Preliminary Study on Effects of Roots-Divided Alternate Irrigation on Nutrient Uptake by Maize

Effects of roots divided alternate irrigation on nutrient uptake were studied with controlled alternate irrigation (CAI) for half part of root zone, controlled fixed irrigation (CFI) for half part of root zone and conventional irrigation (CI) for whole root zone. The results showed total N uptake of CAI was higher than that of CFI, but there is no difference compared with CI at early jointing stage. But at the end of maize development, the total N uptake of CAI treatment was higher than that of CFI and CI. And total P uptake in CAI treatment was higher than that of the other two irrigation methods. Compared with CI treatment, plant N and P use efficiency in CAI treatment was enhanced by 25.1% and 25.3%, respectively. In CAI treatment, irrigation water was saved by 10.3% compared with CI, water use efficiency was the highest among the three irrigation treatments, and increased by 20.1% compared with CI.