is necessary to solve these problems. From the view-point of the
effective use of biomass as alternative fuels, many studies have
been conducted so far In these
studies, plants with high amounts of fuel components (e.g., starch,
oil and terpenes) were explored, and the combustion characteristics
of each plant were investigated. However, those studies require
enormous time and effort to survey tens of thousands of plants
worldwide.
The control of plant components is another strategy to promote
the effective use of biomass. Plant growth conditions are
potential parameters that can be used to optimize the plant components.
For example, the amounts of vitamins and amino acids in
plants can be changed by varying the temperature and amount of
water in the growth environment
Plants tend to accumulate stress metabolites such as glutathione
and polyamines when they are exposed to drought stress Temperature can also be used to modulate the levels
of hormones, primary and secondary metabolites, although a
high temperature may adversely affect photosynthesis, respiration,
water relations and membrane stability The control of these environmental factors in a closed system has been
studied to improve the quality of plants and to increase their growth