Study On The Effect Of Balanced Fertilizer Application For Forage Maize In The Northwest Plateau Of Hebei Province

Northwest Plateau of Hebei Province is located in northern agriculture-animalhusbandry ecotone. So forage maize was planted to supply enough forage for animalproduction. With the forage maize Jinkun 8 under different nitrogen (N), phosphorus (P)and potassium (K) application rates, the experiment was conducted to analyze the effect offertilizer on the sandy chestnut soil experimental field of Zhangbei Experimental Station.The main results are as follows:1. On the sandy chestnut soil, plant high, stem width and LAI was improved bychemical fertilizer except fertilization without nitrogen, which promoted the yield of foragemaize by 45.2%～113.2% at the same time. Compared with CK, the yield under thetreatment without nitrogen was reduced by 4.4%. Compared equations of yield underdifferent fertilizer, it showed that fertilizer effect of nitrogen was maximal and that ofphosphorus was the minimal.2. The dynamic biomass yield described by Logistic curve equation. The highestrising rate (HRR), the time of HRR and linear rising period were changed by differenttreatments. HRR of maize under 135 kg N·ha^-1, or 90 kg P₂O₅·ha^-1, or 112.5 kg K₂O·ha^-1was promoted by 95.6%, 60.8% and 92.7%, and the time of HRR were earlier than CK for7.3d, 5.1 d and 5.4d。3. The nutrient and water absorption rates were influenced by fertilizer that drewdown changes of flow-rate and composition of bleeding sap, as well as water and nutrientuse efficiency. Compared with CK, the average of flow-rate of bleeding sap under 135 kgN·ha^-1, or 90 kg P₂O₅·ha^-1, or 112.5 kg K₂O·ha^-1 was promoted by 51.7%～117%. Differentfrom nutrients contents in plant, potassium content in bleeding sap was the most, nitrogenfollowing it.4. With higher nitrogen application rate, nitrogen apparent utilization ratio was raised,and it achieved 46.6%～59.7% exceeding the average of national rate. In reverse,phosphorus apparent utilization ratio was reduced after adding phosphorus application rate.Being different from former two factors, with potassium application rate promoted,potassium apparent utilization ratio was reduced in the beginning, but rose in the end.Promoted one nutrient input, the other two's nutrient apparent utilization ratio werepromoted. The three nutrient apparent utilization ratios could be improved with properNPK application rates. 5. Crude protein and crude fiber content are the two important indexs to evaluate thequality of forage. Crude content was increased with nitrogen and phosphorus, however,applied potassium showed the trend of lower crude protein; crude fiber was reduced withnitrogen application, however increased with phosphorus and potassium.Conten of crude protein(CP) and crude fat(EE) were increased with nitrogenapplication, however conten of crude fiber(CF), ash and nitrogen free extract(NFE) werereduced; Conten of CP, EE, CF and ash were increased with phosphorus application,however conten of NFE were reduced; conten of CF, ash and NFE were increased withpotassium application, however CP and EE were reduced.6. There were significantly positive correlations between the dynamic biomass yieldand water use efficiency or flow-rate of bleeding sap, R²=0.7761^**. Enough fertilizerapplication rate and proper ratio of N: P: K in field would be beneficial to build up goodmaize population, and supply enough plants mulching to reduce soil moisture evaporation,so that plants acquired benefit.