[The photoperiodic regulation of the development and diapause of the nymphs of the taiga tick Ixodes persulcatus (Ixodidae)].

Development and diapause in nymphs of Ixodes persulcatus at the age of 12 months are regulated at 18 degrees C by day-length according to the long-day photoperiodic reaction, and regimens of engorged nymphs are of main importance. Long-day photoperiods (LD 20:4) have stimulated non-diapause development in 97-100% specimens (moulting of 50% nymphs in 67-69 days after feeding), but short-day photoperiods (LD 12:12) have induced diapause (a delay of development over than 6 months) in 75% specimens.