• Journal of Life Science
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• v.10 no.1
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• pp.1-6
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• 2000

Larval development, adult longevity and oviposition of the beet armyworm, Spodoptera exigua H bner was studied at 16, 20, 25 and 3$0^{\circ}C$ with a 16L: 8D photoperiod. Egg hatchability of S. exigua was the highest at 3$0^{\circ}C$ and reduced with decreasing temperature. Egg period was the shortest at 3$0^{\circ}C$ and prolonged with decreasing temperature. Percent pupation was became higher at higher temperature form 23.2% to 94.0%. Developmental period of larva was the shortest at 3$0^{\circ}C$, but extended with decreasing temperature. Adult emergence ratio was the highest at 3$0^{\circ}C$ and reduced with decreasing temperature. The mean pupal period was 35.2, 14.4, 7.8 and 5.0 days at 16, 20, 25 and 3$0^{\circ}C$, respectively. Relationships between constant temperature and the developmental velocity of egg, larva and pupa were linear. Developmental threshold temperature seems to be 13.3 8$^{\circ}C$ for egg, 14.02$^{\circ}C$ for larva, 14.09$^{\circ}C$ for pupa, and 13.84$^{\circ}C$ for egg the adult. Estimated value of the total effective temperature for completing each stage was 36.89 day-degree for egg, 155.72 day-degree for larva, 79.20 day-degree for pupa, and 273.41 day-degree for egg to adult. Female longevity varied to temperature from 11.4 days at 16$^{\circ}C$ to 5.8 days at 3$0^{\circ}C$, and male longevity was longer than that of female. Preoviposition period was the shortest at 3$0^{\circ}C$, but prolonged with decreasing temperature. It was about 2.7 times longer at 16$^{\circ}C$ than that at 3$0^{\circ}C$. Number of eggs per female was the highest at $25^{\circ}C$, followed by 20, 30 and 16$^{\circ}C$.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.225-230
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• 1999

This study was conducted to determine the effect of pupal development and adult longevity of Spodoptera litura larvae reared on leaves of different leguminos plants of 11 varieties or cultivars. Pupal duration varied from 8.7 to 9.5 days depending upon different diets and duration of female pupa (8.3~9.1 days) was about 1 day shorter than that of male's (9.4~10.1 days). Prepupal an postpupal duration were 1.7 to 2.0 days and 6.7 to 7.7 days, respectively. Pupal weight ranged from 0.23g to 0.43g for female and 0.24g to 0.35 g for male. Percent change of pupal weight was lowest (11%) on geomjeongkong-1 and highest (16%) on bukwangkong. Adult longevity was in ranging from 7.8 days on dongbu to 11.2 days on bukwangkong and tended to become slightly longer in female than tin male. Significant relationships were recognized between moisture content of feeding leaf, the pupal duration and weight and adult longevity.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.175-180
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• 2004

This study was conducted to determine the effect of sublethal concentrations ($LC_{10}$ and $LC_{30}$) of insecticides on pupal duration, emergence, adult longevity and oviposition of tobacco cutworm, Spodoptera litura Fabricius, when 3rd instar larva of tobacco cutworm was treated with insecticides of chlorpyrifos, ethofenprox, chlorfenapyr-bifenthrin and hexaflumuron-chlorpyrifos . Pupal duration of female and male were 6.9 days and 8.0 days at untreatment, and were 7.2 to 7.6 days and 8.3 to 8.6 days at insecticide treatment, respectively. Thus pupal duration at the insecticide treatment was slightly longer than that at the untreatment, and that of the males was slightly longer than that of the females even though significant difference between sublethal concentrations and among insecticides was not observed. Percent mergence was 88％ at untreatment and ranged from 79％ to 95％, in particular which showed above 91％ treated with chlorfenapyr-bifenthrin and ethofenprox, at insecticide treatment. Adult longevity was 7.7 days and 7.9 days for female and male at untreatment respectively, and 7.1 to 8.4 days for female and 7.7 days to 9.0 days for male at treatment. There was a significant difference between insecticides and sublethal concentrations of insecticides except showed the longest adult longevity at hexaflumuron-chlolfyrifos treatment. Total number of eggs laid were less at treatment (778-948) than that (1,010) at untreatment regardless of sublethal concentrations of insecticides. Accordingly the pupal duration and oviposition of tobacco cutworm were affected at the insecticide treatment of sublethal concentration.

