MAIN FEATURES OF PHOTOPERIODIC REACTION IN DERMACENTOR MARGINATUS SULZ. TICKS (IXODOIDEA),
Abstract
In Dermacentor marginatus females (Daghestan population) the dependence of the oviposition delay at 18C upon photoperiodical and temperature conditions of their maintenance prior to feeding was investigated. The delay of egg-laying represents winter diapause and is determined by both light and temperature conditions of maintenance of hungry ticks in correspondence with the norm of short-day photoperiodical reaction. Long day brings about prolonged delay (oviposition starts not earlier than after 4 months), while a short-day stimulates the non-diapause oviposition. 14 hrs. of light p.d. is of crucial significance. No shift of the threshold occurs with a change in temperature. A peculiarity of photoperiodical reaction in Dermacentor marginatus consists in a dependence of the duration of the delay within the short-day range upon light and temperature conditions of maintenance of hungry ticks, as well as upon their age. The photoperiod of 9 hrs. of light p.d. and the temperature of 18C are most effective in the induction of the shortest non-diapause ovogenesis (oviposition starts in 15.5 days). A change in the day length and a temperature increase (up to 25C) induce a prolongation of the delay (at 14 hrs. of light and 25C the delay increases 8.1 times). Conditions of maintenance of hungry ticks do not effect either the time of parasitizing or the weight of satiated females, but effect mortality of these latter which attains its maximum (42-60%) at threshold photoperiods and at 18C. The ecological role of these peculiarities is discussed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1963
- Accession Number
- AD0660153
Entities
People
- N. V. Kvitko
- V. N. Belozerov
Organizations
- Naval Medical Research Center