• Korean journal of applied entomology
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• v.61 no.2
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• pp.357-368
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• 2022

We investigated the developmental characteristics of super mealworm (Coleoptera: Tenebrionidae) at four different temperatures (25℃, 27℃, 30℃, and 33℃). The rearing conditions were 9L/15D, 65% RH, and 1,330 to 1,800 lux with wheat bran. The length of developmental period of 1 to 18 instars at each temperature showed that 30℃ was the shortest at 120.0±5.8 days, compared to that at 27℃ (132.6±10.7 days), 33℃ (136.5±9.2 days), and 25℃ (156.7±7.5 days). The larval developmental period was statistically significantly longer at 25℃, 27℃, and 30℃ compared to the length at 33℃. However, the death rate of larvae at 33℃ was 2.7-3.3 times higher than the rate at other temperatures. Body weight was heaviest at 30℃ followed by 27℃, 33℃, and 25℃. The patterns of head capsule, body capsule, and body length were similar to that of body weight. Regression analyses of developmental period, larval body weight, and length according to temperature revealed 29-30℃ as the most suitable temperature. The prepupa rate was 43.1% in 17 instars, 30.3% in 18 instars, 15.4% in 16 instars, 7.1% in 19 instars, 2.2% in 15 instars, and 1.9% in 20 instars, accounting for 88.8% in 16-18 instars. Prepupal period was longer at lower temperatures. For the average prepupal period of 15-18 instars, prepupa time was 18.8±1.9 days at 27℃, 18.8±2.3 days at 30℃, 23.0±2.4 days at 33℃, and 23.1±2.9 days at 25℃. The average pupal period of females and males was 11.1±2.2 and 11.6±2.4 days, respectively. The data indicate that the most suitable rearing temperature of super mealworm was 30℃.

• Korean journal of applied entomology
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• v.26 no.1 s.70
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• pp.13-23
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• 1987

This study was conducted to know the effects of temperature conditions on the growth and oviposition of the brown planthopper(BPH), Nilaparvata lugens $St{\aa}l$. Results obtained were to predict the timing of the BPH control by measuring population dynamics of the BPH in response to temperature fluctuations upon migration of the insects in paddy fields. Developmental and ovipositional rates under constant and alternating temperature conditions were observed in a plant growth cabinet. Hatchabilities of eggs of the BPH were the highest at $25^{\circ}C$ and were decreased below or above the optimum temperature. Egg periods were the shortest at $27.5^{\circ}C$ and prolonged with decreasing temperature, but retarded at higher temperature above $30^{\circ}C$. Adult emergence rates were the highest at $27.5^{\circ}C$ and reduced with decreasing temperature, and no adult emerged at $32.5^{\circ}C$ and $35^{\circ}C$. Developmental period of nymph was the shortest at both $27.5^{\circ}C$ and $30^{\circ}C$, but extended with decreasing temperature. Female longevity was increased with decreasing temperature and the male longevity was the shortest at $27.5^{\circ}C$. Preoviposition period was the shortest at $32.5^{\circ}C$, but prolonged with decreasing temperature. It was about 6.5 times longer at $17.5^{\circ}C$ than that at $32.5^{\circ}C$. Number of eggs oviposited per female was the greatest at $25^{\circ}C$, but decreased at the temperature below or above the optimum. Under the same total effective day-degrees, hatchabilty at the alternating temperature was about 10% higher than that at the constant temperature but egg period at the alternating temperature was nearly identical as that at the constant. Under the $22^{\circ}C$ condition, emergence rate was about 8% higher at the alternating temperature than that at the constant, however, at the $28^{\circ}C$, the rate was about 8% higher at the constant than that at the alternating. Nymphal period was about $4{\sim}6$ days longer at the alternating temperature than that at the constant. Under the same total effective day-degrees in adult stage, both longevity and oviposition period were longer at alternating temperature than those at the constant. Number of eggs oviposited per female was also higher at the alternating. Longevities of females reared under $28^{\circ}C$ of constant temperature was the longest no matter what temperatures they were exposed after the emergence. This result seems to be indicating that female longevity is greatly influenced by the temperature to which they were exposed durings immature stages. Preoviposition period was affected by the temperature exposed during the nympal and adult stage whereas the number of eggs oviposited was affected by the temperature during the adult stage only. Based on the results from this study, the developmental threshold temperatures seem to be $14.12^{\circ}C$ for eggs, $14.76^{\circ}C$ for nymphs, $9.62^{\circ}C$ for adults, and $15.95^{\circ}C$ for preoviposition period. Estimated values of the total effective temperature for completing each stage were 141.25 day-degrees for eggs, 167.83 day-degrees for nymphs, 349.64 day-degrees for adults, and 58.60 day-degrees for preoviposition.

