• Korean journal of applied entomology
• /
• v.38 no.2
• /
• pp.129-138
• /
• 1999

This study was carried out with two types of silkworm, Bombyx mori, adults having different life span: long life span (adult living for more than fifteen days; LLS), and short life span (adult living less for than five days; SLS). The fine structures of fat body cells in the young and the senescent males and females were compared in an attempt to elucidate the aging physiology of the silkworm adult. In SLS, there were many rough endoplasmic reticula (RER) and glycogen granules in the female cytoplasm, whereas the smooth endoplasmic reticula (SER) were observed in the male cytoplasm. Also in SLS, the mitochondria were swollen and had many poor osmiophillic inclusions (fatty degeneration) at three days after emergence. In LLS, compared to SLS, comparatively normal mitochondria and nuclear membrane were observed in even five day old female. In fifteen day old LLS female, however most of cell membranes were disappeared and mitochondria were abnormally expanded. Many fat granules were observed in the cytoplasm of ten day old male (LLS) which died with full autophagic vacuole (AV) collapsed at fifteen days. Therefore, it is suggested that SLS type is recommended for the study of aging tissue, because it is easier to monitor the changes in tissue structure.

• Korean journal of applied entomology
• /
• v.38 no.3
• /
• pp.225-230
• /
• 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
• /
• v.12 no.4 s.17
• /
• pp.153-155
• /
• 1973

1. 침파리의 동계사육 결과 평균온도 $23.7^{\circ}C$에서 유충기간 7일, 용기간 9.2일, 전산란기간 14.2일, 성충수명 23.3일이었다. 2. 5월부터 7월까지 사육온도 $25\pm1^{\circ}C$로 고정시켰을 때의 생육기간은 유충기간 8.0일, 용기간 5.3일, 전산란기간 11.7일, 성충수명 30.1일 이었다. 3. 용 개체중량은 5월-7월의 $25\pm1^{\circ}C$에서 13.3mg으로서 현저한 증가를 볼 수 있었다. 4. 전산란 기간중의 성충사망율은 습도 조절(R. H.)에 따라서 큰 차이를 보여주었으며 누대사육을위해서는 $55-65\%$의 R.H.를 유지할 필요가 있을 것으로 본다. 5. 성충의 산란율은 산란 시작후 제8-10일에 제일 높다.

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2003.10a
• /
• pp.128-128
• /
• 2003

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2003.10a
• /
• pp.129-129
• /
• 2003

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

• Korean journal of applied entomology
• /
• v.43 no.4 s.137
• /
• pp.275-279
• /
• 2004

This study compared the biological characteristics, nymphal development, adult longevity, and oviposition of the bean bug, Riptortus clavatus Thunberg, in fibrous nylon and glass-tube in the insectary at $28{\pm}2^{\circ}C$ and 16L:8D of photoperiod. Nymphal duration in the fibrous nylon-tube was 1 day longer than in the glass tube; the difference was attributed to the developmental duration of the fifth instar. Percent emergence in the fibrous nylon-tube was $64\%,\;8\%$ higher than in the glass tube ($56\%$). In the fibrous nylon-tube, adult longevities for female and male were 4.1 times and 6.0 times higher than those in the glass tube. Preoviposition period was 1 day longer in the fibrous nylon-tube than that in the glass tube. The total number of eggs laid was 3.5 times more in the fibrous nylon-tube than in the glass tube. The oviposition duration lasted about 30 days for the bean bug in the fibrous nylon-tube and about 8 days for those in the glass. Accordingly, the fibrous nylon-tube was found more conducive than the glass tube for determining the biology of bean bug.

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

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2002.05a
• /
• pp.114-114
• /
• 2002

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2003.10a
• /
• pp.127-127
• /
• 2003