摘要
用在培养液中加低浓度NO_2^-,HSO_3^-,Mn^(2+)及向地上部喷洒氯霉素等四种方法促使小麦苗超氧物歧化酶(SOD)活性增加。SOD活性提高后,植株叶片对高浓度NO_2^-,HSO_3^-的抗性增强,表现在因NO_2^-,HSO_3^-害而产生的膜脂过氧化产物乙烷减少,叶绿素分解减轻。低浓度NO_2^-处理后的麦苗,不仅提高了对高浓度NO_2^-的抗性,同时对HSO_3^-的抗性也增强;同样,低浓度HSO_3^-处理也同时促进了麦苗对HSO_3^-和NO_2^-的抗性,即可交叉地提高。这些结果直接说明SOD和抗性有关。同时也为SO_2/HSO_3^-,NO_2/NO_2^-害的自由基学说提供了一个佐证。
Four treatments were used to increase SOD
activity of wheat plants. Wheat seedlings were
cultured first with Hoagland solution,then trans-
fered separately to the Hoagland solutions con-
taining (1) 18 mmol/L NO_2^-(NaNO_2), (2) 2
mmol/L HSO_3^-(NaHSO_3), (3) 4mmol/L Mn^(2+)
(MnCl_2). The fourth treatment was spraying
60mg/L chloromycetin solution on wheat leaves
4～6 times during the early growth period of
seedlings. The SOD activities of wheat leaves
of all four treatments were intensified(Table 1).
The resistance of wheat seedlings against high
concentration of NO_2^- and HSO_3^- was then
examined. The leaf segments were vaccum-
infiltrated with solutions of high concentration
of NO_2^- and HSO_3^- respectively, and then illu-
minated for 5～10 h. It was showed that the
production of ethane, one of the lipid peroxida-
tion products,and the destruction of chlorophyll
in leaf segments of induced plants was reduced
(Fig.1～4). Treatment with a solution of
low concentration of NO_2^- enchanced not only
the resistance of seedlings to high concentration
of NO_2^-, but also the resistance tO HSO_3^- .In
the same way, low concentration of HSO_3^- in-
duced higher resistance to both HSO_3^- and NO_2^-
It indicated that there was an interactive effect.
These results suggest that SOD plays an impor-
tant role in the resistance of plants against SO_2/
HSO_3^- and NO_2/NO_2^-. The higher the SOD
activity, the strongcr the resistance. It verifies:
the hypothesis that NO_2/NO_2^- and SO_2/HSO_3^-
injuries to plants are re1ated to free radical
formation.
关键词
小麦
超氧物歧化酶
HSO3^-
NO2^-
wheat
superoxide dismutase (SOD)
ethane production
chlorophyll destruction
NO_2^-
HSO_3^-
