|
Full Length
Research Paper
|
|
Effects of
nitrogen forms on
the growth,
ascorbate-glutathione
cycle
and lipid
peroxidation
in developing seeds
of vegetable soybean
Lei Chen1,2, Si-Chen Liu2,
Jun-Yi Gai1, Yue-Lin
Zhu1,2 *,
Li-Fei Yang2,
and Guo-Ping
Wei2
1National
Center for Soybean Improvement, Nanjing Agricultural
University, No. 1 Weigang, Nanjing, Jiangsu Province 210095,
China.
2College
of Horticulture, Nanjing Agricultural University, No. 1
Weigang, Nanjing, Jiangsu Province 210095, China.
*Corresponding author.
E-mail: ylzhu@njau.edu.cn. Tel:
+86-25-84396472.
Accepted 22 October, 2009 |
|
|
|
Abstract |
|
|
|
A pot culture experiment of nitrogen forms (NO3¯:NH4+)
with four ratios (100:0, 75:25, 50:50, and 25:75) in
nutrient solutions was conducted to examine the effects of
nitrogen forms on the growth, ascorbate-glutathione
(ASC-GSH) cycle
and lipid peroxidation
in developing seeds of vegetable soybean. Results showed that
the best plant growth vigor was observed in NO3¯
(75%), and then in NH4+ (50%). The
contents of ASC and dehydro-ascorbate (DHA), and
DHA/ASC ratio
in NO3¯ (75%) and NH4+
(50%) maintained stable values,
but obvious increases were observed
in NO3¯ (100%) and NH4+
(75%).
The GSH contents exhibited increasing trends, while the
increases in oxidized glutathione (GSSG) contents were only
observed in NO3¯ (100%) and NH4+
(75%), in which high GSSH/GSH ratios were observed. In NO3¯
(100%) and NH4+ (75%), the enzymes
activities in ASC-GSH cycle, including ascorbate peroxidase
(APX,
EC 1.11.1.11),
dehydro-ascorbate reductase (DHAR,
EC 1.8.5.1)
and glutathione reductase (GR, EC 1.6.4.2), expressed
increasing trends. Significant increases in lipid
peroxidation and
hydrogen peroxide
(H2O2) generation were also observed
in NO3¯ (100%) and NH4+
(75%) as against NO3¯ (75%) and NH4+
(50%). It was shown that the degree of
oxidative damage
was relatively low when the ratio of nitrogen forms was
75:25, and this could be a good guidance on the nitrogen
application in the cultivation of vegetable soybean.
Key words:
Nitrogen forms, seed development, ascorbate-glutathione
cycle, vegetable soybean. |
|
