Agriculture Reference
In-Depth Information
Short Communication B
E
FFECT OF
A
L
,
C
D AND
C
U
I
NTERACTIONS ON
P
HOTOSYNTHETIC
C
HARACTERISTICS AND
S
UGAR
C
ONTENTS IN
B
ARLEY
L
EAVES
D
IFFERING IN
A
L
T
OLERANCE
Guo Tian Rong
1
, Mi Zhong Xiang,
Zhang Yan Hua and Tian Run Gang
Life Science College, Shaoxing University, Shaoxing, 312000,
People's Republic of China
A
BSTRACT
The decline in crop production is commonly observed on acid soil, further, a
multiple heavy metal pollution except for Al on acid soil is detected in many areas. The
present experiment was conducted by using two barley genotypes differing in Al-
tolerance, Al tolerant
cv.
Gebeina and Al sensitive
cv.
Shang 70-119, to determine the
effect of Al, Cd, Cu individual, binary and ternary combinations on the photosynthetic
characteristics and the contents of sucrose and starch in leaves of barley seedlings. The
results showed that there were significant decreases in leaf area, leaf fresh and dry
weight, chlorophyll content, net photosynthesis (Pn), stomatal conductance (gs),
Fv/Fm
ratio evaluated for chlorophyll fluorescence and sucrose contents, but obvious increases
in internal CO
2
concentration (Ci) and starch contents in barley leaves when exposed to
the stress medium. These decreases or increases were more marked in Shang 70-119 than
in Gebeina. In addition, binary metals combinations of Al + Cd and Al + Cu both resulted
in severe changes in these values for two genotypes when compared with the Al alone
treatment, indicating the existence of notable synergistic interactions between Al and Cu
or Al and Cd, in particular for Shang 70-119. However, ternary metals combination of Al
+ Cu + Cd produced different interactions in two kinds of genotypes, thus, the slighter
toxicity caused by ternary metals mixture than that caused by binary metals mixture was
observed in Gebeina, while the reverse results showed in Shang 70-119, suggesting the
notable synergistic effect of the three metals existed in sensitive genotype but not in
