Effects of soil-moisture monitoring supplemental irrigation on water consumption characteristics and nitrogen accumulation and translocation in different wheat cultivars

Aimed to optimize the effects of supplemental irrigation at different growth stages on water consumption characteristics and nitrogen distribution and translocation in wheat, a field experiment was conducted to study effects of soil-moisture monitoring supplemental irrigation on water consumption characteristics and nitrogen accumulation and translocation with the cultivars of Jimai22 (J22) and Weimai8 (WM8). Three irrigation treatments were designed: W0 with no irrigation during the whole growth stage, W1 with the relative water contents at jointing and anthesis stages being 70% and W2 with the relative water contents at 8 d after jointing and 8 d after anthesis stages being 70%. The results showed that grain nitrogen accumulation at maturity, nitrogen translocation rate and efficiency from vegetative organs to grain after anthesis under W1 and W2 were significantly higher than those under W0 in both cultivars. Comparing to W1, W2 of J22 had higher proportion of grain nitrogen accumulation at maturity, the nitrogen translocation rate and efficiency. However, WM8 showed the reversed change under the treatments W1 and W2. The water consumption amount from anthesis to maturity of treatment W2 was the highest in both cultivars. The total water consumption of J22 under all irrigation treatments was significantly lower than that of WM8. The ratio of precipitation to total water consumption in J22 was significantly higher than that in WM8. Under treatment W2, the ratio of irrigation and precipitation to total water consumption amount were both higher than those of WM8. Treatment W2 of J22 had higher grain yield, water use efficiency, nitrogen fertilizer productive efficiency, nitrogen uptake efficiency, and nitrogen harvest index in irrigation scheduling under the experimental condition, whereas the most appropriate irrigation regime recommended for WM8 is treatment W1. Compare to WM8, J22 had higher grain yield and water saving efficiency.