The effects of water-fertilizer integration on productivity of winter wheat and water-fertilizer utilizing efficiency under irrigation based on testing soil moisture

Abstract

In order to explore efficient technic of water-fertilizer irrigation of wheat and provide theoretical support for wheat farming, this research investigate the effects of micro sprinkling irrigation with 180 cm width on distribution of moisture and nutrient in soil, water and fertilizer consumption, and grain yield of winter wheat. Field test was carried out during growth season of wheat, Water-saving wheat variety “Heng4399” was used as test material. Four times of irrigation were implemented in Spring. Combining with soil moisture criterion during reproduction period, soil moisture was tested before each time of irrigation, and the sprinkling irrigation was initiated if drought appeared. The bands of sprinkler were set in between, and parallel to lines of wheat, with irrigation width of 1.8m, covering 6 lines of wheat (L1-L6) on each side of band. The experiment showed that wheat production reached to 7844.9-8194.8 kg/hm2, with no significant difference among the lines of wheat. The maximum accumulation of N and P2O5 appeared during maturity and reached to 260.25-295.95 kg/hm2 and 109.89-139.61 kg/hm2, respectively. The maximum accumulation of K2O was 251.35-297.29 kg/hm2 during anthesis stage. The difference of K2O accumulation among wheat lines was significant. The distribution of nutrients in each organ of wheat was irregular. These results suggested that the width of sprinkling irrigation had no significant effect on nutrient assimilation and productivity of wheat. Soil moisture was positively correlated to rapidly available phosphorus content before anthesis and alkali-hydrolysable nitrogen content in each layer of soil, and was negatively correlated to rapidly available potassium in late seed filling stage. Based on the results, we suggest that applying nitrogen fertilizer multiple times at different stages. Phosphorus fertilizer can be implemented at early reproduction stage based on nutrient demand of wheat. All potassium fertilizer is recommended to be applied as base manure.