• Korean Journal of Environmental Biology
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• v.27 no.3
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• pp.292-296
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• 2009

This study was conducted to estimate relationship between temperature and egg development of Nannophya pygmaea, an endangerd dragonfly species in Korea, using eight different temperature conditions (17, 20, 22, 25, 28, 30, 33, and $36^{\circ}C$). Eggs of N. pygmaea were collected from female adults inhabited a small wetland in Mungyeong-si, Gyeongsangbuk-do, Korea, in June 2007. As a result, hatching rates were 2.86, 17.09, 24.32, 39.67, 34.43, 40.57, 44.79, and 1.75% at 17, 20, 22, 25, 28, 30, 33, and $36^{\circ}C$, respectively. The nonlinear model of the temperature related to egg development was well fit to the modified Sharpe and DeMichele model. The derived lower developmental threshold temperature for egg hatching was $14.02^{\circ}C$(y=0.005988x-0.084, $r^2$=0.99), and the derived optimal development temperature was $30{\sim}35^{\circ}C$.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.431-438
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• 2012

The developmental time of the nymphs of Myzus persicae was studied in the laboratory (six constant temperatures from 15 to $30^{\circ}C$ with 50~60% RH, and a photoperiod of 14L:10D) and in a green-pepper plastic house. Mortality of M. persicae in laboratory was high in the first(6.7~13.3%) and second instar nymphs(6.7%) at low temperatures and high in the third (17.8%) and fourth instar nymphs(17.8%) at high temperatures. Mortality was 66.7% at $33^{\circ}C$ in laboratory and $26.7^{\circ}C$ in plastic house. The total developmental time was the longest at $14.6^{\circ}C$ (14.4 days) and shortest at $26.7^{\circ}C$ (6.0 days) in plastic house. The lower threshold temperature of the total nymphal stage was $3.0^{\circ}C$ in laboratory. The thermal constant required for nymphal stage was 111.1DD. The relationship between developmental rate and temperature was fitted nonlinear model by Logan-6 which has the lowest value on Akaike information criterion (AIC) and Bayesian information criterion (BIC). The distribution of completion of each developmental stage was well described by the 3-parameter Weibull function ($r^2=0.95{\sim}0.97$). This model accurately described the predicted and observed occurrences. Thus the model is considered to be good for use in predicting the optimal spray time for Myzus persicae.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.315-323
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• 2023

The brassica leaf beetle, Phaedon brassicae Baly (Coleoptera: Chrysomelidae), is one of the important pests infesting cruciferous vegetables. In order to understand the biological characteristics of the insect, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of P. brassicae at four constant temperatures of 15, 20, 25 and 27.5℃ for immature life stage and five constant different temperatures of 10, 15, 20, 25 and 27.5℃ for adult stage. Eggs and larvae successfully developed next life stage at temperature tested. The development period of egg, larva, and pupa decreased as temperature increased. Lower developmental threshold (LDT) and thermal constant (K) were calculated using linear regression as 8.7℃ and 344.73DD, respectively. Lower and higher threshold temperature (TL and TH) from egg to adult emergence were estimated by Briere function as 5.3℃ and 40.4℃, respectively. Adults produced eggs at the temperature range between 10℃ and 27.5℃, and showed an estimated maximum number, ca. 627.5 eggs at 21.7℃. Adult oviposition models including aging rate, age-specific survival rate, age-specific cumulative oviposition, and temperature-dependent fecundity were constructed. Temperature-dependent development models and adult oviposition models would be useful components to understand the population dynamics of P. brassicae and to establish the strategy of integrated pest management in cruciferous crops.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.43-47
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• 1997

This study was carried out in the laboratory to clarify effects of different temperature of Protopulvinaria mangiferae(Green) on development, survivorship and reproduction. Developmental period of the mango shieldscale from crawlers to preoviposition adult decreased as temperature increased. The threshold temperature andthermal constants for the development of one generation were 11.7"C and 1000.0 day-degrees, respectively. At25$^{\circ}$C and 30$^{\circ}$C, survival rate from egg to preoviposition adult were 82% and 6096, respectively. Hatchability ofeggs was more than 99% at both condition. The reproductive period overaged 50 days(2SnC) and 33 days(30$^{\circ}$C). After mature adult began to reporduce, and more than 50% of the crawlers emerged during the firsthalf of their life time. The net reproduction rate per generation(R), mean length of a generation0 and intrinsicrate of natural increase(r, ) were higher at 25$^{\circ}$C than at 30"C, and the values measured at 25$^{\circ}$C were 132.6, 76.2 and 0.064/female/day, respectively.

