• Korean journal of applied entomology
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• v.51 no.3
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• pp.235-243
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• 2012

Population dynamics of the American serpentine leafminer, Liriomyza trifolii (Burgess), were observed and modeled in order to compare the effects of air and tomato leaf temperatures inside a greenhouse using DYMEX model builder and simulator (pre-programed module based simulation programs developed by CSIRO, Australia). The DYMEX model simulator consisted of a series of modules with the parameters of temperature dependent development and oviposition models of L. trifolii were incorporated from pre-published data. Leaf surface temperatures of cherry tomato leaves (cv. 'Koko') were monitored according to three tomato plant positions (top, > 1.8 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at the same three positions using a self-contained temperature logger. Data sets for the observed air temperature and average leaf surface temperatures were collected (top and bottom surfaces), and incorporated into the DYMEX simulator in order to compare the effects of air and leaf surface temperature on the population dynamics of L. trifolii. The initial population consisted of 50 eggs, which were laid by five female L. trifolii in early June. The number of L. trifolii larvae was counted by visual inspection of the tomato plants in order to verify the performance of DYMEX simulation. The egg, pupa, and adult stage of L. trifolii could not be counted due to its infeasible of visual inspection. A significant positive correlation between the observed and the predicted numbers of larvae was found when the leaf surface temperatures were incorporated into the DYMEX simulation (r = 0.97, p < 0.01), but no significant positive correlation was observed with air temperatures(r = 0.40, p = 0.18). This study demonstrated that the population dynamics of L. trifolii was affected greatly by the leaf temperatures, though to little discernible degree by the air temperatures, and thus the leaf surface temperature should be for a consideration in the management of L. trifolii within cherry tomato greenhouses.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.353-358
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• 2008

The bean pyralid, Omiodes indicatus (Fabricius), moulted 4 times during larval period. When temperature increased from 15 to 20, 25, and $30^{\circ}C$, the developmental period of immature stages was shortened; 18.2, 7.5, 5.0, and 4.1 days of egg period; 51.8, 20.0, 12.7, and 9.9 days of larval period; 29.5, 12.0, 8.0, and 5.9 days of pupal period, respectively. Adult longevity was 16.0, 14.7, 11.2, and 7.5 days at respective temperatures. A female adult layed 57.0, 63.3, 82.2, and 31.7 eggs in 3.7, 6.0, 5.8, and 3.0 days of oviposition period at the same temperature regimes, respectively. Field survey in 2006 and 2007 showed that leaf damage on paddy field and upland soybeans began to appear in mid July, reaching its peaks in mid August and late September. Adults of the bean pyralid appeared in mid July and peaked in late August and early October.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.181-186
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• 2011

To predict the bud bursting date of 'Campbell Early' grapevines, the bud developmental rate (DVR) models were constructed. The DVRs for bud bursting were calculated from the demanded times at controlled air temperatures. The DVRs were examined on the 'Campbell Early' grapevines incubated in three different temperatures at 4.6, 11.8, and $16.6^{\circ}C$. The DVR increased exponentially or linearly on the air temperature with a slope of about 0.0019. The DVR equations were computed as $DVR=0.0249+0.0020e^{0.1654x}$ or DVR = 0.0019x + 0.0187. These DVR equations offered developmental indices and predicted dates for bud bursting with air temperature data. The DVR equations were validated to the bud bursting data observed in the field. When bud bursting dates were calculated with daily temperature data, the root mean squared error (RMSE) between the observed and the predicted dates was less than 4 days. When those were calculated with hourly temperature data, on the other hand, the RMSE was less than 3 days. These results suggest that the DVR models are useful to predict bud bursting date of 'Campbell Early' grapevines.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.189-195
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• 2012

To predict the blooming date of 'Yumyeong' peach trees, the models for flower bud developmental rate (DVR) were constructed. The DVRs were calculated from the demanded times at controlled air temperatures. The branches of 'Yumyeong' peach trees were incubated at three different temperatures of 9.7, 15.2, and $18.9^{\circ}C$. The DVRs were also constructed with blooming dates and air temperatures in the field, collected from 1979 to 2008 at the experimental orchard of National Institute of Horticultural and Herbal Science, Suwon, Korea. All the DVRs increased linearly or exponentially with air temperature. The DVR equations evaluated under controlled air temperatures were y=0.0018x+0.0051 and y=$0.0125e^{0.0603x}$. The DVR equations under field conditions were calculated as y=0.0039x-0.0112 and y=$0.0062e^{0.1512x}$. These DVR equations offer developmental indices and predict the date for blooming with air temperature data. These DVR equations were validated against the blooming data observed in the field. When the blooming dates were calculated with exponential DVR equations and daily air temperature data, the root mean squared errors between the observed and predicted dates were around 2 days. These results suggest that the DVR models are useful to predict the blooming date of 'Yumyeong' peach trees.

