| Maize is one of the important food products in Hexi.The study of the effects of phosphorus application rate and drip irrigation rate on spring maize yield and nutrient utilization efficiency under the condition of water and fertilizer integration is of great significance for the efficient production of water and fertilizer.Take"Xianke 858"as the test material,set W1（80%ETc）,and W2（60%ETc）2 irrigation levels（ETc is crop evapotranspiration）and P0,P50,P100,P150 and P200 5 phosphate fertilizers Level（P2O5kg/ha）.During the growth period,the maize plant height,stem diameter,leaf area index,dry matter accumulation,yield,soil nutrient content and plant nutrient content were measured,and the results showed that:（1）Irrigation,phosphorus application and the interaction of the two have a significant impact on maize growth indicators and yield.Under the same irrigation amount,the growth indexes of maize first increased and then decreased with the increase of phosphorus application rate.The maximum dry matter accumulation of W1P100 in the mature period is30718.56 kg/hm2,while the maximum dry matter accumulation of W2P150 is 28685.65 kg/hm2.W1P100 increased by 7.09%compared with W2P150.The yield of corn in all treatments of W1was higher than that of W2.Among them,the yield of P100 was the highest in treatment W1,reaching 15278.78 kg/hm2,which was 3.58%-16.68%higher than that of other phosphorus treatments in W1.The yield of P150 in treatment W2 was the highest,reaching 14414.78 kg/hm2It is 1.92%-15.81%higher than other treatments in W2,and W1P100 is 6%higher than W2P150.（2）Under the same irrigation volume,water consumption first increased and then decreased with the increase of phosphate fertilizer application.The overall performance of water use efficiency and irrigation water use efficiency was that W2 treatment was higher than W1 treatment,and the irrigation water use efficiency was highest in W1 treatment and W2treatment respectively.W1P100 and W2P150,the values are 4.08 kg/m3 and 5.16 kg/m3,the lowest treatments are all P0 treatments,the values are 3.50 kg/m3 and 4.46 kg/m3,W2 treatment is 26.47%and 27.43%higher than W1 treatment,respectively.（3）Under the same water conditions,the cumulative nitrogen uptake of spring maize increased first and then decreased with the increase in phosphorus application rate.The cumulative nitrogen uptake of corn ears accounted for the highest proportion,80.78%-83.31%;in the mature stage,each in W1 Phosphorus application treatments were greater than those of W2,and increased by 11.02 kg/hm2-15.77 kg/hm2 compared with the filling stage.The cumulative phosphorus absorption of W1P100 was the highest at 62.72 kg/hm2,W2P0 was the lowest at 49.72 kg/hm2,and W1P100 was higher.W2P150 is 5.89%higher.With the increase of the amount of phosphorus applied,the cumulative amount of phosphorus first increased and then decreased.Different application rates of phosphate fertilizer have little effect on potassium.The maximum accumulation of P50 in the high water（W1）treatment is 200.61kg/hm2,and the maximum accumulation of P150 in the low water（W2）treatment is 201.39kg/hm2.Potassium is in the mature stage.Mainly concentrated in the stem.（4）Irrigation,phosphorus application and their interaction have greater impact on soil nitrate-nitrogen than available potassium.Soil nitrate-nitrogen mainly accumulates in the 0-40cm soil layer,and is consistent with the trend of soil phosphorus residues.High water（W1）treatment makes The soil nitrate nitrogen moves downward with water,and there is more nitrate nitrogen in the soil surface layer in the low water（W2）treatment.In the W1 treatments,the soil available potassium residue first decreased and then increased with the increase of the phosphorus application rate.In the W2 treatment,except for the W2P0 residue,the other treatments had no obvious rules.The potassium in the W1 treatment mainly accumulated in20-40cm.It accounts for 16.27%-25.06%of the total residue.In the W2 treatment,potassium mainly accumulates in 20-40cm,accounting for 11.13%-24.60%of the total residue.（5）The available phosphorus content in the soil increases with the increase in the amount of phosphorus applied.The W1 treatment is beneficial to the absorption of phosphate fertilizer by the plants and reduces the soil available phosphorus residue.The P50,P100,P150,P200 soil available phosphorus averages in the W1 and W2 treatments Compared with the control,the content increased by 22.59%,77.94%,84.71%,78.61%and 34.37%,82.78%,88.35%,93.92%.The W1 treatment was significantly lower than the W2 treatment.In W1treatment,when the yield was the highest,the surplus rate was 87%.At this time,the phosphorus application rate was 112.38 kg/hm2,the available phosphorus content of 0-40 cm soil was 10.88 mg/kg,and the partial productivity of maize was 129.08 kg/kg.Within the 95%confidence interval,the phosphorus application range is 106.76-117.99 kg/hm2. |
