1. Diapause syndrome on Gratiana boliviana Rodrigo Diaz, Bill Overholt, Julio Medal, Stephen Hight, Amy Roda, Ana Samayoa, Jorge Rosales, Ben Anuforon, Ken Hibbard

2. Background on diapause Brazilian chrysomelids on Solanum –Report of diapause during dry winter season in Brazil (23.18 o S) –Hidden in the soil under stones, dead stems and branches –Gratiana spadicea and Gratiana spp. overwinter as sexually immature adults (28- 30 o S) Florida: G. boliviana –Numbers decrease during winter Medeiros and Vasconcellos. 1994. Novel aspects of the biology of Chrysomelidae Noguiera-de-Sa et al. 2004. New developments on the biology of Chrysomelidae

3. Brazilian chrysomelids on Solanum Medeiros and Vasconcellos (1994) Novel aspects of the biology of Chrysomelidae Populations decrease during winter - four months

4. Gratiana spadicea in S. Brazil

5. Insect seasonal cycle Prediapause Peridod Diapause Induction Period Diapause Maintenance Period Postdiapause transitional Period Nondiapause Period Tauber and Tauber 1986

6. Insect seasonal cycle Prediapause Peridod Diapause Induction Period Diapause Maintenance Period Sensitive stage (s) prediapuse stage(s): neuroendocrine changes increased feeding altered growth rate accumulation of reserves diapausing stage supression of metabolism supression of growth or reproduction seasonal polyphenism seasonal migration resistance to environmental extremes Token stimulus

7. PDPDIP Diapause Maintenance Period Postdiapause Transitional Period Nondiapause Period Insect seasonal cycle all symtoms of the diapause syndrome are fully developed Phase 1-Phase 2 etc. of diapause maintenance by one or more token stimuli thermal thresholds achieve nondiapuse levels end of response to token stimuli Token stimulus for diapause termination overt manifestation (s) of development development resumes diapause color disappears cold hardiness reduced increased metabolism Token stimulus Non-Token factors Quiescence can intervene

8. Objectives Monitor population dynamics in St. Lucie Co. Determine the sensitive stage for diapause induction Determine the critical day-length for diapause induction

9. Population dynamics

10. Methodology –Transect for demographic parameters –Random collection of individuals in the hammock for dissections

11. Population dynamics Gratiana population decreases during fall, few larvae and pupae

12. Population status No clear pattern in coloration up to Oct.26 Yellow Deep green Pale green New green

14. Females New-pale green Deep green with yellow lines Note Fat Body These conditions were associated with reproductively active females

15. Males Testis Accessory gland New Mature

16. Winter sampling Hypothesis: Beetles migrate to organic matter below plant Trays containing dry TSA Mark, recapture

17. Diapause Induction

18. Diapause Induction-Photoperiod Materials & Methods –Eggs, L1, L3, L5, pupae and adults placed in growth chambers set at 25C, 60% RH –Two conditions: long days 14h and short days 10h of light –Immatures reared on TSA; one week after adult emergence, couples were placed on TSA bouquets for 20 days –Variables measured: oviposition and several internal structures

19. Diapause Induction-Photoperiod TSA bouquet

20. Diapause Induction-Photoperiod TRT ColorFat Body Digest system Hind wings Mating FemaleMale Weight mg Oocytes Weight mg Testis+A G 14:10 L:D Full ++ 22.217.03 Round ed 10:14 L:D Minimal -- 20.6417.37 Irregul ar

21. Diapause Induction-Photoperiod Adults transferred from pupae did not lay eggs Adults transferred from adult laid few eggs at the beginning of the experiment, no eggs were present after 30 days

22. Digestive System-Diapause

23. Diapause Induction-Photoperiod Preliminary results –Diapause was induced at 25 o C and 10 hours of light –Adult is the sensitive stage for diapause induction –Recommendation for winter colony maintenance: keep adults under 14h of light

24. Interaction of temperature and photoperiod

25. Temperature X Photoperiod Materials and Methods –15 couples –Photoperiod: 10, 11, 12, 13, 14 hours of light –Temperature: 15, 25, 28, 31, 34 o C –Variables measured: % of females in diapause after 20 days –Estimation of critical day-length 50 % of population enters diapause

26. Temperature X Photoperiod Results from 15 o C –None of the individuals laid eggs nor presented diapause symptoms –Temperature was too cold for sexual maturation or accumulation of fat body –TSA plants showed few signs of damage Ongoing experiment 25 o C

27. Estimation of critical day-length Better estimation of Gratiana population dynamics in southeastern USA Critical day length? 100% reproductive 100% diapause

28. Conclusions so far Population of overwintering adults is critical Gratiana overwinters as non-reproductive adult Adult is the sensitive stage for diapause induction Fourteen light hours will ensure an active colony

29. Insect seasonal cycle Prediapause Peridod Diapause Induction Period Diapause Maintenance Period Sensitive stage (s) prediapuse stage(s): neuroendocrine changes increased feeding altered growth rate accumulation of reserves diapausing stage supression of metabolism supression of growth or reproduction seasonal polyphenism seasonal migration resistance to environmental extremes Token stimulus

30. PDPDIP Diapause Maintenance Period Postdiapause Transitional Period Nondiapause Period Insect seasonal cycle all symtoms of the diapause syndrome are fully developed Phase 1-Phase 2 etc. of diapause maintenance by one or more token stimuli thermal thresholds achieve nondiapuse levels end of response to token stimuli Token stimulus for diapause termination overt manifestation (s) of development development resumes diapause color disappears cold hardiness reduced increased metabolism Token stimulus Non-Token factors Quiescence can intervene

31. The database is back!!!... when the winter starts….

32. Thanks to all of you for support and beetles! Special thanks to Jackie and Larry Markle for helping in the project!