硅对高硼高盐胁迫下小麦生长及离子吸收的影响

Effects of Silicon on Growth and Ion Uptake of Wheat Under Combined Stresses of Excessive Boron and High Salinity

选取小麦(Triticum aestivum Linn.)为供试植物,利用盆栽试验研究了不同添加量的硅(0、50、100 mg·kg-1)对高硼(300 mg·kg-1)高盐(5 g·kg-1氯化钠)胁迫下植物生长以及对主要无机离子吸收的影响。结果表明,在硼盐联合胁迫下,硅能够提高小麦生物量,抑制对硼和钠的吸收,促进钾的吸收,降低植株钠钾比(Na/K),对钙、镁离子的吸收则没有显著影响。100 mg·kg-1硅处理对硼盐联合胁迫的缓解效果大于50 mg·kg-1硅处理。研究认为,硅能够通过抑制小麦对硼和钠的吸收,促进钾的吸收,缓解硼和盐联合胁迫对小麦生长的抑制作用。

Silicon（Si）has showed to improve the tolerance of plants to abiotic stresses. However, it is still unclear whether Si can enhance plant tolerance to combined stresses of excessive B and high salinity. A pot experiment was conducted with wheat（Triticum aestivum Linn.）grown in combined B（300 mg·kg^-1）, salinity（5 g·kg^-1 NaCl）, and Si（0 mg·kg^-1, 50 mg·kg^-1, and 100 mg·kg^-1）to investigate the growth and ion uptake of wheat. Silicon increased wheat biomass and potassium（K）uptake, but inhibited the uptake of B and sodium（Na）, thus reducing the tissue Na/K ratios. Silicon showed no significant effects on calcium（Ca）and magnesium（Mg）uptake. A greater alleviating effect of Si on combined stresses of B and salinity was observed under 100 mg Si·kg^-1than under 50 mg Si·kg^-1. These results suggest that Si is able to alleviate the inhibition of wheat growth by combined stress of B and salinity via reducing B and Na accumulation and promoting K uptake.