Responses of water productivity to irrigation and N supply for hybrid maize seed production in an arid region of Northwest China

• Published in: Journal of arid land 2017-08, Vol.9 (4), p.504-514
• Main Authors: Ran, Hui, Kang, Shaozhong, Li, Fusheng, Du, Taisheng, Ding, Risheng, Li, Sien, Tong, Ling
• Format: Article
• Language: English
• Subjects: Agricultural management; Arid regions; Arid zones; Biomass; Corn; Crop production; Crop yield; Crops; Earth and Environmental Science; Evapotranspiration; Field capacity; Field tests; Geography; Irrigation; Irrigation water; Nitrogen; Physical Geography; Plant Ecology; Productivity; Seed production; Sustainable Development; Water; 反应; 地膜玉米; 杂交; 氮管理; 水分生产率; 灌溉量; 种子生产; 西北干旱地区
• ISSN: 1674-6767; 2194-7783
• DOI: 10.1007/s40333-017-0017-3

Water and nitrogen（N） are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Field experiments were conducted to study the responses of water productivity for crop yield（WP_（Y-ET）） and final biomass（WP_（B-ET）） of film-mulched hybrid maize seed production to different irrigation and N treatments in the Hexi Corridor, Northwest China during April to September in 2013 and also during April to September in 2014. Three irrigation levels（70%–65%, 60%–55%, and 50%–45% of the field capacity） combined with three N rates（500, 400, and 300 kg N/hm~2） were tested in 2013. The N treatments were adjusted to 500, 300, and 100 kg N/hm~2 in 2014. Results showed that the responses of WP_（Y-ET） and WP_（B-ET） to different irrigation amounts were different. WP_（Y-ET） was significantly reduced by lowering irrigation amounts while WP_（B-ET） stayed relatively insensitive to irrigation amounts. However, WP_（Y-ET） and WP_（B-ET） behaved consistently when subjected to different N treatments. There was a slight effect of reducing N input from 500 to 300 kg/hm~2 on the WP_（Y-ET） and WP_（B-ET）, however, when reducing N input to 100 kg/hm~2, the values of WP_（Y-ET） and WP_（B-ET） were significantly reduced. Water is the primary factor and N is the secondary factor in determining both yield（Y） and final biomass（B）. Partial factor productivity from applied N（PFP_N） was the maximum under the higher irrigation level and in lower N rate（100–300 kg N/hm~2） in both years（2013 and 2014）. Lowering the irrigation amount significantly reduced evapotranspiration（ET）, but ET did not vary with different N rates（100–500 kg N/hm~2）. Both Y and B had robust linear relationships with ET, but the correlation between B and ET（R~2=0.8588） was much better than that between Y and ET（R~2=0.6062）. When ET increased, WP_（Y-ET） linearly increased and WP_（B-ET） decreased. Taking the indices of Y, B, WP_（Y-ET）, WP_（B-ET） and PFP_N into account, a higher irrigation level（70%–65% of the field capacity） and a lower N rate（100–300 kg N/hm~2） are recommended to be a proper irrigation and N application strategy for plastic film-mulched hybrid maize seed production in arid Northwest China.