Terpenes are supposed to be mainly responsible for smell and flavor. I found this thread interesting
Terpenes in cannabis - the Green House Seed Co. approach.This info apparently comes from a breeder. Some info hear sounds similar to somethings learned in school and things I read that Ed Rosenthal wrote.
"Over 100 terpenes have been identified in marijauna. There are actually many more when one considers the multiple variations of each terpene. For instance, the characteristic citrus odor found in fruit rinds differs by type and even variety of fruit-- oranges and lemons have different odors, and their terpenes -- called limonenes -- are mirror version of each other. Even different varieties of orange differ in their distinct odor. This is due to slight differences in the amounts of or form if limonenes, as well as other compounds that have citrus elements....Terpenes are constantly being produced but they evaporate under pressure from sunlight and rising temperatures. Plants have more terpenes at the end of the dark period than after a full day of light. You can test this yourself. Check a plants odor early in the morning and at the end of a sunny day. You will find more pungency early in the morning." (Big Book of Buds 3 Ed Rosenthal 97,98). Interesting section of the book. He later goes on to speak about 10 specific terpenes and covers what affect they have on flavor and aroma.