Alkaloids and Taste in Insects

In insects the perception of taste is particularly interesting both from the theoretical point of view and for practical applications. Insects have very efficient gustative organs not only in the mouth but also in legs, antermae, in the abdominal region, and even in the internal stomach. 

Many excellent books and reviews [63-67] describe this complex system and the role of insect taste in ecology, agriculture, and in the discovery of new molecules to be used as antifeedants, including many alkaloids, and only some relevant points will be summarized here. 

Since the genome of Drosophila spp. is completely known, taste in this insect has also been investigated by using flies with some genes - corresponding to the neurons 

Gr5a and Gr66a - ablated by genetic manipulation. Taste responsiveness was assessed by performing proboscis extension reflex assays in control and DTI expressing animals. 

In a second experiment, leaves from the previous experiment vere offered to new cohorts of A. gemmatalis larvae, for 24 h. Rumbo vas the most palatable variety vhen 

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