硅对镉胁迫下水稻幼苗不同叶位叶片类胡萝卜素含量的影响

Effect of Silicon under Cadmium Stress on Carotenoids Contents of Seedlings in Oryza sativa L. at Different Leaves Position

通过水培试验，研究不同硅浓度（0、30、80、130、180mg·L^-1 SiO2）对锅（4．0mg·L^-1 Cd^2＋）胁迫下水稻幼苗不同叶位叶片胡萝卜素、叶黄素、总类胡萝卜素含量的影响。结果表明：适当浓度硅（30—80mg·L^-1 SiO2）可提高锅胁迫下水稻幼苗倒5叶位叶片类胡萝卜素含量，且80mg·L^-1 SiO2达到最佳效果，但过高浓度（130—180mg·L^-1 SiO2）对水稻幼苗倒5叶位叶片类胡萝卜素含量有一定的抑制作用；倒4叶位的3种色素含量均随着SiO2浓度的增加而呈上升趋势，当SiO2浓度为180mg·L^-1时，3种色素含量达到最高（0．3820、0．2372、0．6192mg·g^-1 FW），分别为单独锅胁迫下的99．61、112．31、104．29％；倒3叶位叶片的胡萝卜素、叶黄素、总类胡萝卜素含量随着SiO2的增加呈现先降后升的趋势，当SiO2浓度为180mg·L^-1时，三者均达到最大值，分别为0．4772、0．3060、0．8832mg·g^-1FW；而硅对镉胁迫下水稻幼苗倒2、倒1叶位的3种色素含量的变化趋势影响很小。

Effects of silicon under cadmium stress on caretene,lutein and carotenoids content of Oryza saliva L. seedlings in different leaves position were studied by hydroponics culture method. Oryza sat/va L. seedlings were treated with the concentration of 4.0mg·L^-1I Cd^2 ＋ and 0, 30,80,130,180 mg·L^-1 SiO2. The results showed that appropriate concentration of silicon （30 -80 mg·L^-1 SiO2 ） under Cd stress could improve the carotenoids content in the fifth leaf from the top of Oryza sativa L. seedlings, and 80 mg·L^-1 SiO2 achieved the best results, but the high concentration （ 130 - 180 mg·L^-1 SiO2 ） restrained the carotenoids content of the Fifth leaf from the top of Oryza sativa L seedlings. Three pigments content of the fifth leaf from the top showed an increasing trend with the increase of SiO2 concentration. With the SiO2 concentration of 180 mg·L^-1, the three pigments content reached the highest （0. 3820,0. 2372,0. 6192 mg·L^-1. FW）, which were 99.61%, 112.31% and 104.29% under sole cadmium stress. With increasing SiO2 , the carotene ,hitein and caretenoids content in the fifth leaf from the top of Oryza sativa L. seedlings went down then up. When SiO： concentration was 180 mg·L^-1, all reached the maximum （0.4772,0.3060,0. 8832 mg·L^-1. FW）, but the effects of silicon under cadmium stress on the three pigment content in the 2th and the 3th leaf from the top of Oryza sativa L. seedlings were very small.