中文摘要：

采用培养试验方法研究了硅肥对酸性土壤中锰毒性的影响,旨在为酸性土壤锰毒害的防控提供科学依据.结果表明,甘蔗的根际效应明显,根际土壤中的pH值、有效硅含量较低而活性锰及水溶态锰、交换态锰、有机结合态锰、碳酸盐结合态锰、铁锰氧化态锰含量均显著高于土体.然而,施用硅肥（偏硅酸钠）后,土壤活性锰含量和水溶态、交换态、有机结合态锰含量均显著降低,但是硅肥对根际土壤锰含量和形态的效应弱于土体;并且,施用硅肥使甘蔗地上部锰含量（47.1～112.1 mg/kg）显著降低,并且有随着硅肥用量（0.5～2.1 g/kg）增加而降低的趋势;虽然硅肥的施用也减少甘蔗地上部铁的含量,但铁锰比值却从对照的2.51增加至2.92～5.72之间.因此,施用硅肥后甘蔗株高、总生物量分别提高4.07％～15.24％、8.41％～28.03％.可见,硅肥的施用减轻了酸性土壤中锰的毒害.

英文摘要：

Effect of Si fertilizer on Mn toxicity in acid soil was investigated by pot culture, in order to provide scientific basis for preventing Mn toxicity in acid soil. The results showed that there was significant rhizosphere effect in sugarcane including lower pH, available Si content and higher contents of active Mn, water soluble Mn, exchangeable Mn, organic chelated Mn, carbonate combined Mn, ferrimanganic oxidation state Mn in rhizosphere soil than those in non- rhizosphere soil. Further, the contents of active Mn, water soluble Mn, exchangeable Mn, organic chelated Mn reduced significantly under applying Si fertilizer （sodium metasilicate）, but effects of Si fertilizer on Mn content and form in rhizosphere soil was lower than those in non-rhizosphere soil. Shoot Mn content （47.1-112.1 mg/kg） decreased significantly under applying Si fertilizer compared with no Si fertilizer application in sugarcane, and which decreased further with Si fertilizer application increasing from 0.5 to 2.1 g/kg. Although, shoot Fe content in sugarcane reduced along with Mn content reducing under applying Si fertilizer, the ratios of Fe to Mn increased from 2.92 to 5.72 in the treatments of applying Si fertilizer, which were significantly higher than that of control （2.51）. Sugarcane plant height and total biomass under different Si fertilizer treatments increased by 4.07%-15.24% and 8.41%-28.03%. In a word, Si fertilizer can alleviate Mn toxicity in acid soil.