Environmental factors such as water, temperature and light also
significantly affect the concentration and composition of chemical
compounds in plants. Baher et al. (2002) reported that water stress
decreased plant height and the total fresh and dry weights of cultivated
Satureja hortensis L., whereas a mean leaf water potential
decrease from −0.5 to −1.6MPa led to the increased accumulation
of oil at the flowering stage. Compared with moderate water
stress, severe water stress had a greater effect on the quantity of
essential oils produced during both the vegetative and flowering
stages. Wang and Lincoln (2004) reported the effect of light intensity
on Myrica cerifera growth and development; light intensity
was positively correlated with the growth rate, density of glandular
trichromes, and monoterpene content.