不同水稻品种对难溶性磷利用能力的初步研究

采用子母盆栽水平分根试验,研究了水稻耐低磷品种莲塘早3号和低磷敏感品种新三百粒对Fe-P、Al-P、Ca-P3种难溶性磷的利用能力。结果表明,与母盆营养液中含正常磷的处理相比,子盆和母盆均不含磷的处理两品种的生物量、根系氧化力下降、MDA含量上升,以难溶性磷为唯一磷源加入子盆石英砂的处理其变化幅度更小,磷含量也比完全缺磷的明显要高,说明根系对难溶性磷的主动活化在起作用;耐低磷品种较高的生物量、磷含量和根系氧化力以及较低的MDA含量表明其活化利用难溶性磷的能力比低磷敏感品种强;不同难溶性磷处理间,各指标的差异与不同形态难溶性磷对水稻有效性的差异有关。另外,缺磷或低磷条件下根冠比增加;磷的有效性越低,其根冠比越高。

Preliminary study on the utilization ability of insoluble phosphate in various rice culitvars

A horizontal division of root system was used to study the utilization ability of insoluble phosphate in low-phosphorus-tolerant cultivars(Ltz3) and l ow-phosphorus-sensitive cultivars(Xsbl). The results were as follows: Compare d to treatment with normal level phosphorus of solution in the lower pot, the dry matter weight, root oxidation decreased, MDA content increased in the treatment without phosphorus in whole system, but in the treatment with insoluble phosphat e in quartz in upper pot, the indexes changed more slightly and had higher phosp horus content, which suggested the active mobilization of phosphate of root had functioned; Low-phosphorus-tolerant cultivar had higher dry matter weight, roo t oxidation, phosphorus content and lower MDA content than low-phosphorus-sensit iv e cultivar, indicating its utilization ability of insoluble phosphate was strong er. The differences of each index among treatments with different insoluble phos phate might be related to the different availability of different insoluble phos phate on rice. The ratio of root to shoot increased under low phosphorus or phos phorus deficiency condition, and the lower phosphate availability, the ratio of root to shoot was higher.