• The Korea Swine Journal
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• v.18 no.6 s.202
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• pp.166-171
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• 1996

여름철이 되면 평균 기온이 27도씨이상 되는 무더운 날씨가 계속되고 장마로 인하여 습도가 높아지면 불괘지수가 높아져서 관리자들도 모든 일이 짜증스럽고 주위가 산만해지기 쉬운 계절이다. 또한 여름철에는 양돈장에 파리와 모기 등의 해충이 많이 발생하고 유해 가스가 많이 생기며 사료가 쉽게 변질되는 등으로 돼지의 사육에 직접 간접으로 불리하게 미치는 영향이 커서 발육이나 번식 능력을 떨어뜨리게 된다. 특히 돼지는 선천적으로 다른 가축에 비하여 땀샘이 퇴화되고 피하지방이 두껍고 체지방축적이 많은 관계로 더위에 매우 약하므로 무더움 여름철에는 신진대사와 호르몬 분비 조절기능이 비정상적인 경우가 많아 사료섭취량 감소, 발육 지연 및 번식 성적에 관련되는 발정, 배란, 수태율, 산자수 등이 감소하게 된다. 따라서 무더운 날씨가 계속되는 여름철에는 다른 계절보다 돼지의 사육에 적합한 온도, 습도, 환기 등에 많은 관심을 기울여서 쾌적한 사육 환경을 조성하여 생산성을 높일 수 있도록 하고 그 중에서도 여름철에 돼지의 수태율을 향상시킬 수 있는 관리 대책을 강구해야겠다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.202-208
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• 2001

Under the constant daylength of 13 hours and growth temperatures of 15$^{\circ}C$ to 27$^{\circ}C$, the final number of loaves (FNL) on the main culm was constant as 15 regardless of temperature in rice variety 'Kwanganbyeo'. Leaf appearance rate (LAR) increased with rising temperature and decreased with phenological development. Threshold temperature (T$_{o}$) was not constant across growth stages, but increased with phenological development. Effective accumulated temperature (EAT), which is calculated by the summation of values subtracting T0 from daily mean temperature, is closely related with number of leaves appeared (LA). LA was fitted to bilinear, quadratic, power and logistic function of EAT. Among the functions, logistic function had the best fitness of which coefficient of determination was $R^2$=0.995. Therefore, LAR prediction model was established by differentiating this function in terms of time: (equation omitted). where dL/dt is LAR, T$_1$ is daily mean temperature, L is the number of leaves appeared, and a, b, and c are constants that were estimated as 41.8, 1098.38, and -0.9273, respectively. When predictions of LA were made by LAR prediction model using data independent of model establishment, the observed and predicted LA showed good agreement of $R^2$$\geq$0.99.

• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.251-261
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• 1994

This study was conducted to get some basic information about rice plant development rate and heading ecology in various climatic conditions, growing nine varieties at three locations, Jinbu as the mountainous cool area, Suweon and Iri as the plain area for two years from 1987 to 1988. Average daily air temperature and day length from transplanting to heading date were analyzed in relation to the heading. Heading date and development rate of each variety were estimated by the Symplex method and the fitness of the model was evaluated. The results obtained as follows: Average daily air temperatures among varieties during the period from transplanting to heading ranged from 18 to $19^{\circ}C$ in Jinbu, from 22.5 to $23.5^{\circ}C$ in Suweon, and from 23.5 to $24.5^{\circ}C$ in Iri, the late-maturing varieties requiring the higher temperatures. The average heading days were about 20 days longer in Jinbu and $3{\sim}5$ days shorter in Iri than those in Suweon in all varieties. Little differences in accumulated temperature from transplanting to heading were observed in regions and years, and also among varieties. Developmental stages could be expressed as the accumulation of daily development rate and the predicted heading dates by the Symplex method were similar to the observed ones. The development rate of each variety varies with air temperatures. The early maturing Japonica types including the Unbong variety were fast in development rate at lower temperatures, but the late-maturing varieties of the Japonica type were late. A model to predict the heading dates of rice varieties by the Symplex method using air temperatures and day lengths was feasible.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.77-85
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• 2018

