Agriculture Reference
In-Depth Information
3.
E
NHANCEMENT OF
C
ROP
P
HOTOSYNTHESIS
The experimental results showed that nano-TiO
2
sol could form perfectly
adhesive, transparent, continuing and stable films on the surfaces of leaves, by
which net photosynthetic rate and activity of root system had been
significantly promoted [16]
．
In addition, content of photosynthetic pigment in
leaves were significantly increased when they are coated by nano-TiO
2
sol.
These results provided some scientific and technical references for application
of nano materials. However, nano-TiO
2
under sunlight will generate oxygen
radical, but the lipid of cell membrane could be overoxidized when the
quantity of oxygen radical surpassed the tolerance of the anti-oxidation system
of plant.
4.
R
EMEDIATION OF
P
OLLUTED
S
OIL AND
W
ATER
Degree of soil and water pollution in agro-ecosystems has been increased
in the past decades, which depressed the sustainable development of
agriculture, aggravated the threat to food security. Many attempts of
remediation of polluted soil and water with photocatalytic reaction of nano-
TiO
2
were increasingly studied. Some investigations revealed that nano-TiO
2
could degrade many kinds of pesticides to large extent except triazines, such
as atrazine atranex and simazine [17]. Nano-TiO
2
was used for treatment of
volatile chlorinated organic compounds (VOCs) polluted soils, e.g.
trichloroethylene and tetrachloroethylene. Photocatalytic sheets made from
corrugated paper containing nano-TiO
2
powder absorbed by activated carbon
powder to purify the polluted soil on the ground using sunlight were designed.
The photocatalytic sheets cover the polluted soil. After heating, the VOCs in
soil violated and captured by activated carbon, while nano-TiO
2
decomposed
them [18].
5.
R
ESEARCH
P
ROSPECTS
Based on the photo-induced decomposition reaction and photo-induced
hydrophilicity of nano-TiO
2
, more practical uses in sustainable agriculture
would be exploited with the deep studies in future. Combined effects of nano-
TiO
2
and ultraviolet light on microbial inhabitation need further investigation.
