磷肥施用量对无公害稻米磷化物含量及产量的影响

Effects of Applying Amount of Phosphoric Fertilizer on Rice Quality (Phosphide) and Yield of Non-pollution Rice

在土壤速效磷较丰富的中上等肥力田和速效磷丰富的上等肥力田进行磷肥施用量试验,结果表明:稻谷产量随P2O5施用量(0-6 kg/667m2)的增加而增加,均呈显著正相关(r中上=0.9954*,r上=0.9828*),其中,上等肥力田在施用0-6 kg/667m2增产幅度较小;P2O5施用达8 kg/667m2时产量不再提高.稻米中磷化物含量均呈现随P2O5施用量增加而增大趋势,当P2O5施量达8 kg/667m2时,稻米中磷化物含量中上等肥力田达临界值,上等肥力田超标;不施磷肥处理,稻米中磷化物均为3 mg/kg.稻米中磷化物含量直接与土壤速效磷含量和磷肥施用量相关.速效磷较丰富的中上等肥力田,种高产杂稻以667m2施P2O5 4-6 kg既安全又可获水稻高产;速效磷丰富的上等肥力田种优质稻,以667m2施P2O5 2-4 kg为宜.

The experiment was carried out on the middle-upper fertility field and upper fertility field with abundant active phosphorus to investigate effects of applying amount of phosphoric fertilizer on rice quality （phosphide） and yield of non-pollution rice. The results showed that the rice yield increased with increasing of amount of P2O5 applied （0-6 kg/667m^2）, which presented significant positive correlation （rmiddle-upper=0. 9954^＊ , rupper =0. 9828^＊ ） on two kinds of fields. The increasing rate of rice yield was small at the applying level was 0-6 kg/667m^2 of P2O5 in the upper fertility field and the yield did not increased after increasing P2O5 to 8 kg/667m^2. The phosphide content in rice grain increased with increasing of amount of P2 O5 applied. The phosphide content in rice planted in the middle-upper fertility field reached critical value and the phosphide content in rice planted in the upper fertility field got beyond the standard. The phosphide contents in rice planted on two kinds of fields are the same （3 mg/kg） without applying P2O5, The phosphide content in rice is directly related to active phosphorus content in field and applying amount of P2O5. 4-6 kg and 2-4 kg/667m^2 of P2O5 applied are suitable for higher yields of hybrid rice planted on the middle-upper and upper fertility fields respectively,