| This experiment was carried out under a full-automatic rain shelter in 2008-2009 year at the Henan Agricultural University Science and Technology Education Garden area, by means of the analysis on soil moisture dynamic change and investigation of growth, physiology and ecology effect, yield effect of winter wheat ,studied the effect of Physiology and Ecology of Water Deficit in Late Growth Stages under Different Fertility , the main conclusion as follows:(1) The soil moisture raised with increase of the irrigation amount and soil fertility improvement, high fertility of soil moisture contents significantly higher than in low fertility of soil. Dry conditions, application could improve the soil water potential, thereby improving the effectiveness of the soil moisture and keep some for plant growth signifying "null" becoming "effective" water, thereby raising the soil moisture.(2) The dry matter accumulation of winter wheat increased with the increase of soil fertility and soil moisture. The dry matter accumulation increased with the increase of soil fertility under full irrigation in all stages, and the difference did not reach the significant level between the treatments. But the increase of soil fertility had a obvious regulation effect to the increase of the dry matter accumulation under drought condition.(3) The photosynthetic rate of winter wheat flag leaves had decrease in large amplitude with greater stress intensity, a long time to intimidate and lower soil fertility. The different treatments did not reach the significant level. It showed that higher soil fertility could mitigate negative effects of drought to winter wheat flag leaves photosynthetic rate.(4) The SOD activity of winter wheat flag leaves increased with the soil fertility and moisture increases. The SOD activity increased a little under mild drought. The decrease amplitude of the SOD activity largened as soil fertility raising on the condition of moderate drought and heavy drought. The content of MDA and solubility sugar in the strength and coercion to stress in the time but gradually increased, and increase the rate of increase in the soil fertility. Among them, the different fertility treatments did not have the significant difference between SOD activity, the content of MDA and solubility sugar under full irrigation in all stages, which showed that the soil moisture performanced a major role to them.(5) The 1000-kernel weight of winter wheat, the spike number, grain number per spike and the yield were increase with the improving of the soil fertility and water content, and compared with the full irrigation in all stages, sufficient irrigation with each drought stress of 1000-kernel weight, spike number, grain number per spike and the yield, number of output declines linearly with the increase of soil fertility, which is the leading factor of soil water content. Among them, drought in heading stage had greater effect to spike number, grain number per spike, drought in filling stage had greater effect to 1000-kernel weight.(6) Water use efficiency of low water-stressed wheat was highest under high and moderate fertility conditions, and under low fertility conditions WUE was highest in high water stressed. WUE of mild drought and moderate drought in filling stage was higher in high fertility; and it was higher in heading stage under moderate fertility, whith showed that higher soil fertility could relieve the injury of drought to winter wheat growth sighificantly.In summary,the detrimental effect of drought stess to winter wheat was relieved with the soil fertility improving. Probably because with the soil fertility improving, winter wheat roots vigorous growth, the effective water content of soil increased, the photosynthetic rate and water conditions improved,which made winter wheat keep larger photosynthetic area and longer action time. In arid and semi-arid areas, improving soil fertility can be used to alleviate the adverse effects of drought on the yield of winter wheat. |