• Toxicological Research
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• v.24 no.4
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• pp.245-251
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• 2008

Dietary restriction (DR) is the most efficacious intervention for retarding the deleterious effects of aging. DR increases longevity, decreases the occurrence and severity of age-related diseases, and retards the physiological decline associated with aging. The beneficial effects of DR have been mostly studied in non-neuronal tissues. However, several studies have showed that DR attenuate neuronal loss after several different insults including exposure to kainate, ischemia, and MPTP. Moreover, administration of the non-metabolizable glucose analog 2-deoxy-D-glucose (2DG) could mimic the neuroprotective effect of DR in rodent, presumably by limiting glucose availability at the cellular level. Based on the studies of chemically induced DR, it has been proposed that the mechanism whereby DR and 2DG protect neurons is largely mediated by stress response proteins such as HSP70 and GRP78 which are increased in neurons of rats and mice fed a DR regimen. In addition, DR, as mild metabolic stress, could lead to the increased activity in neuronal circuits and thus induce expression of neurotrophic factors. Interestingly, such increased neuronal activities also enhance neurogenesis in the brains of adult rodents. In this review, we focus on what is known regarding molecular mechanisms of the protective role of DR in neurodegenerative diseases and aging process. Also, we propose that DR is a mild cellular stress that stimulates production of neurotrophic factors, which are major regulators of neuronal survival, as well as neurogenesis in adult brain.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.146-152
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• 1996

The adult of the aphidophagous ladybeetle, Harmonia axyridis, was reared by feeding an artificial diet (chicken's 1iver:sugar = 5:2, v/w). The adult ladybeetle used was from pupae collected in the field in midJuly. Yolk protein production, fecundity and longevity of the adult female were checked under 3OoC, 16L:8D. Yolk proteins (Vg3 and Vg4) were detected from the hemolymph of the female 5 days after the emergence. One hundred pairs of female and male were reared separately. First oviposition started from 7 days afier the emergence and laid an average of 163.9k144.0 eggs during lifetime. Seventeen females did not lay eggs at all. Longevity of the female was 60.6k16.9 days. The application of a JH analog, methoprene (2.5 pg), caused the occurrence of yolk proteins in the hemolymph 1 day earlier than that of the control. Weekly application of 2.5 pg of methoprene induced 83.3% from the 30 females to lay eggs within 15 days after the emergence, while the control had 51% only. Methoprene made all females lay eggs, causing the increase in the fecundity. Though the longevity of the female was not effected by the weekly application of methoprene, one time excess dose (12.5 pg) caused high in mortality and low in fecundity.

• Korean journal of applied entomology
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• v.58 no.1
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• pp.77-83
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• 2019

This study was conducted to investigate the developmental characteristics of Propylea japonica Thunberg (Coleoptera: Coccinellidae) and its consumption of Myzus persicae nymphs at 3 constant temperatures (20.0, 25.0 and $30.0^{\circ}C$; $60{\pm}5%$ relative humidity; 14 h light : 10 h dark). The longevity of adult female P. japonica under 20, 25, and $30^{\circ}C$ was 134.0, 101.0 and 55.2 days, respectively. The total fecundity was 508.6, 875.6, and 383.4 eggs during its life span, respectively. The longevity of adult male P. japonica under 20, 25, and $30^{\circ}C$ was 128.8, 97.8, and 46.5 days, respectively. Average daily consumption of adult M. persicae by 1st, 2nd, 3rd, and 4th instar P. japonica at $25^{\circ}C$ was 2.2, 7.3, 14.5, and 29.1, respectively. The average daily number of M. persicae consumed by male and female P. japonica over their lifetimes was 35.0 and 42.9, respectively. Average daily consumption of adult Aphis gossypii by 1st-4th instar P. japonica at $25^{\circ}C$ was 2.2, 7.5, 13.9, and 29.5, respectively. The average daily number of A. gossypii consumed by male and female P. japonica over their lifetimes was 37.0 and 40.8, respectively.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.563-575
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• 2022

