低磷胁迫对水稻铁、锰吸收和积累的影响

Effect of Low Phosphorus Stress on Fe and Mn Absorption and Accumulation by Rice Shoots

在盆栽土培条件下,采用不同耐低磷基因型508、580、99011、99112和低磷敏感基因型99012、99056为材料,研究了不同生育时期低磷胁迫对水稻铁、锰吸收和积累的影响.结果表明,不同磷效率水稻基因型间茎叶相对铁、锰含量差异并不明显.分蘖期时,低磷胁迫条件下,低磷敏感基因型水稻茎叶铁含量显著下降,耐低磷基因型受到的影响明显小于低磷敏感基因型.孕穗期时,只有99056茎叶铁含量在低磷胁迫时显著降低;而茎叶锰含量除99112外其它基因型均显著降低.至成熟期,由于受转移效率的影响,水稻茎叶铁、锰含量变化明显比前期复杂.低磷胁迫条件下,耐低磷基因型水稻籽粒铁、锰含量呈下降趋势,低磷敏感基因型籽粒铁、锰含量呈上升趋势.低磷胁迫降低了铁、锰在水稻地上部的积累量.在生育前期,耐低磷基因的铁、锰积累量显著高于低磷敏感基因型;生育后期,耐低磷基因型的绝对积累量优势消失,但相对积累量优势变大.

In order to investigate the effect of low-P stress on iron and manganese absorption and accumulation by rice genotypes at tillering, booting and maturity stages, pot experiments were conducted using low-P tolerance rice genotypes 508, 580, 99011, 99112 and low-P sensitive rice genotypes 99012 and 99056. The result showed that the difference relative Fe and Mn contents in stems and leaves between the low-P tolerance rice genotypes and low-P sensitive rice genotypes was not obvious. The low-P stress decreased the Fe contents in stems and leaves at the tillering stage of the low-P sensitive rice genotypes larger than those of the low-P tolerance rice genotypes. At the booting stage, the Fe content of only 99056 significantly decreased, while the Mn content significantly decreased except 99112 under the low-P stress. At the maturity stage, the variations in Fe and Mn contents in rice stems and leaves were seen more complicated than those at early growth stages. The Fe and Mn contents in seeds of the low-P tolerance rice genotypes signifi cantly decreased, but those of the low-P sensitive rice genotypes increased. The low-P stress largely decreased the Fe and Mn accumulations in all the rice genotypes, and the accumulations of Fe and Mn were much higher in the P-tolerance rice genotypes than in the P-sensitive rice genotypes at the early growth stages. The difference in accumulations of Fe and Mn in the two rice genotypes declined, but the relative accumulations of Fe and Mn in the P-tolerance rice genotypes increased at the late growth stage. Fig 4, Tab 4, Ref 25