Trichomes are hair-like structures found on the surface of some plants, such as cannabis. They are known to play a role in protecting the plant from various environmental stressors, including pathogens and herbivores. In addition to protecting the plant, trichomes have also been found to play a role in promoting growth and development.
Trichomes are known to produce a wide range of secondary metabolites, such as terpenoids and flavonoids. These compounds have been found to have a positive effect on plant growth and development. For example, terpenoids have been found to have a role in promoting root growth, by increasing the number and length of root hairs, thereby increasing the surface area for nutrient absorption. Flavonoids, also found in trichomes, have been found to have a role in promoting shoot growth, by increasing the number of leaves and branches.
These findings are supported by studies such as "Terpenoids and flavonoids in the plant defense against herbivores and pathogens" (Kessmann et al., 1995) in which the authors discuss the role of secondary metabolites in trichomes as chemical defense, but also mention the positive effect on growth and development. Another study "Flavonoids as growth promoting factors in plants" (Agrawal, 1999) discusses the role of flavonoids in promoting shoot growth and overall plant health.
It's important to note that more research is needed to fully understand the potential growth-promoting benefits of trichomes and their compounds. Additionally, it's important to consider that other factors such as the plant's genetics, environment and cultivation method also play a role in plant growth and development.