Caterpillars perceive their food's taste by a limited number of receptor cells. As is shown in several studies reported in literature, gustation plays a crucial rôle in both qualitative and quantitative aspects of feeding responses. In this thesis, a comparative investigation on gustatory perception of plant constituents in several Yponomeuta species is described.The species studied, their associated hosts and stimuli applied are shown in Table 1 of the first chapter. Electrophysiological data were obtained by means of a tip recording technique. The sensory cells respond to stimulation by generating a train of action potentials (Fig. 1, chapter 1). A model which can explain the shape and magnitude of the recorded action potentials is described in chapter 6. Routinely the number of spikes during an arbitrary interval of stimulation served as response index. In addition some of the activities were analysed in greater detail. This type of analysis, taking into account the number of activities in each recording and their time courses is described in chapters 1 and 5. Several types of interspecific sensitivity spectra have been recorded and are represented in Table 2 and Fig. 6 in chapter 1. A classification of a complete array of responses was carried out by a cluster analysis and is described in the second chapter; it appears that most species can be distinguished on the basis of functional criteria (Fig. 1, chapter 2). As far as can be determined natural concentrations (Table 1, chapter 1) appear to be situated above receptor cell threshold levels (Fig. 6, chapter 1). General aspect on relationships between receptor cell sensitivity, natural concentrations and data processing by the central nervous system are described in chapter 7. Although the vertebrate olfactory system is used to illustrate the examples in the seventh chapter, the principles described are also valid for the insect gustatory system. In larvae of Y. cagnagellus and Y. evonymellus behavioural responses to some of the stimuli used in the electrophysiological experiments were determined (chapter 3). To study inheritance of gustatory sensitivity, F1 offspring of reciprocal crosses between Y.cagnagellus and Y. malinellus was tested for sensitivity to solutions of dulcitol, phloridzin, prunasin and sorbitol (chapter 4).
|Qualification||Doctor of Philosophy|
|Award date||8 Oct 1980|
|Place of Publication||Wageningen|
|Publication status||Published - 1980|
- host preferences
- taste sensitivity