• Korean journal of applied entomology
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• v.41 no.3
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• pp.205-209
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• 2002

Effects of temperature on the development and reproduction of the Udea ferrugalis Hubner were investigated at various temperatures (10, 15, 18, 20, 23, 25, 27, 30$\^{C}$). The development times of eggs, larvae, prepupae and pupae were shorter in higher temperatures than in lower ones. Egg and pupa did not develop at 10$\^{C}$. The lower developmental threshold temperatures for eggs, larvae, pupae were 9.5, 9.6 and 11.9$\^{C}$, respectively, and their thermal requirements for development completion were 87.9, 200.9 and 119.7 degree-days at the same temperature, respectively. Adult longevity was 25.2 days at 15$\^{C}$, 7.3 at 23$\^{C}$ and 5.3 at 30$\^{C}$. Mean fecundity per female was higher at 20-23$\^{C}$ compared to other temperatures. Mean generation time in days (T) was shorter in higher temperature region. Net reproductive rate per generation (Ro) was lowest at 15$\^{C}$ (138.2) and it was highest at 20$\^{C}$ (265.4). The intrinsic rate of natural increase (r$\_$m/) was highest at 25$\^{C}$ as 0.247. As a result, it was considered that optimum range of temperature for U. ferrugalis growth was 20.0 to 23$\^{C}$.

• Korean journal of applied entomology
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• v.41 no.3
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• pp.199-204
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• 2002

Population fluctuation of O. kashmirica benefica, a major natural enemy of citrus red mite (Panonychus citri), was surveyed from 1997 to 2000 in yuzu orchards in Goheung region and, developmental periods, developmental threshold temperature (DT) and effective cumulative temperature (ET) were estimated. Under four constant temperatures of 15, 20, 25 and 30$\^{C}$, developmental periods from egg to adult of the beetles were 67.3, 31.4, 19.4 and 15.3 days, respectively. The period of each stage was long in the order of pupa> egg > 3rd larva> 2nd larva> 1st larva. Mean numbers of eggs oviposited by a female per day were 3.3, 5.6, 7.3 and 7.7 under the temperatures, respectively. The highest hatchability (92%) and adult emergence (60%) were shown under 25$\^{C}$. Adult longevity was 54.3 days for females, and 58.6 days for males. In natural condition, the sex ratio of the beetle was 0.58. Developmental thresholds (DT) for egg, 1st, 2nd, 3rd larva, pupa, and egg to adult were 12.7, 10.0, 10.8, 7.9, 10.1 and 10.6$\^{C}$, respectively. The effective cumulative temperatures (ET) were 41.4, 22.9, 22.7, 46.6, 165.3, 292.9 day-degree at the same development stage, respectively. The beetle occurred from early April to early December in yuzu orchards. The population peak of the beetles was dependent on the amount of prey mite (Panonychus citri), and the ratio of the predator to prey mite was 1 to 100-200 at predator peak stage in the field.

• 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.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.445-452
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• 2016

Exorista japonica is one of the major natural enemies of noctuid larvae, Mythimna separata and Spodoptera litura. The examined parasitoid was obtained from host species M. separata, collected at Gimje city and identified by DNA sequences (partial cytochrome oxidase I, 16S, 18S, and 28S). For purposed of this study, laboratory reared S. litura served as the host species for the development of the E. japonica. The developmental period of E. japonica immature stages were investigated at seven constant temperatures (16, 19, 22, 25, 28, 31, $34{\pm}1^{\circ}C$, RH 20~30%). Temperature-dependent developmental rates and development completion models were developed. E. japonica was successfully developed from egg to adult in $16{\sim}31^{\circ}C$ temperature regimes. Developmental duration was the shortest at $34^{\circ}C$ (8.3 days) and the longest at $16^{\circ}C$ (23.4 days) from egg to pupa development. Pupal development duration was the shortest at $28^{\circ}C$ (7.3 days). Total immature-stage development duration decreased with increasing temperature, and was the shortest at $31^{\circ}C$ (16.3 days) and the longest at $16^{\circ}C$ (45.4 days). The lower developmental threshold was $7.8^{\circ}C$ and thermal constant required to complete total immature-stage development was 370.4 degree days. Among four non-linear temperature-dependent developmental rate models, Briere 1 model had the highest adjusted R-squared (0.96). The distribution model of development completion for total immature stage development of E. japonica was well described by all model ($r^2_{adj}=0.90$) based on the standardized development duration. These results of study would be necessary not only to develop population dynamics model but also to understand fundamental biology of E. japonica.