硫化氢促进缺磷条件下水稻根系细胞壁磷的再利用

摘要

Exogenous addition of 10 nmol/L H2S donor NaHS significantly increased available P content in rice under P starvation condition. Further study demonstrated that H2S positively stimulated the increase of pectin content, accompanied with the enhancement of pectin methylesterase (PME) activity, then increased the cell wall P release, finally helped rice to survive underno P condition. What's more, the addition of H2S scavenger hypotaurine (HP) further emphasized the important roles of H2S in rice root cell wall P release. In addition, H2S stimulated the expressions of phosphate transporter genes OsPT6 and OsPT8 which are involved in the transport of soluble P from root to shoot.%在缺磷条件下,外源添加10 nmol/L H2S供体NaHS可以显著提高水稻体内的有效磷含量.进一步研究发现,H2S主要通过提高水稻根系细胞壁中的果胶含量和果胶甲酯酶的活性来增加水稻细胞壁磷的释放,从而确保水稻在缺磷条件下的存活.添加H2S的清除剂亚牛磺酸后进一步验证了H2S对水稻根系细胞壁磷再利用的调控作用.同时,测定3个负责水稻体内磷转运的磷转运子基因的表达,结果显示H2S主要通过上调磷转运子OsPT6和OsPT8基因的表达来提高水稻体内磷从根部往地上部的转运.