土壤水分胁迫对小麦养分分配及产量的影响

EFFECT OF SOIL WATER STRESS ON NUTRIENT DISTRIBUTION AND YIELD OF WHEAT

在温室盆栽条件下研究了土壤水分胁迫对小麦养分分配及产量的影响。结果表明，随土壤水分胁迫加重，植株将吸收的氮、磷营养较多地分配于根中，在地上部中的比率少，最终分配至穗部的比率降低，磷素分配至根系高峰出现提早;水分胁迫越重，成熟期钾素分配至根系的比例越高，而最终分配至穗部的越低，从而导致氮、磷、钾肥利用效率和产量降低。由于轻度水分胁迫与对照在氮、磷、钾最终分配至穗部比率及产量上无显著差异，因而可以认为相对含水量60％为养分正常分配及获得高产的下限指标，可作为制定节水栽培措施的参考。

The effect of soil water stress on nutrient distribution and yield of wheat was studied in pot culture. The results showed that with increase of water stress, the nitrogen and phosphorus absorbed by plant distributed to root more than to shoot. The distribution rate of nitrogeri in spike was 49. 61% (high water stress), 61. 73% (middle stress), 61. 78% (Light stress), 59. 08% (control), and phosphorus was 51. 21%' 72. 3%、77. 14% and 79. 16%, respectively. The peak of phosphorus content appeared in root was at heading stage under high and middle water stress conditions and at anthesis stage with light water stress and control treatments. With water stress increasing the potassium distributed to spike was decline and 1ed to the use efficiency of nutrients and yield decrease.Because of the distribution rate of N, P, K in spike and yield of wheat was not significant difference, so 60% of ralative water capacity could be a index for high yielding wheat and the accordance for making the measure of water-saving culture.