We surveyed 281 sites of tropical plants and 666 sites of fruit plants for three years (2015~2017) on Pseudococcus longispinus and Pseudococcus orchidicola which have not been surveyed domestically. In tropical plants, P. longispinus were found at 34 sites, while P. orchidicola were found at 87 sites. However, both species were not found in fruit plants. The developmental characteristics of P. longispinus and P. orchidicola were investigated under various temperatures. The female nymph of P. longispinus did not develop at $14^{\circ}C$ and the developmental period was the longest at $16^{\circ}C$ for 361.4 days and the shortest at $32^{\circ}C$ for 39.0 days. The longevity of female adult of P. longispinus was the shortest at $28^{\circ}C$ as 71.7 days. The number of offspring was highest at 177.7 at $32^{\circ}C$. The female nymph of P. orchidicola did not develop at $12^{\circ}C$. However, the developmental period was the longest at $14^{\circ}C$ for 184.9 days and the shortest at $28^{\circ}C$ for 21.5 days. The longevity of female adult of P. orchidicola was the shortest at 51.5 days at $28^{\circ}C$. The number of offspring was highest at 143.8 at $28^{\circ}C$. The net reproductive rate ($R_0$) and intrinsic rate of increase ($r_m$) of P. longispinus were 162.3 and 0.127 at $32^{\circ}C$, respectively. The $R_0$ and $r_m$ of P. orchidicola were 98.3 and 0.139 at $28^{\circ}C$, respectively. These results suggest that the optimum temperature of P. longispinus and P. orchidicola was $32^{\circ}C$ and $28^{\circ}C$, respectively. Therefore, we guess that they can never be able to survive the winter of Korea.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.91-97
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• 2002

This study was conducted to determine the effects of temperature and food onthe nymphal development and adult longevity of the green virid bug, Cyrtorhinus lividipennis Router. Nymphal period was 13.2 to 13.7 days at 24$^{\circ}C$, 10.4 to 10.9 days at 28$^{\circ}C$, and 9.0 to 9.3 days at 32$^{\circ}C$. Number of eggs predated by nymph was 10.6-14.3 at 24$^{\circ}C$, 7.5-9.2 at 28$^{\circ}C$, and 5.8-7.5 at 32$^{\circ}C$. Amount of predation was highest on BPH, followed by SBPH, WBPH, and GLH. Number of nympal moulting was mostly four times (55-75%) followed by three times (25-45%), regardless of temperature and food. Percent emergence rate was 52-70%, 48-66% and 22-38% at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, showing a tendency to decrease with increasing temperature, and was affected by foods. Adult longevity, when supplied with one food, was 19.8 to 22.5 days at 24$^{\circ}C$, 15.6 to 17.0 days at 28$^{\circ}C$, and 10.3 to 11.7 days at 32$^{\circ}C$. There was no significant difference among foods in terms of adult longevity, but it tended to be slightly longer when provided with four foods than with one food. Number of eggs predated by an adult, when supplied with one food, was 35.7-54.2, 31.6-44.6 and 18.1-28.2 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively. It was highest on BPH, followed by SBPH, WBPH and GLH regardless of temperature. Number of egg Predated by an adult, when supplied with four foods, was 4.0-28.9, 2.9-29.0 and 17-13.6 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, and was significantly different among foods supplied. The results suggest that the significantly different predation amount by adult was due to food preference amoung the different foods.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.42-48
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• 1984

The developments of overwintering larvae of the peach fruit moth, Carposina niponensis Walsingham, were studied in Suweon. Among fully grown larvae leaving from apple fruit, the earliest diapause larva was observed late July, about $50\%-diapause$ in middle August and $100\%-diapause$ in early September. Induction of the diapause seemed to have relationships with the time of oviposition: the incidents of the diapause started with the larvae grown from the eggs which had been laid in late June or late July depending on the prevailing weather condition. The termination of the diapause seemed to be in early December, and almost all of the larvae incubated after January were pupated. For the breakage of the diapause, it required chilling period more than one month, and the most effective temperature seemed to be $5\~10^{\circ}C$, while the temperature lower than $0^{\circ}C$ seemed to be inhibitory, if not at all. The overwintered larvae started to pupate in middle May, and the developments of the over-wintered larvae were affected by the temperature as well as the moisture contents of soil in the spring. The dry condition of soil increased the mortality of the developing larvae.