292 Naturwissenschaften 86 (1999) Q Springer-Verlag 1999 ments of deaf and blind children. Nerven- arzt 65 : 598–601 Pöppel E (1985) Time perception. In: Held R, Leibowitz H, Teuber HL (eds) Hand- book of sensory physiology, Vol VIII per- ception (pp 713–729). Springer, Berlin Hei- delberg New York Schelde T (1998) Major depression: Behavio- ral markers of depression and recovery. J Nerv Ment Disord 186 : 133–140 Schleidt M (1988) A universal time constant operating in human short-term behavior repetitions. Ethology 77 : 67–75 Schleidt M, Eibl-Eibesfeldt I, Pöppel E (1987) A universal constant in temporal segmentation of human short-term behav- ior. Naturwissenschaften 74 : 289–290 Schleidt M, Kien J (1997) Segmentation in behavior and what it can tell us about brain function. Hum Nat 8 : 77–111 Snaith RP, Hamilton M, Morley S, Humayan A, Hargreaves D, Trigwell P (1995) A scale for the assessment of hedonic tone – the Snaith-Hamilton Pleasure Scale. Br J Psychiatry 167 : 99–103 Sobin C, Sackeim HA (1997) Psychomotor symptoms of depression. Am J Psychiatry 154 : 4–17 Ulrich G, Harms K (1985) A video analysis of the nonverbal behaviour of depressed patients before and after treatment. J Af- fect Disord 9 : 63–67 Wing AM (1992) The uncertain motor sys- tem: Perspectives on the variability in movement. In: Meyer DE, Kornblum S (eds) Attention and performance XI. Sy- nergies in experimental psychology, artifi- cial intelligence and cognitive neuroscience (pp 709–744). MIT Press, Cambridge Von Zerssen D (1986) Clinical self-rating scales (CSRS) of the Munich Psychiatric Information System (PSYCHIS), Münch- en. In: Sartorius N, Ban A (eds) Assess- ment of depression. Springer, Berlin Hei- delberg New York Naturwissenschaften 86, 292–294 (1999) Springer-Verlag 1999 Identification of sex pheromone components of the pea midge, Contarinia pisi (Diptera: Cecidomyiidae) Ylva Hillbur, Peter Anderson, Heinrich Arn, Marie Bengtsson, Jan Löfqvist Department of Plant Protection Sciences, Swedish Agricultural University, P.O. Box 44, S-23053 Alnarp, Sweden Anthony J. Biddle Processors and Growers Research Organisation, Thornaugh, Peterborough, PE8 6HJ, UK Olof Smitt, Hans-Erik Högberg Department of Chemistry, Mid-Sweden University, S-85170 Sundsvall, Sweden Ernst Plass, Stephan Franke, Wittko Francke Institute of Organic Chemistry, University of Hamburg, D-20146 Hamburg, Germany Received: 12 November 1998 / Accepted in revised form: 26 january 1999 Correspondence to: Y. Hillbur (e-mail: ylva.hillbur6vsv.slu.se) Abstract Three components in ex- tract of pheromone glands of female pea midges, Contarinia pisi, were found to be active on male pea midge antennae by coupled gas chromato- graphic-electroantennographic detec- tion. The EAD active components were identified as 2-acetoxytridecane, (2S,11S)-diacetoxytridecane, and (2S,12S)-diacetoxytridecane. A blend of these compounds proved to be highly attractive to males in windtun- nel experiments. The pea midge, Contarinia pisi Winn. (Diptera: Cecidomyiidae), is a serious pest reducing the yield and quality of commercial peas (Thygesen 1971; Wall et al. 1994; Pillon and Thieuleux 1995). One of the major difficulties in pea midge control is to accurately predict emergence and flight period of the adults (Wall et al. 1994). Wall et al. (1985) showed the presence of a female sex pheromone in the pea midge and concluded that this could be used for monitoring. Information on the chemistry of sex pheromones within the family Cecidomyiidae is scarce. (2S)-(E)-10-Tridecen-2-yl ace- tate has been identified in the Hes- sian fly, Mayetiola destructor (Foster et al. 1991). We have now identified similar compounds as sex pheromone components in female pea midges. Several tons of soil were collected in the United Kingdom and France to obtain cocoons with overwintering larvae. The cocoons were separated from the soil with water using a siev- ing method (Doane et al. 1987), and the adults were allowed to emerge at L/D 18/6, 257 C, and RH 70%. Hex- ane extracts of excised ovipositors of adult females proved to be highly at- tractive to males, as shown previously for calling females (Hillbur and Löfq- vist 1996). The same was true for col- lected effluvia. Gas chromatograms of extracts and effluvia consistently showed two female specific peaks (2 and 3) which elicited clear responses in male antennae when extracts of ovipositors were analysed by coupled gas chromatographic-electroantenno- graphic detection (GC-EAD; Arn et al. 1975; Fig. 1a). Figure 1a also shows an EAD response elicited by com- pound 1 eluting at an earlier reten- tion time, where no peak in the flame ionization detector signal was visible. Analyses of EAD-active components