Most plants have hairs on their aerial surfaces, superficially
similar to the hairs on the human body. These plant hairs, or
trichomes, affect the plant in a number of ways. It has been
suggested that plant hairs can change the optical properties of
the leaf surface and could help to conserve heat and/or moisture.
There are two main types of trichomes: glandular and nonglandular.
Glandular trichomes contain or secrete a mixture of
chemicals that have been found to have an enormous array of
uses in the pesticide, pharmaceutical, and flavour/fragrance
industries. Besides these industrial uses, glandular trichomes
on some crop species confer resistance against insect pests.
Thus, there is today an increasing interest in understanding the
chemistry of glandular trichome exudates and taking advantage
of their potential uses.