- 著者
- Nahoko Sota Naoki Motoyama Kenji Fujisaki Fusao Nakasuji
- 出版者
- JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY
- 雑誌
- Applied Entomology and Zoology (ISSN:00036862)
- 巻号頁・発行日
- vol.33, no.3, pp.435-440, 1998-08-25 (Released:2008-02-07)
- 参考文献数
- 22
- 被引用文献数
- 28 31
The possibility that insecticide hormoligosis might be amplified by resistance in the diamondback moth, Plutella xylostella, was tested. The fecundity of females treated with sublethal doses (LD12.5 LD25 and LD50) of fenvalerate or methomyl in the non-selected generation increased in comparison with the control group treated with acetone. The number of eggs laid by treated females in the 10th generation of the fenvalerate-selected strain, which had developed about 10, 000-fold resistance, was the same or smaller than that of the control. On the other hand, fecundity in the 8th generation of the methomyl-selected strain, which had about 4.9-fold resistance, was slightly higher in the LD12.5 and LD25 than that of control. The intensity of insecticide hormoligosis did not depend on the dose of the insecticide although a sublethal dose of the insecticides stimulated reproduction in the susceptible DBM. Furthermore, the hormoligosis was not amplified in concert with the development of resistance in the DBM.
- 著者
- Xue Dong Chen Fusao Nakasuji
- 出版者
- JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY
- 雑誌
- Applied Entomology and Zoology (ISSN:00036862)
- 巻号頁・発行日
- vol.39, no.2, pp.335-341, 2004 (Released:2004-08-25)
- 参考文献数
- 27
- 被引用文献数
- 15 16
Two populations (Replications 1 and 2) were selected for 8 generations with fenvalerate at a LD50 dose to compare the biotic performances and fitness of resistant and susceptible strains of the diamondback moth (DBM), Plutella xylostella. The LD50 value rose gradually from 1.4×10−3 μg/larva to 6.7×10−2 μg/larva in Replication 1 and to 4.9×10−2 μg/larva in Replication 2. The resistance ratio was thus 67-fold and 49-fold respectively. The eggs of the selected strain were significantly smaller than those of the non-selected strain within 2 or 3 generations, then became stabilized in Replication 1 and fluctuated in Replication 2 at 1.20×10−2 mm3. The size of the non-selected strain fluctuated around 1.35×10−2 mm3 in both replications. To investigate the genetic changes in biotic performances of DBM in the selected strain, offspring of the selected and non-selected strains were individually reared at every other generation. The survival rate of immature stages, developmental period, pupal weight, adult longevity, fecundity of females and size of eggs laid by females were compared between the two strains. The survival rate of the selected strain was significantly lower than that of the non-selected strain in the 2nd generation. The survival rate of the selected strain also tended to be lower in the other generation. The fecundity of females of the selected strain tended to be higher than in the non-selected strain. The eggs of the selected strain were significantly smaller than those of the non-selected strain in all generations. The development period, pupal weight and longevity of adults did not significantly differ between the two strains in any generation. These results suggest that successive selection with fenvalerate at a sublethal LD50 dose yielded a fitness disadvantage in the DBM population.
- 著者
- Yuki Fujiwara Tomoko Takahashi Toshie Yoshioka Fusao Nakasuji
- 出版者
- JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY
- 雑誌
- Applied Entomology and Zoology (ISSN:00036862)
- 巻号頁・発行日
- vol.37, no.1, pp.103-109, 2002 (Released:2003-04-25)
- 参考文献数
- 31
- 被引用文献数
- 49 60
Fecundity and egg size were compared in adult of the females adult diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae) treated and untreated with sublethal doses of fenvalerate in order to understand the physiological significance of insecticidal hormoligosis. The 4th stadium larvae were treated with fenvalerate at LD25 or LD50. More eggs were laid by treated females at LD25 than untreated females, although the difference was only marginally significant (p=0.07). However, the eggs laid by treated females at LD25 and LD50 were significantly smaller in size than those laid by the control. The reproductive effort (fecundity×egg size) did not differ between treated females and the control. The treatment of a sublethal dose (LD50) against the parent affected the development and survival of offspring at immature stages of males. The hatchability of smaller eggs laid by treated females at LD25 tended to be lower than those of controls under different humidity conditions, and the difference was apparent at a humidity of 29%. The survival rate of the offspring at immature stages was lower in the treatment group (LD25) than in the control group, and development tended to be prolonged in the former group at temperatures higher than 20°C.