磷水平对不同耐低磷水稻苗根系生长及氮、磷、钾吸收的影响

Effect of Phosphorus Level on Root Growth and N, P & K Uptake of Rice with Different P Efficiencies at Seedling Stage

选取3个耐低磷水稻基因型99011、580和99112及1个磷敏感基因型99056为材料，采用营养液培养，比较了它们在不同磷水平下苗期根系的生长状况及对氮、磷、钾的吸收情况，结果表明，耐低磷基因型适应低磷的能力较强，它们具有较长的根系、较大的根体积和根干重，其中99011和580表现尤为突出，且它们的根系受磷水平变化的影响明显小于敏感基因型99056；0．081～0．161mmol／L的磷处理更有利于耐低磷基因型根系的发育，并且促进氮和钾的吸收，此时，植株能够吸收较正常磷处理更多的氮和钾；而磷敏感基因型99056吸收氮和钾的量随供磷水平的下降而减少，并且吸收磷的总量受磷水平变化的影响显著较3个耐低磷基因型大。

Three low-P tolerant rice genotypes named 99011, 580 and 99112, and one low-P sensitive rice genotype named 99056 were used in this experiment to investigate the effects of supplied phosphorus level on their root growth and N, P, K uptake at seedling stage. The results showed that low-P tolerant rice genotypes, especially 9901 land 580, had longer and bigger roots, and larger dry root weight than low-P sensitive rice genotype ; and the root characters of 99011,580 and 99112 were less affected by the changed phosphorus level than those of 99056. Their roots grew better at P level ranging from 0. 081 mmoL/L to 0, 161 mmoL/L than they did at other P levels, and in this P concentration range they could uptake more N and K than they did in sufficient P treatment of 0. 323 mmooL/L, so as to promote their nutritive organs grow well at seedling stage. However, low-P sensitive riee genotype 99056 absorbed less N and K with decreasing of P level, and its total P accumulation was more affected by the changed P level than 99011, 580 and 99112.