TERMINATION OF PUPAL DIAPAUSE IN THE BOLLWORM HELICOVERPA ARMIGERA BY PRECOCENE II

AbstractHelicoverpa armigera (Hübner) exhibits a facultative pupal diapause, which depends on temperature and photoperiod. Pupal diapause is induced at 20°C by short photoperiods and inhibited by long photoperiods during the larval stage. However, in some pupae (35% of males and 57% of females) of a non-selected field population from Okayama Prefecture (34.6°N), diapause is not induced by short photoperiods. In the present experiment, the importance of temperature for diapause induction was studied in the non-diapausing strain, which was selected from such individuals reared at 20°C under a short photoperiod of 10L:14D. Furthermore, the sensitive stage for thermal determination of pupal diapause was determined by transferring larvae of various instars and pupae between 20°C and 15°C. Diapause was induced by 15°C without respect to photoperiod. When larvae or pupae reared from eggs at 20°C under a short or a long photoperiod were transferred to 15°C in the periods of the middle fifth instar to the first three days after pupation, the diapause induction rate was significantly reduced in both males and females, especially in females. In contrast, when larvae or pupae reared at 15°C were transferred to 20°C in the same periods, diapause was induced in males, but not in females. However, the diapause induction rate of pupae transferred to 20°C on the fourth day after pupation was significantly increased in females. The results show that temperature is the major diapause cue in the photoperiod-insensitive strain and the periods of middle fifth larval instar to early pupal stage are the thermal sensitive stages for pupal diapause induction with some different responses to temperatures between males and females in H. armigera.

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Global Metabolomic Analyses of the Hemolymph and Brain during the Initiation, Maintenance, and Termination of Pupal Diapause in the Cotton Bollworm, Helicoverpa armigera

PLoS ONE ◽

10.1371/journal.pone.0099948 ◽

2014 ◽

Vol 9 (6) ◽

pp. e99948 ◽

Cited By ~ 14

Author(s):

Yu-Xuan Lu ◽

Qi Zhang ◽

Wei-Hua Xu

Keyword(s):

Helicoverpa Armigera ◽

Cotton Bollworm ◽

Helicoverpa Armígera ◽

Pupal Diapause

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Cloning and expression of the cDNA encoding the FXPRL family of peptides and a functional analysis of their effect on breaking pupal diapause in Helicoverpa armigera

Journal of Insect Physiology ◽

10.1016/j.jinsphys.2003.09.006 ◽

2004 ◽

Vol 50 (1) ◽

pp. 25-33 ◽

Cited By ~ 65

Author(s):

Tian-Yi Zhang ◽

Jiu-Song Sun ◽

Liu-Bin Zhang ◽

Jin-Liang Shen ◽

Wei-Hua Xu

Keyword(s):

Functional Analysis ◽

Helicoverpa Armigera ◽

Cloning And Expression ◽

Helicoverpa Armígera ◽

Pupal Diapause

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Effect of photoperiod and temperature on the intensity of pupal diapause in the cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae)

Bulletin of Entomological Research ◽

10.1017/s0007485313000266 ◽

2013 ◽

Vol 104 (1) ◽

pp. 12-18 ◽

Cited By ~ 17

Author(s):

Chao Chen ◽

Qin-Wen Xia ◽

Shu Fu ◽

Xian-Fu Wu ◽

Fang-Sen Xue

Keyword(s):

Helicoverpa Armigera ◽

Adult Emergence ◽

Cotton Bollworm ◽

Day Length ◽

Natural Conditions ◽

Developmental Threshold ◽

Rearing Temperature ◽

Helicoverpa Armígera ◽

Pupal Diapause ◽

Diapause Development

AbstractThe intensity of pupal diapause in the cotton bollworm, Helicoverpa armigera (Hübner) was investigated under both laboratory and natural conditions. By transferring diapausing pupae induced under LD 11:13, LD 12:12 and LD 13:11 at 20, 22 and 25 °C to 25 °C combined with LD 15:9 to terminate diapause the rearing day length of 11 h evoked greater intensity of diapause than did 12 and 13 h at 25 °C; whereas the rearing temperature of 25 °C evoked more intense diapause than did 20 and 22 °C under LD 11:13. By transferring diapausing pupae induced under LD 12:12 at 20 and 22 °C to six temperatures of 18, 20, 22, 25, 28 and 31 °C combined with LD 15:9 to terminate diapause, the duration of diapause was significantly shortened from 146 days at 18 °C to 24 days at 31 °C, showing that high temperatures significantly accelerate diapause development. Furthermore, the duration of diapause was significantly longer at the rearing temperature of 22 °C than that at 20 °C when the diapause-terminating temperatures were 20 and 22 °C. Chilling at 5 °C did not shorten the duration of diapause but lengthened it when chilling period was included. However, chilling plays an important role in synchronizing adult emergence. Rearing temperature of 22 °C also evoked more intense diapause than did 20 °C in most chilling treatments. When the overwintering pupae were transferred at different times from natural temperatures to 25 °C, it was found that the earlier the transfer took place, the earlier the adults emerged when the time spent under natural conditions was included. However, cool temperatures before March showed an enhanced effect on diapause development at 20 °C, suggesting that the high diapause-terminating temperature can offset the effect of chilling on diapause development. The result of diapause termination under natural conditions suggests that the developmental threshold for post-diapause development in H. armigera should be around 17.5 °C.

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