Maruca vitrata is one of important pests in leguminous crops, especially red bean. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. vitrata for understanding the biological characteristics of the insect species at eight constant temperatures of 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected and larvae successfully developed to the adult stage from 16℃ to 31℃. The developmental period of egg decreased up to 31℃ and after then increased. The developmental period of larva and pupa, and adult longevity of M. vitrata decreased with increasing temperature. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. vitrata were estimated by linear regression as 12.8℃ and 280.8DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 14.2℃ and 31.9℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. vitrata was 17.7℃. In addition, we constructed the oviposition models of adult, using the investigated adult traits including survival, longevity, oviposition period and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M vitrata and to establish the strategy of integrated pest management in legume crops.

• Korean Journal of Adult Nursing
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• v.23 no.3
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• pp.221-234
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• 2011

Purpose: The purpose of this study was to identify and describe phenomenological structures of the experiences of dietary life on elderly over 100 years old. Methods: The participants of this research included nine persons over the age of 100 years of age and ten family members who assisted in the dietary regime. Qualitative data were collected by individual in-depth interviews. Data were analyzed using Colaizzi's method of phenomenology. Results: The results of the research provide four categories and nine theme clusters. The categories included a rustic menu consisting of vegetables, grain-oriented traditional food, sensible dining table in harmony with nature, dietary life and emphasis on how to eat. The nine theme clusters were preference for fresh vegetable, preference of cooked potherb, boiled rice and cereal as main staple food, intake of soybeans, preference of native local foods, non-preference of unhealthy foods, select healthy and control food portion sizes for longevity, objection to light eating, and enjoying a meal. Conclusion: The findings of the study offer insight about the nutrition patterns among the people over 100 years of age.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.262-270
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• 1983

The newly hatched nymphs of brown planthopper(BPH) were reared individually for two generations in test tubes, where young rice seedling was planted on agar solution, at $30^{\circ}C,\;25^{\circ}C\;and\;20^{\circ}C\;with\;95\%,\;75\%,\;65\%\;and\;35\%$ R.H. Effects of $30^{\circ}C$ on the development of BPH when compared with those of $25^{\circ}C$ are followings. Egg period, nymphal period, and adult longevity were shortened. Nymphal mortality was increased and the number of oviposited eggs was decreased. Hatchability was zero per cent because the eggs were either unfertilized or died before finishing the development. At the low temperature of $20^{\circ}C$, in comparision with $25^{\circ}C$, the developmental period of nymphs and eggs was considerably lengthened, and adult longevity was shortened, the number of oviposited eggs was decreased. The nymphal mortality was higher at high relative humidity $(above\;75\%\;RH)$ than that at low relative humidity $(under\;65\%\;RH)$. Under the condition of high relative humidities, the adult longevity was shortened, and the number of oviposited eggs was decreased.

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.167-173
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• 1999

Survival analysis with life span of silkworm moth was investigated from 277 varieties preserved and maintained in Korea. Ten varieties showed long and short life span were selected for the investigation of the longevity in response to mating and surviving. The density distributions of average life span of female and male in all varieties used was 8.3days about 13%. The frequency of average survival according to life span survived 178 varieties(64.3%)for 5-10 days in male, but the female was survived 147 varieties(53%) for 10-15days. Average longevity of unmated female and male were respectively 9.5days and 9.0 days, and female survived 0.5 days longer than male. On the other hand, average longevity of mated female and male were 8.8 days and 7.7 days, respectively. It was found that mating activities affected significantly to the adult life span, especially to that of males than that of females.