Survey on Qualitative and Quantitative Traits of Winter Wheat under Different Irrigation Treatments Using Weighing Lysimeter in North China Plain

As the world’s population increases, water resources for agriculture become more restrictive and efficient water use takes on greater importance. In 2012-2013 experiment, Irrigation treatments were (I1): Irrigation before sowing (60 Liter), (I2): Irrigation before sowing (30 Liter) + before freezing (30 Liter); (I3): Irrigation before sowing (30 Liter) + before freezing (30 Liter) + Irrigation in the beginning of erecting stage (60 Liter) + Irrigation at flowering stage (60 Liter); (I4): Irrigation before sowing (30 Liter) + Irrigation before freezing (30 Liter) + Irrigation at the booting stage (60 Liter) + Irrigation at flowering stage (60 Liter). The weighing lysimeter system is located in National Precision Agriculture Demonstration Station in Xiaotangshang Town of Beijing. The maximum and the minimum LAI was achieved in I3 (5.96), and I1 (5.25), which had meaningful difference with each other. The highest grain yield, harvest index, potassium percentage and ash percentage of forage wheat at flowering stage was obtained by I4. The maximum total biological yield, forage protein percentage, seed phosphorus percentage and seed potassium percentage was related to I3, but it had no significant differences with I4. The higher a thousand seed weight was obtained by I4 (34.85 g), followed by I3 (31.93 g), I2 (30.33 g), and I1 (28.76 g). The results from the study indicate that irrigation of winter wheat throughout the booting stage and flowering stage increased grain yield, harvest index, potassium percentage, ash percentage of forage wheat at flowering stage, seed and forage protein percentage. In 2013-2014 experiment, Irrigation treatments were (I1) no irrigation, (I2) irrigation only at jointing stage(60L), (I3) irrigation at jointing(60L) and flowering stage(60L), (I4) irrigation at jointing stage (April 8th,60L), 100% flowering stage (April 30th,60L), and grain filling period (May 10th,60L). The highest spike number per lysimeter was related to full irrigation (I4), but it had no significant differences with other treatments (P>0.05). I4 had obtained the highest grain yield which was 7.55 ton/ha. Grain yield in I1 and I2 was 4.49 ton/ha and 4.65 ton/ha, respectively. The maximum and the minimum harvest index was related to I4 (44.79%) and I2 (37.97%), which had significant differences with each other. Therefore, on the basis of results of these two experiments, it is important to irrigate winter wheat throughout the booting stage and flowering stage in order to achieve higher yield.