低铁胁迫对不同耐低磷玉米生长及磷、铁养分吸收的影响

Effects of Fe-Deficiency on Plant Growth and Uptake of P and Fe in Different P-Genotype Maize

用营养液培养方法研究了耐低磷和低磷敏感玉米幼苗对低铁胁迫的基因型差异。结果表明,铁处理和基因型对玉米的生长和养分吸收影响显著,铁处理和基因型之间存在互作。低铁胁迫对各基因型玉米幼苗地上部生物重的影响十分明显,对低磷敏感基因型玉米地上部生物重的抑制作用显著大于耐低磷基因型。铁在玉米植株中集中分布在根部,与耐低磷特性无关。低铁胁迫显著降低了各基因型玉米幼苗叶片的叶绿素含量,但基因型间无明显差异。低铁胁迫对根系生长有一定的促进作用,可以诱导地上部同化产物向根系转运,促进根系代偿性伸长。

The genotypic differences in response to Fe deficiency of maize with different tolerance to low-P stress were investigated in nutrient solution under controlled conditions. The results indicated that genotype and Fe treat- ment had a remarkable effect on maize growth and nutrient absorption, There was an interactive relation between genotype and Fe treatment. Fe deficiency had a significant effect on seedling growth. The genotypic differences exis- ted in response to Fe deficiency, which decreased the dry weight of shoot in low-P sensitive genotypes more signifi- cantly than in low-P tolerant genotypes, and root/shoot ratio of low-P tolerant genotypes significantly increased. The phosphorus distribution was not related to the ability to tolerant phosphorus deficiency, commonly distributed in the root. The same response to Fe deficiency existed in chlorophyll content between P sensitive genotypes and P tolerant genotypes, the contents of different genotypes in chlorophyll decreased greatly respectively. The Fe-deficiency could increase root growth, and increased transport of assimilate products from the above ground parts to roots.