Effect of Partial Root-zone Irrigation at Different Growth Stages on Dry Mass Accumulation and Water and Nitrogen Use of Maize

Under four NK levels,the effect of partial root-zone irrigation during the different growth stages on dry mass accumulation,water and N use of maize were studied using a pot experiment.The results showed that compared to conventional irrigation,the partial root-zone irrigation during different growth stages lowered water consumption significantly,and alternate partial root-zone irrigation at the seedling to jointing stage lowered or increased dry mass accumulation slightly,and increased water use efficiency by 22.8% and had the highest N apparent recovery fraction at medium NK level(0.12 g N per kg soil and 0.12 g K2O per kg soil).Under the same irrigation,medium NK level had higher dry mass accumulation,water use efficiency and N uptake of maize.Therefore,alternate partial root-zone irrigation at the seedling to jointing stage of maize is an efficient irrigation method under moderate NK level.