Plant growth is affected by environmental changes such as
extreme temperature, water shortage, insufficient or excess light
and nutrient limitation. Several environmental factors are associated
with metabolism (Smirnoff, 1995) and thereby alter the
composition and concentration of plant chemical compounds.
Hornok (1986) showed that the same plant species cultivated at
different locations or during different seasons possessed different
quantities of secondary metabolites. Similarly, differences were
reported for the curcuminoid and volatile oil content of turmeric
grown in different areas (Chavalittumrong and Jirawattanapong,
1992). Visuttipitakul et al. (1997) reported that cassumunar
ginger grown at Kanchanaburi and harvested 10 months after
planting contained 1.10% volatile oil based on fresh weight
with the major components sabinene (45.22–47.86%), terpinen-
4-ol (20.51–21.43%) and DMPBD (10.12–11.68%). According to
Aengwanich (2002), cassumunar ginger grown in Khon Kaen
Province and harvested 18 months after planting contained 3.49%
volatile oil, and terpinen-4-ol represented 24.23% of the volatile oil
based on fresh weight.