EFFECT OF SOME ENVIRONMENTAL CONDITIONS ON DIAPUSE OF LOBES1A BOTRANA DEN AND SCHIFF (TORTRICIDAE: LEPIDOPTERA)

ABOUEI-ELA, REFAT G.; EL-HAKIM, AIDA M.; HANNA, SALWA K.; MOSALLAM, AHMED M. Z.

doi:10.21608/ejar.2003.281431

EFFECT OF SOME ENVIRONMENTAL CONDITIONS ON DIAPUSE OF LOBES1A BOTRANA DEN AND SCHIFF (TORTRICIDAE: LEPIDOPTERA)

Document Type : Original Article

Authors

¹ Department of Entomology, Faculty of Science, Cairo University, Giza, Egypt

² Plant Protection Research Institute, Agricultural Research Centre, Dokki, Giza, Egypt

10.21608/ejar.2003.281431

Abstract

The combined effect of the three weather factors (temperature, photoperiod and relative humidity) on percentage of diapaused pupae of Lobasia botrana was estimated under field conditions. Percentage of diapaused pupae were highly influenced by daily means of both temperature and photoperiod, while relative humidity had no effect on active or diapaused insects. Long days (16 L : 8 D), especially when combined with high temperature, Increased the rate of diapause development and decreased the time to subsequent adult emergence. Also, the exposure of diapaused pupae to low temperature (OM) for 15 days then reared at 25⁰0 and long photoperiod of 16 hrs. till emergence significantly shortened the pupal duration, but did not affect the pupal mortality. Diet and temperature may exert an effect on the percentage of pupae that enter diapause, however, these effects were not readily apparent except under short days less than 12 hours illumination.