不同浓度的Si Ge对水稻幼苗生长的影响

Effect of Different Concentrations of Ge and Sion the Growth of Rice Seedlings in Solution Culture

利用人工控制光温条件的水培方法,研究了不同浓度的Si、Ge对水稻幼苗生长的影响。结果表明,对水稻幼苗进行Ge处理后,各处理之间的生物量均有所降低。在相同Ge浓度处理时,随着Si浓度的升高,生物量有增加的趋势。随着Ge处理浓度的增加,水稻地上部分含水量逐渐减少,对幼苗的毒害程度越来越严重,地上部Ge的浓度也呈逐渐增加的趋势。而随着Si的加入,毒害症状减轻,对于Ge2.5,Ge5.0,Ge10.0mg·L-1处理的植株而言,Ge含量均表现为降低的趋势。这说明Si对水稻植株吸收Ge有一定的拮抗作用。结果还表明,随着Si浓度的增加,水稻地上部含Si量明显上升,但Ge含量则呈降低趋势,即Si的加入减缓了水稻幼苗的Ge毒害。此外,通过对根系进行一定时间的浸泡,能有效除去吸附于根表及累积于根质外体中的Ge,从而为准确测定根细胞中的Ge提供了较为准确有效的方法。

Silicon is an analogue of germanium in chemical properties, so the r e may be an antagonism between silicon and germanium. A hydroponic experiment wa s conducted to investigate the effect of different Ge concentrations (2.5, 5.0, 10.0 mg·L-1) and Si (25, 50, 100 mg·L-1) on the growth of rice seedlings . The results showed that different concentrations of GeO2 in nutrient solution decreased biomass of rice significantly, while, different concentrations of sili con in solution enhanced the growth of rice seedlings. The biomass was highest a t the 50 mg·L-1 of Si concentration. The interaction between Si and Ge had l ittle effect on dry weights of rice seedlings. The increase of GeO2 concentratio n in nutrient solution could increase Ge concentrations in rice shoots but decre ase the water content of rice shoots, and had no effect on Si concentrations in shoots. Toxic symptoms on the leaves of rice exposed to nutrient solution with G e after 12 h were found and decreased with increasing Si concentrations in nutri ent solution, which indicated that Si could inhibit Ge uptake by rice roots. Mor eover, Si concentrations in shoots increased and Ge concentrations reduced with increasing Si concentration in solution, which suggested that there was an antag onism between Si and Ge at uptake and translocation by rice seedlings. In additi on, two extractable methods were used to determine Ge concentrations in rice roo ts.