Coupling Effect Of Water And Fertilizer On Spring Maize Under Drip Irrigation And Fertilization In Yanghuang Irrigation Area Of Ningxia

Aiming at the shortage of water resources and the low efficiency of crop water and fertilizer utilization in Yanghuang irrigation area,integrated drip irrigation and fertilization technology was adopted,"xianyu 335"was used as the experimental material,and four irrigation water quantities were set through the field spring corn plot test:I_0.75?0.75ETc.?,I_0.90(0.90ET_c.),I_1.05?1.05ET_c.?,I_1.20?120%ET_c.?,ET_c is the water requirement for corn.Four fertilizerrates?kg/hm²?:N-P₂O₅-K₂OwereF₁₅₀?150-70-70?,F₂₂₅?225-110-110?,F₃₀₀?300-150-150?,F₃₇₅?375-180-180?kg/hm²,and one high-water?120%ET_c?-no-fertilizer control?CK?,with a total of 17 treatments.During the growing period,the plant height,stem diameter,leaf area index,dry matter accumulation and yield of spring maize were observed,and the water and fertilizer utilization efficiency of spring maize was statistically analyzed to analyze the effects of different water and fertilizer supplies on the yield,growth morphological indexes,plant nitrogen uptake and utilization,and soil nitrate nitrogen distribution in root area.The test results show that:?1?Irrigation and fertilizer amount had significant effects on plant height,stem diameter,leaf area index,dry matter accumulation,yield and nitrogen uptake in mature stage of spring maize?P<0.05?.Irrigation water had a significant effect on the harvest index?P<0.05?.The dry matter accumulation was the highest under I_0.90F₃₇₅75 treatment,and dry matter accumulation of grains was the highest under I_0.90F₃₀₀00 treatment,which was 14.99%higher than that under I_0.90F₃₇₅75 treatment?P<0.05?.?2?Under the same irrigation condition,the yield first increased and then decreased with the increase of fertilizer application.The maximum yield was 16884 kg/hm² under I_0.90F₃₀₀00 treatment,which was 11.00%,7.32%and 13.85%higher than that under I_0.75F₃₀₀,I_1.05F₃₀₀00 and I_1.20F₃₀₀00 treatment,respectively?P<0.05?.The harvest index value of I_0.90F₁₅₀treatment was the largest,61.3%,which was not significantly different from that of I_0.90F₃₀₀treatment?P>0.05?,but decreased by 21.21%compared with that of the maximum yield treatment?P<0.05?.?3?The IWUE,WUE and PFP of spring maize were significantly affected by irrigation amount,fertilizer application amount and their interaction?P<0.01?.The IWUE and WUE values of I_0.75F₃₀₀00 and I_0.90F₃₀₀00 respectively reached the maximum values of 4.81kg/m³ and 2.69 kg/m³.The PFP value of spring maize decreased with the increase of fertilizer application.The PFP value of maximum yield treatment(I_0.90F₃₀₀)was 28.14kg/kg,showing no significant difference from that of I_1.05F₃₀₀?P>0.05?.Compared with that of I_0.75F₃₀₀00 and I_1.20F₃₀₀,the PFP value of spring maize increased by 11.00%and 13.88%respectively?P<0.05?.?4?The amount of irrigation and fertilizer had significant effects on the total nitrogen uptake of spring maize plants and grain nitrogen uptake?P<0.05?.Under the same irrigation condition,the total nitrogen accumulation of spring maize increased with the increase of nitrogen application.The variation range of nitrogen harvest index is 0.54⁰.66.Although the total nitrogen accumulation of plants treated with I_0.90F₃₇₅75 was significantly greater than that of other treatments?P<0.05?,there was no significant difference between the grain nitrogen accumulation and that treated with I_0.90F₃₀₀?P>0.05?,but the nitrogen harvest index was reduced.?5?The content of soil nitrate nitrogen in the root area of spring maize under drip irrigation was proportional to the amount of fertilizer applied and inversely proportional to the amount of irrigation water.In the mature stage,nitrate accumulation zones appeared repeatedly in the soil 40-60 cm below the drip head under the irrigation level of I_1.05.05 and I_1.20,and the higher the amount of fertilizer applied,the more obvious the phenomenon was.When both the amount of fertilizer and the amount of irrigation increased at the same time,the content of nitrate nitrogen in the soil layer of 60-100 cm tended to increase,making the difference between the soil layers tend to move down.However,in general,the difference in the content and distribution of nitrate nitrogen in the soil layer of 0-60 cm depth was greater than that in the soil layer of 60-100 cm depth.?6?Tosumup,itisrecommendedthatI_0.90F₃₀₀treatment?0.90ET_c,N-P₂O₅-K₂O?300-150-150kg/hm²??is a suitable drip irrigation and fertilizer management mode for spring maize in Yanghuang irrigation area in Ningxia.