Yield and Water Use Efficiency Affected by Rainfall, Irrigation and Maize Varieties
Maize (Zea mays L. ) is one of the staple grain crops in the North China Plain (NCP). Though it grows in rainy season, the erratic summer rainfall makes irrigation very important to obtain higher production. 8-yr field results (1997~1999, 2001~2005) showed that maize yield was significantly affected by seasonal rainfall, its distribution and irrigation application. Irrigation at emergency was critical to ensure the seedling establishment. In dry seasons, four irrigation applications produced the maximum production. Grain yield was significantly correlated with rainfall in July and August (P<0. 01) under minimum irrigation condition, but not with total seasonal precipitation. Water use efficiency (WUE) was reduced with the increase in irrigation application, except in very dry seasons (less than 200 mm rain). The yield increase by the irrigation application from tasseling to anthesis was significant for most of the seasons. The optimized irrigation scheduling for maize was: in dry seasons, two more irrigations at stalk elongation and flowering beside the irrigation at emergency should be applied. In other seasons, more irrigation during earlier August, the tasseling to anthesis period, beside the irrigation for seedling establishment should be used. The yield variation also closely related with the cultivars. 3-yr field results showed that yield difference of the commonly local used cultivars exceeded 20% and WUE difference was about 12%~19%. Combining good cultivars with optimized irrigation scheduling is an effective measure to improve yield and WUE of maize in NCP.
grain yieldwater use efficiency (WUE)maizeirrigationcultivars
国家科技期刊平台
NSTL
万方数据
维普
