\circ}$C and 67.5 DD in egg stage, 11.0$^{\circ}$C and 275.1 DD in larval stage and 9.3$^{\circ}$C and 244.6 DD in pupal stage, respectively. The longevity of adult female was shortened with increment of temperature, whereas the total numbers of eggs laid by a female were increased. The larvae of A.leucomelas occurred from mid-June to early October, and population reached its peak during early to mid-September in Jeonbuk province. Food consumption of A. leucomelas was highest at 20-25$^{\circ}$C. Food consumption of 1 st, 2nd, 3rd, 4th, and 5th larvae of A. leucomelas per day at 25$^{\circ}$C was 0.4, 3.6, 19.6, 40.7, and 78.9 $\textrm{cm}^2$, respectively.