Abstract:

Using the arid awning since 2004, we simulated the effect of different rainfall years on the wheat yield and soil moisture, and took the normal-water year as the research object. The results showed that, during the growth period of wheat in the 11 research years, the rainfall was higher than the perennial rainfall (231.8mm) for 2 years, accounting for 18%, and was similar to the perennial rainfall level for 3 years, accounting for 27%, in other years, the rainfall was lower than the perennial rainfall level; and the rainfall was extremely uneven in the growth period, the drought period was also different, and the great climate had more significant impact on wheat growth. During the 11 years, the yield of wheat showed a downward trend, and the average annual reduction was 673.5 kg/hm² per year from 2004 to 2008, and the average yield decreased by 628 kg/hm² per year from 2009 to 2014. The number of ears of wheat decreased, while 1000 kernels weight increased, and the grain number per spike was relatively stable. Soil moisture showed a downward trend during the sowing period, and soil moisture was relatively stable during harvest period. The yield had an extremely significant and positive correlation with the number of ears and the soil water content during the sowing period, and a significantly positive correlation with the grain number per spike.

Key words: coupling of water and fertilizer, yield, soil moisture, wheat, long-term positioning