酸性磷酸酶参与大豆子叶磷转运和利用

Involvement of Acid Phosphatase in Phosphorus Mobilization and Utilization in Cotyledons of Soybean (Glycine max L.)

本文以磷效率不同的两个大豆品种为材料,研究大豆幼苗期子叶酸性磷酸酶活性和同工酶谱对外源磷有效性的响应,及其参与子叶磷高效转运和利用的过程。结果表明:在幼苗生长前期,子叶酸性磷酸酶活性及其同工酶谱组成变化明显,而且不受外源磷有效性的调控;在幼苗生长的前8天,子叶全磷含量随着酸性磷酸酶的活性增加而显著降低,而且磷高效大豆品种比磷低效大豆品种具有较高的酸性磷酸酶活性和植株全磷含量。以上结果说明在大豆幼苗生长前期,由于大粒种子不仅具有较高的磷含量,而且具有较高子叶酸性磷酸酶活性,促进子叶有机磷的水解和转运是磷高效大豆品种适应低磷胁迫的生理机制之一。

Acid phosphatase （APase） activity and isoforms, as well as their involvement of phosphorus （P） remobilization were investigated in the cotyledons of two soybean cultivars contrasting in P efficiency at the early stage of plant growth at two P levels. Our results showed： APase activity and isoforms in cotyledons varied significantly at the early plant growth stage, which were independent of P availability in the growth medium; phosphorus content in cotyledons was decreased with the increase of APase activity during first 8 d of plant growth. Furthermore, the P-efficient cultivar exhibited higher APase activity and total P content in plants. All the results together suggests that enhanced P remobilization from bigger seeds to the other parts of seedlings resulted from higher APase activity in cotyledons might be one of physiological mechanisms of P-efficient plant adaotation to low P conditions.