Physiological Responses Of The Three Ornamental Bamboos And Regulations Of Silicon And Rare Earth Element To Mercury Stress

Sasa fortunei (Van Houtte) Fiori, Sasa argenteastriatus E.G.Camus,Pleioblastus kongosanensis f. aureo-striatus were treated with different massconcentration of Hg and certain mass concentration of silicon and La from June 2006to October 2006, physiological responses of the three the reaction of the threebamboo species to Hg stress and the regulation effect of silicon and rare earthelement were researched in this paper, and the aim of this paper is to furnish theorybasis and practice thereunder about bamboo species developing widely in heavymetal polluted areas. The result indicates,Under the stress of low mass concentration of Hg, membrane permeability,photosynthetic rate, the content of MDA, soluble carbohydrate, soluble protein,proline, polyamine, activities of SOD, POD were steady relatively, the activity ofCAT was restrained and root vigor was restricted in different degrees. Under thestress of high mass concentration of Hg, the content of polyamine increased and theactivity of POD enhanced at premier days, at the following days, photosyntheticrate,the content of soluble carbohydrate, proline, the activity of CAT decreased ofthe three bamboo species, the content of chlorophyll,soluble protein descended andmembrane permeability, the content of MDA increased in fortunei andargenteastriatus, the content of soluble carbohydrate decreased in fortunei andkongosanensis, the activity of SOD descended of fortunei,but no change ofkongosanensis's membrane permeability and protein content. The modality offortunei changed the most, then the argenteastriatus, kongosanensis had no changesthen the experiment finished. The root vigor offortunei and argenteastriatus wereweaker than kongosanensis. So it can be concluded that, the withstand ability to Hgstress is. Pleioblastus kongosanensis＞Sasa argenteastriatus＞Sasa fortunei.Silicon had no appearent effect to low mass concentration of Hg stress, silicontreatment under high mass concentration of Hg increased the content of polyamineand stabilize the activity of POD at primier days, enhanced photosynthetic rate andCAT activity, depressed the ascending of embrane permeability, the increasing ofthe content of MDA and proline, prevented the decreasing of soluble protein andcarbohydrate, chlorophyll content in fortunei, argenteastriatus, augmented SODactivity in fortunei, silicon enhanced root vigor distinctly under any mass concentration of Hg. It is conclude that 300mg/kg silicon could slacken thephysiological injure of the three bamboo species in different degree under Hg stress,and it has the best effect to fortunei.5Omg/L rare earth element has similar functionto silicon under Hg stress, it has certain effect to some indexes of argenteastriatusand kongosanensis under Hg stress, but the effect of silicon is better than rare earthelement.