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

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.