Nutrient distribution, growth, and water use efficiency in maize following winter wheat irrigated by sprinklers or surface irrigation.

摘要

The pattern of distribution of nutrients in maize varied with the method of irrigation used for winter wheat. The major nutrient uptake zone was concentrated closer to the soil surface in fields irrigated with sprinklers than in surface-irrigated fields, especially in dry years, which lowered the amounts of available soil N and P. Maximum values for plant height, leaf area index, and grain yield were significantly higher (P<0.05) in surface-irrigated fields when water was supplied in large quantity. When supplied in small quantity, the difference between the irrigation methods was reduced because of the wet and rainy weather during the growing season of winter wheat. The amount of water held in the soil profile was greater, and deep percolation minimal, in sprinkler-irrigated fields, which could lower the amount of soil N lost from leaching. Water use efficiency (WUE) was higher in surface-irrigated fields. These observations suggest that to maximize grain yield of winter wheat and maize, fertilizer application to maize in sprinkler-irrigated fields should change correspondingly. The management of the succeeding crop should thus reflect the irrigation method used for the preceding crop in order to obtain the highest yield.